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Default target to "latest standard", deprecate ES5 #63067

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@jakebailey jakebailey commented Jan 30, 2026 •
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target now defaults to ScriptTarget.LatestStandard, which is an alias to the most recent standardized ES version, currently ES2024 (until we add ES2025).

target=ES5 is now deprecated.

#63066 got most test ready, but a few unit tests still needed to be updated. Individual commits may be a better way to review this.

Fixes #62196
Fixes #62198

Copilot AI review requested due to automatic review settings January 30, 2026 03:37
@github-project-automation github-project-automation bot moved this to Not started in PR Backlog Jan 30, 2026
@typescript-bot typescript-bot added Author: Team For Milestone Bug PRs that fix a bug with a specific milestone labels Jan 30, 2026
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typescript-bot commented Jan 30, 2026

Thanks for the PR! It looks like you've changed the TSServer protocol in some way. Please ensure that any changes here don't break consumers of the current TSServer API. For some extra review, we'll ping @sheetalkamat, @mjbvz, and @joj for you. Feel free to loop in other consumers/maintainers if necessary.

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typescript-bot commented Jan 30, 2026

Looks like you're introducing a change to the public API surface area. If this includes breaking changes, please document them on our wiki's API Breaking Changes page.

Also, please make sure @DanielRosenwasser and @RyanCavanaugh are aware of the changes, just as a heads up.

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jakebailey commented Jan 30, 2026

@typescript-bot test it
@typescript-bot pack this

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typescript-bot commented Jan 30, 2026 •
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Starting jobs; this comment will be updated as builds start and complete.

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

jakebailey
jakebailey commented Jan 30, 2026
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typescript-bot commented Jan 30, 2026 •
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Hey @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/167004/artifacts?artifactName=tgz&fileId=EF769C50B14300245DEC1C19259502941AC541B769FEE5839095048E28F6936902&fileName=/typescript-6.0.0-insiders.20260130.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@6.0.0-pr-63067-4".;

jakebailey
jakebailey commented Jan 30, 2026
View reviewed changes
src/compiler/utilities.ts
computeValue: (compilerOptions): ModuleKind => {
return typeof compilerOptions.module === "number" ?
compilerOptions.module :
_computedOptions.target.computeValue(compilerOptions) >= ScriptTarget.ES2015 ? ModuleKind.ES2015 : ModuleKind.CommonJS;
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In a later PR, I will update this to set other ModuleKinds based on the target.

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typescript-bot commented Jan 30, 2026

@jakebailey Here are the results of running the user tests with tsc comparing main and refs/pull/63067/merge:

There were infrastructure failures potentially unrelated to your change:

  • 1 instance of "Package install failed"
  • 1 instance of "Git clone failed"

Otherwise...

Something interesting changed - please have a look.

Details

acorn

/mnt/ts_downloads/_/m/acorn/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/acorn/index.ts(1,1)

adonis-framework

/mnt/ts_downloads/_/m/adonis-framework/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/adonis-framework/index.ts(1,1)

ajv

/mnt/ts_downloads/_/m/ajv/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/ajv/index.ts(1,1)

antd

/mnt/ts_downloads/_/m/antd/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/antd/index.ts(1,1)

assert

/mnt/ts_downloads/_/m/assert/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/assert/index.ts(1,1)

async

/mnt/ts_downloads/_/m/async/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/async/index.ts(1,1)

axios

/mnt/ts_downloads/_/m/axios/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/axios/index.ts(1,1)

bcryptjs

/mnt/ts_downloads/_/m/bcryptjs/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/bcryptjs/index.ts(1,1)

bignumber.js

/mnt/ts_downloads/_/m/bignumber.js/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/bignumber.js/index.ts(1,1)

bluebird

/mnt/ts_downloads/_/m/bluebird/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/bluebird/index.ts(1,1)

clear-require

/mnt/ts_downloads/_/m/clear-require/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/clear-require/index.ts(1,1)

clone

/mnt/ts_downloads/_/m/clone/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/clone/index.ts(1,1)

content-disposition

/mnt/ts_downloads/_/m/content-disposition/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/content-disposition/index.ts(1,1)

debug

/mnt/ts_downloads/_/m/debug/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/debug/index.ts(1,1)

discord.js

/mnt/ts_downloads/_/m/discord.js/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/discord.js/index.ts(1,1)

electron

/mnt/ts_downloads/_/m/electron/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/electron/index.ts(1,1)

eventemitter2

/mnt/ts_downloads/_/m/eventemitter2/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/eventemitter2/index.ts(1,1)

eventemitter3

/mnt/ts_downloads/_/m/eventemitter3/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/eventemitter3/index.ts(1,1)

firebase

/mnt/ts_downloads/_/m/firebase/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/firebase/index.ts(1,1)

follow-redirects

/mnt/ts_downloads/_/m/follow-redirects/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/follow-redirects/index.ts(1,1)

fp-ts

tsconfig.json

  • [NEW] error TS5107: Option 'target=ES5' is deprecated and will stop functioning in TypeScript 7.0. Specify compilerOption '"ignoreDeprecations": "6.0"' to silence this error.

