René's URL Explorer Experiment


Title: Better narrowing for enums and other types with known equality by hauntsaninja · Pull Request #21281 · python/mypy · GitHub

Open Graph Title: Better narrowing for enums and other types with known equality by hauntsaninja · Pull Request #21281 · python/mypy

X Title: Better narrowing for enums and other types with known equality by hauntsaninja · Pull Request #21281 · python/mypy

Description: Optional static typing for Python. Contribute to python/mypy development by creating an account on GitHub.

Open Graph Description: Fixes #21187, fully fixes this comment #9003 (comment) (previously improved on in 1.20 narrowing changes) This diff adds general functionality that replaces a few different pieces of ad hoc logic: ...

X Description: Fixes #21187, fully fixes this comment #9003 (comment) (previously improved on in 1.20 narrowing changes) This diff adds general functionality that replaces a few different pieces of ad hoc logic: ...

Opengraph URL: https://github.com/python/mypy/pull/21281

X: @github

direct link

Domain: github.com

route-pattern/_view_fragments/voltron/pull_requests/show/:user_id/:repository/:id/pull_request_layout(.:format)
route-controllervoltron_pull_requests_fragments
route-actionpull_request_layout
fetch-noncev2:3de50fe7-6852-424b-f48a-25e52779b8a5
current-catalog-service-hashae870bc5e265a340912cde392f23dad3671a0a881730ffdadd82f2f57d81641b
request-idE98E:119971:447879:5BD952:6A57FF75
html-safe-nonced7ba5375dfd65dfdf569b60ac8db9a2a34205f0d22275f0b4536f1e4d89787bf
visitor-payloadeyJyZWZlcnJlciI6IiIsInJlcXVlc3RfaWQiOiJFOThFOjExOTk3MTo0NDc4Nzk6NUJEOTUyOjZBNTdGRjc1IiwidmlzaXRvcl9pZCI6IjUyNjQ2Njg0MDUyMzY0OTgyOTMiLCJyZWdpb25fZWRnZSI6ImlhZCIsInJlZ2lvbl9yZW5kZXIiOiJpYWQifQ==
visitor-hmaccf1419d6ef2fa0dbc22b8f299b465d963060a8a0127abbe89b66c098be2c533a
hovercard-subject-tagpull_request:3560358538
github-keyboard-shortcutsrepository,pull-request-list,pull-request-conversation,pull-request-files-changed,copilot
google-site-verificationApib7-x98H0j5cPqHWwSMm6dNU4GmODRoqxLiDzdx9I
octolytics-urlhttps://collector.github.com/github/collect
analytics-location///voltron/pull_requests_fragments/pull_request_layout
fb:app_id1401488693436528
apple-itunes-appapp-id=1477376905, app-argument=https://github.com/_view_fragments/voltron/pull_requests/show/python/mypy/21281/pull_request_layout
twitter:imagehttps://opengraph.githubassets.com/b79f64dca97b868e63ac7eac73c75b7a442e9054f8eb6a5495909d4c74e39ad4/python/mypy/pull/21281
twitter:cardsummary_large_image
og:imagehttps://opengraph.githubassets.com/b79f64dca97b868e63ac7eac73c75b7a442e9054f8eb6a5495909d4c74e39ad4/python/mypy/pull/21281
og:image:altFixes #21187, fully fixes this comment #9003 (comment) (previously improved on in 1.20 narrowing changes) This diff adds general functionality that replaces a few different pieces of ad hoc logic: ...
og:image:width1200
og:image:height600
og:site_nameGitHub
og:typeobject
og:author:usernamehauntsaninja
hostnamegithub.com
expected-hostnamegithub.com
None49c8c15fabcbf356d607a90ca115c13b273e42ff8b74155de050fd229a9b0121
turbo-cache-controlno-cache
go-importgithub.com/python/mypy git https://github.com/python/mypy.git
octolytics-dimension-user_id1525981
octolytics-dimension-user_loginpython
octolytics-dimension-repository_id7053637
octolytics-dimension-repository_nwopython/mypy
octolytics-dimension-repository_publictrue
octolytics-dimension-repository_is_forkfalse
octolytics-dimension-repository_network_root_id7053637
octolytics-dimension-repository_network_root_nwopython/mypy
turbo-body-classeslogged-out env-production page-responsive
disable-turbofalse
browser-stats-urlhttps://api.github.com/_private/browser/stats
browser-errors-urlhttps://api.github.com/_private/browser/errors
release3fb1f684e7a833eb1b2d01d39875a2b52cb4fe9b
ui-targetfull
theme-color#1e2327
color-schemelight dark

