Ignore self tail calls when collecting the return type of a function by RyanCavanaugh · Pull Request #53995 · microsoft/TypeScript

Ryan Cavanaugh (RyanCavanaugh) · 2023-04-24T16:06:38Z

Fixes longstanding complaints about simple recursive functions!

When you have a recursive function with a base case and a self-recursive tail call, there's no reason we can't correctly handle it. With this PR:

function fn1(n: number) {
    if (n === 0) {
        return 3; // <- contributes number
    } else {
        return fn1(n - 1); // <- ignored
    }
}

and

// fn2(): never
function fn2() {
    return fn2();
}

I believe the blocker we had to doing this originally was the lack of a never type, but now we have that, it's straightforward to do this and everything just sort of works out.

Ryan Cavanaugh (RyanCavanaugh) · 2023-04-24T16:32:33Z

TypeScript Bot (@typescript-bot) test this
TypeScript Bot (@typescript-bot) test top100
TypeScript Bot (@typescript-bot) user test this
TypeScript Bot (@typescript-bot) user test tsserver
TypeScript Bot (@typescript-bot) test tsserver top100
TypeScript Bot (@typescript-bot) run dt
TypeScript Bot (@typescript-bot) perf test this
TypeScript Bot (@typescript-bot) pack this

TypeScript Bot (typescript-bot) · 2023-04-24T16:32:37Z

Heya Ryan Cavanaugh (@RyanCavanaugh), I've started to run the diff-based user code test suite (tsserver) on this PR at b0f4ad7. You can monitor the build here.

Update: The results are in!

TypeScript Bot (typescript-bot) · 2023-04-24T16:32:37Z

Heya Ryan Cavanaugh (@RyanCavanaugh), I've started to run the diff-based user code test suite on this PR at b0f4ad7. You can monitor the build here.

Update: The results are in!

TypeScript Bot (typescript-bot) · 2023-04-24T16:32:37Z

Heya Ryan Cavanaugh (@RyanCavanaugh), I've started to run the diff-based top-repos suite (tsserver) on this PR at b0f4ad7. You can monitor the build here.

Update: The results are in!

TypeScript Bot (typescript-bot) · 2023-04-24T16:32:37Z

Heya Ryan Cavanaugh (@RyanCavanaugh), I've started to run the diff-based top-repos suite on this PR at b0f4ad7. You can monitor the build here.

Update: The results are in!

TypeScript Bot (typescript-bot) · 2023-04-24T16:32:37Z

Heya Ryan Cavanaugh (@RyanCavanaugh), I've started to run the extended test suite on this PR at b0f4ad7. You can monitor the build here.

TypeScript Bot (typescript-bot) · 2023-04-24T16:32:37Z

Heya Ryan Cavanaugh (@RyanCavanaugh), I've started to run the tarball bundle task on this PR at b0f4ad7. You can monitor the build here.

TypeScript Bot (typescript-bot) · 2023-04-24T16:32:37Z

Heya Ryan Cavanaugh (@RyanCavanaugh), I've started to run the perf test suite on this PR at b0f4ad7. You can monitor the build here.

Update: The results are in!

TypeScript Bot (typescript-bot) · 2023-04-24T16:32:37Z

Heya Ryan Cavanaugh (@RyanCavanaugh), I've started to run the parallelized Definitely Typed test suite on this PR at b0f4ad7. You can monitor the build here.

Update: The results are in!

TypeScript Bot (typescript-bot) · 2023-04-24T16:34:39Z

Hey Ryan Cavanaugh (@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/153152/artifacts?artifactName=tgz&fileId=EE5C88BAA3F9E077D7C6EDC8C661D997CD43910E4BDD25941947912FA32B8B9A02&fileName=/typescript-5.1.0-insiders.20230424.tgz"
    }
}

and then running npm install.

TypeScript Bot (typescript-bot) · 2023-04-24T16:43:02Z

Ryan Cavanaugh (@RyanCavanaugh) Here are the results of running the user test suite comparing main and refs/pull/53995/merge:

There were infrastructure failures potentially unrelated to your change:

1 instance of "Package install failed"

Otherwise...

Something interesting changed - please have a look.

Details

debug

/mnt/ts_downloads/debug/tsconfig.json

[NEW] error TS2367: This comparison appears to be unintentional because the types '"undefined"' and '"object"' have no overlap.
- /mnt/ts_downloads/debug/node_modules/debug/src/browser.js(100,10)

TypeScript Bot (typescript-bot) · 2023-04-24T16:47:20Z

Heya Ryan Cavanaugh (@RyanCavanaugh), I've run the RWC suite on this PR - assuming you're on the TS core team, you can view the resulting diff here.

David Blass (ssalbdivad) · 2023-04-24T16:47:24Z

This looks great! Should be able to remove quite a few unnecessary explicit return signatures 😊

TypeScript Bot (typescript-bot) · 2023-04-24T16:47:37Z

Ryan Cavanaugh (@RyanCavanaugh) Here are the results of running the user test suite comparing main and refs/pull/53995/merge:

Everything looks good!

Bruce Pascoe (fatcerberus) · 2023-04-24T17:15:32Z

Inferring never for the infinitely recursive case (by simply ignoring the tail call) is a nice bonus 😃

Bruce Pascoe (fatcerberus) · 2023-04-24T17:18:36Z

Ignore tail calls when collecting the return type of a function

Question: What happens here?

function foo() {
    return bar();  // not mutually recursive
}

Nothing in the OP suggests this is only for self-recursive functions, so I want to check.