tsconfig.build-es6.json

  • [NEW] error TS5107: Option 'target=ES5' is deprecated and will stop functioning in TypeScript 7.0. Specify compilerOption '"ignoreDeprecations": "6.0"' to silence this error.

examples/tsconfig.json

  • [NEW] error TS5107: Option 'target=ES5' is deprecated and will stop functioning in TypeScript 7.0. Specify compilerOption '"ignoreDeprecations": "6.0"' to silence this error.

dtslint/tsconfig.json

  • [NEW] error TS5107: Option 'target=ES5' is deprecated and will stop functioning in TypeScript 7.0. Specify compilerOption '"ignoreDeprecations": "6.0"' to silence this error.

graceful-fs

/mnt/ts_downloads/_/m/graceful-fs/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/graceful-fs/index.ts(1,1)

immutable

/mnt/ts_downloads/_/m/immutable/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/immutable/index.ts(1,1)

isobject

/mnt/ts_downloads/_/m/isobject/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/isobject/index.ts(1,1)

jimp

/mnt/ts_downloads/_/m/jimp/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/jimp/index.ts(1,1)

jsonschema

/mnt/ts_downloads/_/m/jsonschema/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/jsonschema/index.ts(1,1)

keycode

/mnt/ts_downloads/_/m/keycode/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/keycode/index.ts(1,1)

localforage

/mnt/ts_downloads/_/m/localforage/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/localforage/index.ts(1,1)

lodash

/mnt/ts_downloads/_/m/lodash/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/lodash/index.ts(1,1)

log4js

/mnt/ts_downloads/_/m/log4js/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/log4js/index.ts(1,1)

minimatch

/mnt/ts_downloads/_/m/minimatch/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/minimatch/index.ts(1,1)

mobx

/mnt/ts_downloads/_/m/mobx/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/mobx/index.ts(1,1)

moment

/mnt/ts_downloads/_/m/moment/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/moment/index.ts(1,1)

mqtt

/mnt/ts_downloads/_/m/mqtt/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/mqtt/index.ts(1,1)

npmlog

/mnt/ts_downloads/_/m/npmlog/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/npmlog/index.ts(1,1)

octokit-rest

/mnt/ts_downloads/_/m/octokit-rest/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/octokit-rest/index.ts(1,1)

portfinder

/mnt/ts_downloads/_/m/portfinder/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/portfinder/index.ts(1,1)

protobufjs

/mnt/ts_downloads/_/m/protobufjs/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/protobufjs/index.ts(1,1)

redux

/mnt/ts_downloads/_/m/redux/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/redux/index.ts(1,1)

reselect

/mnt/ts_downloads/_/m/reselect/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/reselect/index.ts(1,1)

rxjs

/mnt/ts_downloads/_/m/rxjs/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/rxjs/index.ts(1,1)

should

/mnt/ts_downloads/_/m/should/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/should/index.ts(1,1)

sift

/mnt/ts_downloads/_/m/sift/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/sift/index.ts(1,1)

soap

/mnt/ts_downloads/_/m/soap/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/soap/index.ts(1,1)

sugar

/mnt/ts_downloads/_/m/sugar/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/sugar/index.ts(1,1)

tslint

/mnt/ts_downloads/_/m/tslint/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/tslint/index.ts(1,1)

uglify-js

/mnt/ts_downloads/_/m/uglify-js/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/uglify-js/index.ts(1,1)

url-search-params

/mnt/ts_downloads/_/m/url-search-params/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/url-search-params/index.ts(1,1)

util

/mnt/ts_downloads/_/m/util/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/util/index.ts(1,1)

vue

/mnt/ts_downloads/_/m/vue/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/vue/index.ts(1,1)

vuex

/mnt/ts_downloads/_/m/vuex/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/vuex/index.ts(1,1)

webpack

tsconfig.hot.json

  • [NEW] error TS5107: Option 'target=ES5' is deprecated and will stop functioning in TypeScript 7.0. Specify compilerOption '"ignoreDeprecations": "6.0"' to silence this error.

