pref: reduce memory consumation

lib/util/entrypoints.js

@@ -86,6 +86,7 @@ module.exports.processExportsField = function processExportsField(
 ) {
 	return createFieldProcessor(
 		buildExportsField(exportsField),
+		"",
 		assertExportsFieldRequest,
 		assertExportTarget
 	);
@@ -100,22 +101,24 @@ module.exports.processImportsField = function processImportsField(
 ) {
 	return createFieldProcessor(
 		buildImportsField(importsField),
+		"#",
 		assertImportsFieldRequest,
 		assertImportTarget
 	);
 };
 
 /**
  * @param {ExportsField | ImportsField} field root
+ * @param {string} prefix Request prefix, for `imports` field it is `#`, for `exports` field it is `./`.
  * @param {(s: string) => string} assertRequest assertRequest
  * @param {(s: string, f: boolean) => void} assertTarget assertTarget
  * @returns {FieldProcessor} field processor
  */
-function createFieldProcessor(field, assertRequest, assertTarget) {
+function createFieldProcessor(field, prefix, assertRequest, assertTarget) {
 	return function fieldProcessor(request, conditionNames) {
 		request = assertRequest(request);
 
-		const match = findMatch(request, field);
+		const match = findMatch(prefix + request, field);
 
 		if (match === null) return [];
 
@@ -570,7 +573,6 @@ function buildExportsField(field) {
  */
 function buildImportsField(field) {
 	const keys = Object.keys(field);
-	const newField = /** @type {ImportsField} */ ({});
 
 	for (let i = 0; i < keys.length; i++) {
 		const key = keys[i];
@@ -596,9 +598,7 @@ function buildImportsField(field) {
 				)})`
 			);
 		}
-
-		newField[key.slice(1)] = field[key];
 	}
 
-	return newField;
+	return field;
 }