gree_leran/node_modules/webpack/lib/util/chainedImports.js

98 lines
4.2 KiB
JavaScript

/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
/** @typedef {import("../Dependency")} Dependency */
/** @typedef {import("../Module")} Module */
/** @typedef {import("../ModuleGraph")} ModuleGraph */
/** @typedef {import("../javascript/JavascriptParser").Range} Range */
/**
* @summary Get the subset of ids and their corresponding range in an id chain that should be re-rendered by webpack.
* Only those in the chain that are actually referring to namespaces or imports should be re-rendered.
* Deeper member accessors on the imported object should not be re-rendered. If deeper member accessors are re-rendered,
* there is a potential loss of meaning with rendering a quoted accessor as an unquoted accessor, or vice versa,
* because minifiers treat quoted accessors differently. e.g. import { a } from "./module"; a["b"] vs a.b
* @param {string[]} untrimmedIds chained ids
* @param {Range} untrimmedRange range encompassing allIds
* @param {Range[] | undefined} ranges cumulative range of ids for each of allIds
* @param {ModuleGraph} moduleGraph moduleGraph
* @param {Dependency} dependency dependency
* @returns {{trimmedIds: string[], trimmedRange: Range}} computed trimmed ids and cumulative range of those ids
*/
exports.getTrimmedIdsAndRange = (
untrimmedIds,
untrimmedRange,
ranges,
moduleGraph,
dependency
) => {
let trimmedIds = trimIdsToThoseImported(
untrimmedIds,
moduleGraph,
dependency
);
let trimmedRange = untrimmedRange;
if (trimmedIds.length !== untrimmedIds.length) {
// The array returned from dep.idRanges is right-aligned with the array returned from dep.names.
// Meaning, the two arrays may not always have the same number of elements, but the last element of
// dep.idRanges corresponds to [the expression fragment to the left of] the last element of dep.names.
// Use this to find the correct replacement range based on the number of ids that were trimmed.
const idx =
ranges === undefined
? -1 /* trigger failure case below */
: ranges.length + (trimmedIds.length - untrimmedIds.length);
if (idx < 0 || idx >= /** @type {Range[]} */ (ranges).length) {
// cspell:ignore minifiers
// Should not happen but we can't throw an error here because of backward compatibility with
// external plugins in wp5. Instead, we just disable trimming for now. This may break some minifiers.
trimmedIds = untrimmedIds;
// TODO webpack 6 remove the "trimmedIds = ids" above and uncomment the following line instead.
// throw new Error("Missing range starts data for id replacement trimming.");
} else {
trimmedRange = /** @type {Range[]} */ (ranges)[idx];
}
}
return { trimmedIds, trimmedRange };
};
/**
* @summary Determine which IDs in the id chain are actually referring to namespaces or imports,
* and which are deeper member accessors on the imported object.
* @param {string[]} ids untrimmed ids
* @param {ModuleGraph} moduleGraph moduleGraph
* @param {Dependency} dependency dependency
* @returns {string[]} trimmed ids
*/
function trimIdsToThoseImported(ids, moduleGraph, dependency) {
/** @type {string[]} */
let trimmedIds = [];
let currentExportsInfo = moduleGraph.getExportsInfo(
/** @type {Module} */ (moduleGraph.getModule(dependency))
);
for (let i = 0; i < ids.length; i++) {
if (i === 0 && ids[i] === "default") {
continue; // ExportInfo for the next level under default is still at the root ExportsInfo, so don't advance currentExportsInfo
}
const exportInfo = currentExportsInfo.getExportInfo(ids[i]);
if (exportInfo.provided === false) {
// json imports have nested ExportInfo for elements that things that are not actually exported, so check .provided
trimmedIds = ids.slice(0, i);
break;
}
const nestedInfo = exportInfo.getNestedExportsInfo();
if (!nestedInfo) {
// once all nested exports are traversed, the next item is the actual import so stop there
trimmedIds = ids.slice(0, i + 1);
break;
}
currentExportsInfo = nestedInfo;
}
// Never trim to nothing. This can happen for invalid imports (e.g. import { notThere } from "./module", or import { anything } from "./missingModule")
return trimmedIds.length ? trimmedIds : ids;
}