xlsx

/mnt/ts_downloads/_/m/xlsx/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/xlsx/index.ts(1,1)

xpath

/mnt/ts_downloads/_/m/xpath/tsconfig.json

  • [NEW] error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.
    • /mnt/ts_downloads/_/m/xpath/index.ts(1,1)

@jakebailey jakebailey mentioned this pull request Jan 30, 2026
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jakebailey commented Jan 30, 2026

@typescript-bot run dt

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typescript-bot commented Jan 30, 2026 •
edited
Loading

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

Command Status Results
run dt ✅ Started 👀 Results

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typescript-bot commented Jan 30, 2026

@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 2 3 🔻+1 (+50.00%) ~ ~ p=0.001 n=6
Symbols 62,370 62,370 ~ ~ ~ p=1.000 n=6
Types 50,387 50,387 ~ ~ ~ p=1.000 n=6
Memory used 194,565k (± 1.02%) 193,205k (± 0.75%) ~ 192,549k 196,174k p=0.128 n=6
Parse Time 1.31s (± 0.31%) 1.30s (± 0.42%) ~ 1.30s 1.31s p=0.282 n=6
Bind Time 0.76s 0.76s ~ ~ ~ p=1.000 n=6
Check Time 9.88s (± 0.19%) 9.87s (± 0.32%) ~ 9.83s 9.92s p=0.809 n=6
Emit Time 2.75s (± 0.56%) 2.74s (± 1.12%) ~ 2.70s 2.78s p=0.745 n=6
Total Time 14.70s (± 0.22%) 14.67s (± 0.25%) ~ 14.66s 14.75s p=0.277 n=6
angular-1 - node (v18.15.0, x64)
Errors 2 2 ~ ~ ~ p=1.000 n=6
Symbols 955,823 955,823 ~ ~ ~ p=1.000 n=6
Types 415,853 415,853 ~ ~ ~ p=1.000 n=6
Memory used 1,253,927k (± 0.00%) 1,253,938k (± 0.01%) ~ 1,253,840k 1,254,023k p=0.689 n=6
Parse Time 6.52s (± 0.59%) 6.51s (± 0.42%) ~ 6.48s 6.56s p=0.572 n=6
Bind Time 1.96s (± 0.26%) 1.96s (± 0.32%) ~ 1.95s 1.97s p=0.386 n=6
Check Time 32.42s (± 0.23%) 32.40s (± 0.34%) ~ 32.23s 32.53s p=0.873 n=6
Emit Time 15.01s (± 0.47%) 15.00s (± 0.34%) ~ 14.96s 15.08s p=1.000 n=6
Total Time 55.91s (± 0.19%) 55.87s (± 0.28%) ~ 55.65s 56.09s p=0.575 n=6
mui-docs - node (v18.15.0, x64)
Errors 11,439 11,439 ~ ~ ~ p=1.000 n=6
Symbols 2,701,678 2,701,678 ~ ~ ~ p=1.000 n=6
Types 930,572 930,572 ~ ~ ~ p=1.000 n=6
Memory used 3,037,101k (± 0.01%) 3,037,053k (± 0.00%) ~ 3,036,863k 3,037,152k p=0.810 n=6
Parse Time 10.27s (± 0.48%) 10.25s (± 0.39%) ~ 10.22s 10.33s p=0.421 n=6
Bind Time 2.76s (± 0.70%) 2.76s (± 0.77%) ~ 2.74s 2.80s p=1.000 n=6
Check Time 110.46s (± 0.57%) 111.67s (± 2.71%) ~ 109.89s 117.68s p=0.810 n=6
Emit Time 0.74s (±118.58%) 0.39s (± 2.67%) ~ 0.37s 0.40s p=1.000 n=6
Total Time 124.23s (± 0.86%) 125.07s (± 2.41%) ~ 123.25s 131.05s p=0.936 n=6
self-build-src - node (v18.15.0, x64)
Errors 0 0 ~ ~ ~ p=1.000 n=6
Symbols 1,252,499 1,252,473 -26 (- 0.00%) ~ ~ p=0.001 n=6
Types 259,939 259,933 -6 (- 0.00%) ~ ~ p=0.001 n=6
Memory used 2,570,512k (±11.85%) 2,387,841k (± 0.03%) ~ 2,387,238k 2,388,965k p=0.093 n=6
Parse Time 5.19s (± 1.30%) 5.15s (± 0.85%) ~ 5.06s 5.18s p=0.228 n=6
Bind Time 1.86s (± 0.96%) 1.86s (± 0.48%) ~ 1.85s 1.87s p=0.804 n=6
Check Time 35.52s (± 1.11%) 35.53s (± 0.54%) ~ 35.35s 35.88s p=0.810 n=6
Emit Time 3.03s (± 2.50%) 3.02s (± 1.87%) ~ 2.95s 3.09s p=0.689 n=6
Total Time 45.61s (± 0.92%) 45.58s (± 0.52%) ~ 45.33s 46.00s p=0.689 n=6
self-build-src-public-api - node (v18.15.0, x64)
Errors 0 0 ~ ~ ~ p=1.000 n=6
Symbols 1,252,499 1,252,473 -26 (- 0.00%) ~ ~ p=0.001 n=6
Types 259,939 259,933 -6 (- 0.00%) ~ ~ p=0.001 n=6
Memory used 3,061,873k (± 9.68%) 3,183,665k (± 0.03%) ~ 3,182,592k 3,184,650k p=0.173 n=6
