Allow for looking up modules using old name paths.

If an app is referencing a CSS Module using its package name instead of
the moduleName, show a warning and remap to the updated path.

Author: Tim Lindvall

packages/ember-css-modules/lib/modules-preprocessor.js

@@ -15,6 +15,18 @@ module.exports = class ModulesPreprocessor {
     this._modulesTree = null;
     this._modulesBasePath = null;
     this._modulesBridge = new Bridge();
+
+    /*
+     * The addon name we should use to look up modules.
+     * Uses moduleName if defined, else uses the parent/package name.
+     */
+    this._ownerName = null;
+
+    /*
+     * The parent/package name. This is used as a fallback to look up
+     * paths that may reference the package name instead of the
+     * module name. (See resolve-path.js)
+     */
     this._parentName = null;
   }
 
@@ -41,13 +53,14 @@ module.exports = class ModulesPreprocessor {
       // If moduleName is defined, that should override the parent's name.
       // Otherwise, the template and generated module will disagree as to what the path should be.
       let ownerParent = this.owner.getParent();
-      let parentName = ownerParent.moduleName ? ownerParent.moduleName() : this.owner.getParentName();
-      this._parentName = parentName;
+      this._parentName = this.owner.getParentName();
+      let ownerName = ownerParent.moduleName ? ownerParent.moduleName() : this._parentName;
+      this._ownerName = ownerName;
 
       let modulesSources = new ModuleSourceFunnel(inputRoot, modulesInput, {
         include: ['**/*.' + this.owner.getFileExtension()],
         outputRoot,
-        parentName,
+        parentName: ownerName,
       });
 
       let modulesTree = new (require('broccoli-css-modules'))(modulesSources, {
@@ -191,10 +204,12 @@ module.exports = class ModulesPreprocessor {
 
     return this._resolvePath(importPath, fromFile, {
       defaultExtension: this.owner.getFileExtension(),
-      ownerName: this._parentName,
+      ownerName: this._ownerName,
+      parentName: this._parentName,
       addonModulesRoot: this.owner.getAddonModulesRoot(),
       root: ensurePosixPath(this._modulesTree.inputPaths[0]),
-      parent: this.owner.getParent()
+      parent: this.owner.getParent(),
+      ui: this.owner.ui
     });
   }
 };

packages/ember-css-modules/lib/resolve-path.js

@@ -10,6 +10,16 @@ module.exports = function resolvePath(importPath, fromFile, options) {
     return resolveRelativePath(pathWithExtension, fromFile, options);
   } else if (isLocalPath(pathWithExtension, options)) {
     return resolveLocalPath(pathWithExtension, fromFile, options);
+  } else if (isLocalPathWithOldPackageNameRef(pathWithExtension, options)) {
+    const amendedPathWithExtension = pathWithExtension.replace(options.parentName, options.ownerName);
+    options.ui.writeWarnLine(
+      'For addons that define a moduleName, you should reference any CSS Modules provided by that addon ' +
+      'using its moduleName instead of the package name.\n' +
+      'Current path: ' + importPath + '\n' +
+      'Replace with: ' + importPath.replace(options.parentName, options.ownerName) + '\n' +
+      'File: ' + fromFile
+    );
+    return resolveLocalPath(amendedPathWithExtension, fromFile, options);
   } else {
     return resolveExternalPath(pathWithExtension, importPath, fromFile, options);
   }
@@ -23,6 +33,10 @@ function isLocalPath(importPath, options) {
   return importPath.indexOf(options.ownerName + '/') === 0;
 }
 
+function isLocalPathWithOldPackageNameRef(importPath, options) {
+  return (options.ownerName !== options.parentName) && importPath.indexOf(options.parentName + '/') === 0;
+}
+
 function resolveRelativePath(importPath, fromFile, options) {
   let absolutePath = ensurePosixPath(path.resolve(path.dirname(fromFile), importPath));
   return internalDep(absolutePath, options);