refactor: convert exportsByName object to map (#4362)

* refactor: convert exportsByName object to map * refactor: use nullish assigment, nullish coalescing * Make Addons properties non-optional Co-authored-by: Lukas Taegert-Atkinson <lukastaegert@users.noreply.github.com> Co-authored-by: Lukas Taegert-Atkinson <lukas.taegert-atkinson@tngtech.com>
rollup · Jan 25, 2022 · f30e6f0 · f30e6f0
1 parent 9eeb6a0
commit f30e6f0
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Showing 3 changed files with 23 additions and 29 deletions.
diff --git a/src/Chunk.ts b/src/Chunk.ts
@@ -143,7 +143,7 @@ export default class Chunk {
 	private dynamicName: string | null = null;
 	private readonly exportNamesByVariable = new Map<Variable, string[]>();
 	private readonly exports = new Set<Variable>();
-	private readonly exportsByName: Record<string, Variable> = Object.create(null);
+	private readonly exportsByName = new Map<string, Variable>();
 	private fileName: string | null = null;
 	private implicitEntryModules: Module[] = [];
 	private readonly implicitlyLoadedBefore = new Set<Chunk>();
@@ -295,7 +295,7 @@ export default class Chunk {
 			for (const [variable, exportNames] of exportNamesByVariable) {
 				this.exportNamesByVariable.set(variable, [...exportNames]);
 				for (const exportName of exportNames) {
-					this.exportsByName[exportName] = variable;
+					this.exportsByName.set(exportName, variable);
 				}
 				remainingExports.delete(variable);
 			}
@@ -503,15 +503,11 @@ export default class Chunk {
 	}
 
 	getChunkName(): string {
-		return (
-			this.name || (this.name = this.outputOptions.sanitizeFileName(this.getFallbackChunkName()))
-		);
+		return (this.name ??= this.outputOptions.sanitizeFileName(this.getFallbackChunkName()));
 	}
 
 	getExportNames(): string[] {
-		return (
-			this.sortedExportNames || (this.sortedExportNames = Object.keys(this.exportsByName).sort())
-		);
+		return (this.sortedExportNames ??= Array.from(this.exportsByName.keys()).sort());
 	}
 
 	getRenderedHash(): string {
@@ -533,7 +529,7 @@ export default class Chunk {
 		hash.update(
 			this.getExportNames()
 				.map(exportName => {
-					const variable = this.exportsByName[exportName];
+					const variable = this.exportsByName.get(exportName)!;
 					return `${relativeId((variable.module as Module).id).replace(/\\/g, '/')}:${
 						variable.name
 					}:${exportName}`;
@@ -741,13 +737,13 @@ export default class Chunk {
 				hasExports,
 				id: this.id,
 				indent: this.indentString,
-				intro: addons.intro!,
+				intro: addons.intro,
 				isEntryFacade:
 					this.outputOptions.preserveModules ||
 					(this.facadeModule !== null && this.facadeModule.info.isEntry),
 				isModuleFacade: this.facadeModule !== null,
 				namedExportsMode: this.exportMode !== 'default',
-				outro: addons.outro!,
+				outro: addons.outro,
 				snippets,
 				usesTopLevelAwait,
 				warn: this.inputOptions.onwarn
@@ -868,14 +864,12 @@ export default class Chunk {
 		existingNames: Record<string, unknown>
 	): string {
 		const hash = createHash();
-		hash.update(
-			[addons.intro, addons.outro, addons.banner, addons.footer].map(addon => addon || '').join(':')
-		);
+		hash.update([addons.intro, addons.outro, addons.banner, addons.footer].join(':'));
 		hash.update(options.format);
 		const dependenciesForHashing = new Set<Chunk | ExternalModule>([this]);
 		for (const current of dependenciesForHashing) {
 			if (current instanceof ExternalModule) {
-				hash.update(':' + current.renderPath);
+				hash.update(`:${current.renderPath}`);
 			} else {
 				hash.update(current.getRenderedHash());
 				hash.update(current.generateId(addons, options, existingNames, false));
@@ -1013,7 +1007,7 @@ export default class Chunk {
 		for (const exportName of this.getExportNames()) {
 			if (exportName[0] === '*') continue;
 
