You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

124 lines
3.5 KiB

/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
const EnvironmentNotSupportAsyncWarning = require("../EnvironmentNotSupportAsyncWarning");
const { JAVASCRIPT_MODULE_TYPE_ESM } = require("../ModuleTypeConstants");
const DynamicExports = require("./DynamicExports");
const HarmonyCompatibilityDependency = require("./HarmonyCompatibilityDependency");
const HarmonyExports = require("./HarmonyExports");
/** @typedef {import("../Module").BuildMeta} BuildMeta */
/** @typedef {import("../javascript/JavascriptParser")} JavascriptParser */
/** @typedef {import("./HarmonyModulesPlugin").HarmonyModulesPluginOptions} HarmonyModulesPluginOptions */
module.exports = class HarmonyDetectionParserPlugin {
/**
* @param {HarmonyModulesPluginOptions} options options
*/
constructor(options) {
const { topLevelAwait = false } = options || {};
this.topLevelAwait = topLevelAwait;
}
/**
* @param {JavascriptParser} parser the parser
* @returns {void}
*/
apply(parser) {
parser.hooks.program.tap("HarmonyDetectionParserPlugin", ast => {
const isStrictHarmony =
parser.state.module.type === JAVASCRIPT_MODULE_TYPE_ESM;
const isHarmony =
isStrictHarmony ||
ast.body.some(
statement =>
statement.type === "ImportDeclaration" ||
statement.type === "ExportDefaultDeclaration" ||
statement.type === "ExportNamedDeclaration" ||
statement.type === "ExportAllDeclaration"
);
if (isHarmony) {
const module = parser.state.module;
const compatDep = new HarmonyCompatibilityDependency();
compatDep.loc = {
start: {
line: -1,
column: 0
},
end: {
line: -1,
column: 0
},
index: -3
};
module.addPresentationalDependency(compatDep);
DynamicExports.bailout(parser.state);
HarmonyExports.enable(parser.state, isStrictHarmony);
parser.scope.isStrict = true;
}
});
parser.hooks.topLevelAwait.tap("HarmonyDetectionParserPlugin", () => {
const module = parser.state.module;
if (!this.topLevelAwait) {
throw new Error(
"The top-level-await experiment is not enabled (set experiments.topLevelAwait: true to enable it)"
);
}
if (!HarmonyExports.isEnabled(parser.state)) {
throw new Error(
"Top-level-await is only supported in EcmaScript Modules"
);
}
/** @type {BuildMeta} */
(module.buildMeta).async = true;
EnvironmentNotSupportAsyncWarning.check(
module,
parser.state.compilation.runtimeTemplate,
"topLevelAwait"
);
});
/**
* @returns {boolean | undefined} true if in harmony
*/
const skipInHarmony = () => {
if (HarmonyExports.isEnabled(parser.state)) {
return true;
}
};
/**
* @returns {null | undefined} null if in harmony
*/
const nullInHarmony = () => {
if (HarmonyExports.isEnabled(parser.state)) {
return null;
}
};
const nonHarmonyIdentifiers = ["define", "exports"];
for (const identifier of nonHarmonyIdentifiers) {
parser.hooks.evaluateTypeof
.for(identifier)
.tap("HarmonyDetectionParserPlugin", nullInHarmony);
parser.hooks.typeof
.for(identifier)
.tap("HarmonyDetectionParserPlugin", skipInHarmony);
parser.hooks.evaluate
.for(identifier)
.tap("HarmonyDetectionParserPlugin", nullInHarmony);
parser.hooks.expression
.for(identifier)
.tap("HarmonyDetectionParserPlugin", skipInHarmony);
parser.hooks.call
.for(identifier)
.tap("HarmonyDetectionParserPlugin", skipInHarmony);
}
}
};