Migrate spelling-0.0.21 changes from main

(cherry picked from commit bf0f516634)

.github/actions/spelling/README.md

@@ -6,6 +6,7 @@ File | Purpose | Format | Info
 [reject.txt](reject.txt) | Remove words from the dictionary (after allow) | grep pattern matching whole dictionary words | [reject](https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples%3A-reject)
 [excludes.txt](excludes.txt) | Files to ignore entirely | perl regular expression | [excludes](https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples%3A-excludes)
 [patterns/*.txt](patterns/) | Patterns to ignore from checked lines | perl regular expression (order matters, first match wins) | [patterns](https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples%3A-patterns)
+[candidate.patterns](candidate.patterns) | Patterns that might be worth adding to [patterns.txt](patterns.txt) | perl regular expression with optional comment block introductions (all matches will be suggested) | [candidates](https://github.com/check-spelling/check-spelling/wiki/Feature:-Suggest-patterns)
 [line_forbidden.patterns](line_forbidden.patterns) | Patterns to flag in checked lines | perl regular expression (order matters, first match wins) | [patterns](https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples%3A-patterns)
 [expect/*.txt](expect.txt) | Expected words that aren't in the dictionary | one word per line (sorted, alphabetically) | [expect](https://github.com/check-spelling/check-spelling/wiki/Configuration#expect)
 [advice.md](advice.md) | Supplement for GitHub comment when unrecognized words are found | GitHub Markdown | [advice](https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples%3A-advice)

.github/actions/spelling/advice.md

@@ -21,7 +21,7 @@ See the `README.md` in each directory for more information.
 :microscope: You can test your commits **without** *appending* to a PR by creating a new branch with that extra change and pushing it to your fork. The [check-spelling](https://github.com/marketplace/actions/check-spelling) action will run in response to your **push** -- it doesn't require an open pull request. By using such a branch, you can limit the number of typos your peers see you make. :wink:
 
 
-<details><summary>:clamp: If the flagged items are false positives</summary>
+<details><summary>If the flagged items are :exploding_head: false positives</summary>
 
 If items relate to a ...
 * binary file (or some other file you wouldn't want to check at all).

.github/actions/spelling/allow/allow.txt

@@ -1,7 +1,7 @@
 admins
 allcolors
-apc
 Apc
+apc
 breadcrumb
 breadcrumbs
 bsd
@@ -14,8 +14,8 @@ CMMI
 copyable
 cybersecurity
 dalet
-dcs
 Dcs
+dcs
 dialytika
 dje
 downside
@@ -34,10 +34,12 @@ gantt
 gcc
 geeksforgeeks
 ghe
+github
 gje
 godbolt
 hostname
 hostnames
+https
 hyperlink
 hyperlinking
 hyperlinks
@@ -54,9 +56,11 @@ Llast
 llvm
 Lmid
 locl
+lol
 lorem
 Lorigin
 maxed
+minimalistic
 mkmk
 mnt
 mru
@@ -80,6 +84,7 @@ runtimes
 shcha
 slnt
 Sos
+ssh
 timeline
 timelines
 timestamped
@@ -88,6 +93,7 @@ tokenizes
 tonos
 toolset
 tshe
+ubuntu
 uiatextrange
 UIs
 und
@@ -96,5 +102,7 @@ versioned
 vsdevcmd
 We'd
 wildcards
+XBox
+YBox
 yeru
 zhe

.github/actions/spelling/allow/apis.txt

@@ -32,10 +32,10 @@ DERR
 dlldata
 DNE
 DONTADDTORECENT
-DWMWA
-DWORDLONG
 DWMSBT
 DWMWA
+DWMWA
+DWORDLONG
 endfor
 ENDSESSION
 enumset
@@ -110,8 +110,8 @@ memchr
 memicmp
 MENUCOMMAND
 MENUDATA
-MENUITEMINFOW
 MENUINFO
+MENUITEMINFOW
 mmeapi
 MOUSELEAVE
 mov
@@ -158,8 +158,8 @@ rcx
 REGCLS
 RETURNCMD
 rfind
-roundf
 ROOTOWNER
+roundf
 RSHIFT
 SACL
 schandle
@@ -211,6 +211,7 @@ UPDATEINIFILE
 userenv
 USEROBJECTFLAGS
 Viewbox
+virtualalloc
 wcsstr
 wcstoui
 winmain

