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GeezerVison is showing github.com — CFA for dependent parameters typed by generic constraints by ahejlsberg · Pull Request #48411 · microsoft/TypeScript

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@ahejlsberg

@ahejlsberg Anders Hejlsberg (ahejlsberg) commented Mar 24, 2022

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Fixes #48345.

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Anders Hejlsberg (ahejlsberg) added 2 commits March 24, 2022 16:41
@ahejlsberg
Obtain apparent type in parameter destructuring check
70f6175
@ahejlsberg
Add regression test
44e8d72
@typescript-bot TypeScript Bot (typescript-bot) assigned Anders Hejlsberg (ahejlsberg) Mar 24, 2022
@typescript-bot TypeScript Bot (typescript-bot) added Author: Team For Milestone Bug PRs that fix a bug with a specific milestone labels Mar 24, 2022
@ahejlsberg

Anders Hejlsberg (ahejlsberg) commented Mar 24, 2022

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TypeScript Bot (@typescript-bot) test this
TypeScript Bot (@typescript-bot) user test this inline
TypeScript Bot (@typescript-bot) run dt
TypeScript Bot (@typescript-bot) perf test faster
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@typescript-bot

TypeScript Bot (typescript-bot) commented Mar 24, 2022 •
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Heya Anders Hejlsberg (@ahejlsberg), I've started to run the diff-based community code test suite on this PR at 44e8d72. You can monitor the build here.

Update: The results are in!
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TypeScript Bot (typescript-bot) commented Mar 24, 2022 •
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Heya Anders Hejlsberg (@ahejlsberg), I've started to run the parallelized Definitely Typed test suite on this PR at 44e8d72. You can monitor the build here.
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TypeScript Bot (typescript-bot) commented Mar 24, 2022 •
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Heya Anders Hejlsberg (@ahejlsberg), I've started to run the abridged perf test suite on this PR at 44e8d72. You can monitor the build here.

Update: The results are in!
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TypeScript Bot (typescript-bot) commented Mar 24, 2022 •
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Heya Anders Hejlsberg (@ahejlsberg), I've started to run the extended test suite on this PR at 44e8d72. You can monitor the build here.
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@ahejlsberg
Anders Hejlsberg (ahejlsberg) requested a review from Ryan Cavanaugh (RyanCavanaugh) March 24, 2022 23:53
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TypeScript Bot (typescript-bot) commented Mar 25, 2022

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Anders Hejlsberg (@ahejlsberg)
The results of the perf run you requested are in!

Here they are:

