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/*
Author Tobias Koppers @sokra
*/
"use strict";
const Dependency = require("../Dependency");
const Template = require("../Template");
const makeSerializable = require("../util/makeSerializable");
const memoize = require("../util/memoize");
const { ImportPhaseUtils } = require("./ImportPhase");
const ModuleDependency = require("./ModuleDependency");
/** @typedef {import("webpack-sources").ReplaceSource} ReplaceSource */
/** @typedef {import("../AsyncDependenciesBlock")} AsyncDependenciesBlock */
/** @typedef {import("../Dependency").GetConditionFn} GetConditionFn */
/** @typedef {import("../Dependency").RawReferencedExports} RawReferencedExports */
/** @typedef {import("../Dependency").ReferencedExports} ReferencedExports */
/** @typedef {import("../DependencyTemplate").DependencyTemplateContext} DependencyTemplateContext */
/** @typedef {import("../Module")} Module */
/** @typedef {import("../Module").BuildMeta} BuildMeta */
/** @typedef {import("../ModuleGraph")} ModuleGraph */
/** @typedef {import("../javascript/JavascriptParser").ImportAttributes} ImportAttributes */
/** @typedef {import("../javascript/JavascriptParser").Range} Range */
/** @typedef {import("../serialization/ObjectMiddleware").ObjectDeserializerContext} ObjectDeserializerContext */
/** @typedef {import("../serialization/ObjectMiddleware").ObjectSerializerContext} ObjectSerializerContext */
/** @typedef {import("../util/runtime").RuntimeSpec} RuntimeSpec */
/** @typedef {import("./HarmonyImportGuard").DependencyGuard} DependencyGuard */
/** @typedef {import("./ImportPhase").ImportPhaseType} ImportPhaseType */
const getHarmonyImportGuard = memoize(() => require("./HarmonyImportGuard"));
class ImportDependency extends ModuleDependency {
/**
* Creates an instance of ImportDependency.
* @param {string} request the request
* @param {Range} range expression range
* @param {RawReferencedExports | null} referencedExports list of referenced exports
* @param {ImportPhaseType} phase import phase
* @param {ImportAttributes=} attributes import attributes
*/
constructor(request, range, referencedExports, phase, attributes) {
super(request);
this.range = range;
/** @type {RawReferencedExports | null} */
this.referencedExports = referencedExports;
/** @type {ImportPhaseType} */
this.phase = phase;
/** @type {ImportAttributes | undefined} */
this.attributes = attributes;
/** @type {DependencyGuard[] | undefined} */
this.branchGuards = undefined;
// Range of the `import(specifier, options)` second argument, set only when
// it is not a statically extractable attributes object and must therefore
// be evaluated and validated at runtime.
/** @type {Range | undefined} */
this.optionsRange = undefined;
}
get type() {
return "import()";
}
get category() {
return "esm";
}
/**
* Returns function to determine if the connection is active.
* @param {ModuleGraph} moduleGraph module graph
* @returns {null | false | GetConditionFn} function to determine if the connection is active
*/
getCondition(moduleGraph) {
const guards = this.branchGuards;
if (guards === undefined) return null;
return (connection, runtime) =>
!getHarmonyImportGuard().isDeadByGuards(guards, moduleGraph, runtime);
}
/**
* Returns an identifier to merge equal requests.
* @returns {string | null} an identifier to merge equal requests
*/
getResourceIdentifier() {
let str = super.getResourceIdentifier();
// We specifically use this check to avoid writing the default (`evaluation` or `0`) value and save memory
if (this.phase) {
str += `|phase${ImportPhaseUtils.stringify(this.phase)}`;
}
if (this.attributes) {
str += `|attributes${JSON.stringify(this.attributes)}`;
}
return str;
}
/**
* Returns list of exports referenced by this dependency
* @param {ModuleGraph} moduleGraph module graph
* @param {RuntimeSpec} runtime the runtime for which the module is analysed
* @returns {ReferencedExports} referenced exports
*/
getReferencedExports(moduleGraph, runtime) {
if (!this.referencedExports) return Dependency.EXPORTS_OBJECT_REFERENCED;
/** @type {ReferencedExports} */
const refs = [];
for (const referencedExport of this.referencedExports) {
if (referencedExport[0] === "default") {
const selfModule =
/** @type {Module} */
(moduleGraph.getParentModule(this));
const importedModule =
/** @type {Module} */
(moduleGraph.getModule(this));
const exportsType = importedModule.getExportsType(
moduleGraph,
/** @type {BuildMeta} */
(selfModule.buildMeta).strictHarmonyModule
);
if (
exportsType === "default-only" ||
exportsType === "default-with-named"
) {
return Dependency.EXPORTS_OBJECT_REFERENCED;
}
}
refs.push({
name: referencedExport,
canMangle: false,
canInline: false
});
}
return refs;
}
/**
* Serializes this instance into the provided serializer context.