.github/actions/spelling/candidate.patterns

@@ -0,0 +1,523 @@
+# marker to ignore all code on line
+^.*/\* #no-spell-check-line \*/.*$
+# marker for ignoring a comment to the end of the line
+// #no-spell-check.*$
+
+# patch hunk comments
+^\@\@ -\d+(?:,\d+|) \+\d+(?:,\d+|) \@\@ .*
+# git index header
+index [0-9a-z]{7,40}\.\.[0-9a-z]{7,40}
+
+# cid urls
+(['"])cid:.*?\g{-1}
+
+# data url in parens
+\(data:[^)]*?(?:[A-Z]{3,}|[A-Z][a-z]{2,}|[a-z]{3,})[^)]*\)
+# data url in quotes
+([`'"])data:.*?(?:[A-Z]{3,}|[A-Z][a-z]{2,}|[a-z]{3,}).*\g{-1}
+# data url
+data:[-a-zA-Z=;:/0-9+]*,\S*
+
+# mailto urls
+mailto:[-a-zA-Z=;:/?%&0-9+@.]{3,}
+
+# magnet urls
+magnet:[?=:\w]+
+
+# magnet urls
+"magnet:[^"]+"
+
+# obs:
+"obs:[^"]*"
+
+# The `\b` here means a break, it's the fancy way to handle urls, but it makes things harder to read
+# In this examples content, I'm using a number of different ways to match things to show various approaches
+# asciinema
+\basciinema\.org/a/[0-9a-zA-Z]+
+
+# apple
+\bdeveloper\.apple\.com/[-\w?=/]+
+# Apple music
+\bembed\.music\.apple\.com/fr/playlist/usr-share/[-\w.]+
+
+# appveyor api
+\bci\.appveyor\.com/api/projects/status/[0-9a-z]+
+# appveyor project
+\bci\.appveyor\.com/project/(?:[^/\s"]*/){2}builds?/\d+/job/[0-9a-z]+
+
+# Amazon
+
+# Amazon
+\bamazon\.com/[-\w]+/(?:dp/[0-9A-Z]+|)
+# AWS S3
+\b\w*\.s3[^.]*\.amazonaws\.com/[-\w/&#%_?:=]*
+# AWS execute-api
+\b[0-9a-z]{10}\.execute-api\.[-0-9a-z]+\.amazonaws\.com\b
+# AWS ELB
+\b\w+\.[-0-9a-z]+\.elb\.amazonaws\.com\b
+# AWS SNS
+\bsns\.[-0-9a-z]+.amazonaws\.com/[-\w/&#%_?:=]*
+# AWS VPC
+vpc-\w+
+
+# While you could try to match `http://` and `https://` by using `s?` in `https?://`, sometimes there
+# YouTube url
+\b(?:(?:www\.|)youtube\.com|youtu.be)/(?:channel/|embed/|user/|playlist\?list=|watch\?v=|v/|)[-a-zA-Z0-9?&=_%]*
+# YouTube music
+\bmusic\.youtube\.com/youtubei/v1/browse(?:[?&]\w+=[-a-zA-Z0-9?&=_]*)
+# YouTube tag
+<\s*youtube\s+id=['"][-a-zA-Z0-9?_]*['"]
+# YouTube image
+\bimg\.youtube\.com/vi/[-a-zA-Z0-9?&=_]*
+# Google Accounts
+\baccounts.google.com/[-_/?=.:;+%&0-9a-zA-Z]*
+# Google Analytics
+\bgoogle-analytics\.com/collect.[-0-9a-zA-Z?%=&_.~]*
+# Google APIs
+\bgoogleapis\.(?:com|dev)/[a-z]+/(?:v\d+/|)[a-z]+/[-@:./?=\w+|&]+
+# Google Storage
+\b[-a-zA-Z0-9.]*\bstorage\d*\.googleapis\.com(?:/\S*|)
+# Google Calendar
+\bcalendar\.google\.com/calendar(?:/u/\d+|)/embed\?src=[@./?=\w&%]+
+\w+\@group\.calendar\.google\.com\b
+# Google DataStudio
+\bdatastudio\.google\.com/(?:(?:c/|)u/\d+/|)(?:embed/|)(?:open|reporting|datasources|s)/[-0-9a-zA-Z]+(?:/page/[-0-9a-zA-Z]+|)
+# The leading `/` here is as opposed to the `\b` above
+# ... a short way to match `https://` or `http://` since most urls have one of those prefixes
+# Google Docs
+/docs\.google\.com/[a-z]+/(?:ccc\?key=\w+|(?:u/\d+|d/(?:e/|)[0-9a-zA-Z_-]+/)?(?:edit\?[-\w=#.]*|/\?[\w=&]*|))
+# Google Drive
+\bdrive\.google\.com/(?:file/d/|open)[-0-9a-zA-Z_?=]*
+# Google Groups
+\bgroups\.google\.com/(?:(?:forum/#!|d/)(?:msg|topics?|searchin)|a)/[^/\s"]+/[-a-zA-Z0-9$]+(?:/[-a-zA-Z0-9]+)*
+# Google Maps
+\bmaps\.google\.com/maps\?[\w&;=]*
+# Google themes
+themes\.googleusercontent\.com/static/fonts/[^/\s"]+/v\d+/[^.]+.
+# Google CDN
+\bclients2\.google(?:usercontent|)\.com[-0-9a-zA-Z/.]*
+# Goo.gl
+/goo\.gl/[a-zA-Z0-9]+
+# Google Chrome Store
+\bchrome\.google\.com/webstore/detail/[-\w]*(?:/\w*|)
+# Google Books
+\bgoogle\.(?:\w{2,4})/books(?:/\w+)*\?[-\w\d=&#.]*
+# Google Fonts
+\bfonts\.(?:googleapis|gstatic)\.com/[-/?=:;+&0-9a-zA-Z]*
+# Google Forms
+\bforms\.gle/\w+
+# Google Scholar
+\bscholar\.google\.com/citations\?user=[A-Za-z0-9_]+
+# Google Colab Research Drive
+\bcolab\.research\.google\.com/drive/[-0-9a-zA-Z_?=]*
+
+# GitHub SHAs (api)
+\bapi.github\.com/repos(?:/[^/\s"]+){3}/[0-9a-f]+\b
+# GitHub SHAs (markdown)
+(?:\[`?[0-9a-f]+`?\]\(https:/|)/(?:www\.|)github\.com(?:/[^/\s"]+){2,}(?:/[^/\s")]+)(?:[0-9a-f]+(?:[-0-9a-zA-Z/#.]*|)\b|)
+# GitHub SHAs
+\bgithub\.com(?:/[^/\s"]+){2}[@#][0-9a-f]+\b
+# GitHub wiki
+\bgithub\.com/(?:[^/]+/){2}wiki/(?:(?:[^/]+/|)_history|[^/]+(?:/_compare|)/[0-9a-f.]{40,})\b
+# githubusercontent
+/[-a-z0-9]+\.githubusercontent\.com/[-a-zA-Z0-9?&=_\/.]*
+# githubassets
+\bgithubassets.com/[0-9a-f]+(?:[-/\w.]+)
+# gist github
+\bgist\.github\.com/[^/\s"]+/[0-9a-f]+
+# git.io
+\bgit\.io/[0-9a-zA-Z]+
+# GitHub JSON
+"node_id": "[-a-zA-Z=;:/0-9+]*"
+# Contributor
+\[[^\]]+\]\(https://github\.com/[^/\s"]+\)
+# GHSA
+GHSA(?:-[0-9a-z]{4}){3}
+
+# GitLab commit
+\bgitlab\.[^/\s"]*/\S+/\S+/commit/[0-9a-f]{7,16}#[0-9a-f]{40}\b
+# GitLab merge requests
+\bgitlab\.[^/\s"]*/\S+/\S+/-/merge_requests/\d+/diffs#[0-9a-f]{40}\b
+# GitLab uploads
+\bgitlab\.[^/\s"]*/uploads/[-a-zA-Z=;:/0-9+]*
+# GitLab commits
+\bgitlab\.[^/\s"]*/(?:[^/\s"]+/){2}commits?/[0-9a-f]+\b
+
+# binanace
+accounts.binance.com/[a-z/]*oauth/authorize\?[-0-9a-zA-Z&%]*
+
+# bitbucket diff
+\bapi\.bitbucket\.org/\d+\.\d+/repositories/(?:[^/\s"]+/){2}diff(?:stat|)(?:/[^/\s"]+){2}:[0-9a-f]+
+# bitbucket repositories commits
+\bapi\.bitbucket\.org/\d+\.\d+/repositories/(?:[^/\s"]+/){2}commits?/[0-9a-f]+
+# bitbucket commits
+\bbitbucket\.org/(?:[^/\s"]+/){2}commits?/[0-9a-f]+
+
+# bit.ly
+\bbit\.ly/\w+
+
+# bitrise
+\bapp\.bitrise\.io/app/[0-9a-f]*/[\w.?=&]*
+
+# bootstrapcdn.com
+\bbootstrapcdn\.com/[-./\w]+
+
+# cdn.cloudflare.com
+\bcdnjs\.cloudflare\.com/[./\w]+
+
+# circleci
+\bcircleci\.com/gh(?:/[^/\s"]+){1,5}.[a-z]+\?[-0-9a-zA-Z=&]+
+
+# gitter
+\bgitter\.im(?:/[^/\s"]+){2}\?at=[0-9a-f]+
+
+# gravatar
+\bgravatar\.com/avatar/[0-9a-f]+
+
+# ibm
+[a-z.]*ibm\.com/[-_#=:%!?~.\\/\d\w]*
+
+# imgur
+\bimgur\.com/[^.]+
+
+# Internet Archive
+\barchive\.org/web/\d+/(?:[-\w.?,'/\\+&%$#_:]*)
+
+# discord
+/discord(?:app\.com|\.gg)/(?:invite/)?[a-zA-Z0-9]{7,}
+
+# Disqus
+\bdisqus\.com/[-\w/%.()!?&=_]*
+
+# medium link
+\blink\.medium\.com/[a-zA-Z0-9]+
+# medium
+\bmedium\.com/\@?[^/\s"]+/[-\w]+
+
+# microsoft
+\b(?:https?://|)(?:(?:download\.visualstudio|docs|msdn2?|research)\.microsoft|blogs\.msdn)\.com/[-_a-zA-Z0-9()=./%]*
+# powerbi
+\bapp\.powerbi\.com/reportEmbed/[^"' ]*
+# vs devops
+\bvisualstudio.com(?::443|)/[-\w/?=%&.]*
+# microsoft store
+\bmicrosoft\.com/store/apps/\w+
+
+# mvnrepository.com
+\bmvnrepository\.com/[-0-9a-z./]+
+
+# now.sh
+/[0-9a-z-.]+\.now\.sh\b
+
+# oracle
+\bdocs\.oracle\.com/[-0-9a-zA-Z./_?#&=]*
+
+# chromatic.com
+/\S+.chromatic.com\S*[")]
+
+# codacy
+\bapi\.codacy\.com/project/badge/Grade/[0-9a-f]+
+
+# compai
+\bcompai\.pub/v1/png/[0-9a-f]+
+
+# mailgun api
+\.api\.mailgun\.net/v3/domains/[0-9a-z]+\.mailgun.org/messages/[0-9a-zA-Z=@]*
+# mailgun
+\b[0-9a-z]+.mailgun.org
+
+# /message-id/
+/message-id/[-\w@./%]+
+
+# Reddit
+\breddit\.com/r/[/\w_]*
+
+# requestb.in
+\brequestb\.in/[0-9a-z]+
+
+# sched
+\b[a-z0-9]+\.sched\.com\b
+
+# Slack url
+slack://[a-zA-Z0-9?&=]+
+# Slack
+\bslack\.com/[-0-9a-zA-Z/_~?&=.]*
+# Slack edge
+\bslack-edge\.com/[-a-zA-Z0-9?&=%./]+
+# Slack images
+\bslack-imgs\.com/[-a-zA-Z0-9?&=%.]+
+
+# shields.io
+\bshields\.io/[-\w/%?=&.:+;,]*
+
+# stackexchange -- https://stackexchange.com/feeds/sites
+\b(?:askubuntu|serverfault|stack(?:exchange|overflow)|superuser).com/(?:questions/\w+/[-\w]+|a/)
+
+# Sentry
+[0-9a-f]{32}\@o\d+\.ingest\.sentry\.io\b
+
+# Twitter markdown
+\[\@[^[/\]:]*?\]\(https://twitter.com/[^/\s"')]*(?:/status/\d+(?:\?[-_0-9a-zA-Z&=]*|)|)\)
+# Twitter hashtag
+\btwitter\.com/hashtag/[\w?_=&]*
+# Twitter status
+\btwitter\.com/[^/\s"')]*(?:/status/\d+(?:\?[-_0-9a-zA-Z&=]*|)|)
+# Twitter profile images
+\btwimg\.com/profile_images/[_\w./]*
+# Twitter media
+\btwimg\.com/media/[-_\w./?=]*
+# Twitter link shortened
+\bt\.co/\w+
+
+# facebook
+\bfburl\.com/[0-9a-z_]+
+# facebook CDN
+\bfbcdn\.net/[\w/.,]*
+# facebook watch
+\bfb\.watch/[0-9A-Za-z]+
+
+# dropbox
+\bdropbox\.com/sh?/[^/\s"]+/[-0-9A-Za-z_.%?=&;]+
+
+# ipfs protocol
+ipfs://[0-9a-z]*
+# ipfs url
+/ipfs/[0-9a-z]*
+
+# w3
+\bw3\.org/[-0-9a-zA-Z/#.]+
+
+# loom
+\bloom\.com/embed/[0-9a-f]+
+
+# regex101
+\bregex101\.com/r/[^/\s"]+/\d+
+
+# figma
+\bfigma\.com/file(?:/[0-9a-zA-Z]+/)+
+
+# freecodecamp.org
+\bfreecodecamp\.org/[-\w/.]+
+
+# image.tmdb.org
+\bimage\.tmdb\.org/[/\w.]+
+
+# mermaid
+\bmermaid\.ink/img/[-\w]+|\bmermaid-js\.github\.io/mermaid-live-editor/#/edit/[-\w]+
+
+# Wikipedia
+\ben\.wikipedia\.org/wiki/[-\w%.#]+
+
+# gitweb
+[^"\s]+/gitweb/\S+;h=[0-9a-f]+
+
+# HyperKitty lists
+/archives/list/[^@/]+\@[^/\s"]*/message/[^/\s"]*/
+
+# lists
+/thread\.html/[^"\s]+
+
+# list-management
+\blist-manage\.com/subscribe(?:[?&](?:u|id)=[0-9a-f]+)+
+
+# kubectl.kubernetes.io/last-applied-configuration
+"kubectl.kubernetes.io/last-applied-configuration": ".*"
+
+# pgp
+\bgnupg\.net/pks/lookup[?&=0-9a-zA-Z]*
+
+# Spotify
+\bopen\.spotify\.com/embed/playlist/\w+
+
+# Mastodon
+\bmastodon\.[-a-z.]*/(?:media/|\@)[?&=0-9a-zA-Z_]*
+
+# scastie
+\bscastie\.scala-lang\.org/[^/]+/\w+
+
+# images.unsplash.com
+\bimages\.unsplash\.com/(?:(?:flagged|reserve)/|)[-\w./%?=%&.;]+
+
+# pastebin
+\bpastebin\.com/[\w/]+
+
+# heroku
+\b\w+\.heroku\.com/source/archive/\w+
+
+# quip
+\b\w+\.quip\.com/\w+(?:(?:#|/issues/)\w+)?
+
+# badgen.net
+\bbadgen\.net/badge/[^")\]'\s]+
+
+# statuspage.io
+\w+\.statuspage\.io\b
+
+# media.giphy.com
+\bmedia\.giphy\.com/media/[^/]+/[\w.?&=]+
+
+# tinyurl
+\btinyurl\.com/\w+
+
+# getopts
+\bgetopts\s+(?:"[^"]+"|'[^']+')
+
+# ANSI color codes
+(?:\\(?:u00|x)1b|\x1b)\[\d+(?:;\d+|)m
+
+# URL escaped characters
+\%[0-9A-F][A-F]
+# IPv6
+\b(?:[0-9a-fA-F]{0,4}:){3,7}[0-9a-fA-F]{0,4}\b
+# c99 hex digits (not the full format, just one I've seen)
+0x[0-9a-fA-F](?:\.[0-9a-fA-F]*|)[pP]
+# Punycode
+\bxn--[-0-9a-z]+
+# sha
+sha\d+:[0-9]*[a-f]{3,}[0-9a-f]*
+# sha-... -- uses a fancy capture
+(['"]|&quot;)[0-9a-f]{40,}\g{-1}
+# hex runs
+\b[0-9a-fA-F]{16,}\b
+# hex in url queries
+=[0-9a-fA-F]*?(?:[A-F]{3,}|[a-f]{3,})[0-9a-fA-F]*?&
+# ssh
+(?:ssh-\S+|-nistp256) [-a-zA-Z=;:/0-9+]{12,}
+
+# PGP
+\b(?:[0-9A-F]{4} ){9}[0-9A-F]{4}\b
+# GPG keys
+\b(?:[0-9A-F]{4} ){5}(?: [0-9A-F]{4}){5}\b
+# Well known gpg keys
+.well-known/openpgpkey/[\w./]+
+
+# uuid:
+\b[0-9a-fA-F]{8}-(?:[0-9a-fA-F]{4}-){3}[0-9a-fA-F]{12}\b
+# hex digits including css/html color classes:
+(?:[\\0][xX]|\\u|[uU]\+|#x?|\%23)[0-9_a-fA-FgGrR]*?[a-fA-FgGrR]{2,}[0-9_a-fA-FgGrR]*(?:[uUlL]{0,3}|u\d+)\b
+# integrity
+integrity="sha\d+-[-a-zA-Z=;:/0-9+]{40,}"
+
+# https://www.gnu.org/software/groff/manual/groff.html
+# man troff content
+\\f[BCIPR]
+# '
+\\\(aq
+
+# .desktop mime types
+^MimeTypes?=.*$
+# .desktop localized entries
+^[A-Z][a-z]+\[[a-z]+\]=.*$
+# Localized .desktop content
+Name\[[^\]]+\]=.*
+
+# IServiceProvider
+\bI(?=(?:[A-Z][a-z]{2,})+\b)
+
+# crypt
+"\$2[ayb]\$.{56}"
+
+# scrypt / argon
+\$(?:scrypt|argon\d+[di]*)\$\S+
+
+# Input to GitHub JSON
+content: "[-a-zA-Z=;:/0-9+]*="
+
+# Python stringprefix / binaryprefix
+# Note that there's a high false positive rate, remove the `?=` and search for the regex to see if the matches seem like reasonable strings
+(?<!')\b(?:B|BR|Br|F|FR|Fr|R|RB|RF|Rb|Rf|U|UR|Ur|b|bR|br|f|fR|fr|r|rB|rF|rb|rf|u|uR|ur)'(?:[A-Z]{3,}|[A-Z][a-z]{2,}|[a-z]{3,})
+
+# Regular expressions for (P|p)assword
+\([A-Z]\|[a-z]\)[a-z]+
+
+# JavaScript regular expressions
+# javascript test regex
+/.*/[gim]*\.test\(
+# javascript match regex
+\.match\(/[^/\s"]*/[gim]*\s*
+# javascript match regex
+\.match\(/\\[b].*?/[gim]*\s*\)(?:;|$)
+# javascript regex
+^\s*/\\[b].*/[gim]*\s*(?:\)(?:;|$)|,$)
+# javascript replace regex
+\.replace\(/[^/\s"]*/[gim]*\s*,
+
+# Go regular expressions
+regexp?\.MustCompile\(`[^`]*`\)
+
+# sed regular expressions
+sed 's/(?:[^/]*?[a-zA-Z]{3,}[^/]*?/){2}
+
+# go install
+go install(?:\s+[a-z]+\.[-@\w/.]+)+
+
+# kubernetes pod status lists
+# https://kubernetes.io/docs/concepts/workloads/pods/pod-lifecycle/#pod-phase
+\w+(?:-\w+)+\s+\d+/\d+\s+(?:Running|Pending|Succeeded|Failed|Unknown)\s+
+
+# kubectl - pods in CrashLoopBackOff
+\w+-[0-9a-f]+-\w+\s+\d+/\d+\s+CrashLoopBackOff\s+
+
+# kubernetes object suffix
+-[0-9a-f]{10}-\w{5}\s
+
+# posthog secrets
+posthog\.init\((['"])phc_[^"',]+\g{-1},
+
+# xcode
+
+# xcodeproject scenes
+(?:Controller|ID|id)="\w{3}-\w{2}-\w{3}"
+
+# xcode api botches
+customObjectInstantitationMethod
+
+# font awesome classes
+\.fa-[-a-z0-9]+
+
+# Update Lorem based on your content (requires `ge` and `w` from https://github.com/jsoref/spelling; and `review` from https://github.com/check-spelling/check-spelling/wiki/Looking-for-items-locally )
+# grep '^[^#].*lorem' .github/actions/spelling/patterns.txt|perl -pne 's/.*i..\?://;s/\).*//' |tr '|' "\n"|sort -f |xargs -n1 ge|perl -pne 's/^[^:]*://'|sort -u|w|sed -e 's/ .*//'|w|review -
+# Warning, while `(?i)` is very neat and fancy, if you have some binary files that aren't proper unicode, you might run into:
+## Operation "substitution (s///)" returns its argument for non-Unicode code point 0x1C19AE (the code point will vary).
+## You could manually change `(?i)X...` to use `[Xx]...`
+## or you could add the files to your `excludes` file (a version after 0.0.19 should identify the file path)
+# Lorem
+(?:\w|\s|[,.])*\b(?i)(?:amet|consectetur|cursus|dolor|eros|ipsum|lacus|libero|ligula|lorem|magna|neque|nulla|suscipit|tempus)\b(?:\w|\s|[,.])*
+
+# Non-English
+[a-zA-Z]*[ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýÿĀāŁłŃńŅņŒœŚśŠšŜŝŸŽžź][a-zA-Z]{3}[a-zA-ZÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýÿĀāŁłŃńŅņŒœŚśŠšŜŝŸŽžź]*
+
+# French
+# This corpus only had capital letters, but you probably want lowercase ones as well.
+\b[LN]'+[a-z]{2,}\b
+
+# latex
+\\(?:n(?:ew|ormal|osub)|r(?:enew)|t(?:able(?:of|)|he|itle))(?=[a-z]+)
+
+# the negative lookahead here is to allow catching 'templatesz' as a misspelling
+# but to otherwise recognize a Windows path with \templates\foo.template or similar:
+\\(?:necessary|r(?:eport|esolve[dr]?|esult)|t(?:arget|emplates?))(?![a-z])
+# ignore long runs of a single character:
+\b([A-Za-z])\g{-1}{3,}\b
+# Note that the next example is no longer necessary if you are using
+# to match a string starting with a `#`, use a character-class:
+[#]backwards
+# version suffix <word>v#
+(?:(?<=[A-Z]{2})V|(?<=[a-z]{2}|[A-Z]{2})v)\d+(?:\b|(?=[a-zA-Z_]))
+# Compiler flags (Scala)
+(?:^|[\t ,>"'`=(])-J-[DPWXY](?=[A-Z]{2,}|[A-Z][a-z]|[a-z]{2,})
+# Compiler flags
+#(?:^|[\t ,"'`=(])-[DPWXYLlf](?=[A-Z]{2,}|[A-Z][a-z]|[a-z]{2,})
+
+# Compiler flags (linker)
+,-B
+# curl arguments
+\b(?:\\n|)curl(?:\s+-[a-zA-Z]{1,2}\b)*(?:\s+-[a-zA-Z]{3,})(?:\s+-[a-zA-Z]+)*
+# set arguments
+\bset(?:\s+-[abefimouxE]{1,2})*\s+-[abefimouxE]{3,}(?:\s+-[abefimouxE]+)*
+# tar arguments
+\b(?:\\n|)g?tar(?:\.exe|)(?:(?:\s+--[-a-zA-Z]+|\s+-[a-zA-Z]+|\s[ABGJMOPRSUWZacdfh-pr-xz]+\b)(?:=[^ ]*|))+
+# tput arguments -- https://man7.org/linux/man-pages/man5/terminfo.5.html -- technically they can be more than 5 chars long...
+\btput\s+(?:(?:-[SV]|-T\s*\w+)\s+)*\w{3,5}\b
+# macOS temp folders
+/var/folders/\w\w/[+\w]+/(?:T|-Caches-)/