Ryan Cavanaugh (RyanCavanaugh) · 2023-04-24T17:26:22Z

Just an imprecise title; this is only about self-recursive tail calls to the same function as the one being checked. So this doesn't enable automatic checking of e.g. mutual recursion either

TypeScript Bot (typescript-bot) · 2023-04-24T17:28:58Z

Ryan Cavanaugh (@RyanCavanaugh)
The results of the perf run you requested are in!

Here they are:

Compiler

Comparison Report - main..53995

_Metric	_main	₅₃₉₉₅	_Delta	_Best	_Worst	_p-value
_{Angular - node (v18.10.0, x64)}
_{Memory used}	_{365,777k (± 0.01%)}	_{365,834k (± 0.01%)}	_{+57k (+ 0.02%)}	_365,808k	_365,870k	_{p=0.013 n=6}
_{Parse Time}	_{3.40s (± 0.77%)}	_{3.39s (± 0.74%)}	_~	_3.36s	_3.42s	_{p=0.808 n=6}
_{Bind Time}	_{1.11s (± 0.37%)}	_{1.11s (± 0.47%)}	_~	_1.10s	_1.11s	_{p=0.114 n=6}
_{Check Time}	_{8.73s (± 0.27%)}	_{8.72s (± 0.50%)}	_~	_8.65s	_8.78s	_{p=0.686 n=6}
_{Emit Time}	_{7.45s (± 0.65%)}	_{7.42s (± 0.73%)}	_~	_7.38s	_7.51s	_{p=0.257 n=6}
_{Total Time}	_{20.69s (± 0.30%)}	_{20.64s (± 0.30%)}	_~	_20.56s	_20.72s	_{p=0.297 n=6}
_{Compiler-Unions - node (v18.10.0, x64)}
_{Memory used}	_{192,869k (± 1.52%)}	_{192,862k (± 1.53%)}	_~	_190,892k	_196,801k	_{p=0.936 n=6}
_{Parse Time}	_{1.48s (± 1.01%)}	_{1.50s (± 0.00%)}	_{+0.02s (+ 1.12%)}	_1.50s	_1.50s	_{p=0.009 n=6}
_{Bind Time}	_{0.77s (± 0.53%)}	_{0.77s (± 0.00%)}	_~	_0.77s	_0.77s	_{p=0.405 n=6}
_{Check Time}	_{9.53s (± 0.34%)}	_{9.54s (± 0.34%)}	_~	_9.50s	_9.58s	_{p=0.572 n=6}
_{Emit Time}	_{2.76s (± 0.62%)}	_{2.77s (± 2.11%)}	_~	_2.68s	_2.86s	_{p=0.514 n=6}
_{Total Time}	_{14.54s (± 0.19%)}	_{14.58s (± 0.40%)}	_~	_14.49s	_14.64s	_{p=0.226 n=6}
_{Monaco - node (v18.10.0, x64)}
_{Memory used}	_{346,510k (± 0.01%)}	_{346,531k (± 0.01%)}	_~	_346,498k	_346,559k	_{p=0.336 n=6}
_{Parse Time}	_{2.59s (± 0.67%)}	_{2.58s (± 1.13%)}	_~	_2.53s	_2.61s	_{p=0.466 n=6}
_{Bind Time}	_{1.00s (± 0.41%)}	_{1.00s (± 0.52%)}	_~	_0.99s	_1.00s	_{p=0.114 n=6}
_{Check Time}	_{7.14s (± 0.41%)}	_{7.15s (± 0.21%)}	_~	_7.13s	_7.17s	_{p=0.870 n=6}
_{Emit Time}	_{4.23s (± 1.57%)}	_{4.23s (± 0.55%)}	_~	_4.19s	_4.25s	_{p=0.373 n=6}
_{Total Time}	_{14.97s (± 0.69%)}	_{14.96s (± 0.20%)}	_~	_14.93s	_15.00s	_{p=0.629 n=6}
_{TFS - node (v18.10.0, x64)}
_{Memory used}	_{300,716k (± 0.01%)}	_{300,720k (± 0.01%)}	_~	_300,681k	_300,752k	_{p=0.748 n=6}
_{Parse Time}	_{2.05s (± 1.13%)}	_{2.06s (± 0.59%)}	_~	_2.04s	_2.07s	_{p=0.934 n=6}
_{Bind Time}	_{1.13s (± 1.07%)}	_{1.14s (± 0.66%)}	_~	_1.13s	_1.15s	_{p=0.502 n=6}
_{Check Time}	_{6.61s (± 0.54%)}	_{6.59s (± 0.48%)}	_~	_6.54s	_6.62s	_{p=0.288 n=6}
_{Emit Time}	_{3.88s (± 0.57%)}	_{3.90s (± 0.42%)}	_~	_3.88s	_3.92s	_{p=0.325 n=6}