Links:

Skip to contenthttps://github.com/python/mypy/pull/21281#start-of-content
https://github.com/
Sign in https://github.com/login?return_to=https%3A%2F%2Fgithub.com%2Fpython%2Fmypy%2Fpull%2F21281
GitHub CopilotWrite better code with AIhttps://github.com/features/copilot
GitHub Copilot appDirect agents from issue to mergehttps://github.com/features/ai/github-app
MCP RegistryNewIntegrate external toolshttps://github.com/mcp
ActionsAutomate any workflowhttps://github.com/features/actions
CodespacesInstant dev environmentshttps://github.com/features/codespaces
IssuesPlan and track workhttps://github.com/features/issues
Code ReviewManage code changeshttps://github.com/features/code-review
GitHub Advanced SecurityFind and fix vulnerabilitieshttps://github.com/security/advanced-security
Code securitySecure your code as you buildhttps://github.com/security/advanced-security/code-security
Secret protectionStop leaks before they starthttps://github.com/security/advanced-security/secret-protection
Why GitHubhttps://github.com/why-github
Documentationhttps://docs.github.com
Bloghttps://github.blog
Changeloghttps://github.blog/changelog
Marketplacehttps://github.com/marketplace
View all featureshttps://github.com/features
Enterpriseshttps://github.com/enterprise
Small and medium teamshttps://github.com/team
Startupshttps://github.com/enterprise/startups
Nonprofitshttps://github.com/solutions/industry/nonprofits
App Modernizationhttps://github.com/solutions/use-case/app-modernization
DevSecOpshttps://github.com/solutions/use-case/devsecops
DevOpshttps://github.com/solutions/use-case/devops
CI/CDhttps://github.com/solutions/use-case/ci-cd
View all use caseshttps://github.com/solutions/use-case
Healthcarehttps://github.com/solutions/industry/healthcare
Financial serviceshttps://github.com/solutions/industry/financial-services
Manufacturinghttps://github.com/solutions/industry/manufacturing
Governmenthttps://github.com/solutions/industry/government
View all industrieshttps://github.com/solutions/industry
View all solutionshttps://github.com/solutions
AIhttps://github.com/resources/articles?topic=ai
Software Developmenthttps://github.com/resources/articles?topic=software-development
DevOpshttps://github.com/resources/articles?topic=devops
Securityhttps://github.com/resources/articles?topic=security
View all topicshttps://github.com/resources/articles
Customer storieshttps://github.com/customer-stories
Events & webinarshttps://github.com/resources/events
Ebooks & reportshttps://github.com/resources/whitepapers
Business insightshttps://github.com/solutions/executive-insights
GitHub Skillshttps://skills.github.com
Documentationhttps://docs.github.com
Customer supporthttps://support.github.com
Community forumhttps://github.com/orgs/community/discussions
Trust centerhttps://github.com/trust-center
Partnershttps://github.com/partners
View all resourceshttps://github.com/resources
GitHub SponsorsFund open source developershttps://github.com/open-source/sponsors
Security Labhttps://securitylab.github.com
Maintainer Communityhttps://maintainers.github.com
Acceleratorhttps://github.com/open-source/accelerator
GitHub Starshttps://stars.github.com
Archive Programhttps://archiveprogram.github.com
Topicshttps://github.com/topics
Trendinghttps://github.com/trending
Collectionshttps://github.com/collections
Enterprise platformAI-powered developer platformhttps://github.com/enterprise
