webpack/lib/dependencies/AMDDefineDependencyParserPlugin.js

Packs ECMAScript/CommonJs/AMD modules for the browser. Allows you to split your codebase into multiple bundles, which can be loaded on demand. Supports loaders to preprocess files, i.e. json, jsx, es7, css, less, ... and your custom stuff.

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/

"use strict";

const RuntimeGlobals = require("../RuntimeGlobals");
const AMDDefineDependency = require("./AMDDefineDependency");
const AMDRequireArrayDependency = require("./AMDRequireArrayDependency");
const AMDRequireContextDependency = require("./AMDRequireContextDependency");
const AMDRequireItemDependency = require("./AMDRequireItemDependency");
const ConstDependency = require("./ConstDependency");
const ContextDependencyHelpers = require("./ContextDependencyHelpers");
const DynamicExports = require("./DynamicExports");
const LocalModuleDependency = require("./LocalModuleDependency");
const { addLocalModule, getLocalModule } = require("./LocalModulesHelpers");

/** @typedef {import("estree").ArrowFunctionExpression} ArrowFunctionExpression */
/** @typedef {import("estree").CallExpression} CallExpression */
/** @typedef {import("estree").Expression} Expression */
/** @typedef {import("estree").FunctionExpression} FunctionExpression */
/** @typedef {import("estree").Identifier} Identifier */
/** @typedef {import("estree").Literal} Literal */
/** @typedef {import("estree").MemberExpression} MemberExpression */
/** @typedef {import("estree").ObjectExpression} ObjectExpression */
/** @typedef {import("estree").SimpleCallExpression} SimpleCallExpression */
/** @typedef {import("estree").SpreadElement} SpreadElement */
/** @typedef {import("../../declarations/WebpackOptions").JavascriptParserOptions} JavascriptParserOptions */
/** @typedef {import("../Dependency").DependencyLocation} DependencyLocation */
/** @typedef {import("../javascript/BasicEvaluatedExpression")} BasicEvaluatedExpression */
/** @typedef {import("../javascript/JavascriptParser")} JavascriptParser */
/** @typedef {import("../javascript/JavascriptParser").Range} Range */

/**
 * @param {Expression | SpreadElement} expr expression
 * @returns {expr is CallExpression} true if it's a bound function expression
 */
const isBoundFunctionExpression = expr => {
	if (expr.type !== "CallExpression") return false;
	if (expr.callee.type !== "MemberExpression") return false;
	if (expr.callee.computed) return false;
	if (expr.callee.object.type !== "FunctionExpression") return false;
	if (expr.callee.property.type !== "Identifier") return false;
	if (expr.callee.property.name !== "bind") return false;
	return true;
};

/** @typedef {FunctionExpression | ArrowFunctionExpression} UnboundFunctionExpression */

/**
 * @param {Expression | SpreadElement} expr expression
 * @returns {expr is FunctionExpression | ArrowFunctionExpression} true when unbound function expression
 */
const isUnboundFunctionExpression = expr => {
	if (expr.type === "FunctionExpression") return true;
	if (expr.type === "ArrowFunctionExpression") return true;
	return false;
};

/**
 * @param {Expression | SpreadElement} expr expression
 * @returns {expr is FunctionExpression | ArrowFunctionExpression | CallExpression} true when callable
 */
const isCallable = expr => {
	if (isUnboundFunctionExpression(expr)) return true;
	if (isBoundFunctionExpression(expr)) return true;
	return false;
};

class AMDDefineDependencyParserPlugin {
	/**
	 * @param {JavascriptParserOptions} options parserOptions
	 */
	constructor(options) {
		this.options = options;
	}

	/**
	 * @param {JavascriptParser} parser the parser
	 * @returns {void}
	 */
	apply(parser) {
		parser.hooks.call
			.for("define")
			.tap(
				"AMDDefineDependencyParserPlugin",
				this.processCallDefine.bind(this, parser)
			);
	}

