Added alt-function to support RetinaJS libraries.

.jshintrc

@@ -10,5 +10,8 @@
   "boss": true,
   "eqnull": true,
   "node": true,
-  "es5": true
+  "es5": true,
+  "predef": [
+    "RegExp"
+  ]
 }

Gruntfile.js

@@ -33,7 +33,7 @@ module.exports = function(grunt) {
       test: {
         flatten: true,
         expand: true,
-        src: ['test/fixtures/*.txt'],
+        src: ['test/fixtures/*.{txt,png}'],
         dest: 'tmp/',
       },
     },
@@ -56,6 +56,27 @@ module.exports = function(grunt) {
         },
         src: ['tmp/international.txt']
       },
+      alt_options: {
+        options: {
+            alternatesPattern: /[@_]\dx/
+        },
+        src: ['tmp/Open*.png']
+      },
+      alt_options_default: {
+        src: ['tmp/Default*.png']
+      },
+      alt_options_off: {
+        options: {
+          alternatesPattern: null
+        },
+        src: ['tmp/Off*.png']
+      },
+      alt_options_array: {
+        options: {
+          alternatesPattern: [ /-(hover|active)/, /[@_]\dx/ ]
+        },
+        src: ['tmp/Array*.png']
+      }
     },
 
     // Unit tests.

README.md

@@ -1,7 +1,42 @@
-# grunt-rev [![Build Status](https://travis-ci.org/cbas/grunt-rev.png)](https://travis-ci.org/cbas/grunt-rev)
+# grunt-rev [![Build Status](https://travis-ci.org/TinyCarrier/grunt-rev.png)](https://travis-ci.org/cbas/grunt-rev)
 
 > Static file asset revisioning through content hashing
 
+## About this fork
+
+Added functionality to use the same hash for alternate versions of an image, so that you will be able to use
+frameworks like RetinaJS to support hi-res images for retina displays.
+
+We considered forking RetinaJS instead, however we didn't find a good solution for handling images included in CSS.
+
+Here is an example usage for the alt-feature:
+
+    ...
+    rev: {
+      options: {
+        alternatesPattern: /[@_]\dx/
+      },
+      src: ['tmp/*.png']
+    },
+    ...
+
+Any image files identified by the regexp `[@_]\dx` include the file without this particular pattern, will get the same hash prefix. For example:
+
+    Open-Source-Logo.png <--- the 'original' image
+    Open-Source-Logo@2x.png <--- the alternate version
+
+... becomes:
+
+    3d0793d5.Open-Source-Logo.png
+    3d0793d5.Open-Source-Logo@2x.png
+
+... despite they are different images with different hashes. The hash is calculated from the content of all images.
+
+You can specify `alternatesPattern` as a `RegExp` object or an array of `RegExp`.
+
+* `/[@_]\dx/` is the default regular expression for `alternatesPattern`
+* To turn off `alternatesPattern` set it to `null`
+
 ## Getting Started
 _If you haven't used [grunt][] before, be sure to check out the [Getting Started][] guide._
 

package.json

@@ -1,7 +1,7 @@
 {
   "name": "grunt-rev",
   "description": "Static file asset revisioning through content hashing",
-  "version": "0.1.0",
+  "version": "0.2.0",
   "homepage": "https://github.com/cbas/grunt-rev",
   "author": {
     "name": "Sebastiaan Deckers",
@@ -38,4 +38,4 @@
   "keywords": [
     "gruntplugin"
   ]
-}
+}

tasks/rev.js

@@ -15,35 +15,145 @@ var fs = require('fs'),
 module.exports = function(grunt) {
 
   function md5(filepath, algorithm, encoding, fileEncoding) {
-    var hash = crypto.createHash(algorithm);
-    grunt.log.verbose.write('Hashing ' + filepath + '...');
-    hash.update(grunt.file.read(filepath), fileEncoding);
+    var hash = crypto.createHash(algorithm), i;
+    if (grunt.util.kindOf(filepath) === 'array') {
+      grunt.log.verbose.write('Hashing group "' + filepath.join('", "') + '" ...');
+      for (i = 0; i < filepath.length; i += 1) {
+        hash.update(grunt.file.read(filepath[i]), fileEncoding);
+      }
+    } else {
+      grunt.log.verbose.write('Hashing ' + filepath + '...');
+      hash.update(grunt.file.read(filepath), fileEncoding);
+    }
     return hash.digest(encoding);
   }
 
