transfer-out: transfer out

scripts/lib/add-extensions.ts

@@ -0,0 +1,68 @@
+import { existsSync, readFileSync, statSync, writeFileSync } from 'fs'
+import glob from 'glob'
+import path from 'path'
+import { parse, print, visit } from 'recast'
+
+const extensions = ['.js', '.mjs', '.cjs']
+function resolveRelativePath(importingFile: string, relativePath: string) {
+	if (!relativePath.startsWith('.')) {
+		return relativePath
+	}
+
+	const containingDir = path.dirname(importingFile)
+
+	if (
+		existsSync(path.join(containingDir, relativePath)) &&
+		!statSync(path.join(containingDir, relativePath)).isDirectory()
+	) {
+		// if the file already exists, e.g. .css files, just use it
+		return relativePath
+	}
+
+	// strip the file extension if applicable
+	relativePath.replace(/\.(m|c)?js$/, '')
+
+	for (const extension of extensions) {
+		if (relativePath.endsWith(extension)) {
+			return relativePath
+		} else {
+			let candidate = `${relativePath}${extension}`
+			if (existsSync(path.join(containingDir, candidate))) {
+				return candidate
+			}
+
+			candidate = `${relativePath}/index${extension}`
+
+			if (existsSync(path.join(containingDir, candidate))) {
+				return candidate
+			}
+		}
+	}
+
+	throw new Error(`Could not resolve relative path ${relativePath} from ${importingFile}`)
+}
+
+export function addJsExtensions(distDir: string) {
+	for (const file of glob.sync(path.join(distDir, '**/*.{mjs,cjs,js}'))) {
+		const code = parse(readFileSync(file, 'utf8'), { parser: require('recast/parsers/typescript') })
+
+		visit(code, {
+			visitImportDeclaration(path) {
+				path.value.source.value = resolveRelativePath(file, path.value.source.value)
+				return false
+			},
+			visitExportAllDeclaration(path) {
+				path.value.source.value = resolveRelativePath(file, path.value.source.value)
+				return false
+			},
+			visitExportNamedDeclaration(path) {
+				if (path.value.source) {
+					path.value.source.value = resolveRelativePath(file, path.value.source.value)
+				}
+				return false
+			},
+		})
+
+		writeFileSync(file, print(code).code)
+	}
+}