GitHub Advanced SecurityEnterprise-grade security featureshttps://github.com/security/advanced-security
Copilot for BusinessEnterprise-grade AI featureshttps://github.com/features/copilot/copilot-business
Premium SupportEnterprise-grade 24/7 supporthttps://github.com/enterprise/premium-support
Pricinghttps://github.com/pricing
Search syntax tipshttps://docs.github.com/search-github/github-code-search/understanding-github-code-search-syntax
documentationhttps://docs.github.com/search-github/github-code-search/understanding-github-code-search-syntax
Sign in https://github.com/login?return_to=https%3A%2F%2Fgithub.com%2Fpython%2Fmypy%2Fpull%2F21281
Sign up https://github.com/signup?ref_cta=Sign+up&ref_loc=header+logged+out&ref_page=%2F%3Cuser-name%3E%2F%3Crepo-name%3E%2Fvoltron%2Fpull_requests_fragments%2Fpull_request_layout&source=header-repo&source_repo=python%2Fmypy
Reloadhttps://github.com/python/mypy/pull/21281
Reloadhttps://github.com/python/mypy/pull/21281
Reloadhttps://github.com/python/mypy/pull/21281
Please reload this pagehttps://github.com/python/mypy/pull/21281
python https://github.com/python
mypyhttps://github.com/python/mypy
Please reload this pagehttps://github.com/python/mypy/pull/21281
Notifications https://github.com/login?return_to=%2Fpython%2Fmypy
Fork 3.2k https://github.com/login?return_to=%2Fpython%2Fmypy
Star 20.5k https://github.com/login?return_to=%2Fpython%2Fmypy
Code https://github.com/python/mypy
Issues 2.7k https://github.com/python/mypy/issues
Pull requests 465 https://github.com/python/mypy/pulls
Actions https://github.com/python/mypy/actions
Projects https://github.com/python/mypy/projects
Wiki https://github.com/python/mypy/wiki
Security and quality 0 https://github.com/python/mypy/security
Insights https://github.com/python/mypy/pulse
Code https://github.com/python/mypy
Issues https://github.com/python/mypy/issues
Pull requests https://github.com/python/mypy/pulls
Actions https://github.com/python/mypy/actions
Projects https://github.com/python/mypy/projects
Wiki https://github.com/python/mypy/wiki
Security and quality https://github.com/python/mypy/security
Insights https://github.com/python/mypy/pulse
hauntsaninjahttps://github.com/hauntsaninja
python:masterhttps://github.com/python/mypy/tree/master
hauntsaninja:enumident2https://github.com/hauntsaninja/mypy/tree/enumident2
Conversationhttps://github.com/python/mypy/pull/21281
Commits2 (2)https://github.com/python/mypy/pull/21281/commits
Checkshttps://github.com/python/mypy/pull/21281/checks
Files changedhttps://github.com/python/mypy/pull/21281/files
Better narrowing for enums and other types with known equalityhttps://github.com/python/mypy/pull/21281#top
hauntsaninjahttps://github.com/hauntsaninja
python:masterhttps://github.com/python/mypy/tree/master
hauntsaninja:enumident2https://github.com/hauntsaninja/mypy/tree/enumident2
https://github.com/hauntsaninja
hauntsaninjahttps://github.com/hauntsaninja
Apr 21, 2026https://github.com/python/mypy/pull/21281#issue-4300948412
Please reload this pagehttps://github.com/python/mypy/pull/21281
#21187https://github.com/python/mypy/issues/21187
#9003 (comment)https://github.com/python/mypy/issues/9003#issuecomment-778349487
Optional bytes type not narrowed after asserting equality #20701https://github.com/python/mypy/issues/20701
Please reload this pagehttps://github.com/python/mypy/pull/21281
https://github.com/apps/github-actions
github-actionshttps://github.com/apps/github-actions
