Keep accessors as accessors in emitted anonymous class declarations by Andarist · Pull Request #60853 · microsoft/TypeScript

Andarist · 2024-12-25T13:59:55Z

fixes #60672
fixes #44938
fixes #58790
fixes #61967

Andarist · 2025-01-01T20:35:57Z

src/compiler/checker.ts

                    }
                    if (!singleProp) {
                        singleProp = prop;
+                        propFlags = (prop.flags & SymbolFlags.Accessor) || SymbolFlags.Property;


Perhaps the accessor case should be handled through checkFlags. I'm worried that it would require looking carefully at all call sites that handle accessors to cover for this new case - but maybe I'm worried about it prematurely. Anyway, let me know what you think about it ;)

Andarist · 2025-01-01T20:39:46Z

src/compiler/checker.ts

+                        // classes created by mixins are represented as intersections and overriding a property in a derived class redefines it completely at runtime
+                        // so a get accessor can't be merged with a set accessor in a base class, for that reason the accessor flags are only used when they are the same in all consistuents


perhaps if I'd use a new CheckFlags.SyntheticAccessor that wouldn't really matter as much? I'm not sure if it's even that important of a rule to begin with, I just erred on the safer side of things and maintained the current behavior for this ambiguous case

…essors-on-emitted-anonymous-class-declarations

jakebailey · 2025-06-30T17:23:04Z

Doubtful this will catch anything, but

@typescript-bot test it

typescript-bot · 2025-06-30T17:23:09Z

Starting jobs; this comment will be updated as builds start and complete.

Command	Status	Results
`test top400`	✅ Started	✅ Results
`user test this`	✅ Started	✅ Results
`run dt`	✅ Started	✅ Results
`perf test this faster`	✅ Started	👀 Results

typescript-bot · 2025-06-30T17:44:51Z

Hey @jakebailey, the results of running the DT tests are ready.

Everything looks the same!

You can check the log here.

typescript-bot · 2025-06-30T18:01:25Z

@jakebailey Here are the results of running the user tests with tsc comparing main and refs/pull/60853/merge:

Everything looks good!

typescript-bot · 2025-06-30T18:16:30Z

@jakebailey
The results of the perf run you requested are in!

Here they are:

tsc

Comparison Report - baseline..pr

_Metric	_baseline	_pr	_Delta	_Best	_Worst	_p-value
_{Compiler-Unions - node (v18.15.0, x64)}
_Errors	₃₄	₃₄	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_62,370	_62,370	_~	_~	_~	_{p=1.000 n=6}
_Types	_50,386	_50,386	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{195,949k (± 0.71%)}	_{196,574k (± 0.03%)}	_~	_196,500k	_196,640k	_{p=0.298 n=6}
_{Parse Time}	_{1.60s (± 0.47%)}	_{1.60s (± 1.56%)}	_~	_1.57s	_1.63s	_{p=0.805 n=6}
_{Bind Time}	_{0.88s (± 1.02%)}	_{0.88s (± 1.18%)}	_~	_0.86s	_0.89s	_{p=0.673 n=6}
_{Check Time}	_{11.78s (± 0.37%)}	_{11.83s (± 0.94%)}	_~	_11.70s	_11.96s	_{p=0.521 n=6}
_{Emit Time}	_{3.33s (± 3.68%)}	_{3.27s (± 0.77%)}	_~	_3.23s	_3.31s	_{p=0.079 n=6}
_{Total Time}	_{17.58s (± 0.73%)}	_{17.58s (± 0.62%)}	_~	_17.47s	_17.71s	_{p=1.000 n=6}
_{angular-1 - node (v18.15.0, x64)}
_Errors	₅₆	₅₆	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_948,753	_948,753	_~	_~	_~	_{p=1.000 n=6}
_Types	_410,846	_410,846	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{1,225,207k (± 0.00%)}	_{1,225,195k (± 0.01%)}	_~	_1,225,077k	_1,225,257k	_{p=0.689 n=6}
_{Parse Time}	_{7.86s (± 1.11%)}	_{7.98s (± 0.48%)}	_~	_7.92s	_8.02s	_{p=0.064 n=6}
_{Bind Time}	_{2.28s (± 0.43%)}	_{2.29s (± 1.13%)}	_~	_2.24s	_2.31s	_{p=0.324 n=6}
_{Check Time}	_{37.95s (± 0.37%)}	_{38.01s (± 0.36%)}	_~	_37.85s	_38.19s	_{p=0.688 n=6}
_{Emit Time}	_{17.82s (± 0.66%)}	_{17.90s (± 0.90%)}	_~	_17.76s	_18.20s	_{p=0.423 n=6}
_{Total Time}	_{65.92s (± 0.43%)}	_{66.17s (± 0.29%)}	_~	_65.91s	_66.43s	_{p=0.128 n=6}
_{mui-docs - node (v18.15.0, x64)}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_2,509,183	_2,509,183	_~	_~	_~	_{p=1.000 n=6}
_Types	_892,716	_892,716	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{2,804,482k (± 0.00%)}	_{2,804,373k (± 0.00%)}	_~	_2,804,132k	_2,804,508k	_{p=0.173 n=6}
_{Parse Time}	_{10.53s (± 0.37%)}	_{10.49s (± 0.16%)}	_~	_10.47s	_10.51s	_{p=0.090 n=6}
_{Bind Time}	_{2.74s (± 0.15%)}	_{2.74s (± 0.84%)}	_~	_2.72s	_2.78s	_{p=0.498 n=6}
_{Check Time}	_{101.08s (± 0.35%)}	_{101.48s (± 2.19%)}	_~	_99.83s	_105.95s	_{p=0.230 n=6}
_{Emit Time}	_{0.37s (± 2.04%)}	_{0.37s (± 2.76%)}	_~	_0.36s	_0.39s	_{p=0.437 n=6}
_{Total Time}	_{114.71s (± 0.33%)}	_{115.09s (± 1.94%)}	_~	_113.40s	_119.59s	_{p=0.229 n=6}
_{self-build-src - node (v18.15.0, x64)}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_1,227,080	_1,227,095	_{+15 (+ 0.00%)}	_~	_~	_{p=0.001 n=6}
_Types	_267,443	_267,448	_{+5 (+ 0.00%)}	_~	_~	_{p=0.001 n=6}
_{Memory used}	_{2,781,556k (±12.57%)}	_{2,756,565k (±13.68%)}	_~	_2,364,729k	_3,097,767k	_{p=1.000 n=6}
_{Parse Time}	_{6.61s (± 1.29%)}	_{6.59s (± 1.40%)}	_~	_6.46s	_6.69s	_{p=0.575 n=6}
_{Bind Time}	_{2.17s (± 0.63%)}	_{2.16s (± 1.49%)}	_~	_2.12s	_2.21s	_{p=0.193 n=6}
_{Check Time}	_{42.62s (± 0.63%)}	_{42.75s (± 0.88%)}	_~	_41.99s	_42.96s	_{p=0.298 n=6}
_{Emit Time}	_{3.40s (± 2.56%)}	_{3.54s (± 2.04%)}	_{🔻+0.14s (+ 4.27%)}	_3.44s	_3.60s	_{p=0.045 n=6}
_{Total Time}	_{54.81s (± 0.70%)}	_{55.05s (± 0.78%)}	_~	_54.18s	_55.30s	_{p=0.471 n=6}
_{self-build-src-public-api - node (v18.15.0, x64)}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_1,227,080	_1,227,095	_{+15 (+ 0.00%)}	_~	_~	_{p=0.001 n=6}
_Types	_267,443	_267,448	_{+5 (+ 0.00%)}	_~	_~	_{p=0.001 n=6}
_{Memory used}	_{2,674,885k (±14.05%)}	_{2,796,572k (±14.27%)}	_~	_2,431,253k	_3,161,462k	_{p=0.471 n=6}
_{Parse Time}	_{6.82s (± 1.24%)}	_{6.87s (± 0.56%)}	_~	_6.81s	_6.90s	_{p=0.378 n=6}
_{Bind Time}	_{2.21s (± 1.31%)}	_{2.21s (± 1.06%)}	_~	_2.18s	_2.24s	_{p=1.000 n=6}
_{Check Time}	_{42.80s (± 0.53%)}	_{42.78s (± 0.46%)}	_~	_42.58s	_43.02s	_{p=0.810 n=6}
_{Emit Time}	_{3.60s (± 3.35%)}	_{3.53s (± 2.78%)}	_~	_3.41s	_3.70s	_{p=0.297 n=6}