.github/actions/spelling/excludes.txt

@@ -2,14 +2,14 @@
 (?:(?i)\.png$)
 (?:^|/)(?i)COPYRIGHT
 (?:^|/)(?i)LICEN[CS]E
+(?:^|/)3rdparty/
 (?:^|/)dirs$
 (?:^|/)go\.mod$
 (?:^|/)go\.sum$
 (?:^|/)package(?:-lock|)\.json$
 (?:^|/)sources(?:|\.dep)$
 (?:^|/)vendor/
-ignore$
-SUMS$
+\.a$
 \.ai$
 \.avi$
 \.bmp$
@@ -20,6 +20,8 @@ SUMS$
 \.crt$
 \.csr$
 \.dll$
+\.docx?$
+\.drawio$
 \.DS_Store$
 \.eot$
 \.eps$
@@ -31,6 +33,7 @@ SUMS$
 \.icns$
 \.ico$
 \.jar$
+\.jks$
 \.jpeg$
 \.jpg$
 \.key$
@@ -41,6 +44,7 @@ SUMS$
 \.mod$
 \.mp3$
 \.mp4$
+\.o$
 \.ocf$
 \.otf$
 \.pbxproj$
@@ -48,22 +52,41 @@ SUMS$
 \.pem$
 \.png$
 \.psd$
+\.pyc$
 \.runsettings$
+\.s$
 \.sig$
 \.so$
 \.svg$
 \.svgz$
+\.svgz?$
 \.tar$
 \.tgz$
+\.tiff?$
 \.ttf$
 \.vsdx$
 \.wav$
+\.webm$
+\.webp$
 \.woff
+\.woff2?$
 \.xcf$
 \.xls
+\.xlsx?$
 \.xpm$
 \.yml$
 \.zip$
+^\.github/actions/spelling/
+^\.github/fabricbot.json$
+^\.gitignore$
+^\Q.git-blame-ignore-revs\E$
+^\Q.github/workflows/spelling.yml\E$
+^\Qdoc/reference/windows-terminal-logo.ans\E$
+^\Qsamples/ConPTY/EchoCon/EchoCon/EchoCon.vcxproj.filters\E$
+^\Qsrc/host/exe/Host.EXE.vcxproj.filters\E$
+^\Qsrc/host/ft_host/chafa.txt\E$
+^\Qsrc/tools/closetest/CloseTest.vcxproj.filters\E$
+^\XamlStyler.json$
 ^build/config/
 ^consolegit2gitfilters\.json$
 ^dep/
@@ -90,12 +113,5 @@ SUMS$
 ^src/tools/U8U16Test/(?:fr|ru|zh)\.txt$
 ^src/types/ut_types/UtilsTests.cpp$
 ^tools/ReleaseEngineering/ServicingPipeline.ps1$
-^\.github/actions/spelling/
-^\.github/fabricbot.json$
-^\.gitignore$
-^\Q.github/workflows/spelling.yml\E$
-^\Qsamples/ConPTY/EchoCon/EchoCon/EchoCon.vcxproj.filters\E$
-^\Qsrc/host/exe/Host.EXE.vcxproj.filters\E$
-^\Qsrc/host/ft_host/chafa.txt\E$
-^\Qsrc/tools/closetest/CloseTest.vcxproj.filters\E$
-^\XamlStyler.json$
+ignore$
+SUMS$

.github/actions/spelling/expect/alphabet.txt

@@ -5,26 +5,19 @@ AAAAAABBBBBBCCC
 AAAAABBBBBBCCC
 abcd
 abcd
-abcde
-abcdef
-ABCDEFG
-ABCDEFGH
 ABCDEFGHIJ
 abcdefghijk
 ABCDEFGHIJKLMNO
 abcdefghijklmnop
 ABCDEFGHIJKLMNOPQRST
-abcdefghijklmnopqrstuvwxyz
 ABCG
 ABE
 abf
 BBBBB
 BBBBBBBB
-BBBBBBBBBBBBBBDDDD
 BBBBBCCC
 BBBBCCCCC
 BBGGRR
-CCE
 EFG
 EFGh
 QQQQQQQQQQABCDEFGHIJ

.github/actions/spelling/expect/web.txt

@@ -1,5 +1,3 @@
-http
-www
 WCAG
 winui
 appshellintegration

.github/actions/spelling/line_forbidden.patterns

@@ -1,3 +1,11 @@
+# reject `m_data` as there's a certain OS which has evil defines that break things if it's used elsewhere
+# \bm_data\b
+
+# If you have a framework that uses `it()` for testing and `fit()` for debugging a specific test,
+# you might not want to check in code where you were debugging w/ `fit()`, in which case, you might want
+# to use this:
+#\bfit\(
+
 # s.b. GitHub
 \bGithub\b
 
@@ -16,6 +24,12 @@
 # s.b. greater than
 \bgreater then\b
 
+# s.b. into
+#\sin to\s
+
+# s.b. opt-in
+\sopt in\s
+
 # s.b. less than
 \bless then\b
 
@@ -27,10 +41,22 @@
 \b[Nn]o[nt][- ]existent\b
 
 # s.b. preexisting
-[Pp]re-existing
+[Pp]re[- ]existing
+
+# s.b. preempt
+[Pp]re[- ]empt\b
 
 # s.b. preemptively
-[Pp]re-emptively
+[Pp]re[- ]emptively
+
+# s.b. reentrancy
+[Rr]e[- ]entrancy
+
+# s.b. reentrant
+[Rr]e[- ]entrant
+
+# s.b. workaround(s)
+#\bwork[- ]arounds?\b
 
 # Reject duplicate words
 \s([A-Z]{3,}|[A-Z][a-z]{2,}|[a-z]{3,})\s\g{-1}\s

.github/actions/spelling/patterns/patterns.txt

@@ -27,13 +27,68 @@ ROY\sG\.\sBIV
 # Python stringprefix / binaryprefix
 \b(?:B|BR|Br|F|FR|Fr|R|RB|RF|Rb|Rf|U|UR|Ur|b|bR|br|f|fR|fr|r|rB|rF|rb|rf|u|uR|ur)'
 
+# Automatically suggested patterns
+# hit-count: 3831 file-count: 582
+# IServiceProvider
+\bI(?=(?:[A-Z][a-z]{2,})+\b)
+
+# hit-count: 71 file-count: 35
+# Compiler flags
+(?:^|[\t ,"'`=(])-[D](?=[A-Z]{2,}|[A-Z][a-z])
+(?:^|[\t ,"'`=(])-[X](?=[A-Z]{2,}|[A-Z][a-z]|[a-z]{2,})
+
+# hit-count: 41 file-count: 28
+# version suffix <word>v#
+(?:(?<=[A-Z]{2})V|(?<=[a-z]{2}|[A-Z]{2})v)\d+(?:\b|(?=[a-zA-Z_]))
+
+# hit-count: 20 file-count: 9
+# hex runs
+\b[0-9a-fA-F]{16,}\b
+
+# hit-count: 10 file-count: 7
+# uuid:
+\b[0-9a-fA-F]{8}-(?:[0-9a-fA-F]{4}-){3}[0-9a-fA-F]{12}\b
+
+# hit-count: 4 file-count: 4
+# mailto urls
+mailto:[-a-zA-Z=;:/?%&0-9+@.]{3,}
+
+# hit-count: 4 file-count: 1
+# ANSI color codes
+(?:\\(?:u00|x)1b|\x1b)\[\d+(?:;\d+|)m
+
+# hit-count: 2 file-count: 1
+# latex
+\\(?:n(?:ew|ormal|osub)|r(?:enew)|t(?:able(?:of|)|he|itle))(?=[a-z]+)
+
+# hit-count: 1 file-count: 1
+# hex digits including css/html color classes:
+(?:[\\0][xX]|\\u|[uU]\+|#x?|\%23)[0-9_a-fA-FgGrR]*?[a-fA-FgGrR]{2,}[0-9_a-fA-FgGrR]*(?:[uUlL]{0,3}|u\d+)\b
+
+# hit-count: 1 file-count: 1
+# Non-English
+[a-zA-Z]*[ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýÿĀāŁłŃńŅņŒœŚśŠšŜŝŸŽžź][a-zA-Z]{3}[a-zA-ZÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýÿĀāŁłŃńŅņŒœŚśŠšŜŝŸŽžź]*
+
+# hit-count: 1 file-count: 1
+# French
+# This corpus only had capital letters, but you probably want lowercase ones as well.
+\b[LN]'+[a-z]{2,}\b
+
 # acceptable duplicates
 # ls directory listings
 [-bcdlpsw](?:[-r][-w][-sx]){3}\s+\d+\s+(\S+)\s+\g{-1}\s+\d+\s+
 # C/idl types + English ...
 \s(Guid|long|LONG|that) \g{-1}\s
+
 # javadoc / .net
-(?:\@(?:groupname|param)|(?:public|private)(?:\s+static|\s+readonly)*)\s+(\w+)\s+\g{-1}\s
+(?:[\\@](?:groupname|param)|(?:public|private)(?:\s+static|\s+readonly)*)\s+(\w+)\s+\g{-1}\s
+
+# Commit message -- Signed-off-by and friends
+^\s*(?:(?:Based-on-patch|Co-authored|Helped|Mentored|Reported|Reviewed|Signed-off)-by|Thanks-to): (?:[^<]*<[^>]*>|[^<]*)\s*$
+
+# Autogenerated revert commit message
+^This reverts commit [0-9a-f]{40}\.$
+
 # vtmode
 --vtmode\s+(\w+)\s+\g{-1}\s
 

.github/actions/spelling/reject.txt

@@ -1,31 +1,12 @@
-benefitting
-occurences?
-Sorce
 ^attache$
 ^attacher$
 ^attachers$
+benefitting
+occurences?
 ^dependan.*
 ^oer$
-^spae$
-^spae-man$
-^spaebook$
-^spaecraft$
-^spaed$
-^spaedom$
-^spaeing$
-^spaeings$
-^spaeman$
-^spaer$
-^Spaerobee$
-^spaes$
-^spaewife$
-^spaewoman$
-^spaework$
-^spaewright$
+Sorce
+^[Ss]pae.*
 ^untill$
 ^untilling$
-^wether$
 ^wether.*
-^wethers$
-^wetherteg$
-^[Ss]pae.*

.github/workflows/spelling2.yml

@@ -1,10 +1,57 @@
 # spelling.yml is blocked per https://github.com/check-spelling/check-spelling/security/advisories/GHSA-g86g-chm8-7r2p
 name: Spell checking
+
+# Comment management is handled through a secondary job, for details see:
+# https://github.com/check-spelling/check-spelling/wiki/Feature%3A-Restricted-Permissions
+#
+# `jobs.comment-push` runs when a push is made to a repository and the `jobs.spelling` job needs to make a comment
+#   (in odd cases, it might actually run just to collapse a commment, but that's fairly rare)
+#   it needs `contents: write` in order to add a comment.
+#
+# `jobs.comment-pr` runs when a pull_request is made to a repository and the `jobs.spelling` job needs to make a comment
+#   or collapse a comment (in the case where it had previously made a comment and now no longer needs to show a comment)
+#   it needs `pull-requests: write` in order to manipulate those comments.
+
+# Updating pull request branches is managed via comment handling.
+# For details, see: https://github.com/check-spelling/check-spelling/wiki/Feature:-Update-expect-list
+#
+# These elements work together to make it happen:
+#
+# `on.issue_comment`
+#   This event listens to comments by users asking to update the metadata.
+#
+# `jobs.update`
+#   This job runs in response to an issue_comment and will push a new commit
+#   to update the spelling metadata.
+#
+# `with.experimental_apply_changes_via_bot`
+#   Tells the action to support and generate messages that enable it
+#   to make a commit to update the spelling metadata.
+#
+# `with.ssh_key`
+#   In order to trigger workflows when the commit is made, you can provide a
+#   secret (typically, a write-enabled github deploy key).
+#
+#   For background, see: https://github.com/check-spelling/check-spelling/wiki/Feature:-Update-with-deploy-key
+
 on:
-  pull_request_target:
   push:
-    branches: ["**"]
-    tags-ignore: ["**"]
+    branches:
+    - "**"
+    tags-ignore:
+    - "**"
+  pull_request_target:
+    branches:
+    - "**"
+    tags-ignore:
+    - "**"
+    types:
+    - 'opened'
+    - 'reopened'
+    - 'synchronize'
+  issue_comment:
+    types:
+    - 'created'
 
 jobs:
   spelling:
@@ -24,23 +71,64 @@ jobs:
     steps:
     - name: check-spelling
       id: spelling
-      uses: check-spelling/check-spelling@v0.0.20
+      uses: check-spelling/check-spelling@v0.0.21
       with:
         suppress_push_for_open_pull_request: 1
         checkout: true
+        check_file_names: 1
+        spell_check_this: check-spelling/spell-check-this@prerelease
         post_comment: 0
+        use_magic_file: 1
+        extra_dictionary_limit: 10
+        extra_dictionaries:
+          cspell:software-terms/src/software-terms.txt
+          cspell:python/src/python/python-lib.txt
+          cspell:node/node.txt
+          cspell:cpp/src/stdlib-c.txt
+          cspell:cpp/src/stdlib-cpp.txt
+          cspell:fullstack/fullstack.txt
+          cspell:filetypes/filetypes.txt
+          cspell:html/html.txt
+          cspell:cpp/src/compiler-msvc.txt
+          cspell:python/src/common/extra.txt
+          cspell:powershell/powershell.txt
+          cspell:aws/aws.txt
+          cspell:cpp/src/lang-keywords.txt
+          cspell:npm/npm.txt
+          cspell:dotnet/dotnet.txt
+          cspell:python/src/python/python.txt
+          cspell:css/css.txt
+          cspell:cpp/src/stdlib-cmath.txt
+        check_extra_dictionaries: ''
 