	/**
	 * @param {JavascriptParser} parser the parser
	 * @param {CallExpression} expr call expression
	 * @param {BasicEvaluatedExpression} param param
	 * @param {Record<number, string>} identifiers identifiers
	 * @param {string=} namedModule named module
	 * @returns {boolean | undefined} result
	 */
	processArray(parser, expr, param, identifiers, namedModule) {
		if (param.isArray()) {
			const items = /** @type {BasicEvaluatedExpression[]} */ (param.items);
			for (const [idx, item] of items.entries()) {
				if (
					item.isString() &&
					["require", "module", "exports"].includes(
						/** @type {string} */ (item.string)
					)
				)
					identifiers[/** @type {number} */ (idx)] = /** @type {string} */ (
						item.string
					);
				const result = this.processItem(parser, expr, item, namedModule);
				if (result === undefined) {
					this.processContext(parser, expr, item);
				}
			}
			return true;
		} else if (param.isConstArray()) {
			/** @type {(string | LocalModuleDependency | AMDRequireItemDependency)[]} */
			const deps = [];
			const array = /** @type {string[]} */ (param.array);
			for (const [idx, request] of array.entries()) {
				let dep;
				let localModule;
				if (request === "require") {
					identifiers[idx] = request;
					dep = RuntimeGlobals.require;
				} else if (["exports", "module"].includes(request)) {
					identifiers[idx] = request;
					dep = request;
				} else if ((localModule = getLocalModule(parser.state, request))) {
					localModule.flagUsed();
					dep = new LocalModuleDependency(localModule, undefined, false);
					dep.loc = /** @type {DependencyLocation} */ (expr.loc);
					parser.state.module.addPresentationalDependency(dep);
				} else {
					dep = this.newRequireItemDependency(request);
					dep.loc = /** @type {DependencyLocation} */ (expr.loc);
					dep.optional = Boolean(parser.scope.inTry);
					parser.state.current.addDependency(dep);
				}
				deps.push(dep);
			}
			const dep = this.newRequireArrayDependency(
				deps,
				/** @type {Range} */ (param.range)
			);
			dep.loc = /** @type {DependencyLocation} */ (expr.loc);
			dep.optional = Boolean(parser.scope.inTry);
			parser.state.module.addPresentationalDependency(dep);
			return true;
		}
	}

	/**
	 * @param {JavascriptParser} parser the parser
	 * @param {CallExpression} expr call expression
	 * @param {BasicEvaluatedExpression} param param
	 * @param {string=} namedModule named module
	 * @returns {boolean | undefined} result
	 */
	processItem(parser, expr, param, namedModule) {
		if (param.isConditional()) {
			const options = /** @type {BasicEvaluatedExpression[]} */ (param.options);
			for (const item of options) {
				const result = this.processItem(parser, expr, item);
				if (result === undefined) {
					this.processContext(parser, expr, item);
				}
			}

			return true;
		} else if (param.isString()) {
			let dep;
			let localModule;

			if (param.string === "require") {
				dep = new ConstDependency(
					RuntimeGlobals.require,
					/** @type {Range} */ (param.range),
					[RuntimeGlobals.require]
				);
			} else if (param.string === "exports") {
				dep = new ConstDependency(
					"exports",
					/** @type {Range} */ (param.range),
					[RuntimeGlobals.exports]
				);
			} else if (param.string === "module") {
				dep = new ConstDependency(
					"module",
					/** @type {Range} */ (param.range),
					[RuntimeGlobals.module]
				);
			} else if (
				(localModule = getLocalModule(
					parser.state,
					/** @type {string} */ (param.string),
					namedModule
				))
			) {
				localModule.flagUsed();
				dep = new LocalModuleDependency(localModule, param.range, false);
			} else {
				dep = this.newRequireItemDependency(
					/** @type {string} */ (param.string),
					param.range
				);
				dep.optional = Boolean(parser.scope.inTry);
				parser.state.current.addDependency(dep);
				return true;
			}
			dep.loc = /** @type {DependencyLocation} */ (expr.loc);
			parser.state.module.addPresentationalDependency(dep);
			return true;
		}
	}