Apr 21, 2026 https://github.com/python/mypy/pull/21281#ref-issue-4300949440
Check #21281 sterliakov/mypy-issues#289 https://github.com/sterliakov/mypy-issues/issues/289
https://github.com/hauntsaninja
Better narrowing for enums and other known types with equalityhttps://github.com/python/mypy/pull/21281/commits/e61527c4aeea57dfc3ba2072084ac693e7e15d97
e61527chttps://github.com/python/mypy/pull/21281/commits/e61527c4aeea57dfc3ba2072084ac693e7e15d97
https://github.com/hauntsaninja
hauntsaninjahttps://github.com/hauntsaninja
force-pushedhttps://github.com/python/mypy/compare/97034719469d6116e3ab5c5b8548db8c104eb858..e61527c4aeea57dfc3ba2072084ac693e7e15d97
9703471https://github.com/python/mypy/commit/97034719469d6116e3ab5c5b8548db8c104eb858
e61527chttps://github.com/python/mypy/commit/e61527c4aeea57dfc3ba2072084ac693e7e15d97
Compare https://github.com/python/mypy/compare/97034719469d6116e3ab5c5b8548db8c104eb858..e61527c4aeea57dfc3ba2072084ac693e7e15d97
April 21, 2026 07:30https://github.com/python/mypy/pull/21281#event-24707950460
https://github.com/apps/github-actions
Sign in to viewhttps://github.com/login?return_to=https%3A%2F%2Fgithub.com%2Fpython%2Fmypy%2Fpull%2F21281
https://github.com/hauntsaninja
hauntsaninjahttps://github.com/hauntsaninja
April 21, 2026 07:59https://github.com/python/mypy/pull/21281#event-24708887175
https://github.com/hauntsaninja
hauntsaninjahttps://github.com/hauntsaninja
Apr 21, 2026https://github.com/python/mypy/pull/21281#event-24726016054
https://github.com/hauntsaninja
hauntsaninjahttps://github.com/hauntsaninja
Apr 23, 2026 https://github.com/python/mypy/pull/21281#ref-issue-3887960566
1.20 and 2.0 Release Planning #20726 https://github.com/python/mypy/issues/20726
https://github.com/JukkaL
JukkaLhttps://github.com/JukkaL
Apr 24, 2026 https://github.com/python/mypy/pull/21281#pullrequestreview-4169902374
View reviewed changes https://github.com/python/mypy/pull/21281/files/e61527c4aeea57dfc3ba2072084ac693e7e15d97
JukkaLhttps://github.com/JukkaL
https://github.com/python/mypy/pull/21281#pullrequestreview-4169902374
Learn morehttps://docs.github.com/articles/managing-disruptive-comments/#hiding-a-comment
Please reload this pagehttps://github.com/python/mypy/pull/21281
mypy/checker.pyhttps://github.com/python/mypy/pull/21281/files/e61527c4aeea57dfc3ba2072084ac693e7e15d97#diff-f96a2d6138bc6cdf2a07c4d37f6071cc25c1631afc107e277a28d5b59fc0ef04
Please reload this pagehttps://github.com/python/mypy/pull/21281
mypy/checker.pyhttps://github.com/python/mypy/pull/21281/files/e61527c4aeea57dfc3ba2072084ac693e7e15d97#diff-f96a2d6138bc6cdf2a07c4d37f6071cc25c1631afc107e277a28d5b59fc0ef04
Please reload this pagehttps://github.com/python/mypy/pull/21281
test-data/unit/check-narrowing.testhttps://github.com/python/mypy/pull/21281/files/e61527c4aeea57dfc3ba2072084ac693e7e15d97#diff-0413401ad6a91bc5c66579455009ba606ee0ddfb0a78278c9e53618c83b53ed5
JukkaLhttps://github.com/JukkaL
Apr 24, 2026https://github.com/python/mypy/pull/21281#discussion_r3138009410
Learn morehttps://docs.github.com/articles/managing-disruptive-comments/#hiding-a-comment
Please reload this pagehttps://github.com/python/mypy/pull/21281
hauntsaninjahttps://github.com/hauntsaninja
Apr 24, 2026https://github.com/python/mypy/pull/21281#discussion_r3140199469
Learn morehttps://docs.github.com/articles/managing-disruptive-comments/#hiding-a-comment
Please reload this pagehttps://github.com/python/mypy/pull/21281
https://github.com/hauntsaninja
