TypeScript Properly propagate `ObjectFlags.NonInferrableType` onto non-aliased anonymous object types instantiations

fixes https://github.com/microsoft/TypeScript/issues/62345

Aug 27 '25 21:08 Andarist

@typescript-bot test it

Aug 27 '25 21:08 RyanCavanaugh

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

Aug 27 '25 21:08 typescript-bot

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

Everything looks the same!

You can check the log here.

Aug 27 '25 22:08 typescript-bot

@RyanCavanaugh Here are the results of running the user tests with tsc comparing main and refs/pull/62346/merge:

There were infrastructure failures potentially unrelated to your change:

1 instance of "Git clone failed"

Otherwise...

Everything looks good!

Aug 27 '25 22:08 typescript-bot

@RyanCavanaugh 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}	_{194,110k (± 0.96%)}	_{194,609k (± 0.95%)}	_~	_192,918k	_196,534k	_{p=0.378 n=6}
_{Parse Time}	_{1.30s (± 0.75%)}	_{1.31s (± 0.31%)}	_~	_1.31s	_1.32s	_{p=0.056 n=6}
_{Bind Time}	_{0.73s (± 0.56%)}	_{0.73s (± 0.56%)}	_~	_0.72s	_0.73s	_{p=1.000 n=6}
_{Check Time}	_{9.76s (± 0.19%)}	_{9.76s (± 0.50%)}	_~	_9.71s	_9.84s	_{p=1.000 n=6}
_{Emit Time}	_{2.73s (± 0.80%)}	_{2.75s (± 1.38%)}	_~	_2.70s	_2.80s	_{p=0.291 n=6}
_{Total Time}	_{14.52s (± 0.20%)}	_{14.55s (± 0.47%)}	_~	_14.47s	_14.67s	_{p=0.332 n=6}
_{angular-1 - node (v18.15.0, x64)}
_Errors	₁	₁	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_948,914	_948,914	_~	_~	_~	_{p=1.000 n=6}
_Types	_410,884	_410,884	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{1,246,608k (± 0.00%)}	_{1,246,637k (± 0.00%)}	_~	_1,246,581k	_1,246,682k	_{p=0.298 n=6}
_{Parse Time}	_{6.53s (± 0.99%)}	_{6.51s (± 0.91%)}	_~	_6.47s	_6.63s	_{p=0.466 n=6}
_{Bind Time}	_{1.87s (± 0.59%)}	_{1.87s (± 0.62%)}	_~	_1.85s	_1.88s	_{p=0.729 n=6}
_{Check Time}	_{32.24s (± 0.31%)}	_{32.24s (± 0.31%)}	_~	_32.14s	_32.41s	_{p=1.000 n=6}
_{Emit Time}	_{14.79s (± 0.36%)}	_{14.78s (± 0.50%)}	_~	_14.71s	_14.91s	_{p=0.517 n=6}
_{Total Time}	_{55.43s (± 0.22%)}	_{55.40s (± 0.23%)}	_~	_55.24s	_55.51s	_{p=0.936 n=6}
_{mui-docs - node (v18.15.0, x64)}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_2,545,948	_2,545,948	_~	_~	_~	_{p=1.000 n=6}
_Types	_902,562	_902,562	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{2,830,891k (± 0.01%)}	_{2,830,788k (± 0.00%)}	_~	_2,830,718k	_2,830,954k	_{p=0.093 n=6}
_{Parse Time}	_{8.76s (± 0.36%)}	_{8.77s (± 0.20%)}	_~	_8.75s	_8.80s	_{p=0.683 n=6}
_{Bind Time}	_{2.23s (± 0.72%)}	_{2.23s (± 0.73%)}	_~	_2.21s	_2.25s	_{p=0.934 n=6}
_{Check Time}	_{86.50s (± 1.67%)}	_{87.77s (± 0.93%)}	_~	_86.38s	_88.66s	_{p=0.066 n=6}
_{Emit Time}	_{0.62s (±124.07%)}	_{0.36s (±39.04%)}	_~	_0.30s	_0.65s	_{p=1.000 n=6}
_{Total Time}	_{98.10s (± 1.61%)}	_{99.13s (± 0.80%)}	_~	_97.70s	_99.98s	_{p=0.230 n=6}
_{self-build-src - node (v18.15.0, x64)}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_1,236,922	_1,236,923	_{+1 (+ 0.00%)}	_~	_~	_{p=0.001 n=6}