Parse Time 6.79s (± 0.93%) 6.76s (± 1.43%) ~ 6.62s 6.91s p=0.688 n=6
Bind Time 2.27s (± 1.27%) 2.24s (± 0.83%) ~ 2.22s 2.27s p=0.335 n=6
Check Time 43.06s (± 0.41%) 43.03s (± 0.34%) ~ 42.75s 43.19s p=0.810 n=6
Emit Time 3.52s (± 2.99%) 3.47s (± 2.42%) ~ 3.39s 3.59s p=0.521 n=6
Total Time 55.65s (± 0.34%) 55.51s (± 0.41%) ~ 55.15s 55.83s p=0.336 n=6
self-compiler - node (v18.15.0, x64)
Errors 0 0 ~ ~ ~ p=1.000 n=6
Symbols 264,692 264,628 -64 (- 0.02%) ~ ~ p=0.001 n=6
Types 104,082 104,073 -9 (- 0.01%) ~ ~ p=0.001 n=6
Memory used 442,791k (± 0.01%) 442,751k (± 0.01%) ~ 442,725k 442,795k p=0.128 n=6
Parse Time 2.84s (± 0.98%) 2.85s (± 0.69%) ~ 2.83s 2.88s p=0.375 n=6
Bind Time 1.16s (± 0.54%) 1.16s (± 0.35%) ~ 1.15s 1.16s p=0.673 n=6
Check Time 16.01s (± 0.21%) 16.00s (± 0.32%) ~ 15.93s 16.06s p=1.000 n=6
Emit Time 1.31s (± 1.42%) 1.32s (± 1.14%) ~ 1.30s 1.34s p=0.413 n=6
Total Time 21.32s (± 0.21%) 21.33s (± 0.37%) ~ 21.21s 21.40s p=0.469 n=6
ts-pre-modules - node (v18.15.0, x64)
Errors 73 74 +1 (+ 1.37%) ~ ~ p=0.001 n=6
Symbols 225,493 225,493 ~ ~ ~ p=1.000 n=6
Types 94,373 94,373 ~ ~ ~ p=1.000 n=6
Memory used 369,973k (± 0.10%) 369,914k (± 0.07%) ~ 369,762k 370,403k p=0.810 n=6
Parse Time 2.81s (± 1.20%) 2.82s (± 1.17%) ~ 2.76s 2.85s p=0.809 n=6
Bind Time 1.66s (± 0.82%) 1.65s (± 1.07%) ~ 1.62s 1.66s p=0.405 n=6
Check Time 16.63s (± 0.30%) 16.66s (± 0.46%) ~ 16.60s 16.81s p=0.422 n=6
Emit Time 0.00s 0.00s (±244.70%) ~ 0.00s 0.01s p=0.405 n=6
Total Time 21.10s (± 0.40%) 21.13s (± 0.47%) ~ 21.03s 21.31s p=0.573 n=6
vscode - node (v18.15.0, x64)
Errors 11 11 ~ ~ ~ p=1.000 n=6
Symbols 4,186,623 4,186,623 ~ ~ ~ p=1.000 n=6
Types 1,326,648 1,326,648 ~ ~ ~ p=1.000 n=6
Memory used 3,979,520k (± 0.00%) 3,979,428k (± 0.00%) ~ 3,979,129k 3,979,612k p=0.575 n=6
Parse Time 16.13s (± 0.80%) 16.10s (± 0.52%) ~ 16.01s 16.18s p=0.688 n=6
Bind Time 5.43s (± 0.30%) 5.43s (± 0.34%) ~ 5.40s 5.45s p=1.000 n=6
Check Time 120.53s (± 5.28%) 122.13s (± 7.58%) ~ 113.82s 139.89s p=1.000 n=6
Emit Time 56.20s (±12.14%) 57.36s (±12.82%) ~ 48.13s 67.29s p=0.936 n=6
Total Time 198.29s (± 4.07%) 201.02s (± 4.87%) ~ 188.65s 214.52s p=1.000 n=6
webpack - node (v18.15.0, x64)
Errors 41 41 ~ ~ ~ p=1.000 n=6
Symbols 395,804 395,804 ~ ~ ~ p=1.000 n=6
Types 175,167 175,167 ~ ~ ~ p=1.000 n=6
Memory used 548,344k (± 0.01%) 548,283k (± 0.02%) ~ 548,162k 548,463k p=0.230 n=6
Parse Time 4.63s (± 0.18%) 4.62s (± 0.18%) ~ 4.61s 4.63s p=0.796 n=6
Bind Time 2.02s (± 0.99%) 2.00s (± 0.98%) ~ 1.97s 2.02s p=0.280 n=6
Check Time 24.09s (± 1.17%) 23.94s (± 1.26%) ~ 23.41s 24.20s p=0.261 n=6
Emit Time 0.01s (±48.94%) 0.00s (±244.70%) 🟩-0.01s (-80.00%) 0.00s 0.01s p=0.034 n=6
Total Time 30.74s (± 0.94%) 30.57s (± 1.04%) ~ 30.00s 30.83s p=0.092 n=6
xstate-main - node (v18.15.0, x64)
Errors 30 30 ~ ~ ~ p=1.000 n=6
Symbols 731,941 731,941 ~ ~ ~ p=1.000 n=6
Types 219,279 219,279 ~ ~ ~ p=1.000 n=6
Memory used 634,989k (± 0.01%) 635,060k (± 0.01%) ~ 634,949k 635,151k p=0.066 n=6
Parse Time 4.56s (± 0.86%) 4.59s (± 0.43%) ~ 4.56s 4.62s p=0.217 n=6
Bind Time 1.49s (± 0.51%) 1.49s (± 0.78%) ~ 1.47s 1.50s p=0.933 n=6
Check Time 22.14s (± 0.34%) 22.20s (± 0.39%) ~ 22.08s 22.28s p=0.260 n=6
Emit Time 0.00s 0.00s (±244.70%) ~ 0.00s 0.01s p=0.405 n=6
Total Time 28.19s (± 0.32%) 28.28s (± 0.32%) ~ 28.17s 28.40s p=0.173 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:

