TypeScript incorrectly auto-importing string from fp-ts.

[kkirby]

Bug Report

I originally commented on this issue: #35395 but was directed to make a new issue.

If I have fp-ts installed to my project, and then type something like:

type A = {
  value: string;
}

The TypeScript language server auto-imports string from fp-ts.

A minimum reproduction can be done on CodeSandbox. Simply create an empty TypeScript project. Add fp-ts to the dependencies. Then type the code above in the editor and you'll see that it wants to auto-import string from fp-ts:

If it doesn't pop up right away you might need to trigger the auto-complete by hitting ctrl-space on your keyboard.

Here's a pre-created CodeSandbox to test with: https://codesandbox.io/s/bitter-shape-3rnzh9?file=/src/index.ts

🔎 Search Terms

N/A

🕗 Version & Regression Information

Tested 4.4.5, 4.6.2

• This is the behavior in every version I tried

🙁 Actual behavior

TypeScript auto-imports string from fp-ts.

🙂 Expected behavior

TypeScript does not auto-imports string from fp-ts.

[tjjfvi]

Bug reports should follow the issue template for bug reports to help the TypeScript team triage and address the issue.

[willmanduffy]

Just to note, not only does this happen with string but it also happens with boolean and perhaps others.

[andrewbranch]

I 👍 this earlier so I assume I could repro it at the time, or maybe I just repro’d it in the Code Sanbdbox which is using TypeScript 4.5, but I can’t repro on nightly:

string from fp-ts is there in a value position:

@kkirby or @willmanduffy, can you confirm that this is fixed when you use typescript@next as your VS Code TS version?

[kkirby]

@andrewbranch Still broken for me when using typescript@next:

From the ts server log file:

Info 0    [10:57:25.632] Starting TS Server
Info 1    [10:57:25.633] Version: 4.7.0-dev.20220422
Info 2    [10:57:25.633] Arguments: /Applications/Visual Studio Code.app/Contents/MacOS/Electron /Users/kkirbatski/Projects/test/node_modules/typescript/lib/tsserver.js --useInferredProjectPerProjectRoot --enableTelemetry --cancellationPipeName /var/folders/vf/bdglby3n3r72_zfhj_b4zkw80000gn/T/vscode-typescript501/e779ed38cfeaa09de81a/tscancellation-9f6e3c1c4a583dfac398.tmp* --logVerbosity normal --logFile /Users/kkirbatski/Library/Application Support/Code/logs/20220422T105425/exthost1/vscode.typescript-language-features/tsserver-log-MdTheW/tsserver.log --globalPlugins typescript-svelte-plugin,@vsintellicode/typescript-intellicode-plugin --pluginProbeLocations /Users/kkirbatski/.vscode/extensions/svelte.svelte-vscode-105.16.0,/Users/kkirbatski/.vscode/extensions/visualstudioexptteam.vscodeintellicode-1.2.20 --locale en --noGetErrOnBackgroundUpdate --validateDefaultNpmLocation --useNodeIpc
Info 3    [10:57:25.633] Platform: darwin NodeVersion: 16 CaseSensitive: false
Info 4    [10:57:25.633] ServerMode: undefined syntaxOnly: false hasUnknownServerMode: undefined
Info 5    [10:57:25.642] Host information vscode
Info 6    [10:57:25.643] Host watch options changed to undefined, it will be take effect for next watches.
Info 7    [10:57:25.644] Search path: /Users/kkirbatski/Projects/test/src
Info 8    [10:57:25.645] For info: /Users/kkirbatski/Projects/test/src/Interface.ts :: Config file name: /Users/kkirbatski/Projects/test/tsconfig.json
Info 9    [10:57:25.645] Creating configuration project /Users/kkirbatski/Projects/test/tsconfig.json

[andrewbranch]

What the heck. @kkirby would you mind throwing that test project in a gist/repo/zip and sending it to me?

[kkirby]

@andrewbranch Sure, here: https://github.com/kkirby/typescript-issue-48075

I will point out that upon opening the project, I didn't initially get the issue to occur. I had to give it awhile. Maybe the TypeScript server was still caching stuff or whatever. Let me know how it goes. There's a file in the repo called "repo_steps.mp4" that shows the problem occurring in that project.

[andrewbranch]

Ah, ok—the thing I was doing to make it more likely to happen—importing from fp-ts elsewhere in the file or project—actually makes it not happen. This only occurs when you haven’t used fp-ts anywhere in your project yet 😱. Anyway, thanks for the repro, this should be easy to figure out now!