_Types	_259,638	_259,638	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{2,507,831k (±11.82%)}	_{2,447,319k (± 6.06%)}	_~	_2,386,546k	_2,750,149k	_{p=0.810 n=6}
_{Parse Time}	_{5.22s (± 1.30%)}	_{5.19s (± 1.05%)}	_~	_5.13s	_5.28s	_{p=0.748 n=6}
_{Bind Time}	_{1.81s (± 0.45%)}	_{1.80s (± 1.26%)}	_~	_1.75s	_1.81s	_{p=0.491 n=6}
_{Check Time}	_{35.17s (± 0.52%)}	_{34.97s (± 0.42%)}	_~	_34.70s	_35.11s	_{p=0.066 n=6}
_{Emit Time}	_{3.01s (± 2.54%)}	_{2.98s (± 1.23%)}	_~	_2.93s	_3.02s	_{p=0.521 n=6}
_{Total Time}	_{45.21s (± 0.46%)}	_{44.96s (± 0.33%)}	_~	_44.79s	_45.12s	_{p=0.066 n=6}
_{self-build-src-public-api - node (v18.15.0, x64)}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_1,236,922	_1,236,923	_{+1 (+ 0.00%)}	_~	_~	_{p=0.001 n=6}
_Types	_259,638	_259,638	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{2,818,872k (±14.05%)}	_{2,940,056k (±12.71%)}	_~	_2,457,031k	_3,182,171k	_{p=0.230 n=6}
_{Parse Time}	_{6.86s (± 1.08%)}	_{6.86s (± 1.78%)}	_~	_6.69s	_6.96s	_{p=1.000 n=6}
_{Bind Time}	_{2.19s (± 1.57%)}	_{2.19s (± 1.29%)}	_~	_2.16s	_2.24s	_{p=0.810 n=6}
_{Check Time}	_{42.48s (± 0.56%)}	_{42.40s (± 0.47%)}	_~	_42.16s	_42.70s	_{p=0.521 n=6}
_{Emit Time}	_{3.59s (± 4.83%)}	_{3.48s (± 0.48%)}	_~	_3.46s	_3.50s	_{p=0.470 n=6}
_{Total Time}	_{55.11s (± 0.62%)}	_{54.94s (± 0.50%)}	_~	_54.58s	_55.27s	_{p=0.298 n=6}
_{self-compiler - node (v18.15.0, x64)}
_Errors	₀	₀	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_262,416	_262,417	_{+1 (+ 0.00%)}	_~	_~	_{p=0.001 n=6}
_Types	_103,917	_103,917	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{441,719k (± 0.02%)}	_{441,676k (± 0.02%)}	_~	_441,605k	_441,776k	_{p=0.378 n=6}
_{Parse Time}	_{4.40s (± 0.87%)}	_{4.39s (± 0.84%)}	_~	_4.33s	_4.42s	_{p=0.568 n=6}
_{Bind Time}	_{1.64s (± 1.21%)}	_{1.63s (± 0.72%)}	_~	_1.62s	_1.65s	_{p=0.506 n=6}
_{Check Time}	_{23.39s (± 0.48%)}	_{23.43s (± 0.16%)}	_~	_23.38s	_23.49s	_{p=0.521 n=6}
_{Emit Time}	_{1.90s (± 0.86%)}	_{1.90s (± 0.72%)}	_~	_1.89s	_1.92s	_{p=0.564 n=6}
_{Total Time}	_{31.33s (± 0.39%)}	_{31.35s (± 0.08%)}	_~	_31.31s	_31.37s	_{p=0.374 n=6}
_{ts-pre-modules - node (v18.15.0, x64)}
_Errors	₇₂	₇₂	_~	_~	_~	_{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}	_{371,153k (± 0.03%)}	_{371,212k (± 0.03%)}	_~	_371,103k	_371,454k	_{p=0.093 n=6}
_{Parse Time}	_{2.88s (± 1.31%)}	_{2.87s (± 0.84%)}	_~	_2.85s	_2.92s	_{p=0.628 n=6}
_{Bind Time}	_{1.57s (± 1.04%)}	_{1.59s (± 0.66%)}	_~	_1.58s	_1.61s	_{p=0.061 n=6}
_{Check Time}	_{16.45s (± 0.38%)}	_{16.46s (± 0.40%)}	_~	_16.38s	_16.54s	_{p=0.809 n=6}
_{Emit Time}	_{0.00s (±154.76%)}	_0.00s	_~	_~	_~	_{p=0.174 n=6}
_{Total Time}	_{20.91s (± 0.38%)}	_{20.93s (± 0.41%)}	_~	_20.83s	_21.07s	_{p=0.873 n=6}
_{vscode - node (v18.15.0, x64)}
_Errors	₁	₁	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_3,874,623	_3,874,623	_~	_~	_~	_{p=1.000 n=6}