+  function findMatchingFiles(matchData, matchDataAll) {
+    var baseFilename = matchData[1] + matchData[3],
+      machingFiles = [baseFilename], i;
+    for (i = 0; i < matchDataAll.length; i += 1) {
+      if (matchData[1] === matchDataAll[i][1] && matchData[3] === matchDataAll[i][3]) {
+        machingFiles.push(matchDataAll[i][0]);
+      }
+    }
+
+    return machingFiles;
+  }
+
+  function combineGroups(pattern, matchData) {
+    var groups = [],
+      iFiles, filesLength = matchData.matching.length,
+      matchingFiles,
+      matchedNames = [];
+
+    for (iFiles = 0; iFiles < filesLength; iFiles += 1) {
+      if (matchedNames.indexOf(matchData.matching[iFiles][0]) >= 0) {
+        continue;
+      }
+      matchingFiles = findMatchingFiles(matchData.matching[iFiles], matchData.matching);
+      matchedNames = matchedNames.concat(matchingFiles);
+      groups.push(matchingFiles);
+    }
+
+    return groups;
+  }
+
   grunt.registerMultiTask('rev', 'Prefix static asset file names with a content hash', function() {
 
     var options = this.options({
+      alternatesPattern: /[@_]\dx/,
       encoding: 'utf8',
       algorithm: 'md5',
       length: 8
     });
 
+    var alternatesPatterns = [];
+    if (options.alternatesPattern === null) {
+      alternatesPatterns = [];
+    } else if (grunt.util.kindOf(options.alternatesPattern) === 'array') {
+      alternatesPatterns = options.alternatesPattern;
+    } else {
+      alternatesPatterns = [options.alternatesPattern];
+    }
+
+    var i, match, regexp, tempRegexp, tempRegexpFunction, numRegexpGroups,
+      regexps = [],
+      matchingFiles = {},
+      patternsLength = alternatesPatterns.length;
+
+    tempRegexpFunction = function($0, $1) {
+        return $1 ? $0 : '###';
+    };
+
+    // Prepare regexps
+    for (i = 0; i < patternsLength; i += 1) {
+      if (grunt.util.kindOf(alternatesPatterns[i]) !== 'regexp') {
+        grunt.fatal('alternates pattern must be a regular expression');
+      }
+      tempRegexp = alternatesPatterns[i].source.replace(/(\\)?\(/g, tempRegexpFunction);
+      numRegexpGroups = tempRegexp.split('###').length - 1;
+      regexp = new RegExp('^(.*)(' + alternatesPatterns[i].source + ')(\\.(?:jpg|png|gif|webp))$');
+      regexps.push(regexp);
+      matchingFiles[alternatesPatterns[i].source] = { regexp: regexp, numRegexpGroups: numRegexpGroups, matching: [] };
+    }
+
+    // Find matching files
+    var matchData;
     this.files.forEach(function(filePair) {
       filePair.src.forEach(function(f) {
+        for (i = 0; i < patternsLength; i += 1) {
+          match = regexps[i].exec(f);
+          matchData = matchingFiles[alternatesPatterns[i].source];
+          if (match !== null) {
+            matchData.matching.push([match[0], match[1], match[2], match[3 + matchData.numRegexpGroups]]);
+            // Limitation: a file can only match one pattern
+            break;
+          }
+        }
+      });
+    });
 
-        var hash = md5(f, options.algorithm, 'hex', options.encoding),
-          prefix = hash.slice(0, options.length),
-          renamed = [prefix, path.basename(f)].join('.'),
-          outPath = path.resolve(path.dirname(f), renamed);
+    // Combine into groups
+    var combinedGroups, pattern, groups = [];
+    for (pattern in matchingFiles) {
+      if (matchingFiles.hasOwnProperty(pattern)) {
+        combinedGroups = combineGroups(pattern, matchingFiles[pattern]);
+        groups = groups.concat(combinedGroups);
+      }
+    }
+
+    // Handle groups
+    var group, j, k, hash, prefix, renamed, outPath, f, handledFiles = [];
+    for (k = 0; k < groups.length; k += 1) {
+      group = groups[k];
+      hash = md5(group, options.algorithm, 'hex', options.encoding);
+      prefix = hash.slice(0, options.length);
+      grunt.verbose.ok(hash);
+      for (j = 0; j < group.length; j += 1) {
+        f = group[j];
+        renamed = [prefix, path.basename(f)].join('.');
+        outPath = path.resolve(path.dirname(f), renamed);
 