	/**
	 * @param {JavascriptParser} parser the parser
	 * @param {CallExpression} expr call expression
	 * @param {BasicEvaluatedExpression} param param
	 * @returns {boolean | undefined} result
	 */
	processContext(parser, expr, param) {
		const dep = ContextDependencyHelpers.create(
			AMDRequireContextDependency,
			/** @type {Range} */ (param.range),
			param,
			expr,
			this.options,
			{
				category: "amd"
			},
			parser
		);
		if (!dep) return;
		dep.loc = /** @type {DependencyLocation} */ (expr.loc);
		dep.optional = Boolean(parser.scope.inTry);
		parser.state.current.addDependency(dep);
		return true;
	}

	/**
	 * @param {JavascriptParser} parser the parser
	 * @param {CallExpression} expr call expression
	 * @returns {boolean | undefined} result
	 */
	processCallDefine(parser, expr) {
		/** @type {Expression | SpreadElement | undefined} */
		let array;
		/** @type {FunctionExpression | ArrowFunctionExpression | CallExpression | Identifier | undefined} */
		let fn;
		/** @type {ObjectExpression | Identifier | undefined} */
		let obj;
		/** @type {string | undefined} */
		let namedModule;
		switch (expr.arguments.length) {
			case 1:
				if (isCallable(expr.arguments[0])) {
					// define(f() {…})
					fn = expr.arguments[0];
				} else if (expr.arguments[0].type === "ObjectExpression") {
					// define({…})
					obj = expr.arguments[0];
				} else {
					// define(expr)
					// unclear if function or object
					obj = fn = /** @type {Identifier} */ (expr.arguments[0]);
				}
				break;
			case 2:
				if (expr.arguments[0].type === "Literal") {
					namedModule = /** @type {string} */ (expr.arguments[0].value);
					// define("…", …)
					if (isCallable(expr.arguments[1])) {
						// define("…", f() {…})
						fn = expr.arguments[1];
					} else if (expr.arguments[1].type === "ObjectExpression") {
						// define("…", {…})
						obj = expr.arguments[1];
					} else {
						// define("…", expr)
						// unclear if function or object
						obj = fn = /** @type {Identifier} */ (expr.arguments[1]);
					}
				} else {
					array = expr.arguments[0];
					if (isCallable(expr.arguments[1])) {
						// define([…], f() {})
						fn = expr.arguments[1];
					} else if (expr.arguments[1].type === "ObjectExpression") {
						// define([…], {…})
						obj = expr.arguments[1];
					} else {
						// define([…], expr)
						// unclear if function or object
						obj = fn = /** @type {Identifier} */ (expr.arguments[1]);
					}
				}
				break;
			case 3:
				// define("…", […], f() {…})
				namedModule =
					/** @type {string} */
					(
						/** @type {Literal} */
						(expr.arguments[0]).value
					);
				array = expr.arguments[1];
				if (isCallable(expr.arguments[2])) {
					// define("…", […], f() {})
					fn = expr.arguments[2];
				} else if (expr.arguments[2].type === "ObjectExpression") {
					// define("…", […], {…})
					obj = expr.arguments[2];
				} else {
					// define("…", […], expr)
					// unclear if function or object
					obj = fn = /** @type {Identifier} */ (expr.arguments[2]);
				}
				break;
			default:
				return;
		}
		DynamicExports.bailout(parser.state);
		/** @type {Identifier[] | null} */
		let fnParams = null;
		let fnParamsOffset = 0;
		if (fn) {
			if (isUnboundFunctionExpression(fn)) {
				fnParams =
					/** @type {Identifier[]} */
					(fn.params);
			} else if (isBoundFunctionExpression(fn)) {
				const object =
					/** @type {FunctionExpression} */
					(/** @type {MemberExpression} */ (fn.callee).object);