tmphttps://github.com/python/mypy/pull/21281/commits/697d83273fc2206640e0955ae4fa1e8dfa1d9f49
697d832https://github.com/python/mypy/pull/21281/commits/697d83273fc2206640e0955ae4fa1e8dfa1d9f49
https://github.com/apps/github-actions
github-actionshttps://github.com/apps/github-actions
Apr 24, 2026https://github.com/python/mypy/pull/21281#issuecomment-4316381540
mypy_primerhttps://github.com/hauntsaninja/mypy_primer
Please reload this pagehttps://github.com/python/mypy/pull/21281
https://github.com/hauntsaninja
hauntsaninjahttps://github.com/hauntsaninja
1e96fb7https://github.com/python/mypy/commit/1e96fb723793fd4c86fa8772d2e3516bd1668587
Apr 24, 2026https://github.com/python/mypy/pull/21281#event-24853980709
Please reload this pagehttps://github.com/python/mypy/pull/21281
https://github.com/hauntsaninja
hauntsaninjahttps://github.com/hauntsaninja
April 24, 2026 22:04https://github.com/python/mypy/pull/21281#event-24853981523
https://github.com/hauntsaninja
hauntsaninjahttps://github.com/hauntsaninja
Apr 28, 2026 https://github.com/python/mypy/pull/21281#ref-pullrequest-4339999678
Fix narrowing for AbstractSet and Mapping #21352 https://github.com/python/mypy/pull/21352
JukkaLhttps://github.com/JukkaL
Apr 28, 2026 https://github.com/python/mypy/pull/21281#ref-commit-c4b9a29
https://github.com/hauntsaninja
Fix narrowing for AbstractSet and Mapping (https://github.com/python/mypy/commit/c4b9a29505430433a6d8b4853bb3c02b42740017
#21352https://github.com/python/mypy/pull/21352
)https://github.com/python/mypy/commit/c4b9a29505430433a6d8b4853bb3c02b42740017
c4b9a29https://github.com/python/mypy/commit/c4b9a29505430433a6d8b4853bb3c02b42740017
#21281https://github.com/python/mypy/pull/21281
#21151https://github.com/python/mypy/pull/21151
JukkaLhttps://github.com/JukkaL
Apr 30, 2026 https://github.com/python/mypy/pull/21281#ref-commit-2c9ddae
https://github.com/hauntsaninja
https://github.com/JukkaL
Fix narrowing for AbstractSet and Mapping (https://github.com/python/mypy/commit/2c9ddae00bd6182c6327ed0b5baf89ff8ffd3197
#21352https://github.com/python/mypy/pull/21352
)https://github.com/python/mypy/commit/2c9ddae00bd6182c6327ed0b5baf89ff8ffd3197
2c9ddaehttps://github.com/python/mypy/commit/2c9ddae00bd6182c6327ed0b5baf89ff8ffd3197
#21281https://github.com/python/mypy/pull/21281
#21151https://github.com/python/mypy/pull/21151
https://github.co/hiddenchars
https://github.com/python/mypy/pull/{{ revealButtonHref }}
Sign up for freehttps://github.com/join?source=comment-repo
Sign in to commenthttps://github.com/login?return_to=https%3A%2F%2Fgithub.com%2Fpython%2Fmypy%2Fpull%2F21281
https://github.com/JukkaL
JukkaL https://github.com/JukkaL
https://github.com/python/mypy/pull/21281/files/e61527c4aeea57dfc3ba2072084ac693e7e15d97
[1.20 regression] Type narrowing is order sensitive in match-case statement with narrowed enum type https://github.com/python/mypy/issues/21187
Please reload this pagehttps://github.com/python/mypy/pull/21281
https://github.com/hauntsaninja
https://github.com/JukkaL
https://github.com
Termshttps://docs.github.com/site-policy/github-terms/github-terms-of-service
Privacyhttps://docs.github.com/site-policy/privacy-policies/github-privacy-statement
Securityhttps://github.com/security
Statushttps://www.githubstatus.com/
Communityhttps://github.community/
Docshttps://docs.github.com/
Contacthttps://support.github.com?tags=dotcom-footer

Viewport: width=device-width

URLs of crawlers that visited me.