Fix #120

Author: dfreeman

docs/PREPROCESSORS.md

@@ -49,3 +49,13 @@ cssModules: {
   }
 }
 ```
+
+### Passing Through Other Files
+
+When you configure an `intermediateOutputPath`, ember-css-modules will automatically pass through all files with stylesheet-like extensions for subsequent processors to be able to include. If you're relying on being able to reference data from other files in a downstream processing step, you may configure the extensions of files that should be passed on.
+
+```js
+cssModules: {
+  passthroughFileExtensions: ['json']
+}
+```

index.js

@@ -95,6 +95,10 @@ module.exports = {
     return this.project;
   },
 
+  getPassthroughFileExtensions() {
+    return this.cssModulesOptions.passthroughFileExtensions || ['css', 'scss', 'sass', 'less', 'styl'];
+  },
+
   getScopedNameGenerator() {
     return this.cssModulesOptions.generateScopedName || require('./lib/generate-scoped-name');
   },

lib/output-styles-preprocessor.js

@@ -5,6 +5,7 @@ const ensurePosixPath = require('ensure-posix-path');
 const Concat = require('broccoli-concat');
 const MergeTrees = require('broccoli-merge-trees');
 const PostCSS = require('broccoli-postcss');
+const Funnel = require('broccoli-funnel');
 
 module.exports = class OutputStylesPreprocessor {
   constructor(options) {
@@ -38,6 +39,10 @@ module.exports = class OutputStylesPreprocessor {
     // If an intermediate output path is specified, we need to pass through the full contents of the styles tree
     // and trust that a subsequent preprocessor will appropriately filter out everything else.
     if (this.owner.getIntermediateOutputPath()) {
+      let passthroughExtensions = this.owner.getPassthroughFileExtensions();
+      if (passthroughExtensions.length) {
+        inputNode = new Funnel(inputNode, { include: passthroughExtensions.map(ext => `**/*.${ext}`) });
+      }
       return new MergeTrees([inputNode, concat], { overwrite: true });
     } else {
       return concat;