Fix some edge cases in preprocess logic

lib/processors/frontmatter.js

@@ -17,12 +17,19 @@ module.exports = {
     preprocess: function(text, filename) {
       // Trim leading and trailing whitespace
       text = text.replace(/^\s+|\s+$/g, '');
+
       // Check if the file begins with frontmatter declaration
       if (text.substring(0,3) === '---') {
-        // Remove the frontmatter
-        var split = text.split('---');
-        text= split.slice(2).join('---');
+        // Find end of frontmatter
+        var matchedDashes = /^---$/m.exec(text.slice(3));
+
+        if (matchedDashes) {
+          var dashStartIndex = matchedDashes.index;
+          var sliceIndex = dashStartIndex + matchedDashes[0].length;
+          return [text.slice(sliceIndex + 3).replace(/^\s+/, '')];
+        }
       }
+
       return [text];  // return an array of strings to lint
     },
 
@@ -43,4 +50,4 @@ module.exports = {
     // Don't autofix lint errors
     supportsAutofix: false
   }
-};
+};

package.json

@@ -12,7 +12,7 @@
   "author": "Douglas Duhaime",
   "main": "lib/index.js",
   "scripts": {
-    "test": "./node_modules/mocha/bin/mocha ./tests/*.js"
+    "test": "mocha ./tests/*.js"
   },
   "dependencies": {
     "lodash": "^4.17.4",

tests/fixtures/basic.js

@@ -0,0 +1,8 @@
+---
+process_with_jekyll: true
+---
+
+// We shouldn't remove this: ---
+var plusOne = function(num) {
+  return num+1;
+};

tests/fixtures/dashesInCode.js

@@ -0,0 +1,4 @@
+---
+frontmatter: true
+---
+x --- y;

tests/fixtures/withDashesInFrontMatter.js

@@ -0,0 +1,4 @@
+---
+propertyKey: "Value with ---"
+---
+var x;

tests/plugin.js

@@ -1,22 +1,19 @@
 var CLIEngine = require('eslint').CLIEngine;
 var plugin = require('../');
 var chai = require('chai');
+var fs = require('fs');
+var path = require('path');
 var should = chai.should();
 var assert = chai.assert;
 
+function getFixturePath(relativePath) {
+  return path.normalize(path.join(__dirname, relativePath));
+}
+
 describe('Tests for frontmatter ESLint processor', function() {
 
   // Specify a sample input file
-  var sample = `
-    ---
-    process_with_jekyll: true
-    ---
-
-    // We shouldn't remove this: ---
-    var plusOne = function(num) {
-      return num+1;
-    };
-  `
+  var sample = fs.readFileSync(getFixturePath("./fixtures/basic.js"), "utf8");
 
   before(function() {
     cli = new CLIEngine({
@@ -36,15 +33,33 @@ describe('Tests for frontmatter ESLint processor', function() {
 
   describe('the preprocess function', function() {
     it('should remove frontmatter', function() {
-      var report = cli.executeOnText(sample, 'sample.js');
       var processed = plugin['processors']['.js']['preprocess'](sample)
       var tripleDashes = processed[0].split('---').length;
       tripleDashes.should.equal(2);
     });
+
     it('should not raise a linting error', function() {
       var report = cli.executeOnText(sample, 'sample.js');
       var errors = report.results[0].messages;
       errors.length.should.equal(0);
     });
+
+    it('should remove all frontmatter even if --- is present in frontmatter', function() {
+      debugger;
+      var withDashes = fs.readFileSync(getFixturePath("./fixtures/withDashesInFrontMatter.js"), "utf8");
+
+      var processed = plugin.processors['.js'].preprocess(withDashes);
+
+      processed[0].should.equal('var x;');
+    });
+
+    it('should not change JS even if --- present in code', function() {
+      debugger;
+      var dashesInCode = fs.readFileSync(getFixturePath("./fixtures/dashesInCode.js"), "utf8");
+
+      var processed = plugin.processors['.js'].preprocess(dashesInCode);
+
+      processed[0].should.equal('x --- y;');
+    });
   });
-});
+});