Normalize property accessors for es6 namespaces and chained member/call expressions

lib/dependencies/HarmonyEvaluatedImportSpecifierDependency.js

@@ -35,7 +35,7 @@ class HarmonyEvaluatedImportSpecifierDependency extends HarmonyImportSpecifierDe
 	 * @param {string} operator operator
 	 */
 	constructor(request, sourceOrder, ids, name, range, assertions, operator) {
-		super(request, sourceOrder, ids, name, range, false, assertions);
+		super(request, sourceOrder, ids, name, range, false, assertions, []);
 		this.operator = operator;
 	}
 

lib/dependencies/HarmonyImportDependencyParserPlugin.js

@@ -195,7 +195,8 @@ module.exports = class HarmonyImportDependencyParserPlugin {
 					settings.name,
 					expr.range,
 					exportPresenceMode,
-					settings.assertions
+					settings.assertions,
+					[]
 				);
 				dep.referencedPropertiesInDestructuring =
 					parser.destructuringAssignmentPropertiesFor(expr);
@@ -211,14 +212,19 @@ module.exports = class HarmonyImportDependencyParserPlugin {
 			.for(harmonySpecifierTag)
 			.tap(
 				"HarmonyImportDependencyParserPlugin",
-				(expression, members, membersOptionals) => {
+				(expression, members, membersOptionals, memberRangeStarts) => {
 					const settings = /** @type {HarmonySettings} */ (
 						parser.currentTagData
 					);
 					const nonOptionalMembers = getNonOptionalPart(
 						members,
 						membersOptionals
 					);
+					const rangeStarts = memberRangeStarts.slice(
+						0,
+						memberRangeStarts.length -
+							(members.length - nonOptionalMembers.length)
+					);
 					const expr =
 						nonOptionalMembers !== members
 							? getNonOptionalMemberChain(
@@ -234,7 +240,8 @@ module.exports = class HarmonyImportDependencyParserPlugin {
 						settings.name,
 						expr.range,
 						exportPresenceMode,
-						settings.assertions
+						settings.assertions,
+						rangeStarts
 					);
 					dep.referencedPropertiesInDestructuring =
 						parser.destructuringAssignmentPropertiesFor(expr);
@@ -249,7 +256,7 @@ module.exports = class HarmonyImportDependencyParserPlugin {
 			.for(harmonySpecifierTag)
 			.tap(
 				"HarmonyImportDependencyParserPlugin",
-				(expression, members, membersOptionals) => {
+				(expression, members, membersOptionals, memberRangeStarts) => {
 					const { arguments: args, callee } = expression;
 					const settings = /** @type {HarmonySettings} */ (
 						parser.currentTagData
@@ -258,6 +265,11 @@ module.exports = class HarmonyImportDependencyParserPlugin {
 						members,
 						membersOptionals
 					);
+					const rangeStarts = memberRangeStarts.slice(
+						0,
+						memberRangeStarts.length -
+							(members.length - nonOptionalMembers.length)
+					);
 					const expr =
 						nonOptionalMembers !== members
 							? getNonOptionalMemberChain(
@@ -273,7 +285,8 @@ module.exports = class HarmonyImportDependencyParserPlugin {
 						settings.name,
 						expr.range,
 						exportPresenceMode,
-						settings.assertions
+						settings.assertions,
+						rangeStarts
 					);
 					dep.directImport = members.length === 0;
 					dep.call = true;

lib/dependencies/HarmonyImportSpecifierDependency.js

@@ -43,6 +43,7 @@ class HarmonyImportSpecifierDependency extends HarmonyImportDependency {
 	 * @param {Range} range range
 	 * @param {TODO} exportPresenceMode export presence mode
 	 * @param {Assertions=} assertions assertions
+	 * @param {number[]=} idRangeStarts range starts for members of ids; the two arrays are right-aligned
 	 */
 	constructor(
 		request,
@@ -51,12 +52,14 @@ class HarmonyImportSpecifierDependency extends HarmonyImportDependency {
 		name,
 		range,
 		exportPresenceMode,
-		assertions
+		assertions,
+		idRangeStarts // TODO webpack 6 make this non-optional. It must always be set to properly trim ids.
 	) {
 		super(request, sourceOrder, assertions);
 		this.ids = ids;
 		this.name = name;
 		this.range = range;
+		this.idRangeStarts = idRangeStarts;
 		this.exportPresenceMode = exportPresenceMode;
 		this.namespaceObjectAsContext = false;
 		this.call = undefined;
@@ -258,6 +261,7 @@ class HarmonyImportSpecifierDependency extends HarmonyImportDependency {
 		write(this.ids);
 		write(this.name);
 		write(this.range);
+		write(this.idRangeStarts);
 		write(this.exportPresenceMode);
 		write(this.namespaceObjectAsContext);
 		write(this.call);
@@ -277,6 +281,7 @@ class HarmonyImportSpecifierDependency extends HarmonyImportDependency {
 		this.ids = read();
 		this.name = read();
 		this.range = read();
+		this.idRangeStarts = read();
 		this.exportPresenceMode = read();
 		this.namespaceObjectAsContext = read();
 		this.call = read();
@@ -310,14 +315,75 @@ HarmonyImportSpecifierDependency.Template = class HarmonyImportSpecifierDependen
 		// Skip rendering depending when dependency is conditional
 		if (connection && !connection.isTargetActive(runtime)) return;
 
