Exposing canonical filename logic

Search Terms

canonical filename

Suggestion

I'd like to re-use the get-canonical-filename logic:
https://github.com/microsoft/TypeScript/blob/d68295e74e4897f588e73edf72089eb238904f02/src/compiler/core.ts#L1906-L1909

Use Cases

I want to use ts.resolveModuleName and the accompanying ts.createModuleResolutionCache to resolve ImportDeclarations (as per this comment's suggestion).
createModuleResolutionCache requires a parameter getCanonicalFileName. I think it makes the most sense to use the same logic as the compiler itself here, which is the function I linked above.

I could just copy-and-paste this function, but that feels wrong and might lead to discrepancies in the future if toFileNameLowerCase (which is not exposed either) is ever updated.

Examples

const cache = ts.createModuleResolutionCache(currentDirectory, ts.createGetCanonicalFileName(true/false));
const resolved = ts.resolveModuleName(name, file, compilerOptions, host, cache);

Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

src/compiler/core.ts の 1906-1909 行にある正規ファイル名のロジックから始め、createModuleResolutionCache のエントリポイントを調べてください。Issue で同じくリンクされている toFileNameLowerCase と比較し、例に必要な public helper の形を判断してください。モジュール解決のために、consumer がコンパイラーの正規ファイル名の動作をロジックをコピーせずに再利用できれば完了です。