feat: allow modules.getLocalIdent to return a falsy value

Author: Tim

src/utils.js

@@ -141,7 +141,7 @@ function getModulesPlugins(options, loaderContext) {
     extractImports(),
     modulesScope({
       generateScopedName: function generateScopedName(exportName) {
-        return modulesOptions.getLocalIdent(
+        let localIdent = modulesOptions.getLocalIdent(
           loaderContext,
           modulesOptions.localIdentName,
           exportName,
@@ -151,6 +151,21 @@ function getModulesPlugins(options, loaderContext) {
             regExp: modulesOptions.localIdentRegExp,
           }
         );
+
+        if (!localIdent) {
+          localIdent = getLocalIdent(
+            loaderContext,
+            modulesOptions.localIdentName,
+            exportName,
+            {
+              context: modulesOptions.context,
+              hashPrefix: modulesOptions.hashPrefix,
+              regExp: modulesOptions.localIdentRegExp,
+            }
+          );
+        }
+
+        return localIdent;
       },
     }),
   ];

test/__snapshots__/modules-option.test.js.snap

@@ -6201,6 +6201,36 @@ exports.locals = {
 
 exports[`modules composes should supports resolving: warnings 1`] = `Array []`;
 
+exports[`modules getLocalIdent should be allowed to return false: errors 1`] = `Array []`;
+
+exports[`modules getLocalIdent should be allowed to return false: locals 1`] = `
+Object {
+  "abc": "abc",
+  "def": "def",
+  "ghi": "ghi",
+  "jkl": "jkl",
+}
+`;
+
+exports[`modules getLocalIdent should be allowed to return false: module (evaluated) 1`] = `
+Array [
+  Array [
+    1,
+    ".abc .def {
+  color: red;
+}
+
+.ghi .jkl {
+  color: blue;
+}
+",
+    "",
+  ],
+]
+`;
+
+exports[`modules getLocalIdent should be allowed to return false: warnings 1`] = `Array []`;
+
 exports[`modules issue #286: errors 1`] = `Array []`;
 
 exports[`modules issue #286: module (evaluated) 1`] = `

test/modules-option.test.js

@@ -312,6 +312,29 @@ describe('modules', () => {
     expect(stats.compilation.errors).toMatchSnapshot('errors');
   });
 
+  it('getLocalIdent should be allowed to return false', async () => {
+    const config = {
+      loader: {
+        options: {
+          modules: {
+            localIdentName: '[local]',
+            getLocalIdent: () => false,
+          },
+        },
+      },
+    };
+    const testId = './modules/getLocalIdent.css';
+    const stats = await webpack(testId, config);
+    const { modules } = stats.toJson();
+    const module = modules.find((m) => m.id === testId);
+    const evaluatedModule = evaluated(module.source);
+
+    expect(evaluatedModule).toMatchSnapshot('module (evaluated)');
+    expect(evaluatedModule.locals).toMatchSnapshot('locals');
+    expect(stats.compilation.warnings).toMatchSnapshot('warnings');
+    expect(stats.compilation.errors).toMatchSnapshot('errors');
+  });
+
   it('composes should supports resolving', async () => {
     const config = {
       loader: { options: { import: true, modules: true } },