-			const variable = this.exportsByName[exportName];
+			const variable = this.exportsByName.get(exportName)!;
 			if (!(variable instanceof SyntheticNamedExportVariable)) {
 				const module = variable.module;
 				if (module && this.chunkByModule.get(module as Module) !== this) continue;
@@ -1171,7 +1165,7 @@ export default class Chunk {
 				dependency = this.modulesById.get(id) as ExternalModule;
 				imported = exportName = '*';
 			} else {
-				const variable = this.exportsByName[exportName];
+				const variable = this.exportsByName.get(exportName)!;
 				if (variable instanceof SyntheticNamedExportVariable) continue;
 				const module = variable.module!;
 				if (module instanceof Module) {
@@ -1287,7 +1281,7 @@ export default class Chunk {
 	}: NormalizedOutputOptions) {
 		const syntheticExports = new Set<SyntheticNamedExportVariable>();
 		for (const exportName of this.getExportNames()) {
-			const exportVariable = this.exportsByName[exportName];
+			const exportVariable = this.exportsByName.get(exportName)!;
 			if (
 				format !== 'es' &&
 				format !== 'system' &&

diff --git a/src/utils/addons.ts b/src/utils/addons.ts
@@ -3,10 +3,10 @@ import { PluginDriver } from './PluginDriver';
 import { error } from './error';
 
 export interface Addons {
-	banner?: string;
-	footer?: string;
-	intro?: string;
-	outro?: string;
+	banner: string;
+	footer: string;
+	intro: string;
+	outro: string;
 }
 
 const concatSep = (out: string, next: string) => (next ? `${out}\n${next}` : out);

diff --git a/src/utils/exportNames.ts b/src/utils/exportNames.ts
@@ -4,39 +4,39 @@ import { toBase64 } from './base64';
 
 export function assignExportsToMangledNames(
 	exports: ReadonlySet<Variable>,
-	exportsByName: Record<string, Variable>,
+	exportsByName: Map<string, Variable>,
 	exportNamesByVariable: Map<Variable, string[]>
 ): void {
 	let nameIndex = 0;
 	for (const variable of exports) {
 		let [exportName] = variable.name;
-		if (exportsByName[exportName]) {
+		if (exportsByName.has(exportName)) {
 			do {
 				exportName = toBase64(++nameIndex);
 				// skip past leading number identifiers
 				if (exportName.charCodeAt(0) === 49 /* '1' */) {
 					nameIndex += 9 * 64 ** (exportName.length - 1);
 					exportName = toBase64(nameIndex);
 				}
-			} while (RESERVED_NAMES.has(exportName) || exportsByName[exportName]);
+			} while (RESERVED_NAMES.has(exportName) || exportsByName.has(exportName));
 		}
-		exportsByName[exportName] = variable;
+		exportsByName.set(exportName, variable);
 		exportNamesByVariable.set(variable, [exportName]);
 	}
 }
 
 export function assignExportsToNames(
 	exports: ReadonlySet<Variable>,
-	exportsByName: Record<string, Variable>,
+	exportsByName: Map<string, Variable>,
 	exportNamesByVariable: Map<Variable, string[]>
 ): void {
 	for (const variable of exports) {
 		let nameIndex = 0;
 		let exportName = variable.name;
-		while (exportsByName[exportName]) {
+		while (exportsByName.has(exportName)) {
 			exportName = variable.name + '$' + ++nameIndex;
 		}
-		exportsByName[exportName] = variable;
+		exportsByName.set(exportName, variable);
 		exportNamesByVariable.set(variable, [exportName]);
 	}
 }