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typescript-bot commented Jan 30, 2026

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

There were interesting changes:

Branch only errors:

Package: activex-wia
Error:

Error: 
/mnt/vss/_work/1/DefinitelyTyped/types/activex-wia/activex-wia-tests.ts
   59:29  error  TypeScript@local compile error: 
Type 'Property[]' must have a '[Symbol.iterator]()' method that returns an iterator     @definitelytyped/expect
  122:29  error  TypeScript@local compile error: 
Type 'Property[]' must have a '[Symbol.iterator]()' method that returns an iterator     @definitelytyped/expect
  143:29  error  TypeScript@local compile error: 
Type 'DeviceEvent[]' must have a '[Symbol.iterator]()' method that returns an iterator  @definitelytyped/expect
  218:26  error  TypeScript@local compile error: 
Type 'FilterInfo[]' must have a '[Symbol.iterator]()' method that returns an iterator   @definitelytyped/expect
  283:26  error  TypeScript@local compile error: 
Type 'FilterInfo[]' must have a '[Symbol.iterator]()' method that returns an iterator   @definitelytyped/expect
  329:32  error  TypeScript@local compile error: 
Type 'Item[]' must have a '[Symbol.iterator]()' method that returns an iterator         @definitelytyped/expect
  362:22  error  TypeScript@local compile error: 
Type 'DeviceInfo[]' must have a '[Symbol.iterator]()' method that returns an iterator   @definitelytyped/expect
  371:29  error  TypeScript@local compile error: 
Type 'Property[]' must have a '[Symbol.iterator]()' method that returns an iterator     @definitelytyped/expect
  453:40  error  TypeScript@local compile error: 
Type 'Item[]' must have a '[Symbol.iterator]()' method that returns an iterator         @definitelytyped/expect