Comparison Report - main..48411

Metric main 48411 Delta Best Worst
Angular - node (v14.15.1, x64)
Memory used 332,462k (± 0.01%) 332,480k (± 0.01%) +18k (+ 0.01%) 332,434k 332,546k
Parse Time 2.02s (± 0.45%) 2.02s (± 0.24%) -0.00s (- 0.10%) 2.01s 2.03s
Bind Time 0.87s (± 0.60%) 0.87s (± 0.92%) -0.00s (- 0.12%) 0.85s 0.89s
Check Time 5.61s (± 0.42%) 5.61s (± 0.44%) +0.00s (+ 0.02%) 5.55s 5.66s
Emit Time 6.25s (± 0.44%) 6.29s (± 0.58%) +0.04s (+ 0.61%) 6.20s 6.37s
Total Time 14.75s (± 0.30%) 14.79s (± 0.38%) +0.04s (+ 0.25%) 14.64s 14.89s
Compiler-Unions - node (v14.15.1, x64)
Memory used 194,944k (± 0.38%) 194,520k (± 0.56%) -424k (- 0.22%) 191,255k 195,285k
Parse Time 0.86s (± 0.75%) 0.86s (± 0.61%) +0.00s (+ 0.12%) 0.85s 0.87s
Bind Time 0.56s (± 0.80%) 0.56s (± 0.80%) 0.00s ( 0.00%) 0.55s 0.57s
Check Time 7.51s (± 0.64%) 7.54s (± 0.65%) +0.03s (+ 0.36%) 7.46s 7.67s
Emit Time 2.50s (± 0.86%) 2.49s (± 0.79%) -0.01s (- 0.28%) 2.45s 2.54s
Total Time 11.42s (± 0.46%) 11.45s (± 0.42%) +0.02s (+ 0.18%) 11.38s 11.57s
Monaco - node (v14.15.1, x64)
Memory used 325,416k (± 0.01%) 325,425k (± 0.01%) +9k (+ 0.00%) 325,391k 325,474k
Parse Time 1.58s (± 0.60%) 1.57s (± 0.25%) -0.01s (- 0.44%) 1.56s 1.58s
Bind Time 0.77s (± 0.38%) 0.77s (± 0.64%) +0.00s (+ 0.26%) 0.77s 0.79s
Check Time 5.51s (± 0.28%) 5.49s (± 0.53%) -0.02s (- 0.38%) 5.40s 5.54s
Emit Time 3.31s (± 0.51%) 3.29s (± 0.61%) -0.02s (- 0.64%) 3.24s 3.32s
Total Time 11.17s (± 0.20%) 11.12s (± 0.31%) -0.05s (- 0.43%) 11.00s 11.18s
TFS - node (v14.15.1, x64)
Memory used 288,905k (± 0.01%) 288,894k (± 0.00%) -11k (- 0.00%) 288,853k 288,911k
Parse Time 1.32s (± 1.17%) 1.32s (± 1.58%) +0.00s (+ 0.23%) 1.29s 1.38s
Bind Time 0.73s (± 0.92%) 0.73s (± 0.64%) +0.00s (+ 0.41%) 0.72s 0.74s
Check Time 5.15s (± 0.38%) 5.16s (± 0.49%) +0.00s (+ 0.10%) 5.08s 5.21s
Emit Time 3.45s (± 1.71%) 3.50s (± 2.32%) +0.05s (+ 1.42%) 3.36s 3.66s
Total Time 10.65s (± 0.62%) 10.71s (± 1.08%) +0.06s (+ 0.56%) 10.48s 10.95s
material-ui - node (v14.15.1, x64)
Memory used 453,635k (± 0.01%) 453,586k (± 0.04%) -48k (- 0.01%) 452,939k 453,713k
Parse Time 1.86s (± 0.26%) 1.85s (± 0.41%) -0.00s (- 0.11%) 1.84s 1.88s
Bind Time 0.71s (± 0.91%) 0.70s (± 1.08%) -0.00s (- 0.56%) 0.69s 0.72s
Check Time 20.38s (± 0.70%) 20.51s (± 0.64%) +0.13s (+ 0.62%) 20.33s 20.88s
Emit Time 0.00s (± 0.00%) 0.00s (± 0.00%) 0.00s ( NaN%) 0.00s 0.00s
Total Time 22.95s (± 0.62%) 23.07s (± 0.60%) +0.12s (+ 0.51%) 22.89s 23.48s
xstate - node (v14.15.1, x64)
Memory used 534,101k (± 0.00%) 534,087k (± 0.00%) -14k (- 0.00%) 534,043k 534,118k
Parse Time 2.56s (± 0.38%) 2.57s (± 0.48%) +0.00s (+ 0.20%) 2.54s 2.60s
Bind Time 1.15s (± 0.66%) 1.15s (± 0.72%) +0.00s (+ 0.09%) 1.13s 1.17s
Check Time 1.51s (± 0.40%) 1.52s (± 0.49%) +0.01s (+ 0.33%) 1.51s 1.54s
Emit Time 0.07s (± 0.00%) 0.07s (± 0.00%) 0.00s ( 0.00%) 0.07s 0.07s
Total Time 5.29s (± 0.17%) 5.31s (± 0.35%) +0.01s (+ 0.26%) 5.27s 5.36s
System
Machine Namets-ci-ubuntu
Platformlinux 4.4.0-210-generic
Architecturex64
Available Memory16 GB
Available Memory4 GB
CPUs4 × Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz
Hosts
  • node (v14.15.1, x64)
Scenarios
  • Angular - node (v14.15.1, x64)
  • Compiler-Unions - node (v14.15.1, x64)
  • Monaco - node (v14.15.1, x64)
  • TFS - node (v14.15.1, x64)
  • material-ui - node (v14.15.1, x64)
  • xstate - node (v14.15.1, x64)
Benchmark Name Iterations
Current 48411 10
Baseline main 10

