feat: file matcher (#41)

README.md

@@ -97,6 +97,47 @@ console.log(parseTsconfig('./path/to/tsconfig.custom.json'))
 
 ---
 
+### createFileMatcher(tsconfig: TsconfigResult, caseSensitivePaths?: boolean)
+
+Given a `tsconfig.json` file, it returns a file-matcher function that determines whether it should apply to a file path.
+
+```ts
+type FileMatcher = (filePath: string) => TsconfigResult['config'] | undefined
+```
+
+#### tsconfig
+Type: `TsconfigResult`
+
+Pass in the return value from `getTsconfig`, or a `TsconfigResult` object.
+
+#### caseSensitivePaths
+Type: `boolean`
+
+By default, it uses [`is-fs-case-sensitive`](https://github.com/privatenumber/is-fs-case-sensitive) to detect whether the file-system is case-sensitive.
+
+Pass in `true` to make it case-sensitive.
+
+#### Example
+
+For example, if it's called with a `tsconfig.json` file that has `include`/`exclude`/`files` defined, the file-matcher will return the config for files that match `include`/`files`, and return `undefined` for files that don't match or match `exclude`.
+
+```ts
+const tsconfig = getTsconfig()
+const fileMatcher = tsconfig && createFileMatcher(tsconfig)
+
+/*
+ * Returns tsconfig.json if it matches the file,
+ * undefined if not
+ */
+const configForFile = fileMatcher?.('/path/to/file.ts')
+const distCode = compileTypescript({
+    code: sourceCode,
+    tsconfig: configForFile
+})
+```
+
+---
+
 ### createPathsMatcher(tsconfig: TsconfigResult)
 
 Given a tsconfig with [`compilerOptions.paths`](https://www.typescriptlang.org/tsconfig#paths) defined, it returns a matcher function.

package.json

@@ -56,6 +56,7 @@
 		"eslint": "^8.30.0",
 		"execa": "^6.1.0",
 		"fs-fixture": "^1.2.0",
+		"is-fs-case-sensitive": "^1.0.0",
 		"jsonc-parser": "^3.2.0",
 		"manten": "^0.6.0",
 		"pkgroll": "^1.8.0",

