microsoft / microsoft/TypeScript
importModuleSpecifier "shortest" does not choose shortest result among multiple matching paths aliases
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Description
### 🔎 Search Terms
importModuleSpecifier shortest paths multiple aliases, auto import paths overlapping alias, tryGetModuleNameFromPaths shortest
### 🕗 Version & Regression Information
- This is the behavior in every version I tried, and I reviewed the FAQ for entries about auto-import and paths
### ⏯ Playground Link
N/A — this is a language service auto-import behavior that requires a multi-file project with jsconfig/tsconfig `paths`
### 💻 Code
```json
// jsconfig.json
{
"compilerOptions": {
"paths": {
"@@/*": ["./*"],
"@/*": ["./src/*"]
}
}
}
```
```js
// src/services/foo.js
export function foo() {}
// src/index.js — trigger auto-import for `foo`
```
### 🙁 Actual behavior
Auto-import suggests `@@/src/services/foo`. The `importModuleSpecifier: "shortest"` preference does not influence the choice between two matching `paths` aliases. `tryGetModuleNameFromPaths` returns on the first matching key in iteration order without comparing alternatives.
### 🙂 Expected behavior
With `importModuleSpecifier` set to `"shortest"`, auto-import should compare all matching aliases and suggest `@/services/foo` since it is shorter than `@@/src/services/foo`.
### Additional information about the issue
Workaround is to reorder `paths` entries so the more specific alias appears first, relying on object key insertion order. This is fragile and undocumented.
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start at the mentioned tryGetModuleNameFromPaths entry point and reproduce the multi-file auto-import case using the jsconfig/tsconfig paths configuration. Trace how matching aliases are selected, then verify that the shortest preference produces the shorter alias rather than depending on object key order.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- javascript, typescript
- Domain
- developer-experience, tooling
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Quiet
- Clarity
- Clearly specified
- Newbie friendliness
- 52/100