_{Total Time}	_{55.43s (± 0.53%)}	_{55.39s (± 0.50%)}	_~	_55.04s	_55.71s	_{p=0.873 n=6}
_{self-compiler - node (v18.15.0, x64)}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_262,529	_262,544	_{+15 (+ 0.01%)}	_~	_~	_{p=0.001 n=6}
_Types	_107,150	_107,155	_{+5 (+ 0.00%)}	_~	_~	_{p=0.001 n=6}
_{Memory used}	_{441,796k (± 0.01%)}	_{441,855k (± 0.03%)}	_~	_441,640k	_442,078k	_{p=0.093 n=6}
_{Parse Time}	_{3.52s (± 0.47%)}	_{3.54s (± 0.94%)}	_~	_3.50s	_3.59s	_{p=0.226 n=6}
_{Bind Time}	_{1.32s (± 1.07%)}	_{1.32s (± 1.11%)}	_~	_1.30s	_1.34s	_{p=0.870 n=6}
_{Check Time}	_{18.92s (± 0.28%)}	_{18.84s (± 0.32%)}	_~	_18.77s	_18.95s	_{p=0.063 n=6}
_{Emit Time}	_{1.53s (± 1.62%)}	_{1.51s (± 1.16%)}	_~	_1.49s	_1.54s	_{p=0.413 n=6}
_{Total Time}	_{25.28s (± 0.24%)}	_{25.22s (± 0.37%)}	_~	_25.10s	_25.36s	_{p=0.261 n=6}
_{ts-pre-modules - node (v18.15.0, x64)}
_Errors	₇₁	₇₁	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_225,367	_225,367	_~	_~	_~	_{p=1.000 n=6}
_Types	_94,290	_94,290	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{371,088k (± 0.01%)}	_{371,143k (± 0.02%)}	_~	_371,080k	_371,303k	_{p=0.298 n=6}
_{Parse Time}	_{2.88s (± 0.97%)}	_{2.88s (± 0.87%)}	_~	_2.83s	_2.90s	_{p=1.000 n=6}
_{Bind Time}	_{1.61s (± 1.28%)}	_{1.59s (± 0.77%)}	_~	_1.58s	_1.61s	_{p=0.365 n=6}
_{Check Time}	_{16.36s (± 0.33%)}	_{16.34s (± 0.30%)}	_~	_16.27s	_16.39s	_{p=0.571 n=6}
_{Emit Time}	_0.00s	_0.00s	_~	_~	_~	_{p=1.000 n=6}
_{Total Time}	_{20.85s (± 0.34%)}	_{20.81s (± 0.37%)}	_~	_20.73s	_20.90s	_{p=0.466 n=6}
_{vscode - node (v18.15.0, x64)}
_Errors	₃₃	₃₃	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_3,498,707	_3,498,707	_~	_~	_~	_{p=1.000 n=6}
_Types	_1,176,728	_1,176,728	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{3,548,716k (± 0.00%)}	_{3,548,740k (± 0.00%)}	_~	_3,548,497k	_3,548,913k	_{p=0.810 n=6}
_{Parse Time}	_{18.80s (± 3.28%)}	_{18.47s (± 0.26%)}	_~	_18.40s	_18.53s	_{p=0.230 n=6}
_{Bind Time}	_{6.00s (± 0.33%)}	_{5.99s (± 0.57%)}	_~	_5.94s	_6.02s	_{p=0.803 n=6}
_{Check Time}	_{120.15s (± 4.48%)}	_{115.69s (± 3.07%)}	_~	_113.63s	_122.89s	_{p=0.298 n=6}
_{Emit Time}	_{37.17s (± 2.67%)}	_{36.40s (± 1.93%)}	_~	_36.02s	_37.83s	_{p=0.471 n=6}
_{Total Time}	_{182.11s (± 3.51%)}	_{176.54s (± 2.43%)}	_~	_174.11s	_185.23s	_{p=0.378 n=6}
_{webpack - node (v18.15.0, x64)}
_Errors	₂	₂	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_318,019	_318,019	_~	_~	_~	_{p=1.000 n=6}
_Types	_137,705	_137,705	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{472,300k (± 0.02%)}	_{472,088k (± 0.01%)}	_{-212k (- 0.04%)}	_472,009k	_472,187k	_{p=0.008 n=6}
_{Parse Time}	_{4.35s (± 0.52%)}	_{4.36s (± 1.12%)}	_~	_4.30s	_4.45s	_{p=0.685 n=6}
_{Bind Time}	_{1.78s (± 0.69%)}	_{1.77s (± 0.97%)}	_~	_1.75s	_1.80s	_{p=0.137 n=6}
_{Check Time}	_{20.78s (± 0.52%)}	_{20.69s (± 0.41%)}	_~	_20.63s	_20.84s	_{p=0.108 n=6}
_{Emit Time}	_0.00s	_0.00s	_~	_~	_~	_{p=1.000 n=6}
_{Total Time}	_{26.92s (± 0.46%)}	_{26.82s (± 0.48%)}	_~	_26.70s	_27.05s	_{p=0.128 n=6}
_{xstate-main - node (v18.15.0, x64)}
_Errors	₃₀	₃₀	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_665,978	_665,978	_~	_~	_~	_{p=1.000 n=6}
_Types	_199,345	_199,345	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{570,374k (± 0.01%)}	_{570,277k (± 0.03%)}	_~	_569,930k	_570,378k	_{p=0.230 n=6}
_{Parse Time}	_{4.25s (± 0.77%)}	_{4.25s (± 0.72%)}	_~	_4.22s	_4.30s	_{p=1.000 n=6}
_{Bind Time}	_{1.34s (± 0.73%)}	_{1.34s (± 0.87%)}	_~	_1.33s	_1.36s	_{p=1.000 n=6}
_{Check Time}	_{19.93s (± 0.38%)}	_{19.94s (± 0.30%)}	_~	_19.89s	_20.04s	_{p=0.936 n=6}
_{Emit Time}	_0.00s	_0.00s	_~	_~	_~	_{p=1.000 n=6}
_{Total Time}	_{25.52s (± 0.36%)}	_{25.54s (± 0.25%)}	_~	_25.47s	_25.64s	_{p=0.936 n=6}