src/files-matcher.ts

@@ -0,0 +1,221 @@
+import path from 'path';
+import slash from 'slash';
+import type { TsConfigJson } from 'type-fest';
+import { isFsCaseSensitive } from 'is-fs-case-sensitive';
+import type { TsConfigResult, TsConfigJsonResolved } from './types.js';
+
+export type FileMatcher = (filePath: string) => (TsConfigJsonResolved | undefined);
+
+const { join: pathJoin } = path.posix;
+
+const baseExtensions = {
+	ts: ['.ts', '.tsx', '.d.ts'],
+	cts: ['.cts', '.d.cts'],
+	mts: ['.mts', '.d.mts'],
+};
+
+const getSupportedExtensions = (
+	compilerOptions: TsConfigJson['compilerOptions'],
+) => {
+	const ts = [...baseExtensions.ts];
+	const cts = [...baseExtensions.cts];
+	const mts = [...baseExtensions.mts];
+
+	if (compilerOptions?.allowJs) {
+		ts.push('.js', '.jsx');
+		cts.push('.cjs');
+		mts.push('.mjs');
+	}
+
+	return [
+		...ts,
+		...cts,
+		...mts,
+	];
+};
+
+// https://github.com/microsoft/TypeScript/blob/acf854b636e0b8e5a12c3f9951d4edfa0fa73bcd/src/compiler/commandLineParser.ts#L3014-L3016
+const getDefaultExcludeSpec = (
+	compilerOptions: TsConfigJson['compilerOptions'],
+) => {
+	const excludesSpec: string[] = [];
+
+	if (!compilerOptions) {
+		return excludesSpec;
+	}
+
+	const { outDir, declarationDir } = compilerOptions;
+	if (outDir) {
+		excludesSpec.push(outDir);
+	}
+
+	if (declarationDir) {
+		excludesSpec.push(declarationDir);
+	}
+
+	return excludesSpec;
+};
+
+const escapeForRegexp = (string: string) => string.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
+
+const dependencyDirectories = ['node_modules', 'bower_components', 'jspm_packages'] as const;
+const implicitExcludePathRegexPattern = `(?!(${dependencyDirectories.join('|')})(/|$))`;
+
+/**
+ *
+ * File matchers
+ * replace *, ?, and ** / with regex
+ * https://github.com/microsoft/TypeScript/blob/acf854b636e0b8e5a12c3f9951d4edfa0fa73bcd/src/compiler/utilities.ts#L8088
+ *
+ * getSubPatternFromSpec
+ * https://github.com/microsoft/TypeScript/blob/acf854b636e0b8e5a12c3f9951d4edfa0fa73bcd/src/compiler/utilities.ts#L8165
+ *
+ * matchFiles
+ * https://github.com/microsoft/TypeScript/blob/acf854b636e0b8e5a12c3f9951d4edfa0fa73bcd/src/compiler/utilities.ts#L8291
+ *
+ * getFileMatcherPatterns
+ * https://github.com/microsoft/TypeScript/blob/acf854b636e0b8e5a12c3f9951d4edfa0fa73bcd/src/compiler/utilities.ts#L8267
+ */
+
+/**
+ * An "includes" path "foo" is implicitly a glob "foo/** /*" (without the space)
+ * if its last component has no extension, and does not contain any glob characters itself.
+ */
+const isImplicitGlobPattern = /(?:^|\/)[^.*?]+$/;
+
+const matchAllGlob = '**/*';
+
+const anyCharacter = '[^/]';
+
+const noPeriodOrSlash = '[^./]';
+
+const isWindows = process.platform === 'win32';
+
+export const createFilesMatcher = (
+	{
+		config,
+		path: tsconfigPath,
+	}: TsConfigResult,
+	caseSensitivePaths = isFsCaseSensitive(),
+): FileMatcher => {
+	if ('extends' in config) {
+		throw new Error('tsconfig#extends must be resolved. Use getTsconfig or parseTsconfig to resolve it.');
+	}
+
+	if (!path.isAbsolute(tsconfigPath)) {
+		throw new Error('The tsconfig path must be absolute');
+	}
+
+	if (isWindows) {
+		tsconfigPath = slash(tsconfigPath);
+	}
+
+	const projectDirectory = path.dirname(tsconfigPath);
+	const {
+		files, include, exclude, compilerOptions,
+	} = config;
+	const filesList = files?.map(file => pathJoin(projectDirectory, file));
+	const extensions = getSupportedExtensions(compilerOptions);
+	const regexpFlags = caseSensitivePaths ? '' : 'i';
+
+	/**
+	 * Match entire directory for `exclude`
+	 * https://github.com/microsoft/TypeScript/blob/acf854b636e0b8e5a12c3f9951d4edfa0fa73bcd/src/compiler/utilities.ts#L8135
+	 */
+	const excludeSpec = exclude || getDefaultExcludeSpec(compilerOptions);
+	const excludePatterns = excludeSpec
+		.map((filePath) => {
+			const projectFilePath = pathJoin(projectDirectory, filePath);
+			const projectFilePathPattern = escapeForRegexp(projectFilePath)
+
+				// Replace **/
+				.replace(/\\\*\\\*\//g, '(.+/)?')
+
+				// Replace *
+				.replace(/\\\*/g, `${anyCharacter}*`)
+
+				// Replace ?
+				.replace(/\\\?/g, anyCharacter);
+
+			return new RegExp(
+				`^${projectFilePathPattern}($|/)`,
+				regexpFlags,
+			);
+		});
+
+	// https://github.com/microsoft/TypeScript/blob/acf854b636e0b8e5a12c3f9951d4edfa0fa73bcd/src/compiler/commandLineParser.ts#LL3020C29-L3020C47
+	const includeSpec = !(files || include) ? [matchAllGlob] : include;
+	const includePatterns = includeSpec
+		? includeSpec.map((filePath) => {
+			let projectFilePath = pathJoin(projectDirectory, filePath);
+
+			// https://github.com/microsoft/TypeScript/blob/acf854b636e0b8e5a12c3f9951d4edfa0fa73bcd/src/compiler/utilities.ts#L8178
+			if (isImplicitGlobPattern.test(projectFilePath)) {
+				projectFilePath = pathJoin(projectFilePath, matchAllGlob);
+			}
+
+			const projectFilePathPattern = escapeForRegexp(projectFilePath)
+
+				// Replace /**
+				.replace(/\/\\\*\\\*/g, `(/${implicitExcludePathRegexPattern}${noPeriodOrSlash}${anyCharacter}*)*?`)
+
+				// Replace *
+				.replace(/(\/)?\\\*/g, (_, hasSlash) => {
+					const pattern = `(${noPeriodOrSlash}|(\\.(?!min\\.js$))?)*`;
+					if (hasSlash) {
+						return `/${implicitExcludePathRegexPattern}${noPeriodOrSlash}${pattern}`;
+					}
+
+					return pattern;
+				})
+
+				// Replace ?
+				.replace(/(\/)?\\\?/g, (_, hasSlash) => {
+					const pattern = anyCharacter;
+					if (hasSlash) {
+						return `/${implicitExcludePathRegexPattern}${pattern}`;
+					}
+
+					return pattern;
+				});
+
+			return new RegExp(
+				`^${projectFilePathPattern}$`,
+				regexpFlags,
+			);
+		})
+		: undefined;
+
+	return (
+		filePath: string,
+	) => {
+		if (!path.isAbsolute(filePath)) {
+			throw new Error('filePath must be absolute');
+		}
+
+		if (isWindows) {
+			filePath = slash(filePath);
+		}
+
+		if (filesList?.includes(filePath)) {
+			return config;
+		}
+
+		if (
+			// Invalid extension (case sensitive)
+			!extensions.some(extension => filePath.endsWith(extension))
+
+			// Matches exclude
+			|| excludePatterns.some(pattern => pattern.test(filePath))
+		) {
+			return;
+		}
+
+		if (
+			includePatterns
+			&& includePatterns.some(pattern => pattern.test(filePath))
+		) {
+			return config;
+		}
+	};
+};

src/index.ts

@@ -2,3 +2,4 @@ export * from './types.js';
 export * from './get-tsconfig.js';
 export * from './parse-tsconfig/index.js';
 export * from './paths-matcher/index.js';
+export * from './files-matcher.js';

tests/index.ts

@@ -4,4 +4,5 @@ describe('get-tsconfig', ({ runTestSuite }) => {
 	runTestSuite(import('./specs/get-tsconfig.js'));
 	runTestSuite(import('./specs/parse-tsconfig/index.js'));
 	runTestSuite(import('./specs/create-paths-matcher.js'));
+	runTestSuite(import('./specs/create-files-matcher.js'));
 });