_{Total Time}	_{13.68s (± 0.37%)}	_{13.68s (± 0.27%)}	_~	_13.63s	_13.72s	_{p=1.000 n=6}
_{material-ui - node (v18.10.0, x64)}
_{Memory used}	_{482,317k (± 0.02%)}	_{482,319k (± 0.01%)}	_~	_482,269k	_482,362k	_{p=0.936 n=6}
_{Parse Time}	_{3.09s (± 0.43%)}	_{3.10s (± 0.53%)}	_~	_3.09s	_3.13s	_{p=0.081 n=6}
_{Bind Time}	_{0.90s (± 0.83%)}	_{0.91s (± 0.45%)}	_~	_0.90s	_0.91s	_{p=0.100 n=6}
_{Check Time}	_{16.82s (± 0.51%)}	_{16.76s (± 0.35%)}	_~	_16.69s	_16.85s	_{p=0.261 n=6}
_{Emit Time}	_{0.00s (± 0.00%)}	_{0.00s (± 0.00%)}	_~	_0.00s	_0.00s	_{p=1.000 n=6}
_{Total Time}	_{20.82s (± 0.43%)}	_{20.78s (± 0.25%)}	_~	_20.72s	_20.86s	_{p=0.470 n=6}
_{xstate - node (v18.10.0, x64)}
_{Memory used}	_{562,925k (± 0.01%)}	_{562,981k (± 0.01%)}	_~	_562,920k	_563,078k	_{p=0.066 n=6}
_{Parse Time}	_{3.81s (± 0.66%)}	_{3.84s (± 0.85%)}	_~	_3.78s	_3.86s	_{p=0.123 n=6}
_{Bind Time}	_{1.64s (± 0.51%)}	_{1.64s (± 0.74%)}	_~	_1.62s	_1.65s	_{p=0.459 n=6}
_{Check Time}	_{2.81s (± 0.42%)}	_{2.81s (± 0.61%)}	_~	_2.79s	_2.83s	_{p=0.730 n=6}
_{Emit Time}	_{0.08s (± 0.00%)}	_{0.08s (± 0.00%)}	_~	_0.08s	_0.08s	_{p=1.000 n=6}
_{Total Time}	_{8.35s (± 0.30%)}	_{8.37s (± 0.37%)}	_~	_8.32s	_8.40s	_{p=0.196 n=6}
_{Angular - node (v16.17.1, x64)}
_{Memory used}	_{365,207k (± 0.01%)}	_{365,187k (± 0.01%)}	_~	_365,170k	_365,234k	_{p=0.229 n=6}
_{Parse Time}	_{3.54s (± 0.43%)}	_{3.53s (± 0.75%)}	_~	_3.50s	_3.57s	_{p=0.256 n=6}
_{Bind Time}	_{1.18s (± 0.54%)}	_{1.17s (± 0.00%)}	_{-0.01s (- 0.85%)}	_1.17s	_1.17s	_{p=0.008 n=6}
_{Check Time}	_{9.54s (± 0.65%)}	_{9.55s (± 0.52%)}	_~	_9.50s	_9.63s	_{p=0.747 n=6}
_{Emit Time}	_{7.91s (± 0.29%)}	_{7.90s (± 0.27%)}	_~	_7.87s	_7.93s	_{p=0.686 n=6}
_{Total Time}	_{22.17s (± 0.35%)}	_{22.15s (± 0.24%)}	_~	_22.09s	_22.24s	_{p=0.936 n=6}
_{Compiler-Unions - node (v16.17.1, x64)}
_{Memory used}	_{192,615k (± 0.04%)}	_{192,660k (± 0.03%)}	_~	_192,581k	_192,740k	_{p=0.261 n=6}
_{Parse Time}	_{1.59s (± 0.47%)}	_{1.59s (± 0.93%)}	_~	_1.56s	_1.60s	_{p=1.000 n=6}
_{Bind Time}	_{0.83s (± 1.01%)}	_{0.82s (± 0.63%)}	_~	_0.82s	_0.83s	_{p=0.923 n=6}
_{Check Time}	_{10.22s (± 0.12%)}	_{10.21s (± 0.56%)}	_~	_10.12s	_10.29s	_{p=1.000 n=6}
_{Emit Time}	_{3.01s (± 0.39%)}	_{3.03s (± 0.25%)}	_{+0.02s (+ 0.55%)}	_3.02s	_3.04s	_{p=0.032 n=6}
_{Total Time}	_{15.64s (± 0.05%)}	_{15.65s (± 0.39%)}	_~	_15.56s	_15.72s	_{p=1.000 n=6}
_{Monaco - node (v16.17.1, x64)}
_{Memory used}	_{345,780k (± 0.00%)}	_{345,812k (± 0.00%)}	_{+33k (+ 0.01%)}	_345,802k	_345,830k	_{p=0.006 n=6}
_{Parse Time}	_{2.71s (± 0.19%)}	_{2.72s (± 0.33%)}	_~	_2.71s	_2.73s	_{p=0.190 n=6}
_{Bind Time}	_{1.08s (± 0.77%)}	_{1.08s (± 0.38%)}	_~	_1.08s	_1.09s	_{p=0.527 n=6}