-  comment:
-    name: Report
+  comment-push:
+    name: Report (Push)
+    # If your workflow isn't running on push, you can remove this job
     runs-on: ubuntu-latest
     needs: spelling
     permissions:
       contents: write
-      pull-requests: write
-    if: (success() || failure()) && needs.spelling.outputs.followup && github.event_name != 'push'
+    if: (success() || failure()) && needs.spelling.outputs.followup && github.event_name == 'push'
     steps:
     - name: comment
-      uses: check-spelling/check-spelling@v0.0.20
+      uses: check-spelling/check-spelling@v0.0.21
       with:
         checkout: true
+        spell_check_this: check-spelling/spell-check-this@prerelease
+        task: ${{ needs.spelling.outputs.followup }}
+
+  comment-pr:
+    name: Report (PR)
+    # If you workflow isn't running on pull_request*, you can remove this job
+    runs-on: ubuntu-latest
+    needs: spelling
+    permissions:
+      pull-requests: write
+    if: (success() || failure()) && needs.spelling.outputs.followup && contains(github.event_name, 'pull_request')
+    steps:
+    - name: comment
+      uses: check-spelling/check-spelling@v0.0.21
+      with:
+        checkout: true
+        spell_check_this: check-spelling/spell-check-this@prerelease
         task: ${{ needs.spelling.outputs.followup }}

scratch/ScratchIslandApp/Package/Package.wapproj

@@ -136,12 +136,12 @@
   <!-- **END VC LIBS HACK** -->
 
   <!-- This is required to get the package dependency in the AppXManifest. -->
-  <Import Project="..\..\..\packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets" Condition="Exists('..\..\..\packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets')" />
+  <Import Project="..\..\..\packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets" Condition="Exists('..\..\..\packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets')" />
   <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
     <PropertyGroup>
       <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
     </PropertyGroup>
-    <Error Condition="!Exists('..\..\..\packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets')" Text="$([System.String]::Format('$(ErrorText)', '..\..\..\packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets'))" />
+    <Error Condition="!Exists('..\..\..\packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets')" Text="$([System.String]::Format('$(ErrorText)', '..\..\..\packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets'))" />
   </Target>
 
 

scratch/ScratchIslandApp/SampleApp/MyPage.cpp

@@ -3,9 +3,11 @@
 
 #include "pch.h"
 #include "MyPage.h"
+#include "MySettings.h"
 #include <LibraryResources.h>
 #include "MyPage.g.cpp"
-#include "MySettings.h"
+#include "..\..\..\src\cascadia\UnitTests_Control\MockControlSettings.h"
+#include "..\..\..\src\types\inc\utils.hpp"
 
 using namespace std::chrono_literals;
 using namespace winrt::Microsoft::Terminal;
@@ -26,7 +28,7 @@ namespace winrt::SampleApp::implementation
 
     void MyPage::Create()
     {
-        auto settings = winrt::make_self<implementation::MySettings>();
+        auto settings = winrt::make_self<MySettings>();
 
         auto connectionSettings{ TerminalConnection::ConptyConnection::CreateSettings(L"cmd.exe /k echo This TermControl is hosted in-proc...",
                                                                                       winrt::hstring{},
@@ -44,6 +46,216 @@ namespace winrt::SampleApp::implementation
         Control::TermControl control{ *settings, *settings, conn };
 
         InProcContent().Children().Append(control);
+
+        // Once the control loads (and not before that), write some text for debugging:
+        control.Initialized([conn](auto&&, auto&&) {
+            conn.WriteInput(L"This TermControl is hosted in-proc...");
+        });
+    }
+
+    static wil::unique_process_information _createHostClassProcess(const winrt::guid& g)
+    {
+        auto guidStr{ ::Microsoft::Console::Utils::GuidToString(g) };
+
+        // Create an event that the content process will use to signal it is
+        // ready to go. We won't need the event after this function, so the
+        // unique_event will clean up our handle when we leave this scope. The
+        // ContentProcess is responsible for cleaning up its own handle.
+        wil::unique_event ev{ CreateEvent(nullptr, true, false, nullptr) };
+        // Make sure to mark this handle as inheritable! Even with
+        // bInheritHandles=true, this is only inherited when it's explicitly
+        // allowed to be.
+        SetHandleInformation(ev.get(), HANDLE_FLAG_INHERIT, 1);
+
+        // god bless, fmt::format will format a HANDLE like `0xa80`
+        std::wstring commandline{
+            fmt::format(L"WindowsTerminal.exe --content {} --signal {}", guidStr, ev.get())
+        };
+
+        STARTUPINFO siOne{ 0 };
+        siOne.cb = sizeof(STARTUPINFOW);
+        wil::unique_process_information piOne;
+        auto succeeded = CreateProcessW(
+            nullptr,
+            commandline.data(),
+            nullptr, // lpProcessAttributes
+            nullptr, // lpThreadAttributes
+            true, // bInheritHandles
+            CREATE_UNICODE_ENVIRONMENT, // dwCreationFlags
+            nullptr, // lpEnvironment
+            nullptr, // startingDirectory
+            &siOne, // lpStartupInfo
+            &piOne // lpProcessInformation
+        );
+        THROW_IF_WIN32_BOOL_FALSE(succeeded);
+
+        // Wait for the child process to signal that they're ready.
+        WaitForSingleObject(ev.get(), INFINITE);
+
+        return piOne;
+    }
+
+    winrt::fire_and_forget MyPage::_writeToLog(std::wstring_view str)
+    {
+        winrt::hstring copy{ str };
+        // Switch back to the UI thread.
+        co_await resume_foreground(Dispatcher());
+        winrt::WUX::Controls::TextBlock block;
+        block.Text(copy);
+        Log().Children().Append(block);
+    }
+
+    winrt::fire_and_forget MyPage::CreateClicked(const IInspectable& sender,
+                                                 const WUX::Input::TappedRoutedEventArgs& eventArgs)
+    {
+        auto guidString = GuidInput().Text();
+
+        // Capture calling context.
+        winrt::apartment_context ui_thread;
+
+        auto canConvert = guidString.size() == 38 &&
+                          guidString.front() == '{' &&
+                          guidString.back() == '}';
+        bool tryingToAttach = false;
+        winrt::guid contentGuid{ ::Microsoft::Console::Utils::CreateGuid() };
+
+        if (canConvert)
+        {
+            GUID result{};
+            if (SUCCEEDED(IIDFromString(guidString.c_str(), &result)))
+            {
+                contentGuid = result;
+                tryingToAttach = true;
+            }
+        }
+        _writeToLog(tryingToAttach ? L"Attaching to existing content process" : L"Creating new content process");
+
+        co_await winrt::resume_background();
+        if (!tryingToAttach)
+        {
+            // Spawn a wt.exe, with the guid on the commandline
+            piContentProcess = std::move(_createHostClassProcess(contentGuid));
+        }
+
+        // THIS MUST TAKE PLACE AFTER _createHostClassProcess.
+        // * If we're creating a new OOP control, _createHostClassProcess will
+        //   spawn the process that will actually host the ContentProcess
+        //   object.
+        // * If we're attaching, then that process already exists.
+        Control::ContentProcess content{ nullptr };
+        try
+        {
+            content = create_instance<Control::ContentProcess>(contentGuid, CLSCTX_LOCAL_SERVER);
+        }
+        catch (winrt::hresult_error hr)
+        {
+            _writeToLog(L"CreateInstance the ContentProcess object");
+            _writeToLog(fmt::format(L"    HR ({}): {}", hr.code(), hr.message().c_str()));
+            co_return; // be sure to co_return or we'll fall through to the part where we clear the log
+        }
+
+        if (content == nullptr)
+        {
+            _writeToLog(L"Failed to connect to the ContentProcess object. It may not have been started fast enough.");
+            co_return; // be sure to co_return or we'll fall through to the part where we clear the log
+        }
+
+        TerminalConnection::ConnectionInformation connectInfo{ nullptr };
+        Control::IControlSettings settings{ *winrt::make_self<implementation::MySettings>() };
+
+        // When creating a terminal for the first time, pass it a connection
+        // info
+        //
+        // otherwise, when attaching to an existing one, just pass null, because
+        // we don't need the connection info.
+        if (!tryingToAttach)
+        {
+            auto connectionSettings{ TerminalConnection::ConptyConnection::CreateSettings(L"cmd.exe /k echo This TermControl is hosted out-of-proc...",
+                                                                                          winrt::hstring{},
+                                                                                          L"",
+                                                                                          nullptr,
+                                                                                          32,
+                                                                                          80,
+                                                                                          winrt::guid()) };
+
+            // "Microsoft.Terminal.TerminalConnection.ConptyConnection"
+            winrt::hstring myClass{ winrt::name_of<TerminalConnection::ConptyConnection>() };
+            connectInfo = TerminalConnection::ConnectionInformation(myClass, connectionSettings);
+
+            if (!content.Initialize(settings, settings, connectInfo))
+            {
+                _writeToLog(L"Failed to Initialize the ContentProcess object.");
+                co_return; // be sure to co_return or we'll fall through to the part where we clear the log
+            }
+        }
+        else
+        {
+            // If we're attaching, we don't really need to do anything special.
+        }
+
+        // Switch back to the UI thread.
+        co_await ui_thread;
+
+        // Create the XAML control that will be attached to the content process.
+        // We're not passing in a connection, because the contentGuid will be used instead.
+        Control::TermControl control{ contentGuid, settings, settings, nullptr };
+        auto weakControl = winrt::make_weak(control);
+        control.RaiseNotice([this](auto&&, auto& args) {
+            _writeToLog(L"Content process died, probably.");
+            _writeToLog(args.Message());
+            OutOfProcContent().Children().Clear();
+            GuidInput().Text(L"");
+            if (piContentProcess.hProcess)
+            {
+                piContentProcess.reset();
+            }
+        });
+        control.ConnectionStateChanged([this, weakControl](auto&&, auto&) {
+            if (auto strongControl{ weakControl.get() })
+            {
+                const auto newConnectionState = strongControl.ConnectionState();
+                if (newConnectionState == TerminalConnection::ConnectionState::Closed)
+                {
+                    _writeToLog(L"Connection was closed");
+                    OutOfProcContent().Children().Clear();
+                    GuidInput().Text(L"");
+                    if (piContentProcess.hProcess)
+                    {
+                        piContentProcess.reset();
+                    }
+                }
+            }
+        });
+
+        Log().Children().Clear();
+        OutOfProcContent().Children().Append(control);
+
+        if (!tryingToAttach)
+        {
+            auto guidStr{ ::Microsoft::Console::Utils::GuidToString(contentGuid) };
+            GuidInput().Text(guidStr);
+        }
+    }
+
+    void MyPage::CloseClicked(const IInspectable& /*sender*/,
+                              const WUX::Input::TappedRoutedEventArgs& /*eventArgs*/)
+    {
+        OutOfProcContent().Children().Clear();
+        GuidInput().Text(L"");
+        if (piContentProcess.hProcess)
+        {
+            piContentProcess.reset();
+        }
+    }
+
+    void MyPage::KillClicked(const IInspectable& /*sender*/,
+                             const WUX::Input::TappedRoutedEventArgs& /*eventArgs*/)
+    {
+        if (piContentProcess.hProcess)
+        {
+            TerminateProcess(piContentProcess.hProcess, (UINT)-1);
+            piContentProcess.reset();
+        }
     }
 
     // Method Description:

scratch/ScratchIslandApp/SampleApp/MyPage.h

@@ -14,11 +14,18 @@ namespace winrt::SampleApp::implementation
         MyPage();
 
         void Create();
-
         hstring Title();
 
+        winrt::fire_and_forget CreateClicked(const IInspectable& sender, const Windows::UI::Xaml::Input::TappedRoutedEventArgs& eventArgs);
+        void CloseClicked(const IInspectable& sender, const Windows::UI::Xaml::Input::TappedRoutedEventArgs& eventArgs);
+        void KillClicked(const IInspectable& sender, const Windows::UI::Xaml::Input::TappedRoutedEventArgs& eventArgs);
+
     private:
         friend struct MyPageT<MyPage>; // for Xaml to bind events
+
+        wil::unique_process_information piContentProcess;
+
+        winrt::fire_and_forget _writeToLog(std::wstring_view str);
     };
 }
 

scratch/ScratchIslandApp/SampleApp/MyPage.xaml

@@ -23,9 +23,23 @@
             <TextBox x:Name="GuidInput"
                      Width="400"
                      PlaceholderText="{}{guid here}" />
-            <Button Grid.Row="0">
+            <Button x:Name="CreateOutOfProcControl"
+                    Grid.Row="0"
+                    Tapped="CreateClicked">
                 Create
             </Button>
+            <Button x:Name="CloseOutOfProcControl"
+                    Grid.Row="0"
+                    Margin="4,0,0,0"
+                    Tapped="CloseClicked">
+                Close
+            </Button>
+            <Button x:Name="KillOutOfProcControl"
+                    Grid.Row="0"
+                    Margin="4,0,0,0"
+                    Tapped="KillClicked">
+                Kill
+            </Button>
 
         </StackPanel>
 
@@ -46,14 +60,26 @@
                   VerticalAlignment="Stretch"
                   Background="#ff0000" />
 
-            <Grid x:Name="OutOfProcContent"
-                  Grid.Column="1"
-                  Padding="16"
+            <Grid Grid.Column="1"
                   HorizontalAlignment="Stretch"
-                  VerticalAlignment="Stretch"
-                  Background="#0000ff" />
+                  VerticalAlignment="Stretch">
 
+                <Grid.RowDefinitions>
+                    <RowDefinition Height="Auto" />
+                    <RowDefinition Height="*" />
+                </Grid.RowDefinitions>
 
