docgen: Optimize README update script

bin/api-docs/are-api-docs-unstaged.js

@@ -0,0 +1,43 @@
+#!/usr/bin/env node
+
+/**
+ * Node dependencies.
+ */
+const { extname } = require( 'path' );
+const chalk = require( 'chalk' );
+const execSync = require( 'child_process' ).execSync;
+const { readFile } = require( 'fs' ).promises;
+
+const getUnstagedFiles = () =>
+	execSync( 'git diff --name-only', { encoding: 'utf8' } )
+		.split( '\n' )
+		.filter( Boolean );
+
+const fileHasToken = async ( file ) =>
+	( await readFile( file, 'utf8' ) ).includes( '<!-- START TOKEN' );
+
+const getUnstagedReadmes = () =>
+	Promise.all(
+		getUnstagedFiles().map(
+			async ( file ) =>
+				extname( file ) === '.md' &&
+				( await fileHasToken( file ) ) &&
+				file
+		)
+	).then( ( files ) => files.filter( Boolean ) );
+
+( async () => {
+	const unstagedReadmes = await getUnstagedReadmes();
+	if ( unstagedReadmes.length > 0 ) {
+		process.exitCode = 1;
+		process.stdout.write(
+			chalk.red(
+				'\n',
+				'Some API docs may be out of date:',
+				unstagedReadmes.toString(),
+				'Either stage them or continue with --no-verify.',
+				'\n'
+			)
+		);
+	}
+} )();