_{Check Time}	_{7.84s (± 0.10%)}	_{7.84s (± 0.22%)}	_~	_7.81s	_7.86s	_{p=0.867 n=6}
_{Emit Time}	_{4.45s (± 0.28%)}	_{4.46s (± 0.80%)}	_~	_4.41s	_4.50s	_{p=0.628 n=6}
_{Total Time}	_{16.09s (± 0.17%)}	_{16.10s (± 0.36%)}	_~	_16.02s	_16.18s	_{p=0.629 n=6}
_{TFS - node (v16.17.1, x64)}
_{Memory used}	_{300,081k (± 0.00%)}	_{300,068k (± 0.01%)}	_~	_300,042k	_300,088k	_{p=0.173 n=6}
_{Parse Time}	_{2.15s (± 0.46%)}	_{2.16s (± 0.59%)}	_~	_2.14s	_2.17s	_{p=0.214 n=6}
_{Bind Time}	_{1.24s (± 0.41%)}	_{1.24s (± 1.22%)}	_~	_1.22s	_1.26s	_{p=0.282 n=6}
_{Check Time}	_{7.24s (± 0.38%)}	_{7.25s (± 0.48%)}	_~	_7.19s	_7.30s	_{p=0.570 n=6}
_{Emit Time}	_{4.40s (± 1.06%)}	_{4.38s (± 0.67%)}	_~	_4.34s	_4.41s	_{p=0.681 n=6}
_{Total Time}	_{15.03s (± 0.49%)}	_{15.01s (± 0.39%)}	_~	_14.92s	_15.09s	_{p=0.747 n=6}
_{material-ui - node (v16.17.1, x64)}
_{Memory used}	_{481,566k (± 0.01%)}	_{481,543k (± 0.00%)}	_~	_481,506k	_481,566k	_{p=0.199 n=6}
_{Parse Time}	_{3.23s (± 0.13%)}	_{3.24s (± 0.54%)}	_~	_3.22s	_3.26s	_{p=1.000 n=6}
_{Bind Time}	_{0.94s (± 0.80%)}	_{0.94s (± 0.43%)}	_~	_0.93s	_0.94s	_{p=1.000 n=6}
_{Check Time}	_{17.90s (± 0.65%)}	_{17.80s (± 0.75%)}	_~	_17.67s	_18.04s	_{p=0.149 n=6}
_{Emit Time}	_{0.00s (± 0.00%)}	_{0.00s (± 0.00%)}	_~	_0.00s	_0.00s	_{p=1.000 n=6}
_{Total Time}	_{22.07s (± 0.52%)}	_{21.97s (± 0.56%)}	_~	_21.86s	_22.20s	_{p=0.126 n=6}
_{xstate - node (v16.17.1, x64)}
_{Memory used}	_{560,542k (± 0.02%)}	_{560,548k (± 0.01%)}	_~	_560,503k	_560,628k	_{p=0.378 n=6}
_{Parse Time}	_{4.00s (± 0.34%)}	_{3.99s (± 0.25%)}	_~	_3.98s	_4.00s	_{p=0.801 n=6}
_{Bind Time}	_{1.77s (± 0.23%)}	_{1.77s (± 0.00%)}	_~	_1.77s	_1.77s	_{p=0.405 n=6}
_{Check Time}	_{3.04s (± 0.34%)}	_{3.05s (± 0.27%)}	_~	_3.04s	_3.06s	_{p=0.865 n=6}
_{Emit Time}	_{0.09s (± 0.00%)}	_{0.09s (± 0.00%)}	_~	_0.09s	_0.09s	_{p=1.000 n=6}
_{Total Time}	_{8.90s (± 0.26%)}	_{8.89s (± 0.17%)}	_~	_8.87s	_8.91s	_{p=0.806 n=6}
_{Angular - node (v14.21.3, x64)}
_{Memory used}	_{359,203k (± 0.00%)}	_{359,205k (± 0.00%)}	_~	_359,197k	_359,216k	_{p=0.873 n=6}
_{Parse Time}	_{3.66s (± 0.64%)}	_{3.66s (± 0.30%)}	_~	_3.65s	_3.68s	_{p=0.808 n=6}
_{Bind Time}	_{1.22s (± 0.67%)}	_{1.22s (± 0.80%)}	_~	_1.21s	_1.23s	_{p=0.394 n=6}
_{Check Time}	_{9.97s (± 0.46%)}	_{9.94s (± 0.47%)}	_~	_9.89s	_10.01s	_{p=0.377 n=6}
_{Emit Time}	_{8.30s (± 0.58%)}	_{8.25s (± 0.90%)}	_~	_8.16s	_8.37s	_{p=0.228 n=6}
_{Total Time}	_{23.14s (± 0.22%)}	_{23.07s (± 0.33%)}	_~	_23.02s	_23.22s	_{p=0.077 n=6}
_{Compiler-Unions - node (v14.21.3, x64)}
_{Memory used}	_{188,064k (± 0.01%)}	_{188,023k (± 0.02%)}	_~	_187,982k	_188,056k	_{p=0.054 n=6}