System info unknown

Hosts

node (v18.15.0, x64)

Scenarios

Compiler-Unions - node (v18.15.0, x64)
angular-1 - node (v18.15.0, x64)
mui-docs - node (v18.15.0, x64)
self-build-src - node (v18.15.0, x64)
self-build-src-public-api - node (v18.15.0, x64)
self-compiler - node (v18.15.0, x64)
ts-pre-modules - node (v18.15.0, x64)
vscode - node (v18.15.0, x64)
webpack - node (v18.15.0, x64)
xstate-main - node (v18.15.0, x64)

_Benchmark	_Name	_Iterations
_Current	_pr	₆
_Baseline	_baseline	₆

Developer Information:

Download Benchmarks

typescript-bot · 2025-06-30T19:04:58Z

@jakebailey Here are the results of running the top 400 repos with tsc comparing main and refs/pull/60853/merge:

Everything looks good!

src/compiler/checker.ts

Keep accessors as accessors in emitted anonymous class declarations

3fe512a

typescript-bot assigned rbuckton Dec 25, 2024

typescript-bot added For Backlog Bug PRs that fix a backlog bug For Milestone Bug PRs that fix a bug with a specific milestone labels Dec 25, 2024

Propagate accessor flags in intersected properties

1baa828

Andarist force-pushed the keep-accessors-as-accessors-on-emitted-anonymous-class-declarations branch from d466c50 to 1baa828 Compare January 1, 2025 19:11

fixed a thing

161e1ca

Andarist commented Jan 1, 2025

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Andarist added 2 commits June 30, 2025 10:40

Merge remote-tracking branch 'origin/main' into keep-accessors-as-acc…

e38b30d

…essors-on-emitted-anonymous-class-declarations

add extra test case

d29a82a

Andarist mentioned this pull request Jun 30, 2025

Merging Classes With Getters Converts Into a Property #61967

Closed

add extra test case

b43f9dd

Andarist force-pushed the keep-accessors-as-accessors-on-emitted-anonymous-class-declarations branch from bfbf4b6 to b43f9dd Compare June 30, 2025 09:30

rbuckton removed their assignment Jun 30, 2025

DanielRosenwasser approved these changes Jun 30, 2025

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github-project-automation bot moved this from Not started to Needs merge in PR Backlog Jun 30, 2025

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src/compiler/checker.ts Outdated Show resolved Hide resolved

split comment into multiple lines

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jakebailey approved these changes Jun 30, 2025

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jakebailey merged commit c35b143 into microsoft:main Jun 30, 2025
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github-project-automation bot moved this from Needs merge to Done in PR Backlog Jun 30, 2025

Andarist mentioned this pull request Oct 4, 2025

Port "Keep accessors as accessors in emitted anonymous class declarations" microsoft/typescript-go#1822

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Keep accessors as accessors in emitted anonymous class declarations#60853

Keep accessors as accessors in emitted anonymous class declarations#60853
jakebailey merged 7 commits intomicrosoft:mainfrom
Andarist:keep-accessors-as-accessors-on-emitted-anonymous-class-declarations

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		// classes created by mixins are represented as intersections and overriding a property in a derived class redefines it completely at runtime
		// so a get accessor can't be merged with a set accessor in a base class, for that reason the accessor flags are only used when they are the same in all consistuents

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