Developer Information:

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@typescript-bot

TypeScript Bot (typescript-bot) commented Mar 25, 2022

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Anders Hejlsberg (@ahejlsberg)
Great news! no new errors were found between main..refs/pull/48411/merge
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Andarist
Mateusz Burzyński (Andarist) reviewed Mar 25, 2022
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Comment thread src/compiler/checker.ts
const contextualSignature = getContextualSignature(func);
if (contextualSignature && contextualSignature.parameters.length === 1 && signatureHasRestParameter(contextualSignature)) {
const restType = getTypeOfSymbol(contextualSignature.parameters[0]);
const restType = getReducedApparentType(getTypeOfSymbol(contextualSignature.parameters[0]));

@Andarist Mateusz Burzyński (Andarist) Mar 25, 2022

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A very easy fix indeed 😅

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@ahejlsberg
Merge branch 'main' into fix48345
342116c
@ahejlsberg

Anders Hejlsberg (ahejlsberg) commented Mar 25, 2022

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TypeScript Bot (@typescript-bot) run dt
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@awerlogus

Michael Borislav (awerlogus) commented Mar 25, 2022

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For test suite:

function a<T extends 'a' | 'b'> (arg: T) {
  if (arg === 'a') {
    // Expected: 'a'
    // Got: T extends "a" | "b"
    arg
  }
}
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RyanCavanaugh
Ryan Cavanaugh (RyanCavanaugh) approved these changes Mar 30, 2022
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@ahejlsberg
Anders Hejlsberg (ahejlsberg) merged commit fd601dd into main Mar 30, 2022
@ahejlsberg
Anders Hejlsberg (ahejlsberg) deleted the fix48345 branch March 30, 2022 23:33
Sidharth Vinod (sidharthv96) added a commit to sidharthv96/TypeScript that referenced this pull request Apr 1, 2022
@sidharthv96
Merge remote-tracking branch 'upstream/main' into fix/46149
e149cc3 
* upstream/main: (473 commits)
  Correct node used for isDefinition calculation (microsoft#48499)
  fix(48405): emit dummy members from a mapped type (microsoft#48481)
  CFA for dependent parameters typed by generic constraints (microsoft#48411)
  No contextual typing from return types for boolean literals (microsoft#48380)
  fix(47733): omit JSDoc comment template suggestion on node with existing JSDoc (microsoft#47748)
  Ensure that we copy empty NodeArrays during transform (microsoft#48490)
  Add a new compiler option `moduleSuffixes` to expand the node module resolver's search algorithm (microsoft#48189)
  feat(27615): Add missing member fix should work for type literals (microsoft#47212)
  Add label details to completion entry (microsoft#48429)
  Enable method signature completion for object literals (microsoft#48168)
  Fix string literal completions when a partially-typed string fixes inference to a type parameter (microsoft#48410)
  fix(48445): show errors on type-only import/export specifiers in JavaScript files (microsoft#48449)
  Fix newline inserted in empty block at end of formatting range (microsoft#48463)
  Prevent looking up symbol for as const from triggering an error (microsoft#48464)
  Revise accessor resolution logic and error reporting (microsoft#48459)
  fix(48166): skip checking module.exports in a truthiness call expression (microsoft#48337)
  LEGO: Merge pull request 48450
  LEGO: Merge pull request 48436
  fix(48031): show circularity error for self referential get accessor annotations (microsoft#48050)
  Revert "Fix contextual discrimination for omitted members (microsoft#43937)" (microsoft#48426)
  ...
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Reviewers

@RyanCavanaugh Ryan Cavanaugh (RyanCavanaugh) RyanCavanaugh approved these changes
+1 more reviewer
@Andarist Mateusz Burzyński (Andarist) Andarist left review comments
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@ahejlsberg Anders Hejlsberg (ahejlsberg)

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Successfully merging this pull request may close these issues.

Control Flow Analysis for Dependent Parameters doesn't work when the parameters are generic

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5 participants

@ahejlsberg @typescript-bot @awerlogus @RyanCavanaugh @Andarist
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