✖ 9 problems (9 errors, 0 warnings)

    at combineErrorsAndWarnings (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:199:28)
    at runTests (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:191:20)

Package: activex-vbide
Error:

Error: 
/mnt/vss/_work/1/DefinitelyTyped/types/activex-vbide/activex-vbide-tests.ts
  18:23  error  TypeScript@local compile error: 
Type 'VBProject[]' must have a '[Symbol.iterator]()' method that returns an iterator  @definitelytyped/expect
  21:29  error  TypeScript@local compile error: 
Type 'unknown[]' must have a '[Symbol.iterator]()' method that returns an iterator    @definitelytyped/expect

✖ 2 problems (2 errors, 0 warnings)

    at combineErrorsAndWarnings (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:199:28)
    at runTests (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:191:20)

Package: activex-excel
Error:

Error: 
/mnt/vss/_work/1/DefinitelyTyped/types/activex-excel/activex-excel-tests.ts
  303:25  error  TypeScript@local compile error: 
Type 'any[]' must have a '[Symbol.iterator]()' method that returns an iterator                @definitelytyped/expect
  340:30  error  TypeScript@local compile error: 
Type 'XlClipboardFormat[]' must have a '[Symbol.iterator]()' method that returns an iterator  @definitelytyped/expect

✖ 2 problems (2 errors, 0 warnings)

    at combineErrorsAndWarnings (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:199:28)
    at runTests (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:191:20)

Package: activex-adodb
Error:

Error: 
/mnt/vss/_work/1/DefinitelyTyped/types/activex-adodb/activex-adodb-tests.ts
  404:35  error  TypeScript@local compile error: 
Type 'Error[]' must have a '[Symbol.iterator]()' method that returns an iterator  @definitelytyped/expect

✖ 1 problem (1 error, 0 warnings)

    at combineErrorsAndWarnings (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:199:28)
    at runTests (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:191:20)

Package: windows-script-host
Error:

Error: 
/mnt/vss/_work/1/DefinitelyTyped/types/windows-script-host/windows-script-host-tests.ts
  15:19  error  TypeScript@local compile error: 
Type 'string[]' must have a '[Symbol.iterator]()' method that returns an iterator  @definitelytyped/expect
  22:23  error  TypeScript@local compile error: 
Type 'string[]' must have a '[Symbol.iterator]()' method that returns an iterator  @definitelytyped/expect
  28:19  error  TypeScript@local compile error: 
Type 'string[]' must have a '[Symbol.iterator]()' method that returns an iterator  @definitelytyped/expect

✖ 3 problems (3 errors, 0 warnings)

    at combineErrorsAndWarnings (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:199:28)
    at runTests (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:191:20)

Package: activex-office
Error:

Error: 
/mnt/vss/_work/1/DefinitelyTyped/types/activex-office/activex-office-tests.ts
  21:20  error  TypeScript@local compile error: 
Type 'string[]' must have a '[Symbol.iterator]()' method that returns an iterator    @definitelytyped/expect
  25:20  error  TypeScript@local compile error: 
Type 'COMAddIn[]' must have a '[Symbol.iterator]()' method that returns an iterator  @definitelytyped/expect

✖ 2 problems (2 errors, 0 warnings)

    at combineErrorsAndWarnings (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:199:28)
    at runTests (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:191:20)

Package: wallabyjs
Error:

Error: 
/mnt/vss/_work/1/DefinitelyTyped/types/wallabyjs/wallabyjs-tests.ts
  29:29  error  TypeScript@local compile error: 
Property 'wallaby' is used before its initialization  @definitelytyped/expect
  30:29  error  TypeScript@local compile error: 
Property 'wallaby' is used before its initialization  @definitelytyped/expect
  31:33  error  TypeScript@local compile error: 
Property 'wallaby' is used before its initialization  @definitelytyped/expect

✖ 3 problems (3 errors, 0 warnings)

    at combineErrorsAndWarnings (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:199:28)
    at runTests (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:191:20)

Package: react
Error:

Error: 
/mnt/vss/_work/1/DefinitelyTyped/types/react/test/index.ts
  138:5   error  TypeScript@local compile error: 
Property 'context' will overwrite the base property in 'Component<Props, State, Snapshot>'. If this is intentional, add an initializer. Otherwise, add a 'declare' modifier or remove the redundant declaration  @definitelytyped/expect
  145:26  error  TypeScript@local compile error: 
Property 'context' is used before its initialization                                                                                                                                                             @definitelytyped/expect

