webpack/lib/APIPlugin.js

Packs CommonJs/AMD modules for the browser. Allows to split your codebase into multiple bundles, which can be loaded on demand. Support 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 WebpackError = require("./WebpackError");
const ConstDependency = require("./dependencies/ConstDependency");
const BasicEvaluatedExpression = require("./javascript/BasicEvaluatedExpression");
const {
	toConstantDependency,
	evaluateToString
} = require("./javascript/JavascriptParserHelpers");
const ChunkNameRuntimeModule = require("./runtime/ChunkNameRuntimeModule");
const GetFullHashRuntimeModule = require("./runtime/GetFullHashRuntimeModule");

/** @typedef {import("./Compiler")} Compiler */
/** @typedef {import("./javascript/JavascriptParser")} JavascriptParser */

/* eslint-disable camelcase */
const REPLACEMENTS = {
	__webpack_require__: {
		expr: RuntimeGlobals.require,
		req: [RuntimeGlobals.require],
		type: "function",
		assign: false
	},
	__webpack_public_path__: {
		expr: RuntimeGlobals.publicPath,
		req: [RuntimeGlobals.publicPath],
		type: "string",
		assign: true
	},
	__webpack_base_uri__: {
		expr: RuntimeGlobals.baseURI,
		req: [RuntimeGlobals.baseURI],
		type: "string",
		assign: true
	},
	__webpack_modules__: {
		expr: RuntimeGlobals.moduleFactories,
		req: [RuntimeGlobals.moduleFactories],
		type: "object",
		assign: false
	},
	__webpack_chunk_load__: {
		expr: RuntimeGlobals.ensureChunk,
		req: [RuntimeGlobals.ensureChunk],
		type: "function",
		assign: true
	},
	__non_webpack_require__: {
		expr: "require",
		req: null,
		type: undefined, // type is not known, depends on environment
		assign: true
	},
	__webpack_nonce__: {
		expr: RuntimeGlobals.scriptNonce,
		req: [RuntimeGlobals.scriptNonce],
		type: "string",
		assign: true
	},
	__webpack_hash__: {
		expr: `${RuntimeGlobals.getFullHash}()`,
		req: [RuntimeGlobals.getFullHash],
		type: "string",
		assign: false
	},
	__webpack_chunkname__: {
		expr: RuntimeGlobals.chunkName,
		req: [RuntimeGlobals.chunkName],
		type: "string",
		assign: false
	},
	__webpack_get_script_filename__: {
		expr: RuntimeGlobals.getChunkScriptFilename,
		req: [RuntimeGlobals.getChunkScriptFilename],
		type: "function",
		assign: true
	},
	__webpack_runtime_id__: {
		expr: RuntimeGlobals.runtimeId,
		req: [RuntimeGlobals.runtimeId],
		assign: false
	},
	"require.onError": {
		expr: RuntimeGlobals.uncaughtErrorHandler,
		req: [RuntimeGlobals.uncaughtErrorHandler],
		type: undefined, // type is not known, could be function or undefined
		assign: true // is never a pattern
	},
	__system_context__: {
		expr: RuntimeGlobals.systemContext,
		req: [RuntimeGlobals.systemContext],
		type: "object",
		assign: false
	},
	__webpack_share_scopes__: {
		expr: RuntimeGlobals.shareScopeMap,
		req: [RuntimeGlobals.shareScopeMap],
		type: "object",
		assign: false
	},
	__webpack_init_sharing__: {
		expr: RuntimeGlobals.initializeSharing,
		req: [RuntimeGlobals.initializeSharing],
		type: "function",
		assign: true
	}
};
/* eslint-enable camelcase */

class APIPlugin {
	/**
	 * Apply the plugin
	 * @param {Compiler} compiler the compiler instance
	 * @returns {void}
	 */
	apply(compiler) {
		compiler.hooks.compilation.tap(
			"APIPlugin",
			(compilation, { normalModuleFactory }) => {
				compilation.dependencyTemplates.set(
					ConstDependency,
					new ConstDependency.Template()
				);

				compilation.hooks.runtimeRequirementInTree
					.for(RuntimeGlobals.chunkName)
					.tap("APIPlugin", chunk => {
						compilation.addRuntimeModule(
							chunk,
							new ChunkNameRuntimeModule(chunk.name)
						);
						return true;
					});

				compilation.hooks.runtimeRequirementInTree
					.for(RuntimeGlobals.getFullHash)
					.tap("APIPlugin", (chunk, set) => {
						compilation.addRuntimeModule(chunk, new GetFullHashRuntimeModule());
						return true;
					});

				/**
				 * @param {JavascriptParser} parser the parser
				 */
				const handler = parser => {
					Object.keys(REPLACEMENTS).forEach(key => {
						const info = REPLACEMENTS[key];
						parser.hooks.expression
							.for(key)
							.tap(
								"APIPlugin",
								toConstantDependency(parser, info.expr, info.req)
							);
						if (info.assign === false) {
							parser.hooks.assign.for(key).tap("APIPlugin", expr => {
								const err = new WebpackError(`${key} must not be assigned`);
								err.loc = expr.loc;
								throw err;
							});
						}
						if (info.type) {
							parser.hooks.evaluateTypeof
								.for(key)
								.tap("APIPlugin", evaluateToString(info.type));
						}
					});

					parser.hooks.expression
						.for("__webpack_layer__")
						.tap("APIPlugin", expr => {
							const dep = new ConstDependency(
								JSON.stringify(parser.state.module.layer),
								expr.range
							);
							dep.loc = expr.loc;
							parser.state.module.addPresentationalDependency(dep);
							return true;
						});
					parser.hooks.evaluateIdentifier
						.for("__webpack_layer__")
						.tap("APIPlugin", expr =>
							(parser.state.module.layer === null
								? new BasicEvaluatedExpression().setNull()
								: new BasicEvaluatedExpression().setString(
										parser.state.module.layer
								  )
							).setRange(expr.range)
						);
					parser.hooks.evaluateTypeof
						.for("__webpack_layer__")
						.tap("APIPlugin", expr =>
							new BasicEvaluatedExpression()
								.setString(
									parser.state.module.layer === null ? "object" : "string"
								)
								.setRange(expr.range)
						);
				};

				normalModuleFactory.hooks.parser
					.for("javascript/auto")
					.tap("APIPlugin", handler);
				normalModuleFactory.hooks.parser
					.for("javascript/dynamic")
					.tap("APIPlugin", handler);
				normalModuleFactory.hooks.parser
					.for("javascript/esm")
					.tap("APIPlugin", handler);
			}
		);
	}
}

module.exports = APIPlugin;