_{Parse Time}	_{1.60s (± 0.56%)}	_{1.59s (± 0.66%)}	_~	_1.58s	_1.61s	_{p=0.452 n=6}
_{Bind Time}	_{0.85s (± 0.61%)}	_{0.85s (± 0.74%)}	_~	_0.84s	_0.86s	_{p=0.386 n=6}
_{Check Time}	_{10.35s (± 0.38%)}	_{10.35s (± 0.22%)}	_~	_10.32s	_10.38s	_{p=0.936 n=6}
_{Emit Time}	_{3.18s (± 0.99%)}	_{3.14s (± 0.20%)}	_{-0.04s (- 1.26%)}	_3.13s	_3.15s	_{p=0.016 n=6}
_{Total Time}	_{15.98s (± 0.23%)}	_{15.93s (± 0.13%)}	_{-0.04s (- 0.27%)}	_15.91s	_15.96s	_{p=0.044 n=6}
_{Monaco - node (v14.21.3, x64)}
_{Memory used}	_{340,875k (± 0.01%)}	_{340,881k (± 0.01%)}	_~	_340,834k	_340,928k	_{p=0.575 n=6}
_{Parse Time}	_{2.80s (± 0.35%)}	_{2.79s (± 0.53%)}	_~	_2.78s	_2.81s	_{p=0.315 n=6}
_{Bind Time}	_{1.11s (± 1.23%)}	_{1.11s (± 0.74%)}	_~	_1.10s	_1.12s	_{p=0.282 n=6}
_{Check Time}	_{8.15s (± 0.34%)}	_{8.14s (± 0.39%)}	_~	_8.11s	_8.18s	_{p=0.627 n=6}
_{Emit Time}	_{4.70s (± 0.77%)}	_{4.70s (± 0.52%)}	_~	_4.66s	_4.73s	_{p=1.000 n=6}
_{Total Time}	_{16.76s (± 0.34%)}	_{16.74s (± 0.39%)}	_~	_16.65s	_16.81s	_{p=0.575 n=6}
_{TFS - node (v14.21.3, x64)}
_{Memory used}	_{295,256k (± 0.00%)}	_{295,240k (± 0.01%)}	_{-17k (- 0.01%)}	_295,214k	_295,266k	_{p=0.045 n=6}
_{Parse Time}	_{2.40s (± 0.97%)}	_{2.40s (± 0.70%)}	_~	_2.37s	_2.42s	_{p=0.366 n=6}
_{Bind Time}	_{1.07s (± 0.48%)}	_{1.06s (± 0.38%)}	_~	_1.06s	_1.07s	_{p=0.112 n=6}
_{Check Time}	_{7.58s (± 0.45%)}	_{7.54s (± 0.47%)}	_~	_7.50s	_7.58s	_{p=0.148 n=6}
_{Emit Time}	_{4.33s (± 0.95%)}	_{4.31s (± 0.82%)}	_~	_4.26s	_4.34s	_{p=0.373 n=6}
_{Total Time}	_{15.38s (± 0.43%)}	_{15.31s (± 0.39%)}	_~	_15.23s	_15.37s	_{p=0.063 n=6}
_{material-ui - node (v14.21.3, x64)}
_{Memory used}	_{477,146k (± 0.00%)}	_{477,147k (± 0.00%)}	_~	_477,112k	_477,166k	_{p=0.810 n=6}
_{Parse Time}	_{3.33s (± 0.25%)}	_{3.33s (± 0.52%)}	_~	_3.31s	_3.36s	_{p=0.548 n=6}
_{Bind Time}	_{1.00s (± 0.41%)}	_{1.00s (± 0.63%)}	_~	_0.99s	_1.01s	_{p=0.673 n=6}
_{Check Time}	_{18.70s (± 0.42%)}	_{18.74s (± 0.49%)}	_~	_18.64s	_18.89s	_{p=0.471 n=6}
_{Emit Time}	_{0.00s (± 0.00%)}	_{0.00s (± 0.00%)}	_~	_0.00s	_0.00s	_{p=1.000 n=6}
_{Total Time}	_{23.02s (± 0.35%)}	_{23.07s (± 0.40%)}	_~	_22.96s	_23.22s	_{p=0.261 n=6}
_{xstate - node (v14.21.3, x64)}
_{Memory used}	_{549,556k (± 0.00%)}	_{549,560k (± 0.01%)}	_~	_549,534k	_549,608k	_{p=0.575 n=6}
_{Parse Time}	_{4.21s (± 1.01%)}	_{4.20s (± 0.49%)}	_~	_4.17s	_4.23s	_{p=0.566 n=6}
_{Bind Time}	_{1.62s (± 4.08%)}	_{1.63s (± 2.71%)}	_~	_1.57s	_1.66s	_{p=0.868 n=6}
_{Check Time}	_{3.20s (± 0.51%)}	_{3.20s (± 0.46%)}	_~	_3.18s	_3.22s	_{p=0.517 n=6}
_{Emit Time}	_{0.09s (± 0.00%)}	_{0.09s (± 0.00%)}	_~	_0.09s	_0.09s	_{p=1.000 n=6}
_{Total Time}	_{9.12s (± 0.46%)}	_{9.12s (± 0.78%)}	_~	_9.02s	_9.18s	_{p=0.809 n=6}