✖ 2 problems (2 errors, 0 warnings)

    at combineErrorsAndWarnings (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:199:28)
    at runTests (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:191:20)

Package: activex-adox
Error:

Error: 
/mnt/vss/_work/1/DefinitelyTyped/types/activex-adox/activex-adox-tests.ts
   138:27  error  TypeScript@local compile error: 
Type 'Table[]' must have a '[Symbol.iterator]()' method that returns an iterator           @definitelytyped/expect
   217:25  error  TypeScript@local compile error: 
Type 'User[]' must have a '[Symbol.iterator]()' method that returns an iterator            @definitelytyped/expect
   218:29  error  TypeScript@local compile error: 
'usrLoop' is possibly 'null'                                                               @definitelytyped/expect
   221:46  error  TypeScript@local compile error: 
'usrLoop' is possibly 'null'                                                               @definitelytyped/expect
   223:31  error  TypeScript@local compile error: 
Type 'Group[]' must have a '[Symbol.iterator]()' method that returns an iterator           @definitelytyped/expect
   224:41  error  TypeScript@local compile error: 
'group' is possibly 'null'                                                                 @definitelytyped/expect
   232:25  error  TypeScript@local compile error: 
Type 'Group[]' must have a '[Symbol.iterator]()' method that returns an iterator           @definitelytyped/expect
   233:29  error  TypeScript@local compile error: 
'grpLoop' is possibly 'null'                                                               @definitelytyped/expect
   236:45  error  TypeScript@local compile error: 
'grpLoop' is possibly 'null'                                                               @definitelytyped/expect
   238:30  error  TypeScript@local compile error: 
Type 'User[]' must have a '[Symbol.iterator]()' method that returns an iterator            @definitelytyped/expect
   239:41  error  TypeScript@local compile error: 
'user' is possibly 'null'                                                                  @definitelytyped/expect
   570:25  error  TypeScript@local compile error: 
Type 'Table[]' must have a '[Symbol.iterator]()' method that returns an iterator           @definitelytyped/expect
   572:29  error  TypeScript@local compile error: 
Type 'Index[]' must have a '[Symbol.iterator]()' method that returns an iterator           @definitelytyped/expect
   572:47  error  TypeScript@local compile error: 
'tblLoop' is possibly 'null'                                                               @definitelytyped/expect
   573:33  error  TypeScript@local compile error: 
'tblLoop' is possibly 'null'                                                               @definitelytyped/expect
   573:49  error  TypeScript@local compile error: 
'idxLoop' is possibly 'null'                                                               @definitelytyped/expect
   573:65  error  TypeScript@local compile error: 
'idxLoop' is possibly 'null'                                                               @definitelytyped/expect
   642:21  error  TypeScript@local compile error: 
Type 'Parameter[]' must have a '[Symbol.iterator]()' method that returns an iterator       @definitelytyped/expect
   643:29  error  TypeScript@local compile error: 
'prm' is possibly 'null'                                                                   @definitelytyped/expect
   643:42  error  TypeScript@local compile error: 
'prm' is possibly 'null'                                                                   @definitelytyped/expect
   760:19  error  TypeScript@local compile error: 
Type '[string, string]' must have a '[Symbol.iterator]()' method that returns an iterator  @definitelytyped/expect
   960:25  error  TypeScript@local compile error: 
Type 'Column[]' must have a '[Symbol.iterator]()' method that returns an iterator          @definitelytyped/expect
   961:17  error  TypeScript@local compile error: 
'colLoop' is possibly 'null'                                                               @definitelytyped/expect
   963:11  error  TypeScript@local compile error: 
'colLoop' is possibly 'null'                                                               @definitelytyped/expect
   964:18  error  TypeScript@local compile error: 
'colLoop' is possibly 'null'                                                               @definitelytyped/expect
   965:14  error  TypeScript@local compile error: 
'colLoop' is possibly 'null'                                                               @definitelytyped/expect
  1056:25  error  TypeScript@local compile error: 
Type 'Index[]' must have a '[Symbol.iterator]()' method that returns an iterator           @definitelytyped/expect
  1058:9   error  TypeScript@local compile error: 
'idxLoop' is possibly 'null'                                                               @definitelytyped/expect
  1059:21  error  TypeScript@local compile error: 
'idxLoop' is possibly 'null'                                                               @definitelytyped/expect
  1060:16  error  TypeScript@local compile error: 
'idxLoop' is possibly 'null'                                                               @definitelytyped/expect
  1061:35  error  TypeScript@local compile error: 
'idxLoop' is possibly 'null'                                                               @definitelytyped/expect
  1181:21  error  TypeScript@local compile error: 
Type 'Field[]' must have a '[Symbol.iterator]()' method that returns an iterator           @definitelytyped/expect
  1182:29  error  TypeScript@local compile error: 
'fld' is possibly 'null'                                                                   @definitelytyped/expect
  1182:41  error  TypeScript@local compile error: 
'fld' is possibly 'null'                                                                   @definitelytyped/expect
  1219:21  error  TypeScript@local compile error: 
Type 'TableIndex[]' must have a '[Symbol.iterator]()' method that returns an iterator      @definitelytyped/expect
  1220:69  error  TypeScript@local compile error: 
'col' is of type 'unknown'                                                                 @definitelytyped/expect