-		const ids = dep.getIds(moduleGraph);
-		const exportExpr = this._getCodeForIds(dep, source, templateContext, ids);
-		const range = dep.range;
+		const ids = dep.getIds(moduleGraph); // determine minimal set of IDs.
+		let trimmedIds = this._trimIdsToThoseImported(ids, moduleGraph, dep);
+
+		let [rangeStart, rangeEnd] = dep.range;
+		if (trimmedIds.length !== ids.length) {
+			// The array returned from dep.idRangeStarts is right-aligned with the array returned from dep.getIds.
+			// Meaning, the two arrays may not always have the same number of elements, but the last element of
+			// dep.idRangeStarts corresponds to [the starting range position of] the last element of dep.getIds.
+			// Use this to find the correct range end position based on the number of ids that were trimmed.
+			const idx = dep.idRangeStarts.length + (trimmedIds.length - ids.length);
+			if (idx < 0 || idx >= dep.idRangeStarts.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 = ids;
+				// 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 {
+				rangeEnd = dep.idRangeStarts[idx];
+			}
+		}
+
+		const exportExpr = this._getCodeForIds(
+			dep,
+			source,
+			templateContext,
+			trimmedIds
+		);
 		if (dep.shorthand) {
-			source.insert(range[1], `: ${exportExpr}`);
+			source.insert(rangeEnd, `: ${exportExpr}`);
 		} else {
-			source.replace(range[0], range[1] - 1, exportExpr);
+			source.replace(rangeStart, rangeEnd - 1, exportExpr);
+		}
+	}
+
+	/**
+	 * @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.  Only the former should be re-rendered.
+	 * @param {string[]} ids ids
+	 * @param {ModuleGraph} moduleGraph moduleGraph
+	 * @param {HarmonyImportSpecifierDependency} dependency dependency
+	 * @returns {string[]} generated code
+	 */
+	_trimIdsToThoseImported(ids, moduleGraph, dependency) {
+		let trimmedIds = [];
+		const exportsInfo = moduleGraph.getExportsInfo(
+			moduleGraph.getModule(dependency)
+		);
+		let currentExportsInfo = /** @type {ExportsInfo=} */ exportsInfo;
+		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;
 	}
 
 	/**

lib/javascript/BasicEvaluatedExpression.js

@@ -70,6 +70,8 @@ class BasicEvaluatedExpression {
 		this.getMembers = undefined;
 		/** @type {() => boolean[]} */
 		this.getMembersOptionals = undefined;
+		/** @type {() => number[]} */
+		this.getMemberRangeStarts = undefined;
 		/** @type {EsTreeNode} */
 		this.expression = undefined;
 	}
@@ -384,14 +386,22 @@ class BasicEvaluatedExpression {
 	 * @param {string | VariableInfoInterface} rootInfo root info
 	 * @param {() => string[]} getMembers members
 	 * @param {() => boolean[]=} getMembersOptionals optional members
+	 * @param {() => number[]=} getMemberRangeStarts range start of progressively increasing sub-expressions
 	 * @returns {this} this
 	 */
-	setIdentifier(identifier, rootInfo, getMembers, getMembersOptionals) {
+	setIdentifier(
+		identifier,
+		rootInfo,
+		getMembers,
+		getMembersOptionals,
+		getMemberRangeStarts
+	) {
 		this.type = TypeIdentifier;
 		this.identifier = identifier;
 		this.rootInfo = rootInfo;
 		this.getMembers = getMembers;
 		this.getMembersOptionals = getMembersOptionals;
+		this.getMemberRangeStarts = getMemberRangeStarts;
 		this.sideEffects = true;
 		return this;
 	}