feat: allow modules.getLocalIdent to return a falsy value (#963)

Author: ziir

package-lock.json

@@ -85,7 +85,7 @@
     "sass-loader": "^7.1.0",
     "standard-version": "^6.0.1",
     "strip-ansi": "^5.2.0",
-    "webpack": "^4.33.0"
+    "webpack": "^4.35.0"
   },
   "keywords": [
     "webpack",

package.json

@@ -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;
       },
     }),
   ];

src/utils.js

@@ -1247,7 +1247,7 @@ exports[`loader should throw error on invalid css syntax: warnings 1`] = `Array
 exports[`loader should throws error when no loader for assets: errors 1`] = `
 Array [
   "ModuleParseError: Module parse failed: Unexpected character '�' (1:0)
-You may need an appropriate loader to handle this file type.
+You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file. See https://webpack.js.org/concepts#loaders
 (Source code omitted for this binary file)",
 ]
 `;

test/__snapshots__/loader.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`] = `