✖ 36 problems (36 errors, 0 warnings)

    at combineErrorsAndWarnings (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:199:28)
    at runTests (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:191:20)

Package: backbone
Error:

Error: 
/mnt/vss/_work/1/DefinitelyTyped/types/backbone/backbone-tests.ts
  228:5  error  TypeScript@local compile error: 
Property 'model' will overwrite the base property in 'Collection<Book>'. If this is intentional, add an initializer. Otherwise, add a 'declare' modifier or remove the redundant declaration  @definitelytyped/expect

✖ 1 problem (1 error, 0 warnings)

    at combineErrorsAndWarnings (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:199:28)
    at runTests (/mnt/vss/_work/1/DefinitelyTyped/node_modules/.pnpm/@definitelytyped+dtslint@0.2.34_typescript@6.0.0-dev.20260129/node_modules/@definitelytyped/dtslint/dist/index.js:191:20)

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typescript-bot commented Jan 30, 2026

@jakebailey Here are the results of running the top 400 repos with tsc comparing main and refs/pull/63067/merge:

Something interesting changed - please have a look.

Details

apitable/apitable

14 of 15 projects failed to build with the old tsc and were ignored

packages/databus-client/tsconfig.json

  • error TS5107: Option 'target=ES5' is deprecated and will stop functioning in TypeScript 7.0. Specify compilerOption '"ignoreDeprecations": "6.0"' to silence this error.

basarat/typescript-book

10 of 15 projects failed to build with the old tsc and were ignored

code/async-await/es5/tsconfig.json

  • error TS5107: Option 'target=ES5' is deprecated and will stop functioning in TypeScript 7.0. Specify compilerOption '"ignoreDeprecations": "6.0"' to silence this error.

compiler-explorer/compiler-explorer

4 of 7 projects failed to build with the old tsc and were ignored

tsconfig.frontend.tests.json

  • error TS5107: Option 'target=ES5' is deprecated and will stop functioning in TypeScript 7.0. Specify compilerOption '"ignoreDeprecations": "6.0"' to silence this error.
    • Project Scope

faker-js/faker

1 of 2 projects failed to build with the old tsc and were ignored

cypress/tsconfig.json

  • error TS5107: Option 'target=ES5' is deprecated and will stop functioning in TypeScript 7.0. Specify compilerOption '"ignoreDeprecations": "6.0"' to silence this error.

radix-ui/primitives

64 of 68 projects failed to build with the old tsc and were ignored

cypress/tsconfig.json

  • error TS5107: Option 'target=ES5' is deprecated and will stop functioning in TypeScript 7.0. Specify compilerOption '"ignoreDeprecations": "6.0"' to silence this error.

RyanCavanaugh
RyanCavanaugh requested changes Jan 30, 2026
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Overall LGTM, I am OK with any proposed name for the "current" target version

@github-project-automation github-project-automation bot moved this from Not started to Waiting on author in PR Backlog Jan 30, 2026
@jakebailey jakebailey mentioned this pull request Jan 30, 2026
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@jakebailey jakebailey changed the title Default target to "current year", deprecate ES5 Default target to "latest standard", deprecate ES5 Jan 30, 2026
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@RyanCavanaugh RyanCavanaugh RyanCavanaugh requested changes

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@Andarist Andarist Andarist left review comments

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Change default --target to latest ECMAScript version Deprecate --target es5, make lowest target es2015

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@jakebailey @typescript-bot @RyanCavanaugh @Andarist