bin/api-docs/update-api-docs.js

@@ -0,0 +1,218 @@
+/**
+ * External dependencies
+ */
+const { join, relative, resolve, sep, dirname } = require( 'path' );
+const glob = require( 'fast-glob' );
+const execa = require( 'execa' );
+const { Transform } = require( 'stream' );
+const { readFile } = require( 'fs' ).promises;
+
+/**
+ * README file tokens, defined as a tuple of token identifier, source path.
+ *
+ * @typedef {[string,string]} WPReadmeFileTokens
+ */
+
+/**
+ * README file data, defined as a tuple of README file path, token details.
+ *
+ * @typedef {[string,WPReadmeFileTokens]} WPReadmeFileData
+ */
+
+/**
+ * Path to root project directory.
+ *
+ * @type {string}
+ */
+const ROOT_DIR = resolve( __dirname, '../..' );
+
+/**
+ * Path to packages directory.
+ *
+ * @type {string}
+ */
+const PACKAGES_DIR = resolve( ROOT_DIR, 'packages' );
+
+/**
+ * Path to data documentation directory.
+ *
+ * @type {string}
+ */
+const DATA_DOCS_DIR = resolve(
+	ROOT_DIR,
+	'docs/designers-developers/developers/data'
+);
+
+/**
+ * Default path to use if the token doesn't include one.
+ *
+ * @see TOKEN_PATTERN
+ */
+const DEFAULT_PATH = 'src/index.js';
+
+/**
+ * Pattern matching start token of a README file.
+ *
+ * @example Delimiter tokens that use the default source file:
+ * <!-- START TOKEN(Autogenerated API docs) -->
+ * // content within will be filled by docgen
+ * <!-- END TOKEN(Autogenerated API docs) -->
+ *
+ * @example Delimiter tokens that use a specific source file:
+ * <!-- START TOKEN(Autogenerated actions|src/actions.js) -->
+ * // content within will be filled by docgen
+ * <!-- END TOKEN(Autogenerated actions|src/actions.js) -->
+ *
+ * @type {RegExp}
+ * @see DEFAULT_PATH
+ */
+const TOKEN_PATTERN = /<!-- START TOKEN\((.+?(?:\|(.+?))?)\) -->/g;
+
+/**
+ * Given an absolute file path, returns the package name.
+ *
+ * @param {string} file Absolute path.
+ *
+ * @return {string} Package name.
+ */
+function getFilePackage( file ) {
+	return relative( PACKAGES_DIR, file ).split( sep )[ 0 ];
+}
+
+/**
+ * Returns an appropriate glob pattern for the packages directory to match
+ * relevant documentation files for a given set of files.
+ *
+ * @param {string[]} files Set of files to match. Pass an empty set to match
+ *                         all packages.
+ *
+ * @return {string} Packages glob pattern.
+ */
+function getPackagePattern( files ) {
+	if ( ! files.length ) {
+		return '*';
+	}
+
+	// Since brace expansion doesn't work with a single package, special-case
+	// the pattern for the singular match.
+	const packages = Array.from( new Set( files.map( getFilePackage ) ) );
+	return packages.length === 1 ? packages[ 0 ] : '{' + packages.join() + '}';
+}
+
+/**
+ * Returns the conventional store name of a given package.
+ *
+ * @param {string} packageName Package name.
+ *
+ * @return {string} Store name.
+ */
+function getPackageStoreName( packageName ) {
+	let storeName = 'core';
+	if ( packageName !== 'core-data' ) {
+		storeName += '/' + packageName;
+	}
+
+	return storeName;
+}
+
+/**
+ * Returns the conventional documentation file name of a given package.
+ *
+ * @param {string} packageName Package name.
+ *
+ * @return {string} Documentation file name.
+ */
+function getDataDocumentationFile( packageName ) {
+	const storeName = getPackageStoreName( packageName );
+	return `data-${ storeName.replace( '/', '-' ) }.md`;
+}
+
+/**
+ * Returns an appropriate glob pattern for the data documentation directory to
+ * match relevant documentation files for a given set of files.
+ *
+ * @param {string[]} files Set of files to match. Pass an empty set to match
+ *                         all packages.
+ *
+ * @return {string} Packages glob pattern.
+ */
+function getDataDocumentationPattern( files ) {
+	if ( ! files.length ) {
+		return '*';
+	}
+
+	// Since brace expansion doesn't work with a single package, special-case
+	// the pattern for the singular match.
+	const filePackages = Array.from( new Set( files.map( getFilePackage ) ) );
+	const docFiles = filePackages.map( getDataDocumentationFile );
+
+	return docFiles.length === 1 ? docFiles[ 0 ] : '{' + docFiles.join() + '}';
+}
+
+/**
+ * Stream transform which filters out README files to include only those
+ * containing matched token pattern, yielding a tuple of the file and its
+ * matched tokens.
+ *
+ * @type {Transform}
+ */
+const filterTokenTransform = new Transform( {
+	objectMode: true,
+
+	async transform( file, _encoding, callback ) {
+		let content;
+		try {
+			content = await readFile( file, 'utf8' );
+		} catch {}
+
+		if ( content ) {
+			const tokens = [];
+
+			for ( const match of content.matchAll( TOKEN_PATTERN ) ) {
+				const [ , token, path = DEFAULT_PATH ] = match;
+				tokens.push( [ token, path ] );
+			}
+
+			if ( tokens.length ) {
+				this.push( [ file, tokens ] );
+			}
+		}
+
+		callback();
+	},
+} );
+
+/**
+ * Optional process arguments for which to generate documentation.
+ *
+ * @type {string[]}
+ */
+const files = process.argv.slice( 2 );
+
+glob.stream( [
+	`${ PACKAGES_DIR }/${ getPackagePattern( files ) }/README.md`,
+	`${ DATA_DOCS_DIR }/${ getDataDocumentationPattern( files ) }`,
+] )
+	.pipe( filterTokenTransform )
+	.on( 'data', async ( /** @type {WPReadmeFileData} */ data ) => {
+		const [ file, tokens ] = data;
+		const output = relative( ROOT_DIR, file );
+
+		// Each file can have more than one placeholder content to update, each
+		// represented by tokens. The docgen script updates one token at a time,
+		// so the tokens must be replaced in sequence to prevent the processes
+		// from overriding each other.
+		for ( const [ token, path ] of tokens ) {
+			await execa(
+				join( __dirname, '..', '..', 'node_modules', '.bin', 'docgen' ),
+				[
+					relative( ROOT_DIR, resolve( dirname( file ), path ) ),
+					`--output ${ output }`,
+					'--to-token',
+					`--use-token "${ token }"`,
+					'--ignore "/unstable|experimental/i"',
+				],
+				{ shell: true }
+			);
+		}
+	} );