_Types	_1,221,094	_1,221,094	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{3,701,589k (± 0.01%)}	_{3,701,741k (± 0.01%)}	_~	_3,701,252k	_3,702,002k	_{p=0.471 n=6}
_{Parse Time}	_{18.79s (± 0.50%)}	_{18.75s (± 0.35%)}	_~	_18.66s	_18.84s	_{p=0.809 n=6}
_{Bind Time}	_{6.22s (± 2.84%)}	_{6.10s (± 1.67%)}	_~	_6.03s	_6.30s	_{p=0.260 n=6}
_{Check Time}	_{126.11s (± 2.87%)}	_{127.00s (± 4.03%)}	_~	_122.01s	_133.41s	_{p=0.936 n=6}
_{Emit Time}	_{44.65s (±22.78%)}	_{44.96s (±19.89%)}	_~	_37.34s	_55.73s	_{p=0.810 n=6}
_{Total Time}	_{195.76s (± 6.85%)}	_{196.81s (± 4.42%)}	_~	_184.69s	_205.25s	_{p=0.689 n=6}
_{webpack - node (v18.15.0, x64)}
_Errors	₃₇	₃₇	_~	_~	_~	_{p=1.000 n=6}
_Symbols	_356,094	_356,094	_~	_~	_~	_{p=1.000 n=6}
_Types	_156,860	_156,860	_~	_~	_~	_{p=1.000 n=6}
_{Memory used}	_{513,209k (± 0.04%)}	_{513,205k (± 0.04%)}	_~	_512,919k	_513,373k	_{p=0.689 n=6}
_{Parse Time}	_{4.60s (± 0.41%)}	_{4.60s (± 0.70%)}	_~	_4.57s	_4.66s	_{p=1.000 n=6}
_{Bind Time}	_{1.90s (± 0.52%)}	_{1.91s (± 0.97%)}	_~	_1.88s	_1.93s	_{p=0.118 n=6}
_{Check Time}	_{22.05s (± 0.82%)}	_{21.92s (± 0.54%)}	_~	_21.80s	_22.13s	_{p=0.230 n=6}
_{Emit Time}	_{0.00s (±244.70%)}	_{0.00s (±244.70%)}	_~	_0.00s	_0.01s	_{p=1.000 n=6}
_{Total Time}	_{28.55s (± 0.69%)}	_{28.44s (± 0.31%)}	_~	_28.35s	_28.59s	_{p=0.378 n=6}
_{xstate-main - node (v18.15.0, x64)}
_Errors	₃₀	₃₆	_{🔻+6 (+20.00%)}	_~	_~	_{p=0.001 n=6}
_Symbols	_666,064	_665,668	_{-396 (- 0.06%)}	_~	_~	_{p=0.001 n=6}
_Types	_199,729	_199,550	_{-179 (- 0.09%)}	_~	_~	_{p=0.001 n=6}
_{Memory used}	_{572,484k (± 0.03%)}	_{572,249k (± 0.02%)}	_~	_572,027k	_572,378k	_{p=0.065 n=6}
_{Parse Time}	_{5.29s (± 0.44%)}	_{5.33s (± 1.21%)}	_~	_5.22s	_5.42s	_{p=0.091 n=6}
_{Bind Time}	_{1.65s (± 0.91%)}	_{1.65s (± 0.62%)}	_~	_1.64s	_1.67s	_{p=0.867 n=6}
_{Check Time}	_{25.27s (± 1.98%)}	_{24.87s (± 1.12%)}	_~	_24.68s	_25.43s	_{p=0.229 n=6}
_{Emit Time}	_0.00s	_0.00s	_~	_~	_~	_{p=1.000 n=6}
_{Total Time}	_{32.21s (± 1.50%)}	_{31.85s (± 0.94%)}	_~	_31.66s	_32.45s	_{p=0.199 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

Aug 27 '25 22:08 typescript-bot

@RyanCavanaugh Here are the results of running the top 400 repos with tsc comparing main and refs/pull/62346/merge:

Everything looks good!

Aug 27 '25 23:08 typescript-bot

@typescript-bot pack this

Nov 05 '25 17:11 RyanCavanaugh

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

Command	Status	Results
`pack this`	✅ Started	✅ Results

Nov 05 '25 17:11 typescript-bot

Hey @RyanCavanaugh, I've packed this into an installable tgz. You can install it for testing by referencing it in your package.json like so:

{
    "devDependencies": {
        "typescript": "https://typescript.visualstudio.com/cf7ac146-d525-443c-b23c-0d58337efebc/_apis/build/builds/166456/artifacts?artifactName=tgz&fileId=FF881A7181E51FD746226C8F8B8AD2F99F484D2FAFBA4296A8441045ED0E10F602&fileName=/typescript-6.0.0-insiders.20251105.tgz"
    }
}

and then running npm install.

Nov 05 '25 17:11 typescript-bot