* @param {ObjectSerializerContext} context context
*/
serialize(context) {
context.write(this.range);
context.write(this.referencedExports);
context.write(this.phase);
context.write(this.attributes);
context.write(this.branchGuards);
context.write(this.optionsRange);
super.serialize(context);
}
/**
* Restores this instance from the provided deserializer context.
* @param {ObjectDeserializerContext} context context
*/
deserialize(context) {
this.range = context.read();
this.referencedExports = context.read();
this.phase = context.read();
this.attributes = context.read();
this.branchGuards = context.read();
this.optionsRange = context.read();
super.deserialize(context);
}
}
makeSerializable(ImportDependency, "webpack/lib/dependencies/ImportDependency");
ImportDependency.Template = class ImportDependencyTemplate extends (
ModuleDependency.Template
) {
/**
* Applies the plugin by registering its hooks on the compiler.
* @param {Dependency} dependency the dependency for which the template should be applied
* @param {ReplaceSource} source the current replace source which can be modified
* @param {DependencyTemplateContext} templateContext the context object
* @returns {void}
*/
apply(
dependency,
source,
{
runtimeTemplate,
module,
moduleGraph,
chunkGraph,
runtimeRequirements,
runtime
}
) {
const dep = /** @type {ImportDependency} */ (dependency);
const connection = moduleGraph.getConnection(dep);
// Dead branch: module is excluded and has no id; code is never executed.
if (connection && !connection.isTargetActive(runtime)) {
source.replace(
dep.range[0],
dep.range[1] - 1,
"Promise.resolve(/* dead branch */)"
);
return;
}
const block = /** @type {AsyncDependenciesBlock} */ (
moduleGraph.getParentBlock(dep)
);
let content = runtimeTemplate.moduleNamespacePromise({
chunkGraph,
block,
module: /** @type {Module} */ (moduleGraph.getModule(dep)),
request: dep.request,
strict: /** @type {BuildMeta} */ (module.buildMeta).strictHarmonyModule,
dependency: dep,
message: "import()",
runtimeRequirements,
originModule: module
});
// For source phase imports, unwrap the default export
// import.source() should return the source directly, not a namespace
if (ImportPhaseUtils.isSource(dep.phase)) {
content = `${content}.then(${runtimeTemplate.returningFunction(
'm["default"]',
"m"
)})`;
}
// A non-static second argument must still be evaluated (for its side
// effects and evaluation order) and validated per spec. Keep it in place
// and wrap it in an inline validator that mirrors the runtime checks of
// the spec's `import(specifier, options)` evaluation.
if (dep.optionsRange) {
const validator = runtimeTemplate.basicFunction("o", [
"try {",
Template.indent([
"if (o !== undefined) {",
Template.indent([
'if ((typeof o !== "object" && typeof o !== "function") || o === null) throw new TypeError("The second argument to import() must be an object");',
'var a = o["with"];',
"if (a !== undefined) {",
Template.indent([
'if ((typeof a !== "object" && typeof a !== "function") || a === null) throw new TypeError("The \'with\' option must be an object");',
"for (var k = Object.keys(a), i = 0; i < k.length; i++) {",
Template.indent([
'if (typeof a[k[i]] !== "string") throw new TypeError("Import attribute values must be strings");'
]),
"}"
]),
"}"
]),
"}"
]),
"} catch (e) { return Promise.reject(e); }",
`return ${content};`
]);
source.replace(dep.range[0], dep.optionsRange[0] - 1, `(${validator})(`);
source.replace(dep.optionsRange[1], dep.range[1] - 1, ")");
return;
}
source.replace(dep.range[0], dep.range[1] - 1, content);
}
};
module.exports = ImportDependency;