-        grunt.verbose.ok().ok(hash);
         fs.renameSync(f, outPath);
         grunt.log.write(f + ' ').ok(renamed);
+        handledFiles.push(f);
+      }
+    }
+
+    // Handle the rest of the files
+    this.files.forEach(function(filePair) {
+      filePair.src.forEach(function(f) {
+        if (handledFiles.indexOf(f) < 0) {
+          hash = md5(f, options.algorithm, 'hex', options.encoding);
+          prefix = hash.slice(0, options.length);
+          renamed = [prefix, path.basename(f)].join('.');
+          outPath = path.resolve(path.dirname(f), renamed);
 
+          grunt.verbose.ok().ok(hash);
+          fs.renameSync(f, outPath);
+          grunt.log.write(f + ' ').ok(renamed);
+        }
       });
     });
-
   });
-
 };

test/rev_test.js

@@ -49,6 +49,65 @@ exports.rev = {
     var exists = grunt.file.exists('tmp/faa07745.international.txt');
     test.ok(exists, '8 character MD5 hash prefix for international content');
 
+    test.done();
+  },
+  alt_options: function(test) {
+    test.expect(6);
+
+    var existsOriginal = grunt.file.exists('tmp/ecea3614.Open-Source-Logo.png');
+    test.ok(existsOriginal, '8 character MD5 hash prefix for original image 1');
+    var existsAlt = grunt.file.exists('tmp/ecea3614.Open-Source-Logo@2x.png');
+    test.ok(existsAlt, '8 character MD5 hash prefix for alt image 1 @ 2x');
+    var existsAlt2 = grunt.file.exists('tmp/ecea3614.Open-Source-Logo@2x.png');
+    test.ok(existsAlt2, '8 character MD5 hash prefix for alt image 1 @ 4x');
+
+    var existsOriginalV2 = grunt.file.exists('tmp/de0ee580.Open-Source-Divider.png');
+    test.ok(existsOriginalV2, '8 character MD5 hash prefix for original image 2');
+    var existsAltV2 = grunt.file.exists('tmp/de0ee580.Open-Source-Divider@2x.png');
+    test.ok(existsAlt, '8 character MD5 hash prefix for alt image 2 @ 2x');
+
+    var existsAltNo = grunt.file.exists('tmp/9aa33131.Open-Source-Logo-No-Alt.png');
+    test.ok(existsAltNo, '8 character MD5 hash prefix for not alt image');
+
+    test.done();
+  },
+  alt_options_default: function(test) {
+    test.expect(2);
+
+    var existsOriginal = grunt.file.exists('tmp/45c45315.Default-Source-Logo.png');
+    test.ok(existsOriginal, '8 character MD5 hash prefix for original image');
+    var existsAlt = grunt.file.exists('tmp/45c45315.Default-Source-Logo_2x.png');
+    test.ok(existsAlt, '8 character MD5 hash prefix for alt image');
+
+    test.done();
+  },
+  alt_options_off: function(test) {
+    test.expect(2);
+
+    var existsOriginal = grunt.file.exists('tmp/89e088f6.Off-Source-Logo.png');
+    test.ok(existsOriginal, '8 character MD5 hash prefix for original image');
+    var existsAlt = grunt.file.exists('tmp/66ff15cd.Off-Source-Logo@2x.png');
+    test.ok(existsAlt, '8 character MD5 hash prefix for alt image');
+
+    test.done();
+  },
+  alt_options_array: function(test) {
+    test.expect(6);
+
+    var exists, expectedFiles = [
+     'tmp/c6aa5421.Array-Source-button.png',
+     'tmp/c6aa5421.Array-Source-button-hover.png',
+     'tmp/c6aa5421.Array-Source-button-active.png',
+     'tmp/a09661e5.Array-Source-Logo.png',
+     'tmp/a09661e5.Array-Source-Logo_2x.png',
+     'tmp/a09661e5.Array-Source-Logo_4x.png'
+    ];
+
+    for (var i = 0; i < expectedFiles.length; i++) {
+      exists = grunt.file.exists(expectedFiles[i]);
+      test.ok(exists, 'File expected: ' + expectedFiles[i]);
+    }
+
     test.done();
   }
 };