System

_{Machine Name}	_ts-ci-ubuntu
_Platform	_{linux 5.4.0-135-generic}
_Architecture	_x64
_{Available Memory}	_{16 GB}
_{Available Memory}	_{15 GB}
_CPUs	_{4 × Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz}

Hosts

node (v18.10.0, x64)
node (v16.17.1, x64)
node (v14.21.3, x64)

Scenarios

Angular - node (v18.10.0, x64)
Angular - node (v16.17.1, x64)
Angular - node (v14.21.3, x64)
Compiler-Unions - node (v18.10.0, x64)
Compiler-Unions - node (v16.17.1, x64)
Compiler-Unions - node (v14.21.3, x64)
Monaco - node (v18.10.0, x64)
Monaco - node (v16.17.1, x64)
Monaco - node (v14.21.3, x64)
TFS - node (v18.10.0, x64)
TFS - node (v16.17.1, x64)
TFS - node (v14.21.3, x64)
material-ui - node (v18.10.0, x64)
material-ui - node (v16.17.1, x64)
material-ui - node (v14.21.3, x64)
xstate - node (v18.10.0, x64)
xstate - node (v16.17.1, x64)
xstate - node (v14.21.3, x64)

_Benchmark	_Name	_Iterations
_Current	₅₃₉₉₅	₆
_Baseline	_main	₆

TSServer

Comparison Report - main..53995

_Metric	_main	₅₃₉₉₅	_Delta	_Best	_Worst	_p-value
_{Compiler-UnionsTSServer - node (v18.10.0, x64)}
_{Req 1 - updateOpen}	_{2,530ms (± 0.96%)}	_{2,529ms (± 0.23%)}	_~	_2,522ms	_2,536ms	_{p=0.873 n=6}
_{Req 2 - geterr}	_{5,642ms (± 1.43%)}	_{5,649ms (± 0.26%)}	_~	_5,629ms	_5,670ms	_{p=0.378 n=6}
_{Req 3 - references}	_{344ms (± 0.66%)}	_{342ms (± 0.50%)}	_~	_340ms	_344ms	_{p=0.512 n=6}
_{Req 4 - navto}	_{283ms (± 0.48%)}	_{282ms (± 0.27%)}	_~	_281ms	_283ms	_{p=0.273 n=6}
_{Req 5 - completionInfo count}	_{1,356 (± 0.00%)}	_{1,356 (± 0.00%)}	_~	_1,356	_1,356	_{p=1.000 n=6}
_{Req 5 - completionInfo}	_{82ms (± 8.47%)}	_{85ms (± 1.05%)}	_~	_84ms	_86ms	_{p=0.673 n=6}
_{CompilerTSServer - node (v18.10.0, x64)}
_{Req 1 - updateOpen}	_{2,645ms (± 1.07%)}	_{2,631ms (± 1.08%)}	_~	_2,591ms	_2,679ms	_{p=0.229 n=6}
_{Req 2 - geterr}	_{4,225ms (± 2.30%)}	_{4,292ms (± 0.62%)}	_~	_4,242ms	_4,318ms	_{p=0.065 n=6}
_{Req 3 - references}	_{348ms (± 0.57%)}	_{347ms (± 0.43%)}	_~	_345ms	_349ms	_{p=0.216 n=6}
_{Req 4 - navto}	_{290ms (± 0.47%)}	_{289ms (± 0.51%)}	_~	_287ms	_291ms	_{p=0.120 n=6}
_{Req 5 - completionInfo count}	_{1,518 (± 0.00%)}	_{1,518 (± 0.00%)}	_~	_1,518	_1,518	_{p=1.000 n=6}
_{Req 5 - completionInfo}	_{65ms (± 5.50%)}	_{62ms (± 0.83%)}	_~	_62ms	_63ms	_{p=0.143 n=6}
_{xstateTSServer - node (v18.10.0, x64)}
_{Req 1 - updateOpen}	_{3,074ms (± 0.57%)}	_{3,075ms (± 0.63%)}	_~	_3,039ms	_3,091ms	_{p=1.000 n=6}
_{Req 2 - geterr}	_{1,611ms (± 1.37%)}	_{1,613ms (± 1.36%)}	_~	_1,596ms	_1,642ms	_{p=0.936 n=6}
_{Req 3 - references}	_{108ms (± 1.23%)}	_{109ms (± 1.82%)}	_~	_107ms	_111ms	_{p=0.675 n=6}
_{Req 4 - navto}	_{362ms (± 0.17%)}	_{363ms (± 0.52%)}	_~	_361ms	_366ms	_{p=1.000 n=6}
_{Req 5 - completionInfo count}	_{2,862 (± 0.00%)}	_{2,862 (± 0.00%)}	_~	_2,862	_2,862	_{p=1.000 n=6}
_{Req 5 - completionInfo}	_{372ms (± 1.92%)}	_{374ms (± 1.10%)}	_~	_367ms	_379ms	_{p=0.628 n=6}
_{Compiler-UnionsTSServer - node (v16.17.1, x64)}
_{Req 1 - updateOpen}	_{2,655ms (± 0.54%)}	_{2,665ms (± 0.78%)}	_~	_2,635ms	_2,691ms	_{p=0.199 n=6}
_{Req 2 - geterr}	_{6,150ms (± 0.42%)}	_{6,155ms (± 0.49%)}	_~	_6,120ms	_6,205ms	_{p=0.936 n=6}
_{Req 3 - references}	_{354ms (± 0.59%)}	_{355ms (± 1.03%)}	_~	_350ms	_359ms	_{p=0.748 n=6}
_{Req 4 - navto}	_{285ms (± 1.74%)}	_{286ms (± 1.16%)}	_~	_282ms	_292ms	_{p=0.223 n=6}