+                <StackPanel x:Name="Log"
+                            Grid.Row="0"
+                            Orientation="Vertical" />
+
+                <Grid x:Name="OutOfProcContent"
+                      Grid.Row="1"
+                      Padding="16"
+                      HorizontalAlignment="Stretch"
+                      VerticalAlignment="Stretch"
+                      Background="#0000ff" />
+            </Grid>
 
         </Grid>
 

scratch/ScratchIslandApp/SampleApp/SampleAppLib.vcxproj

@@ -156,12 +156,12 @@
   <!-- This -must- go after cppwinrt.build.post.props because that includes many VS-provided props including appcontainer.common.props, which stomps on what cppwinrt.targets did. -->
   <Import Project="$(OpenConsoleDir)src\common.nugetversions.targets" />
 
-  <Import Project="$(OpenConsoleDir)packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets" Condition="Exists('$(OpenConsoleDir)packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets')" />
+  <Import Project="$(OpenConsoleDir)packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets" Condition="Exists('$(OpenConsoleDir)packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets')" />
   <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
     <PropertyGroup>
       <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
     </PropertyGroup>
-    <Error Condition="!Exists('$(OpenConsoleDir)packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(OpenConsoleDir)\packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets'))" />
+    <Error Condition="!Exists('$(OpenConsoleDir)packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(OpenConsoleDir)\packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets'))" />
   </Target>
 
   <!--

scratch/ScratchIslandApp/SampleApp/dll/SampleApp.vcxproj

@@ -91,12 +91,12 @@
     </Link>
   </ItemDefinitionGroup>
 
-  <Import Project="$(OpenConsoleDir)packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets" Condition="Exists('$(OpenConsoleDir)packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets')" />
+  <Import Project="$(OpenConsoleDir)packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets" Condition="Exists('$(OpenConsoleDir)packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets')" />
   <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
     <PropertyGroup>
       <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
     </PropertyGroup>
-    <Error Condition="!Exists('$(OpenConsoleDir)\packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(OpenConsoleDir)\packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets'))" />
+    <Error Condition="!Exists('$(OpenConsoleDir)\packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(OpenConsoleDir)\packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets'))" />
   </Target>
 
   <ItemDefinitionGroup>

scratch/ScratchIslandApp/WindowExe/SampleIslandWindow.cpp

@@ -57,8 +57,8 @@ void SampleIslandWindow::MakeWindow() noexcept
                                 WS_OVERLAPPEDWINDOW,
                                 CW_USEDEFAULT,
                                 CW_USEDEFAULT,
-                                CW_USEDEFAULT,
-                                CW_USEDEFAULT,
+                                1024,
+                                860,
                                 nullptr,
                                 nullptr,
                                 wc.hInstance,

scratch/ScratchIslandApp/WindowExe/WindowExe.vcxproj

@@ -144,12 +144,12 @@
 
   <Import Project="$(OpenConsoleDir)src\cppwinrt.build.post.props" />
 
-  <Import Project="..\..\..\packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets" Condition="Exists('..\..\..\packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets')" />
+  <Import Project="..\..\..\packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets" Condition="Exists('..\..\..\packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets')" />
   <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
     <PropertyGroup>
       <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
     </PropertyGroup>
-    <Error Condition="!Exists('..\..\..\packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets')" Text="$([System.String]::Format('$(ErrorText)', '..\..\..\packages\Microsoft.UI.Xaml.2.7.1\build\native\Microsoft.UI.Xaml.targets'))" />
+    <Error Condition="!Exists('..\..\..\packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets')" Text="$([System.String]::Format('$(ErrorText)', '..\..\..\packages\Microsoft.UI.Xaml.2.7.3-prerelease.220816001\build\native\Microsoft.UI.Xaml.targets'))" />
   </Target>
 
   <!-- Override GetPackagingOutputs to roll up all our dependencies.

src/cascadia/TerminalConnection/ConnectionInformation.cpp

@@ -25,6 +25,13 @@ namespace winrt::Microsoft::Terminal::TerminalConnection::implementation
     TerminalConnection::ITerminalConnection ConnectionInformation::CreateConnection(TerminalConnection::ConnectionInformation info)
     try
     {
+        // pilfered from `winrt_get_activation_factory` in module.g.cpp. Does a
+        // reverse string match, so that we check the classname first, skipping
+        // the namespace prefixes.
+        static auto requal = [](std::wstring_view const& left, std::wstring_view const& right) noexcept -> bool {
+            return std::equal(left.rbegin(), left.rend(), right.rbegin(), right.rend());
+        };
+
         Windows::Foundation::IInspectable inspectable{};
 
         const auto name = static_cast<HSTRING>(winrt::get_abi(info.ClassName()));
@@ -36,21 +43,58 @@ namespace winrt::Microsoft::Terminal::TerminalConnection::implementation
         auto raw = reinterpret_cast<::IInspectable**>(pointer);
 #pragma warning(pop)
 
-        // RoActivateInstance() will try to create an instance of the object,
-        // who's fully qualified name is the string in Name().
+        TerminalConnection::ITerminalConnection connection{ nullptr };
+
+        // A couple short-circuits, for connections that _we_ implement.
+        // Sometimes, RoActivateInstance is weird and fails with errors like the
+        // following:
         //
-        // The class has to be activatable. For the Terminal, this is easy
-        // enough - we're not hosting anything that's not already in our
-        // manifest, or living as a .dll & .winmd SxS.
+        /*
+        onecore\com\combase\inc\RegistryKey.hpp(527)\combase.dll!01234:
+        (caller: 01234) LogHr(2) tid(83a8) 800700A1 The specified
+        path is invalid.
+            Msg:[StaticNtOpen failed with
+            path:\REGISTRY\A\{A41685A4-AD85-4C4C-BA5D-A849ADBF3C40}\ActivatableClassId
+            \REGISTRY\MACHINE\Software\Classes\ActivatableClasses]
+        ...\src\cascadia\TerminalConnection\ConnectionInformation.cpp(47)\TerminalConnection.dll!01234:
+        (caller: 01234) LogHr(1) tid(83a8) 800700A1 The specified
+        path is invalid.
+            [...TerminalConnection::implementation::ConnectionInformation::CreateConnection(RoActivateInstance(name,
+            raw))]
+        */
         //
-        // When we get to extensions (GH#4000), we may want to revisit.
-        if (LOG_IF_FAILED(RoActivateInstance(name, raw)))
+        // So to avoid those, we'll manually instantiate these
+        if (requal(info.ClassName(), winrt::name_of<TerminalConnection::ConptyConnection>()))
         {
-            return nullptr;
+            connection = TerminalConnection::ConptyConnection();
+        }
+        else if (requal(info.ClassName(), winrt::name_of<TerminalConnection::AzureConnection>()))
+        {
+            connection = TerminalConnection::AzureConnection();
+        }
+        else if (requal(info.ClassName(), winrt::name_of<TerminalConnection::EchoConnection>()))
+        {
+            connection = TerminalConnection::EchoConnection();
+        }
+        else
+        {
+            // RoActivateInstance() will try to create an instance of the object,
+            // who's fully qualified name is the string in Name().
+            //
+            // The class has to be activatable. For the Terminal, this is easy
+            // enough - we're not hosting anything that's not already in our
+            // manifest, or living as a .dll & .winmd SxS.
+            //
+            // When we get to extensions (GH#4000), we may want to revisit.
+            if (LOG_IF_FAILED(RoActivateInstance(name, raw)))
+            {
+                return nullptr;
+            }
+            connection = inspectable.try_as<TerminalConnection::ITerminalConnection>();
         }
 
         // Now that thing we made, make sure it's actually a ITerminalConnection
-        if (const auto connection{ inspectable.try_as<TerminalConnection::ITerminalConnection>() })
+        if (connection)
         {
             // Initialize it, and return it.
             connection.Initialize(info.Settings());

src/cascadia/TerminalControl/ContentProcess.cpp

@@ -0,0 +1,114 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
+#include "pch.h"
+#include "ContentProcess.h"
+#include "ContentProcess.g.cpp"
+
+namespace winrt::Microsoft::Terminal::Control::implementation
+{
+    ContentProcess::ContentProcess() :
+        _ourPID{ GetCurrentProcessId() } {}
+
+    bool ContentProcess::Initialize(Control::IControlSettings settings,
+                                    Control::IControlAppearance unfocusedAppearance,
+                                    TerminalConnection::ConnectionInformation connectionInfo)
+    {
+        auto conn{ TerminalConnection::ConnectionInformation::CreateConnection(connectionInfo) };
+        if (conn == nullptr)
+        {
+            return false;
+        }
+        _interactivity = winrt::make<implementation::ControlInteractivity>(settings, unfocusedAppearance, conn);
+        return true;
+    }
+
+// C4722 - destructor never returns, potential memory leak
+// We're just exiting the whole process, so I think we're okay, thanks.
+#pragma warning(push)
+#pragma warning(disable : 4722)
+    ContentProcess::~ContentProcess()
+    {
+        // DANGER - We're straight up going to EXIT THE ENTIRE PROCESS when we
+        // get destructed. This eliminates the need to do any sort of
+        // ref-counting weirdness. This entire process exists to host one
+        // singular ContentProcess instance. When we're destructed, it's because
+        // every other window process was done with us. We can die now, knowing
+        // that our job is complete.
+
+        std::exit(0);
+    }
+#pragma warning(pop)
+
+    Control::ControlInteractivity ContentProcess::GetInteractivity()
+    {
+        return _interactivity;
+    }
+
+    uint64_t ContentProcess::GetPID()
+    {
+        return _ourPID;
+    }
+
+    // Method Description:
+    // - Duplicate the swap chain handle to the provided process.
+    // - If the provided PID is our pid, then great - we don't need to do anything.
+    // Arguments:
+    // - callersPid: the PID of the process calling this method.
+    // Return Value:
+    // - The value of the swapchain handle in the callers process
+    // Notes:
+    // - This is BODGY! We're basically asking to marshal a HANDLE here. WinRT
+    //   has no good mechanism for doing this, so we're doing it by casting the
+    //   value to a uint64_t. In all reality, we _should_ be using a COM
+    //   interface for this, because it can set up the security on these handles
+    //   more appropriately. Fortunately, all we're dealing with is swapchains,
+    //   so the security doesn't matter all that much.
+    uint64_t ContentProcess::RequestSwapChainHandle(const uint64_t callersPid)
+    {
+        auto ourPid = GetCurrentProcessId();
+        HANDLE ourHandle = reinterpret_cast<HANDLE>(_interactivity.Core().SwapChainHandle());
+        if (callersPid == ourPid)
+        {
+            return reinterpret_cast<uint64_t>(ourHandle);
+        }
+
+        wil::unique_handle hWindowProcess{ OpenProcess(PROCESS_ALL_ACCESS,
+                                                       FALSE,
+                                                       static_cast<DWORD>(callersPid)) };
+        if (hWindowProcess.get() == nullptr)
+        {
+            TraceLoggingWrite(g_hTerminalControlProvider,
+                              "ContentProcess::RequestSwapChainHandle_OpenOtherProcessFailed",
+                              TraceLoggingLevel(WINEVENT_LEVEL_VERBOSE),
+                              TraceLoggingKeyword(TIL_KEYWORD_TRACE));
+
+            LOG_LAST_ERROR();
+            return 0;
+        }
+
+        HANDLE theirHandle{ nullptr };
+        BOOL success = DuplicateHandle(GetCurrentProcess(),
+                                       ourHandle,
+                                       hWindowProcess.get(),
+                                       &theirHandle,
+                                       0,
+                                       FALSE,
+                                       DUPLICATE_SAME_ACCESS);
+        if (!success)
+        {
+            TraceLoggingWrite(g_hTerminalControlProvider,
+                              "ContentProcess::RequestSwapChainHandle_DuplicateHandleFailed",
+                              TraceLoggingLevel(WINEVENT_LEVEL_VERBOSE),
+                              TraceLoggingKeyword(TIL_KEYWORD_TRACE));
+
+            LOG_LAST_ERROR();
+            return 0;
+        }
+
+        // At this point, the handle is now in their process space, with value
+        // theirHandle
+        return reinterpret_cast<uint64_t>(theirHandle);
+    }
+
+}

src/cascadia/TerminalControl/ContentProcess.h

@@ -0,0 +1,33 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
+#pragma once
+
+#include "ContentProcess.g.h"
+#include "ControlInteractivity.h"
+
+namespace winrt::Microsoft::Terminal::Control::implementation
+{
+    struct ContentProcess : ContentProcessT<ContentProcess>
+    {
+        ContentProcess();
+        ~ContentProcess();
+
+        bool Initialize(Control::IControlSettings settings,
+                        Control::IControlAppearance unfocusedAppearance,
+                        TerminalConnection::ConnectionInformation connectionInfo);
+        Control::ControlInteractivity GetInteractivity();
+
+        uint64_t GetPID();
+        uint64_t RequestSwapChainHandle(const uint64_t pid);
+
+    private:
+        Control::ControlInteractivity _interactivity{ nullptr };
+        uint64_t _ourPID;
+    };
+}
+
+namespace winrt::Microsoft::Terminal::Control::factory_implementation
+{
+    BASIC_FACTORY(ContentProcess);
+}

src/cascadia/TerminalControl/ContentProcess.idl

@@ -0,0 +1,22 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
+import "ControlInteractivity.idl";
+
+namespace Microsoft.Terminal.Control
+{
+    runtimeclass ContentProcess {
+
+        ContentProcess();
+
+        Boolean Initialize(IControlSettings settings,
+                           IControlAppearance unfocusedAppearance,
+                           Microsoft.Terminal.TerminalConnection.ConnectionInformation connectionInfo);
+
+        ControlInteractivity GetInteractivity();
+
+        UInt64 GetPID();
+
+        UInt64 RequestSwapChainHandle(UInt64 pid);
+    };
+}

src/cascadia/TerminalControl/ControlCore.cpp

@@ -2017,6 +2017,11 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         return Opacity() < 1.0f || UseAcrylic() || !_settings->BackgroundImage().empty() || _settings->UseBackgroundImageForWindow();
     }
 