				fnParams =
					/** @type {Identifier[]} */
					(object.params);
				fnParamsOffset = fn.arguments.length - 1;
				if (fnParamsOffset < 0) {
					fnParamsOffset = 0;
				}
			}
		}
		const fnRenames = new Map();
		if (array) {
			/** @type {Record<number, string>} */
			const identifiers = {};
			const param = parser.evaluateExpression(array);
			const result = this.processArray(
				parser,
				expr,
				param,
				identifiers,
				namedModule
			);
			if (!result) return;
			if (fnParams) {
				fnParams = fnParams.slice(fnParamsOffset).filter((param, idx) => {
					if (identifiers[idx]) {
						fnRenames.set(param.name, parser.getVariableInfo(identifiers[idx]));
						return false;
					}
					return true;
				});
			}
		} else {
			const identifiers = ["require", "exports", "module"];
			if (fnParams) {
				fnParams = fnParams.slice(fnParamsOffset).filter((param, idx) => {
					if (identifiers[idx]) {
						fnRenames.set(param.name, parser.getVariableInfo(identifiers[idx]));
						return false;
					}
					return true;
				});
			}
		}
		/** @type {boolean | undefined} */
		let inTry;
		if (fn && isUnboundFunctionExpression(fn)) {
			inTry = parser.scope.inTry;
			parser.inScope(/** @type {Identifier[]} */ (fnParams), () => {
				for (const [name, varInfo] of fnRenames) {
					parser.setVariable(name, varInfo);
				}
				parser.scope.inTry = /** @type {boolean} */ (inTry);
				if (fn.body.type === "BlockStatement") {
					parser.detectMode(fn.body.body);
					const prev = parser.prevStatement;
					parser.preWalkStatement(fn.body);
					parser.prevStatement = prev;
					parser.walkStatement(fn.body);
				} else {
					parser.walkExpression(fn.body);
				}
			});
		} else if (fn && isBoundFunctionExpression(fn)) {
			inTry = parser.scope.inTry;

			const object =
				/** @type {FunctionExpression} */
				(/** @type {MemberExpression} */ (fn.callee).object);

			parser.inScope(
				/** @type {Identifier[]} */
				(object.params).filter(
					i => !["require", "module", "exports"].includes(i.name)
				),
				() => {
					for (const [name, varInfo] of fnRenames) {
						parser.setVariable(name, varInfo);
					}
					parser.scope.inTry = /** @type {boolean} */ (inTry);

					if (object.body.type === "BlockStatement") {
						parser.detectMode(object.body.body);
						const prev = parser.prevStatement;
						parser.preWalkStatement(object.body);
						parser.prevStatement = prev;
						parser.walkStatement(object.body);
					} else {
						parser.walkExpression(
							/** @type {TODO} */
							(object.body)
						);
					}
				}
			);
			if (fn.arguments) {
				parser.walkExpressions(fn.arguments);
			}
		} else if (fn || obj) {
			parser.walkExpression(
				/** @type {FunctionExpression | ArrowFunctionExpression | CallExpression | ObjectExpression | Identifier} */
				(fn || obj)
			);
		}

		const dep = this.newDefineDependency(
			/** @type {Range} */ (expr.range),
			array ? /** @type {Range} */ (array.range) : null,
			fn ? /** @type {Range} */ (fn.range) : null,
			obj ? /** @type {Range} */ (obj.range) : null,
			namedModule || null
		);
		dep.loc = /** @type {DependencyLocation} */ (expr.loc);
		if (namedModule) {
			dep.localModule = addLocalModule(parser.state, namedModule);
		}
		parser.state.module.addPresentationalDependency(dep);
		return true;
	}

	/**
	 * @param {Range} range range
	 * @param {Range | null} arrayRange array range
	 * @param {Range | null} functionRange function range
	 * @param {Range | null} objectRange object range
	 * @param {string | null} namedModule true, when define is called with a name
	 * @returns {AMDDefineDependency} AMDDefineDependency
	 */
	newDefineDependency(
		range,
		arrayRange,
		functionRange,
		objectRange,
		namedModule
	) {
		return new AMDDefineDependency(
			range,
			arrayRange,
			functionRange,
			objectRange,
			namedModule
		);
	}

	/**
	 * @param {(string | LocalModuleDependency | AMDRequireItemDependency)[]} depsArray deps array
	 * @param {Range} range range
	 * @returns {AMDRequireArrayDependency} AMDRequireArrayDependency
	 */
	newRequireArrayDependency(depsArray, range) {
		return new AMDRequireArrayDependency(depsArray, range);
	}

	/**
	 * @param {string} request request
	 * @param {Range=} range range
	 * @returns {AMDRequireItemDependency} AMDRequireItemDependency
	 */
	newRequireItemDependency(request, range) {
		return new AMDRequireItemDependency(request, range);
	}
}

module.exports = AMDDefineDependencyParserPlugin;