_{Req 5 - completionInfo count}	_{1,356 (± 0.00%)}	_{1,356 (± 0.00%)}	_~	_1,356	_1,356	_{p=1.000 n=6}
_{Req 5 - completionInfo}	_{87ms (± 6.96%)}	_{87ms (± 6.73%)}	_~	_81ms	_93ms	_{p=0.623 n=6}
_{CompilerTSServer - node (v16.17.1, x64)}
_{Req 1 - updateOpen}	_{2,815ms (± 0.79%)}	_{2,816ms (± 0.46%)}	_~	_2,790ms	_2,823ms	_{p=0.810 n=6}
_{Req 2 - geterr}	_{4,650ms (± 0.20%)}	_{4,655ms (± 0.35%)}	_~	_4,636ms	_4,683ms	_{p=0.689 n=6}
_{Req 3 - references}	_{364ms (± 0.60%)}	_{363ms (± 0.45%)}	_~	_361ms	_365ms	_{p=0.415 n=6}
_{Req 4 - navto}	_{285ms (± 0.69%)}	_{286ms (± 0.26%)}	_~	_285ms	_287ms	_{p=0.365 n=6}
_{Req 5 - completionInfo count}	_{1,518 (± 0.00%)}	_{1,518 (± 0.00%)}	_~	_1,518	_1,518	_{p=1.000 n=6}
_{Req 5 - completionInfo}	_{68ms (± 2.22%)}	_{67ms (± 0.94%)}	_~	_66ms	_68ms	_{p=0.591 n=6}
_{xstateTSServer - node (v16.17.1, x64)}
_{Req 1 - updateOpen}	_{3,208ms (± 0.33%)}	_{3,215ms (± 0.37%)}	_~	_3,202ms	_3,236ms	_{p=0.422 n=6}
_{Req 2 - geterr}	_{1,760ms (± 0.64%)}	_{1,766ms (± 0.71%)}	_~	_1,750ms	_1,785ms	_{p=0.470 n=6}
_{Req 3 - references}	_{124ms (± 0.94%)}	_{124ms (± 1.44%)}	_~	_121ms	_126ms	_{p=0.742 n=6}
_{Req 4 - navto}	_{343ms (± 1.14%)}	_{340ms (± 0.42%)}	_~	_338ms	_342ms	_{p=0.085 n=6}
_{Req 5 - completionInfo count}	_{2,862 (± 0.00%)}	_{2,862 (± 0.00%)}	_~	_2,862	_2,862	_{p=1.000 n=6}
_{Req 5 - completionInfo}	_{394ms (± 1.23%)}	_{393ms (± 0.47%)}	_~	_390ms	_395ms	_{p=0.936 n=6}
_{Compiler-UnionsTSServer - node (v14.21.3, x64)}
_{Req 1 - updateOpen}	_{2,771ms (± 0.46%)}	_{2,776ms (± 0.17%)}	_~	_2,771ms	_2,782ms	_{p=0.378 n=6}
_{Req 2 - geterr}	_{6,339ms (± 1.40%)}	_{6,287ms (± 0.79%)}	_~	_6,203ms	_6,353ms	_{p=0.378 n=6}
_{Req 3 - references}	_{367ms (± 0.92%)}	_{368ms (± 0.64%)}	_~	_365ms	_370ms	_{p=0.685 n=6}
_{Req 4 - navto}	_{290ms (± 0.83%)}	_{290ms (± 0.64%)}	_~	_288ms	_292ms	_{p=0.806 n=6}
_{Req 5 - completionInfo count}	_{1,356 (± 0.00%)}	_{1,356 (± 0.00%)}	_~	_1,356	_1,356	_{p=1.000 n=6}
_{Req 5 - completionInfo}	_{100ms (± 4.96%)}	_{99ms (± 5.57%)}	_~	_92ms	_105ms	_{p=0.936 n=6}
_{CompilerTSServer - node (v14.21.3, x64)}
_{Req 1 - updateOpen}	_{2,946ms (± 0.80%)}	_{2,964ms (± 0.54%)}	_~	_2,943ms	_2,980ms	_{p=0.128 n=6}
_{Req 2 - geterr}	_{4,561ms (± 2.08%)}	_{4,528ms (± 0.52%)}	_~	_4,493ms	_4,548ms	_{p=0.873 n=6}
_{Req 3 - references}	_{377ms (± 0.98%)}	_{374ms (± 0.63%)}	_~	_371ms	_377ms	_{p=0.199 n=6}
_{Req 4 - navto}	_{297ms (± 0.70%)}	_{298ms (± 0.17%)}	_~	_298ms	_299ms	_{p=0.059 n=6}
_{Req 5 - completionInfo count}	_{1,518 (± 0.00%)}	_{1,518 (± 0.00%)}	_~	_1,518	_1,518	_{p=1.000 n=6}
_{Req 5 - completionInfo}	_{77ms (± 1.64%)}	_{76ms (± 1.07%)}	_~	_75ms	_77ms	_{p=0.281 n=6}
_{xstateTSServer - node (v14.21.3, x64)}
_{Req 1 - updateOpen}	_{3,457ms (± 1.32%)}	_{3,458ms (± 0.35%)}	_~	_3,446ms	_3,479ms	_{p=0.872 n=6}
_{Req 2 - geterr}	_{1,870ms (± 0.60%)}	_{1,860ms (± 0.56%)}	_~	_1,844ms	_1,876ms	_{p=0.149 n=6}
_{Req 3 - references}	_{152ms (± 7.66%)}	_{142ms (± 6.10%)}	_~	_137ms	_159ms	_{p=0.141 n=6}
_{Req 4 - navto}	_{397ms (± 1.59%)}	_{394ms (± 0.80%)}	_~	_390ms	_399ms	_{p=0.574 n=6}
_{Req 5 - completionInfo count}	_{2,862 (± 0.00%)}	_{2,862 (± 0.00%)}	_~	_2,862	_2,862	_{p=1.000 n=6}
_{Req 5 - completionInfo}	_{433ms (± 1.12%)}	_{432ms (± 2.05%)}	_~	_417ms	_444ms	_{p=0.936 n=6}