+    double ControlCore::DisplayScale() const
+    {
+        return _compositionScale;
+    }
+
     uint64_t ControlCore::OwningHwnd()
     {
         return _owningHwnd;

src/cascadia/TerminalControl/ControlCore.h

@@ -75,6 +75,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
         void SizeChanged(const double width, const double height);
         void ScaleChanged(const double scale);
+        double DisplayScale() const;
         uint64_t SwapChainHandle() const;
 
         void AdjustFontSize(int fontSizeDelta);
@@ -332,6 +333,9 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         inline bool _IsClosing() const noexcept
         {
 #ifndef NDEBUG
+            // This may not be strictly true if the core is running out of proc
+            // with XAML. This assert was hit frequently during initial x-proc
+            // development, but seemingly not anymore. Keep an eye on it.
             if (_dispatcher)
             {
                 // _closing isn't atomic and may only be accessed from the main thread.

src/cascadia/TerminalControl/ControlCore.idl

@@ -77,6 +77,7 @@ namespace Microsoft.Terminal.Control
         Boolean HasUnfocusedAppearance();
 
         UInt64 SwapChainHandle { get; };
+        Double DisplayScale { get; };
 
         Windows.Foundation.Size FontSize { get; };
         String FontFaceName { get; };

src/cascadia/TerminalControl/InteractivityAutomationPeer.cpp

@@ -43,7 +43,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     {
         _controlPadding = til::rect{ til::math::rounding, padding };
     }
-    void InteractivityAutomationPeer::ParentProvider(AutomationPeer parentProvider)
+    void InteractivityAutomationPeer::ParentProvider(const Windows::UI::Xaml::Automation::Provider::IRawElementProviderSimple& parentProvider)
     {
         _parentProvider = parentProvider;
     }
@@ -171,7 +171,11 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
     double InteractivityAutomationPeer::GetScaleFactor() const noexcept
     {
-        return DisplayInformation::GetForCurrentView().RawPixelsPerViewPixel();
+        // If we were being used in a process that had a CoreWindow, we could just call
+        //  DisplayInformation::GetForCurrentView().RawPixelsPerViewPixel();
+        //
+        // We won't always be though, so instead, ask our model what the DPI is.
+        return _interactivity->Core().DisplayScale();
     }
 
     void InteractivityAutomationPeer::ChangeViewport(const til::inclusive_rect& NewWindow)
@@ -182,15 +186,12 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
     XamlAutomation::ITextRangeProvider InteractivityAutomationPeer::_CreateXamlUiaTextRange(UIA::ITextRangeProvider* returnVal) const
     {
-        // LOAD-BEARING: use _parentProvider->ProviderFromPeer(_parentProvider) instead of this->ProviderFromPeer(*this).
-        // Since we split the automation peer into TermControlAutomationPeer and InteractivityAutomationPeer,
-        // using "this" returns null. This can cause issues with some UIA Client scenarios like any navigation in Narrator.
-        const auto parent{ _parentProvider.get() };
-        if (!parent)
+        if (!_parentProvider)
         {
             return nullptr;
         }
-        const auto xutr = winrt::make_self<XamlUiaTextRange>(returnVal, parent.ProviderFromPeer(parent));
+
+        const auto xutr = winrt::make_self<XamlUiaTextRange>(returnVal, _parentProvider);
         return xutr.as<XamlAutomation::ITextRangeProvider>();
     };
 

src/cascadia/TerminalControl/InteractivityAutomationPeer.h

@@ -43,7 +43,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
         void SetControlBounds(const Windows::Foundation::Rect bounds);
         void SetControlPadding(const Core::Padding padding);
-        void ParentProvider(Windows::UI::Xaml::Automation::Peers::AutomationPeer parentProvider);
+        void ParentProvider(const Windows::UI::Xaml::Automation::Provider::IRawElementProviderSimple& parentProvider);
 
 #pragma region IUiaEventDispatcher
         void SignalSelectionChanged() override;
@@ -81,7 +81,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
         ::Microsoft::WRL::ComPtr<::Microsoft::Terminal::TermControlUiaProvider> _uiaProvider;
         winrt::Microsoft::Terminal::Control::implementation::ControlInteractivity* _interactivity;
-        weak_ref<Windows::UI::Xaml::Automation::Peers::AutomationPeer> _parentProvider;
+        winrt::Windows::UI::Xaml::Automation::Provider::IRawElementProviderSimple _parentProvider{ nullptr };
 
         til::rect _controlBounds{};
         til::rect _controlPadding{};

src/cascadia/TerminalControl/InteractivityAutomationPeer.idl

@@ -3,13 +3,11 @@
 namespace Microsoft.Terminal.Control
 {
     [default_interface] runtimeclass InteractivityAutomationPeer :
-        Windows.UI.Xaml.Automation.Peers.AutomationPeer,
         Windows.UI.Xaml.Automation.Provider.ITextProvider
     {
-
         void SetControlBounds(Windows.Foundation.Rect bounds);
         void SetControlPadding(Microsoft.Terminal.Core.Padding padding);
-        void ParentProvider(Windows.UI.Xaml.Automation.Peers.AutomationPeer parentProvider);
+        void ParentProvider(Windows.UI.Xaml.Automation.Provider.IRawElementProviderSimple provider);
 
         event Windows.Foundation.TypedEventHandler<Object, Object> SelectionChanged;
         event Windows.Foundation.TypedEventHandler<Object, Object> TextChanged;

src/cascadia/TerminalControl/Resources/en-US/Resources.resw

@@ -208,4 +208,10 @@ Please either install the missing font or choose another one.</value>
     <value>No results found</value>
     <comment>Announced to a screen reader when the user searches for some text and there are no matches for that text in the terminal.</comment>
   </data>
+  <data name="TermControl_ContentDiedTextBlock.Text" xml:space="preserve">
+    <value>The content of this terminal was closed unexpectedly.</value>
+  </data>
+  <data name="TermControl_ContentDiedButton.Content" xml:space="preserve">
+    <value>Close</value>
+  </data>
 </root>

src/cascadia/TerminalControl/TermControl.cpp

@@ -1,5 +1,8 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT license.
+//
+// The functions for handling content processes in the TermControl are largely
+// in TermControlContentManagement.cpp
 
 #include "pch.h"
 #include "TermControl.h"
@@ -31,8 +34,10 @@ using namespace winrt::Windows::ApplicationModel::DataTransfer;
 // The updates are throttled to limit power usage.
 constexpr const auto ScrollBarUpdateInterval = std::chrono::milliseconds(8);
 
-// The minimum delay between updating the TSF input control.
-// This is already throttled primarily in the ControlCore, with a timeout of 100ms. We're adding another smaller one here, as the (potentially x-proc) call will come in off the UI thread
+// The minimum delay between updating the TSF input control. This is already
+// throttled primarily in the ControlCore, with a timeout of 100ms. We're adding
+// another smaller one here, as the (potentially x-proc) call will come in off
+// the UI thread
 constexpr const auto TsfRedrawInterval = std::chrono::milliseconds(8);
 
 // The minimum delay between updating the locations of regex patterns
@@ -50,6 +55,14 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     TermControl::TermControl(IControlSettings settings,
                              Control::IControlAppearance unfocusedAppearance,
                              TerminalConnection::ITerminalConnection connection) :
+        TermControl(winrt::guid{}, settings, unfocusedAppearance, connection) {}
+
+    TermControl::TermControl(winrt::guid contentGuid,
+                             IControlSettings settings,
+                             Control::IControlAppearance unfocusedAppearance,
+                             TerminalConnection::ITerminalConnection connection) :
+        _initializedTerminal{ false },
+        _closing{ false },
         _isInternalScrollBarUpdate{ false },
         _autoScrollVelocity{ 0 },
         _autoScrollingPointerPoint{ std::nullopt },
@@ -61,7 +74,22 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     {
         InitializeComponent();
 
-        _interactivity = winrt::make<implementation::ControlInteractivity>(settings, unfocusedAppearance, connection);
+        if (contentGuid != winrt::guid{})
+        {
+            _contentProc = create_instance<Control::ContentProcess>(contentGuid, CLSCTX_LOCAL_SERVER);
+            if (_contentProc != nullptr)
+            {
+                _interactivity = _contentProc.GetInteractivity();
+                _contentWaitInterrupt.create();
+                _createContentWaitThread();
+            }
+        }
+
+        if (_interactivity == nullptr)
+        {
+            _interactivity = winrt::make<implementation::ControlInteractivity>(settings, unfocusedAppearance, connection);
+        }
+
         _core = _interactivity.Core();
 
         // These events might all be triggered by the connection, but that
@@ -74,6 +102,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         // This event is specifically triggered by the renderer thread, a BG thread. Use a weak ref here.
         _core.RendererEnteredErrorState({ get_weak(), &TermControl::_RendererEnteredErrorState });
 
+        _core.ConnectionStateChanged({ get_weak(), &TermControl::_coreConnectionStateChanged });
+
         // These callbacks can only really be triggered by UI interactions. So
         // they don't need weak refs - they can't be triggered unless we're
         // alive.
@@ -682,6 +712,11 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
     TermControl::~TermControl()
     {
+        if (_contentIsOutOfProc())
+        {
+            _contentWaitInterrupt.SetEvent();
+            _contentWaitThread.join();
+        }
         Close();
     }
 
@@ -728,7 +763,12 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
     TerminalConnection::ConnectionState TermControl::ConnectionState() const
     {
-        return _core.ConnectionState();
+        try
+        {
+            return _core.ConnectionState();
+        }
+        CATCH_LOG();
+        return TerminalConnection::ConnectionState::Failed;
     }
 
     winrt::fire_and_forget TermControl::RenderEngineSwapChainChanged(IInspectable /*sender*/, IInspectable /*args*/)
@@ -742,8 +782,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
         if (auto control{ weakThis.get() })
         {
-            const auto chainHandle = reinterpret_cast<HANDLE>(control->_core.SwapChainHandle());
-            _AttachDxgiSwapChainToXaml(chainHandle);
+            control->_acquireAndAttachSwapChainHandle();
         }
     }
 
@@ -795,6 +834,28 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         nativePanel->SetSwapChainHandle(swapChainHandle);
     }
 
+    void TermControl::_acquireAndAttachSwapChainHandle()
+    {
+        const auto chainHandle = reinterpret_cast<HANDLE>(_contentIsOutOfProc() ?
+                                                              _contentProc.RequestSwapChainHandle(GetCurrentProcessId()) :
+                                                              _core.SwapChainHandle());
+        // If we're in-proc, then the render engine has it's own ownership
+        // handle to the swapchain. We don't need to also own it in the XAML
+        // layer. It doesn't really make sense for us to duplicate it to
+        // ourself again, so we're just gonna not.
+        //
+        // If we're out of proc though, the content proc has one handle in
+        // it's process, and now there's a HANDLE in our process with this
+        // value. Wrap that boy up in a unique_handle so that we can release
+        // our handle when needed.
+        if (_contentIsOutOfProc())
+        {
+            _contentSwapChain.reset(chainHandle);
+        }
+
+        _AttachDxgiSwapChainToXaml(chainHandle);
+    }
+
     bool TermControl::_InitializeTerminal()
     {
         if (_initializedTerminal)
@@ -824,13 +885,15 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         const auto coreInitialized = _core.Initialize(panelWidth,
                                                       panelHeight,
                                                       panelScaleX);
-        if (!coreInitialized)
+        // ControlCore::Initialize will return false if it was already
+        // initialized. In that case, don't init the rest of the interactivity,
+        // but do go on and hook us up to the core's swapchain and callbacks.
+        if (coreInitialized)
         {
-            return false;
+            _interactivity.Initialize();
         }
-        _interactivity.Initialize();
 
-        _AttachDxgiSwapChainToXaml(reinterpret_cast<HANDLE>(_core.SwapChainHandle()));
+        _acquireAndAttachSwapChainHandle();
 
         // Tell the DX Engine to notify us when the swap chain changes. We do
         // this after we initially set the swapchain so as to avoid unnecessary
@@ -1836,6 +1899,10 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     {
         if (!_IsClosing())
         {
+            // TODO:GH#5000 - move all the blinking inside of ControlCore.
+            // There's no reason that the timer should live in TermControl just
+            // to hop across the process boundary to toggle the content process.
+            // That can all live in the control core.
             _core.BlinkCursor();
         }
     }
@@ -1850,6 +1917,10 @@ namespace winrt::Microsoft::Terminal::Control::implementation
     {
         if (!_IsClosing())
         {
+            // TODO:GH#5000 - move all the blinking inside of ControlCore.
+            // There's no reason that the timer should live in TermControl just
+            // to hop across the process boundary to toggle the content process.
+            // That can all live in the control core.
             _core.BlinkAttributeTick();
         }
     }
@@ -1997,8 +2068,10 @@ namespace winrt::Microsoft::Terminal::Control::implementation
             // Disconnect the TSF input control so it doesn't receive EditContext events.
             TSFInputControl().Close();
             _autoScrollTimer.Stop();
-
-            _core.Close();
+            if (!_contentIsOutOfProc())
+            {
+                _core.Close();
+            }
         }
     }
 
@@ -3101,6 +3174,11 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         return _core.OwningHwnd();
     }
 
+    void TermControl::_coreConnectionStateChanged(const IInspectable& /*sender*/, const IInspectable& /*args*/)
+    {
+        _ConnectionStateChangedHandlers(*this, nullptr);
+    }
+
     void TermControl::AddMark(const Control::ScrollMark& mark)
     {
         _core.AddMark(mark);

src/cascadia/TerminalControl/TermControl.h

@@ -29,6 +29,11 @@ namespace winrt::Microsoft::Terminal::Control::implementation
                     Control::IControlAppearance unfocusedAppearance,
                     TerminalConnection::ITerminalConnection connection);
 
