added filename argument to the [pre]processCss functions

Author: mightyaleksey

src/index.js

@@ -97,7 +97,7 @@ function fetch(_to, _from, _trace) {
   }
 
   const rootRelativePath = sep + relative(rootDir, filename);
-  const CSSSource = preProcess(readFileSync(filename, 'utf8'));
+  const CSSSource = preProcess(readFileSync(filename, 'utf8'), filename);
 
   const lazyResult = postcss(plugins.concat(new Parser({ fetch, filename, trace })))
     .process(CSSSource, assign(lazyResultOpts, {from: rootRelativePath}));
@@ -109,7 +109,7 @@ function fetch(_to, _from, _trace) {
   tokensByFile[filename] = tokens;
 
   if (postProcess) {
-    postProcess(lazyResult.css);
+    postProcess(lazyResult.css, filename);
   }
 
   return tokens;

test/public-api.js

@@ -8,7 +8,32 @@ describe('public api', () => {
     delete require.cache[require.resolve('awesome-theme/oceanic.css')];
   });
 
-  describe('preprocessCss', () => {
+  describe('preprocessCss()', () => {
+    describe('content of the file and filename are provided to the preprocessCss function', () => {
+      let providedCSS;
+      let providedFilename;
+
+      beforeEach(() => {
+        const spy = (content, filename) => {
+          providedCSS = content;
+          providedFilename = filename;
+          return content;
+        };
+
+        hook({preprocessCss: spy});
+        require('awesome-theme/oceanic.css');
+      });
+
+      it('content of file should be provided', () => {
+        equal(typeof providedCSS, 'string');
+        ok(providedCSS.length);
+      });
+
+      it('filename should be provided', () => {
+        equal(providedFilename, require.resolve('awesome-theme/oceanic.css'));
+      });
+    });
+
     describe('providing empty string constantly', () => {
       before(() => hook({preprocessCss: constant('')}));
 
@@ -27,4 +52,29 @@ describe('public api', () => {
       });
     });
   });
+
+  describe('processCss()', () => {
+    let providedCSS;
+    let providedFilename;
+
+    beforeEach(() => {
+      const spy = (content, filename) => {
+        providedCSS = content;
+        providedFilename = filename;
+        return content;
+      };
+
+      hook({processCss: spy});
+      require('awesome-theme/oceanic.css');
+    });
+
+    it('content of file should be provided', () => {
+      equal(typeof providedCSS, 'string');
+      ok(providedCSS.length);
+    });
+
+    it('filename should be provided', () => {
+      equal(providedFilename, require.resolve('awesome-theme/oceanic.css'));
+    });
+  });
 });