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Jul 5, 2024
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Update NoResolution.md #174

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phapdinh Jun 26, 2024
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6 changes: 3 additions & 3 deletions docs/problems/NoResolution.md
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Expand Up @@ -6,7 +6,7 @@ Import failed to resolve to type declarations or JavaScript files.

This problem indicates that TypeScript can’t find any file with a supported file extension (`.js`, `.mjs`, `.cjs`, `.jsx`, `.json`, `.ts`, `.mts`, `.cts`, `.tsx`) by following its own resolution algorithm, or a modified version of its resolution algorithm that ignores type declaration (`.d.ts`, `.d.mts`, `.d.cts`, `.d.*.ts`) files (which allows it to find JS files it would otherwise ignore).

## Consequnces
## Consequences

* Consumers will see TypeScript errors on imports/requires.
* If the diagnosis is accurate, a runtime/bundle-time error will occur.
Expand All @@ -15,7 +15,7 @@ This problem indicates that TypeScript can’t find any file with a supported fi

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☝️ There's another one -- "Consequnces" -- would you mind including that? I was just about to open a PR myself, but since you're already on it 😎

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good catch. thanks

### False positive: unsupported file extension

TypeScript doesn’t record non-JS/TS files as resolution results, and its API can’t be used to distinguish between a result with an unuspported file extension and a non-existent file. If a package.json subpath exposes a non-JS asset like a `.css` file, designed to be processed by a bundler or runtime extension, this will show up as a failed resolution, when it might be more accurately described as an [untyped resolution](./UntypedResolution.md) of an unknown file type.
TypeScript doesn’t record non-JS/TS files as resolution results, and its API can’t be used to distinguish between a result with an unsupported file extension and a non-existent file. If a package.json subpath exposes a non-JS asset like a `.css` file, designed to be processed by a bundler or runtime extension, this will show up as a failed resolution, when it might be more accurately described as an [untyped resolution](./UntypedResolution.md) of an unknown file type.

If the asset is intended to be imported as a side-effect import (`import "pkg/styles.css"`), this problem can safely be ignored.

Expand All @@ -36,4 +36,4 @@ When this problem occurs for the `node10` resolution option but not any others,

In this example, an import of `"pkg/subpath"` can be used in Node 12+ and modern bundlers, but would fail to resolve in Node 10. Accordingly, TypeScript’s `--moduleResolution node10` (also confusingly known as `node`, because history) does not resolve `"exports"` either.

While few libraries care about supporting a long-past EOL version of Node, maintainers of very popular libraries should be aware that many TypeScript users are still using `--moduleResolution node`. If they aren’t literally using Node 10, they really should move away from it, but sometimes migrating can be difficult because it introduces new errors caused by _incorrect dependency typings_—the problem this tool was made to diagnose. Popular libraries often choose to adopt a strategy that allows `--moduleResolution node10` to work even without `"exports"` support. https://github.com/andrewbranch/example-subpath-exports-ts-compat demonstrates several such strategies.
While few libraries care about supporting a long-past EOL version of Node, maintainers of very popular libraries should be aware that many TypeScript users are still using `--moduleResolution node`. If they aren’t literally using Node 10, they really should move away from it, but sometimes migrating can be difficult because it introduces new errors caused by _incorrect dependency typings_—the problem this tool was made to diagnose. Popular libraries often choose to adopt a strategy that allows `--moduleResolution node10` to work even without `"exports"` support. https://github.com/andrewbranch/example-subpath-exports-ts-compat demonstrates several such strategies.