System

_{Machine Name}	_ts-ci-ubuntu
_Platform	_{linux 5.4.0-135-generic}
_Architecture	_x64
_{Available Memory}	_{16 GB}
_{Available Memory}	_{15 GB}
_CPUs	_{4 × Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz}

Hosts

node (v18.10.0, x64)
node (v16.17.1, x64)
node (v14.21.3, x64)

Scenarios

Compiler-UnionsTSServer - node (v18.10.0, x64)
Compiler-UnionsTSServer - node (v16.17.1, x64)
Compiler-UnionsTSServer - node (v14.21.3, x64)
CompilerTSServer - node (v18.10.0, x64)
CompilerTSServer - node (v16.17.1, x64)
CompilerTSServer - node (v14.21.3, x64)
xstateTSServer - node (v18.10.0, x64)
xstateTSServer - node (v16.17.1, x64)
xstateTSServer - node (v14.21.3, x64)

_Benchmark	_Name	_Iterations
_Current	₅₃₉₉₅	₆
_Baseline	_main	₆

Startup

Comparison Report - main..53995

_Metric	_main	₅₃₉₉₅	_Delta	_Best	_Worst	_p-value
_{tsc-startup - node (v16.17.1, x64)}
_{Execution time}	_{141.63ms (± 0.20%)}	_{142.15ms (± 0.21%)}	_{+0.52ms (+ 0.37%)}	_141.49ms	_147.65ms	_{p=0.000 n=600}
_{tsserver-startup - node (v16.17.1, x64)}
_{Execution time}	_{220.23ms (± 0.15%)}	_{221.14ms (± 0.13%)}	_{+0.92ms (+ 0.42%)}	_220.27ms	_224.57ms	_{p=0.000 n=600}
_{tsserverlibrary-startup - node (v16.17.1, x64)}
_{Execution time}	_{221.88ms (± 0.18%)}	_{222.64ms (± 0.16%)}	_{+0.75ms (+ 0.34%)}	_221.86ms	_229.91ms	_{p=0.000 n=600}
_{typescript-startup - node (v16.17.1, x64)}
_{Execution time}	_{203.81ms (± 0.15%)}	_{204.46ms (± 0.15%)}	_{+0.65ms (+ 0.32%)}	_203.67ms	_208.47ms	_{p=0.000 n=600}

System

_{Machine Name}	_ts-ci-ubuntu
_Platform	_{linux 5.4.0-135-generic}
_Architecture	_x64
_{Available Memory}	_{16 GB}
_{Available Memory}	_{15 GB}
_CPUs	_{4 × Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz}

Hosts

node (v16.17.1, x64)

Scenarios

tsc-startup - node (v16.17.1, x64)
tsserver-startup - node (v16.17.1, x64)
tsserverlibrary-startup - node (v16.17.1, x64)
typescript-startup - node (v16.17.1, x64)

_Benchmark	_Name	_Iterations
_Current	₅₃₉₉₅	₆
_Baseline	_main	₆

Developer Information:

Download Benchmark

TypeScript Bot (typescript-bot) · 2023-04-24T18:17:36Z

Ryan Cavanaugh (@RyanCavanaugh) Here are the results of running the top-repos suite comparing main and refs/pull/53995/merge:

Everything looks good!

TypeScript Bot (typescript-bot) · 2023-04-24T18:33:30Z

Hey Ryan Cavanaugh (@RyanCavanaugh), the results of running the DT tests are ready.
Everything looks the same!
You can check the log here.

Jake Bailey (jakebailey) · 2023-04-24T19:28:22Z

TypeScript Bot (@typescript-bot) pack this

TypeScript Bot (typescript-bot) · 2023-04-24T19:28:24Z

Heya Jake Bailey (@jakebailey), I've started to run the tarball bundle task on this PR at b0f4ad7. You can monitor the build here.

TypeScript Bot (typescript-bot) · 2023-04-24T19:30:07Z

Hey Jake Bailey (@jakebailey), 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/153179/artifacts?artifactName=tgz&fileId=EE5C88BAA3F9E077D7C6EDC8C661D997CD43910E4BDD25941947912FA32B8B9A02&fileName=/typescript-5.1.0-insiders.20230424.tgz"
    }
}

and then running npm install.

There is also a playground for this build and an npm module you can use via "typescript": "npm:@typescript-deploys/pr-build@5.1.0-pr-53995-22".;

TypeScript Bot (typescript-bot) · 2023-04-24T19:38:52Z

Ryan Cavanaugh (@RyanCavanaugh) Here are the results of running the top-repos suite comparing main and refs/pull/53995/merge:

Everything looks good!

Noel Kim (nnnnoel) · 2023-04-25T07:00:51Z

Ryan Cavanaugh (@RyanCavanaugh) is this PR also can be resolved for generator function?

Ignore self-calls when collecting the return type of a function

b0f4ad7

TypeScript Bot (typescript-bot) assigned Ryan Cavanaugh (RyanCavanaugh) Apr 24, 2023

TypeScript Bot (typescript-bot) added Author: Team For Uncommitted Bug PR for untriaged, rejected, closed or missing bug labels Apr 24, 2023

Ryan Cavanaugh (RyanCavanaugh) changed the title ~~Ignore tail calls when collecting the return type of a function~~ Ignore self tail calls when collecting the return type of a function Apr 24, 2023

Ryan Cavanaugh (RyanCavanaugh) marked this pull request as ready for review April 24, 2023 17:32

Bruce Pascoe (fatcerberus) mentioned this pull request Apr 25, 2023

Why the recursive function's return type inferenced as any? #53978

Closed

Andrew Branch (andrewbranch) mentioned this pull request Apr 26, 2023

Design Meeting Notes, 4/26/2023 #54038

Closed

Check for identifier operand and add testcase

674966b

Nathan Shively-Sanders (sandersn) requested review from Gabriela Araujo Britto (gabritto) and Ron Buckton (rbuckton) May 2, 2023 22:56

Jake Bailey (jakebailey) approved these changes May 5, 2023

View reviewed changes

Ryan Cavanaugh (RyanCavanaugh) merged commit e9cbebb into microsoft:main May 5, 2023

Ryan Cavanaugh (RyanCavanaugh) deleted the tailCalls branch May 5, 2023 17:59

Dan Rose (rotu) mentioned this pull request Aug 12, 2023

Infer type of simple recursion #55342

Closed

5 tasks

Ryan Cavanaugh (RyanCavanaugh) mentioned this pull request Oct 4, 2023

Recursive async function return type not inferred when await on the self call #55973

Closed

Mateusz Burzyński (Andarist) mentioned this pull request Oct 7, 2023

Ignore awaited self tail calls when collecting the return type of an async function #56020

Merged

Tony (hospotho) mentioned this pull request Apr 7, 2024

Inference of recursive arrow function's return type is any #58100

Closed

Microsoft (microsoft) locked as resolved and limited conversation to collaborators Oct 22, 2025

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debug

/mnt/ts_downloads/debug/tsconfig.json

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Compiler

TSServer

Startup

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