Function GetEachFileNameOfModule

internal/modulespecifiers/specifiers.go:260–357

GetEachFileNameOfModule returns all possible file paths for a module, including symlink alternatives. This function handles symlink resolution and provides multiple path options for module resolution.

(
	importingFileName string,
	importedFileName string,
	host ModuleSpecifierGenerationHost,
	preferSymlinks bool,
)

// GetEachFileNameOfModule returns all possible file paths for a module, including symlink alternatives.
// This function handles symlink resolution and provides multiple path options for module resolution.
func GetEachFileNameOfModule(
	importingFileName string,
	importedFileName string,
	host ModuleSpecifierGenerationHost,
	preferSymlinks bool,
) []ModulePath {
	cwd := host.GetCurrentDirectory()
	importedPath := tspath.ToPath(importedFileName, cwd, host.UseCaseSensitiveFileNames())
	var referenceRedirect string
	outputAndReference := host.GetProjectReferenceFromSource(importedPath)
	if outputAndReference != nil && outputAndReference.OutputDts != "" {
		referenceRedirect = outputAndReference.OutputDts
	}

	redirects := host.GetRedirectTargets(importedPath)
	importedFileNames := make([]string, 0, 2+len(redirects))
	if len(referenceRedirect) > 0 {
		importedFileNames = append(importedFileNames, referenceRedirect)
	}
	importedFileNames = append(importedFileNames, importedFileName)
	importedFileNames = append(importedFileNames, redirects...)
	targets := core.Map(importedFileNames, func(f string) string { return tspath.GetNormalizedAbsolutePath(f, cwd) })
	shouldFilterIgnoredPaths := !core.Every(targets, containsIgnoredPath)

	results := make([]ModulePath, 0, 2)
	if !preferSymlinks {
		for _, p := range targets {
			if !(shouldFilterIgnoredPaths && containsIgnoredPath(p)) {
				results = append(results, ModulePath{
					FileName:        p,
					IsInNodeModules: ContainsNodeModules(p),
					IsRedirect:      referenceRedirect == p,
				})
			}
		}
	}

	symlinkCache := host.GetSymlinkCache()
	fullImportedFileName := tspath.GetNormalizedAbsolutePath(importedFileName, cwd)
	if symlinkCache != nil {
		tspath.ForEachAncestorDirectoryStoppingAtGlobalCache(
			host.GetGlobalTypingsCacheLocation(),
			tspath.GetDirectoryPath(fullImportedFileName),
			func(realPathDirectory string) (bool, bool) {
				symlinkSet, ok := symlinkCache.DirectoriesByRealpath().Load(tspath.ToPath(realPathDirectory, cwd, host.UseCaseSensitiveFileNames()).EnsureTrailingDirectorySeparator())
				if !ok {
					return false, false
				} // Continue to ancestor directory

				// Don't want to a package to globally import from itself (importNameCodeFix_symlink_own_package.ts)
				if tspath.StartsWithDirectory(importingFileName, realPathDirectory, host.UseCaseSensitiveFileNames()) {
					return false, true // Stop search, each ancestor directory will also hit this condition
				}

				for _, target := range targets {
					if !tspath.StartsWithDirectory(target, realPathDirectory, host.UseCaseSensitiveFileNames()) {
						continue
					}