+        TermControl(winrt::guid contentGuid,
+                    IControlSettings settings,
+                    Control::IControlAppearance unfocusedAppearance,
+                    TerminalConnection::ITerminalConnection connection);
+
         winrt::fire_and_forget UpdateControlSettings(Control::IControlSettings settings);
         winrt::fire_and_forget UpdateControlSettings(Control::IControlSettings settings, Control::IControlAppearance unfocusedAppearance);
         IControlSettings Settings() const;
@@ -96,6 +101,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         winrt::fire_and_forget _RendererEnteredErrorState(IInspectable sender, IInspectable args);
 
         void _RenderRetryButton_Click(const IInspectable& button, const IInspectable& args);
+        void _ContentDiedCloseButton_Click(const IInspectable& button, const IInspectable& args);
         winrt::fire_and_forget _RendererWarning(IInspectable sender,
                                                 Control::RendererWarningArgs args);
 
@@ -143,9 +149,10 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         PROJECTED_FORWARDED_TYPED_EVENT(TitleChanged,           IInspectable, Control::TitleChangedEventArgs, _core, TitleChanged);
         PROJECTED_FORWARDED_TYPED_EVENT(TabColorChanged,        IInspectable, IInspectable, _core, TabColorChanged);
         PROJECTED_FORWARDED_TYPED_EVENT(SetTaskbarProgress,     IInspectable, IInspectable, _core, TaskbarProgressChanged);
-        PROJECTED_FORWARDED_TYPED_EVENT(ConnectionStateChanged, IInspectable, IInspectable, _core, ConnectionStateChanged);
         PROJECTED_FORWARDED_TYPED_EVENT(ShowWindowChanged,      IInspectable, Control::ShowWindowArgs, _core, ShowWindowChanged);
 
+        TYPED_EVENT(ConnectionStateChanged, IInspectable, IInspectable);
+
         PROJECTED_FORWARDED_TYPED_EVENT(PasteFromClipboard, IInspectable, Control::PasteFromClipboardEventArgs, _interactivity, PasteFromClipboard);
 
         TYPED_EVENT(OpenHyperlink,             IInspectable, Control::OpenHyperlinkEventArgs);
@@ -174,6 +181,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         Control::TermControlAutomationPeer _automationPeer{ nullptr };
         Control::ControlInteractivity _interactivity{ nullptr };
         Control::ControlCore _core{ nullptr };
+        Control::ContentProcess _contentProc{ nullptr };
 
         winrt::com_ptr<SearchBoxControl> _searchBox;
 
@@ -213,6 +221,14 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         winrt::Windows::UI::Xaml::Controls::SwapChainPanel::LayoutUpdated_revoker _layoutUpdatedRevoker;
         bool _showMarksInScrollbar{ false };
 
+        wil::unique_event _contentWaitInterrupt;
+        std::thread _contentWaitThread;
+        wil::unique_handle _contentSwapChain;
+        void _createContentWaitThread();
+        bool _contentIsOutOfProc() const;
+
+        void _acquireAndAttachSwapChainHandle();
+
         bool _isBackgroundLight{ false };
 
         inline bool _IsClosing() const noexcept
@@ -307,8 +323,12 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         winrt::fire_and_forget _coreTransparencyChanged(IInspectable sender, Control::TransparencyChangedEventArgs args);
         void _coreRaisedNotice(const IInspectable& s, const Control::NoticeEventArgs& args);
         void _coreWarningBell(const IInspectable& sender, const IInspectable& args);
+
         void _coreFoundMatch(const IInspectable& sender, const Control::FoundResultsArgs& args);
 
+        winrt::fire_and_forget _raiseContentDied();
+        void _coreConnectionStateChanged(const IInspectable& sender, const IInspectable& args);
+
         til::point _toPosInDips(const Core::Point terminalCellPos);
         void _throttledUpdateScrollbar(const ScrollBarUpdate& update);
     };

src/cascadia/TerminalControl/TermControl.idl

@@ -17,6 +17,11 @@ namespace Microsoft.Terminal.Control
                                                    ICoreState,
                                                    Windows.UI.Xaml.Data.INotifyPropertyChanged
     {
+        TermControl(Guid contentGuid,
+                    IControlSettings settings,
+                    IControlAppearance unfocusedAppearance,
+                    Microsoft.Terminal.TerminalConnection.ITerminalConnection connection);
+
         TermControl(IControlSettings settings,
                     IControlAppearance unfocusedAppearance,
                     Microsoft.Terminal.TerminalConnection.ITerminalConnection connection);

src/cascadia/TerminalControl/TermControl.xaml

@@ -1305,6 +1305,27 @@
             </Border>
         </Grid>
 
+        <Grid x:Name="ContentDiedNotice"
+              HorizontalAlignment="Center"
+              VerticalAlignment="Center"
+              x:Load="False">
+            <Border Margin="8,8,8,8"
+                    Padding="8,8,8,8"
+                    Background="{ThemeResource SystemControlBackgroundAltHighBrush}"
+                    BorderBrush="{ThemeResource SystemAccentColor}"
+                    BorderThickness="2,2,2,2"
+                    CornerRadius="{ThemeResource OverlayCornerRadius}">
+                <StackPanel>
+                    <TextBlock x:Uid="TermControl_ContentDiedTextBlock"
+                               HorizontalAlignment="Center"
+                               TextWrapping="WrapWholeWords" />
+                    <Button x:Uid="TermControl_ContentDiedButton"
+                            HorizontalAlignment="Right"
+                            Click="_ContentDiedCloseButton_Click" />
+                </StackPanel>
+            </Border>
+        </Grid>
+
     </Grid>
 
 </UserControl>

src/cascadia/TerminalControl/TermControlAutomationPeer.cpp

@@ -4,6 +4,8 @@
 #include "pch.h"
 #include <UIAutomationCore.h>
 #include <LibraryResources.h>
+#include <ScopedResourceLoader.h>
+
 #include "TermControlAutomationPeer.h"
 #include "TermControl.h"
 #include "TermControlAutomationPeer.g.cpp"
@@ -83,7 +85,7 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         _contentAutomationPeer.TextChanged([this](auto&&, auto&&) { SignalTextChanged(); });
         _contentAutomationPeer.CursorChanged([this](auto&&, auto&&) { SignalCursorChanged(); });
         _contentAutomationPeer.NewOutput([this](auto&&, hstring newOutput) { NotifyNewOutput(newOutput); });
-        _contentAutomationPeer.ParentProvider(*this);
+        _contentAutomationPeer.ParentProvider(GetParentProvider());
     };
 
     // Method Description:
@@ -117,6 +119,12 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         }
     }
 
+    XamlAutomation::IRawElementProviderSimple TermControlAutomationPeer::GetParentProvider()
+    {
+        const auto parentProvider = this->ProviderFromPeer(*this);
+        return parentProvider;
+    }
+
     // Method Description:
     // - Signals the ui automation client that the terminal's selection has changed and should be updated
     // Arguments:
@@ -261,7 +269,19 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
     hstring TermControlAutomationPeer::GetLocalizedControlTypeCore() const
     {
-        return RS_(L"TerminalControl_ControlType");
+        // TerminalControl_ControlType is "terminal" in english. Usually, this
+        // will return the localized version of that string. For applications
+        // that use the TermControl that don't package up all the resources in a
+        // way that they can be accessed, this will fall back to just "terminal"
+        // (notably, the scratch solution doesn't package these resources)
+        //
+        // Stash this in a static variable in the off chance that this is called
+        // in a hot path by some a11y tool. There's absolutely no chance it's
+        // gonna change, so this is safe enough.
+        static auto resMap{ ScopedResourceLoader(L"Microsoft.Terminal.Control/Resources").GetResourceMap() };
+        return resMap ?
+                   RS_(L"TerminalControl_ControlType") :
+                   L"terminal";
     }
 
     Windows::Foundation::IInspectable TermControlAutomationPeer::GetPatternCore(PatternInterface patternInterface) const

src/cascadia/TerminalControl/TermControlAutomationPeer.h

@@ -48,8 +48,11 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
         void UpdateControlBounds();
         void SetControlPadding(const Core::Padding padding);
+
         void RecordKeyEvent(const WORD vkey);
 
+        Windows::UI::Xaml::Automation::Provider::IRawElementProviderSimple GetParentProvider();
+
 #pragma region FrameworkElementAutomationPeer
         hstring GetClassNameCore() const;
         Windows::UI::Xaml::Automation::Peers::AutomationControlType GetAutomationControlTypeCore() const;

src/cascadia/TerminalControl/TermControlAutomationPeer.idl

@@ -12,5 +12,6 @@ namespace Microsoft.Terminal.Control
 
         void UpdateControlBounds();
         void SetControlPadding(Microsoft.Terminal.Core.Padding padding);
+        Windows.UI.Xaml.Automation.Provider.IRawElementProviderSimple GetParentProvider();
     }
 }

src/cascadia/TerminalControl/TermControlContentManagement.cpp

@@ -0,0 +1,155 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+//
+// The functions in this class are specific to the handling of out-of-proc
+// content processes by the TermControl. Putting them all in one file keeps
+// TermControl.cpp a little less cluttered.
+
+#include "pch.h"
+#include "TermControl.h"
+
+using namespace ::Microsoft::Console::Types;
+using namespace winrt::Windows::UI::Xaml;
+using namespace winrt::Windows::UI::Core;
+using namespace winrt::Windows::System;
+
+namespace winrt::Microsoft::Terminal::Control::implementation
+{
+    bool TermControl::_contentIsOutOfProc() const
+    {
+        return _contentProc != nullptr;
+    }
+
+    bool s_waitOnContentProcess(uint64_t contentPid, HANDLE contentWaitInterrupt)
+    {
+        // This is the array of HANDLEs that we're going to wait on in
+        // WaitForMultipleObjects below.
+        // * waits[0] will be the handle to the content process. It gets
+        //   signalled when the process exits / dies.
+        // * waits[1] is the handle to our _contentWaitInterrupt event. Another
+        //   thread can use that to manually break this loop. We'll do that when
+        //   we're getting torn down.
+        HANDLE waits[2];
+        waits[1] = contentWaitInterrupt;
+        bool displayError = true;
+
+        // At any point in all this, the content process might die. If it does,
+        // we want to raise an error message, to inform that this control is now
+        // dead.
+        try
+        {
+            // This might fail to even ask the content for it's PID.
+            wil::unique_handle hContent{ OpenProcess(SYNCHRONIZE,
+                                                     FALSE,
+                                                     static_cast<DWORD>(contentPid)) };
+
+            // If we fail to open the content, then they don't exist
+            //  anymore! We'll need to immediately raise the notification that the content has died.
+            if (hContent.get() == nullptr)
+            {
+                const auto gle = GetLastError();
+                TraceLoggingWrite(g_hTerminalControlProvider,
+                                  "TermControl_FailedToOpenContent",
+                                  TraceLoggingUInt64(gle, "lastError", "The result of GetLastError"),
+                                  TraceLoggingLevel(WINEVENT_LEVEL_VERBOSE),
+                                  TraceLoggingKeyword(TIL_KEYWORD_TRACE));
+                return displayError;
+            }
+
+            waits[0] = hContent.get();
+
+            switch (WaitForMultipleObjects(2, waits, FALSE, INFINITE))
+            {
+            case WAIT_OBJECT_0 + 0: // waits[0] was signaled, the handle to the content process
+
+                TraceLoggingWrite(g_hTerminalControlProvider,
+                                  "TermControl_ContentDied",
+                                  TraceLoggingLevel(WINEVENT_LEVEL_VERBOSE),
+                                  TraceLoggingKeyword(TIL_KEYWORD_TRACE));
+                break;
+
+            case WAIT_OBJECT_0 + 1: // waits[1] was signaled, our manual interrupt
+
+                TraceLoggingWrite(g_hTerminalControlProvider,
+                                  "TermControl_ContentWaitInterrupted",
+                                  TraceLoggingLevel(WINEVENT_LEVEL_VERBOSE),
+                                  TraceLoggingKeyword(TIL_KEYWORD_TRACE));
+                displayError = false;
+                break;
+
+            case WAIT_TIMEOUT:
+                // This should be impossible.
+                TraceLoggingWrite(g_hTerminalControlProvider,
+                                  "TermControl_ContentWaitTimeout",
+                                  TraceLoggingLevel(WINEVENT_LEVEL_VERBOSE),
+                                  TraceLoggingKeyword(TIL_KEYWORD_TRACE));
+                break;
+
+            default:
+            {
+                // Returning any other value is invalid. Just die.
+                const auto gle = GetLastError();
+                TraceLoggingWrite(g_hTerminalControlProvider,
+                                  "TermControl_WaitFailed",
+                                  TraceLoggingUInt64(gle, "lastError", "The result of GetLastError"),
+                                  TraceLoggingLevel(WINEVENT_LEVEL_VERBOSE),
+                                  TraceLoggingKeyword(TIL_KEYWORD_TRACE));
+                break;
+            }
+            }
+        }
+        catch (...)
+        {
+            // Theoretically, if window[1] dies when we're trying to get
+            // its PID we'll get here. We can probably just exit here.
+
+            TraceLoggingWrite(g_hTerminalControlProvider,
+                              "TermControl_ExceptionInWaitThread",
+                              TraceLoggingLevel(WINEVENT_LEVEL_VERBOSE),
+                              TraceLoggingKeyword(TIL_KEYWORD_TRACE));
+        }
+        return displayError;
+    }
+
+    void TermControl::_createContentWaitThread()
+    {
+        _contentWaitThread = std::thread([weakThis = get_weak(), contentPid = _contentProc.GetPID(), contentWaitInterrupt = _contentWaitInterrupt.get()] {
+            if (s_waitOnContentProcess(contentPid, contentWaitInterrupt))
+            {
+                // When s_waitOnContentProcess returns, if it returned true, we
+                // should display a dialog in our bounds to indicate that we
+                // were closed unexpectedly. If we closed in an expected way,
+                // then s_waitOnContentProcess will return false.
+                if (auto control{ weakThis.get() })
+                {
+                    control->_raiseContentDied();
+                }
+            }
+        });
+    }
+
+    winrt::fire_and_forget TermControl::_raiseContentDied()
+    {
+        auto weakThis{ get_weak() };
+        co_await winrt::resume_foreground(Dispatcher());
+
+        if (auto control{ weakThis.get() }; !control->_IsClosing())
+        {
+            if (auto loadedUiElement{ FindName(L"ContentDiedNotice") })
+            {
+                if (auto uiElement{ loadedUiElement.try_as<::winrt::Windows::UI::Xaml::UIElement>() })
+                {
+                    uiElement.Visibility(Visibility::Visible);
+                }
+            }
+        }
+    }
+    // Method Description:
+    // - Handler for when the "Content Died" dialog's button is clicked.
+    void TermControl::_ContentDiedCloseButton_Click(IInspectable const& /*sender*/, IInspectable const& /*args*/)
+    {
+        // Alert whoever's hosting us that the connection was closed.
+        // When they come asking what the new connection state is, we'll reply with Closed
+        _ConnectionStateChangedHandlers(*this, nullptr);
+    }
+}

src/cascadia/TerminalControl/TerminalControlLib.vcxproj

@@ -34,6 +34,9 @@
   <!-- ========================= Headers ======================== -->
   <ItemGroup>
     <ClInclude Include="pch.h" />
+    <ClInclude Include="ContentProcess.h">
+      <DependentUpon>ContentProcess.idl</DependentUpon>
+    </ClInclude>
     <ClInclude Include="ControlCore.h">
       <DependentUpon>ControlCore.idl</DependentUpon>
     </ClInclude>
@@ -64,13 +67,18 @@
     <ClInclude Include="TSFInputControl.h">
       <DependentUpon>TSFInputControl.xaml</DependentUpon>
     </ClInclude>
-    <ClInclude Include="XamlUiaTextRange.h" />
+    <ClInclude Include="XamlUiaTextRange.h" >
+      <DependentUpon>XamlUiaTextRange.idl</DependentUpon>
+    </ClInclude>
   </ItemGroup>
   <!-- ========================= Cpp Files ======================== -->
   <ItemGroup>
     <ClCompile Include="pch.cpp">
       <PrecompiledHeader>Create</PrecompiledHeader>
     </ClCompile>
+    <ClCompile Include="ContentProcess.cpp">
+      <DependentUpon>ContentProcess.idl</DependentUpon>
+    </ClCompile>
     <ClCompile Include="ControlCore.cpp">
       <DependentUpon>ControlCore.idl</DependentUpon>
     </ClCompile>
@@ -93,6 +101,9 @@
     <ClCompile Include="TermControl.cpp">
       <DependentUpon>TermControl.xaml</DependentUpon>
     </ClCompile>
+    <ClCompile Include="TermControlContentManagement.cpp">
+      <DependentUpon>TermControl.xaml</DependentUpon>
+    </ClCompile>
     <ClCompile Include="TSFInputControl.cpp">
       <DependentUpon>TSFInputControl.xaml</DependentUpon>
     </ClCompile>
@@ -103,10 +114,13 @@
     <ClCompile Include="InteractivityAutomationPeer.cpp">
       <DependentUpon>InteractivityAutomationPeer.idl</DependentUpon>
     </ClCompile>
-    <ClCompile Include="XamlUiaTextRange.cpp" />
+    <ClCompile Include="XamlUiaTextRange.cpp" >
+      <DependentUpon>XamlUiaTextRange.idl</DependentUpon>
+    </ClCompile>
   </ItemGroup>
   <!-- ========================= idl Files ======================== -->
   <ItemGroup>
+    <Midl Include="ContentProcess.idl" />
     <Midl Include="ControlCore.idl" />
     <Midl Include="ControlInteractivity.idl" />
     <Midl Include="ICoreState.idl" />
@@ -129,6 +143,7 @@
     <Midl Include="TSFInputControl.idl">
       <DependentUpon>TSFInputControl.xaml</DependentUpon>
     </Midl>
+    <Midl Include="XamlUiaTextRange.idl" />
   </ItemGroup>
   <!-- ========================= XAML Files ======================== -->
   <ItemGroup>

src/cascadia/TerminalControl/XamlUiaTextRange.h

@@ -21,13 +21,13 @@ Author(s):
 #pragma once
 
 #include "TermControlAutomationPeer.h"
+#include "XamlUiaTextRange.g.h"
 #include <UIAutomationCore.h>
 #include "../types/TermControlUiaTextRange.hpp"
 
 namespace winrt::Microsoft::Terminal::Control::implementation
 {
-    class XamlUiaTextRange :
-        public winrt::implements<XamlUiaTextRange, Windows::UI::Xaml::Automation::Provider::ITextRangeProvider>
+    class XamlUiaTextRange : public XamlUiaTextRangeT<XamlUiaTextRange>
     {
     public:
         XamlUiaTextRange(::ITextRangeProvider* uiaProvider, Windows::UI::Xaml::Automation::Provider::IRawElementProviderSimple parentProvider) :

src/cascadia/TerminalControl/XamlUiaTextRange.idl

@@ -0,0 +1,10 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
+namespace Microsoft.Terminal.Control
+{
+    [default_interface] runtimeclass XamlUiaTextRange :
+        Windows.UI.Xaml.Automation.Provider.ITextRangeProvider
+    {
+    }
+}

src/cascadia/TerminalControl/pch.h

@@ -47,6 +47,7 @@
 #include <winrt/Windows.ui.xaml.markup.h>
 #include <winrt/Windows.ui.xaml.shapes.h>
 #include <winrt/Windows.ApplicationModel.DataTransfer.h>
+#include <winrt/Windows.ApplicationModel.Resources.Core.h>
 #include <winrt/Windows.Storage.h>
 #include <winrt/Windows.UI.Xaml.Shapes.h>
 

src/cascadia/WindowsTerminal/ContentProcessMain.cpp

@@ -0,0 +1,153 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
+#include "pch.h"
+#include "AppHost.h"
+#include "resource.h"
+#include "../types/inc/User32Utils.hpp"
+#include <WilErrorReporting.h>
+
+using namespace winrt;
+using namespace winrt::Windows::UI;
+using namespace winrt::Windows::UI::Composition;
+using namespace winrt::Windows::UI::Xaml::Hosting;
+using namespace winrt::Windows::Foundation::Numerics;
+
+// We keep a weak ref to our ContentProcess singleton here.
+// Why?
+//
+// We need to always return the _same_ ContentProcess when someone comes to
+// instantiate this class. So we want to track the single instance we make. We
+// also want to track when the last outstanding reference to this object is
+// removed. If we're keeping a strong ref, then the ref count will always be > 1
+
+static winrt::weak_ref<winrt::Microsoft::Terminal::Control::ContentProcess> g_weak{ nullptr };
+static wil::unique_event g_canExitThread;
+
+struct ContentProcessFactory : implements<ContentProcessFactory, IClassFactory>
+{
+    ContentProcessFactory(winrt::guid g) :
+        _guid{ g } {};
+
+    HRESULT __stdcall CreateInstance(IUnknown* outer, GUID const& iid, void** result) noexcept final
+    {
+        *result = nullptr;
+        if (outer)
+        {
+            return CLASS_E_NOAGGREGATION;
+        }
+
+        if (!g_weak)
+        {
+            // Instantiate the ContentProcess here
+            winrt::Microsoft::Terminal::Control::ContentProcess strong{};
+
+            // Now, create a weak ref to that ContentProcess object.
+            winrt::weak_ref<winrt::Microsoft::Terminal::Control::ContentProcess> weak{ strong };
+
+            // Stash away that weak ref for future callers.
+            g_weak = weak;
+            return strong.as(iid, result);
+        }
+        else
+        {
+            auto strong = g_weak.get();
+            // !! LOAD BEARING !! If you set this event in the _first_ branch
+            // here, when we first create the object, then there will be _no_
+            // references to the ContentProcess object for a small slice. We'll
+            // stash the ContentProcess in the weak_ptr, and return it, and at
+            // that moment, there will be 0 outstanding references, it'll dtor,
+            // and we'll ExitProcess.
+            //
+            // Instead, set the event here, once there's already a reference
+            // outside of just the weak one we keep. Experimentation showed this
+            // was always hit when creating the ContentProcess at least once.
+            g_canExitThread.SetEvent();
+            return strong.as(iid, result);
+        }
+    }
+
+    HRESULT __stdcall LockServer(BOOL) noexcept final
+    {
+        return S_OK;
+    }
+
+private:
+    winrt::guid _guid;
+};
+
+static winrt::com_ptr<ContentProcessFactory> g_contentProcFactory{ nullptr };
+
+static bool checkIfContentProcess(winrt::guid& contentProcessGuid, HANDLE& eventHandle)
+{
+    std::vector<std::wstring> args;
+
+    if (auto commandline{ GetCommandLineW() })
+    {
+        int argc = 0;
+
+        // Get the argv, and turn them into a hstring array to pass to the app.
+        wil::unique_any<LPWSTR*, decltype(&::LocalFree), ::LocalFree> argv{ CommandLineToArgvW(commandline, &argc) };
+        if (argv)
+        {
+            for (auto& elem : wil::make_range(argv.get(), argc))
+            {
+                args.emplace_back(elem);
+            }
+        }
+    }
+    if (args.size() == 5 &&
+        args.at(1) == L"--content" &&
+        args.at(3) == L"--signal")
+    {
+        auto& guidString{ args.at(2) };
+        auto canConvert = guidString.length() == 38 && guidString.front() == '{' && guidString.back() == '}';
+        if (canConvert)
+        {
+            GUID result{};
+            THROW_IF_FAILED(IIDFromString(guidString.c_str(), &result));
+            contentProcessGuid = result;
+
+            eventHandle = reinterpret_cast<HANDLE>(wcstoul(args.at(4).c_str(),
+                                                           nullptr /*endptr*/,
+                                                           16 /*base*/));
+            return true;
+        }
+    }
+    return false;
+}
+
+static void doContentProcessThing(const winrt::guid& contentProcessGuid, const HANDLE& eventHandle)
+{
+    // !! LOAD BEARING !! - important to be a MTA for these COM calls.
+    winrt::init_apartment();
+    DWORD registrationHostClass{};
+    g_contentProcFactory = make_self<ContentProcessFactory>(contentProcessGuid);
+    check_hresult(CoRegisterClassObject(contentProcessGuid,
+                                        g_contentProcFactory.get(),
+                                        CLSCTX_LOCAL_SERVER,
+                                        REGCLS_MULTIPLEUSE,
+                                        &registrationHostClass));
+
+    // Signal the event handle that was passed to us that we're now set up and
+    // ready to go.
+    SetEvent(eventHandle);
+    CloseHandle(eventHandle);
+}
+
+void TryRunAsContentProcess()
+{
+    winrt::guid contentProcessGuid{};
+    HANDLE eventHandle{ INVALID_HANDLE_VALUE };
+    if (checkIfContentProcess(contentProcessGuid, eventHandle))
+    {
+        g_canExitThread = wil::unique_event{ CreateEvent(nullptr, true, false, L"ContentProcessReady") };
+
+        doContentProcessThing(contentProcessGuid, eventHandle);
+
+        WaitForSingleObject(g_canExitThread.get(), INFINITE);
+        // This is the conhost thing - if we ExitThread the main thread, the
+        // other threads can keep running till one calls ExitProcess.
+        ExitThread(0);
+    }
+}

src/cascadia/WindowsTerminal/WindowsTerminal.vcxproj

@@ -63,6 +63,7 @@
       <PrecompiledHeader>Create</PrecompiledHeader>
     </ClCompile>
     <ClCompile Include="main.cpp" />
+    <ClCompile Include="ContentProcessMain.cpp" />
     <ClCompile Include="AppHost.cpp" />
     <ClCompile Include="IslandWindow.cpp" />
     <ClCompile Include="NonClientIslandWindow.cpp" />

src/cascadia/WindowsTerminal/main.cpp

@@ -31,6 +31,8 @@ TRACELOGGING_DEFINE_PROVIDER(
 #include <LibraryResources.h>
 UTILS_DEFINE_LIBRARY_RESOURCE_SCOPE(L"TerminalApp/Resources");
 
+void TryRunAsContentProcess();
+
 // Routine Description:
 // - Takes an image architecture and locates a string resource that maps to that architecture.
 // Arguments:
@@ -119,6 +121,21 @@ int __stdcall wWinMain(HINSTANCE, HINSTANCE, LPWSTR, int)
     // should choose and install the correct one from the bundle.
     EnsureNativeArchitecture();
 
+    // Content processes are only enabled in dev builds, so that we can check
+    // the feature in to dev builds one piece at a time.
+    if constexpr (Feature_ContentProcess::IsEnabled())
+    {
+        // If we _are_ a content process, then this function will call ExitThread(),
+        // after spawning some COM threads to deal with inbound COM requests to the
+        // ContentProcess object.
+        TryRunAsContentProcess();
+        // If we are a content process, then TryRunAsContentProcess will
+        // ExitThread before it returns, so that nothing else will run here.
+    }
+
+    // If we weren't a content process, then we'll just move on, and do the
+    // normal WindowsTerminal thing.
+
     // Make sure to call this so we get WM_POINTER messages.
     EnableMouseInPointer(true);
 

src/features.xml

@@ -124,6 +124,28 @@
         </alwaysDisabledBrandingTokens>
     </feature>
 
+    <feature>
+        <name>Feature_ContentProcess</name>
+        <description>Enables the --content flag, for allowing TermControls to be created as OOP content for the window.</description>
+        <stage>AlwaysDisabled</stage>
+        <!-- This is VERY MUCH a WIP, so we're using velocity to start checking in code to dev branches without shipping it. -->
+        <alwaysEnabledBrandingTokens>
+            <brandingToken>Dev</brandingToken>
+        </alwaysEnabledBrandingTokens>
+    </feature>
+
+    <feature>
+        <name>Feature_DECPSViaMidiPlayer</name>
+        <description>Enables playing sound via DECPS using the MIDI player.</description>
+        <stage>AlwaysDisabled</stage>
+        <!-- We're disabling this for WindowsInbox and Stable because it requires an additional
+             package dependency or library dependency. -->
+        <alwaysEnabledBrandingTokens>
+            <brandingToken>Dev</brandingToken>
+            <brandingToken>Preview</brandingToken>
+        </alwaysEnabledBrandingTokens>
+    </feature>
+
     <feature>
         <name>Feature_ScrollbarMarks</name>
         <description>Enables the experimental scrollbar marks feature.</description>