Stringify

build/node.js

@@ -2,7 +2,70 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-var GradientParser = {};
+var GradientParser = (GradientParser || {});
+
+GradientParser.stringify = (function() {
+
+  var visitor = {
+
+    'visit_linear-gradient': function(node) {
+      var orientation = visitor.visit(node.orientation);
+      if (orientation) {
+        orientation += ', ';
+      }
+
+      return 'linear-gradient('+ orientation + visitor.visit(node.colorStops) + ')';
+    },
+
+    visit_literal: function(node) {
+      return node.value;
+    },
+
+    visit_array: function(elements) {
+      var result = '',
+          size = elements.length;
+
+      elements.forEach(function(element, i) {
+        result += visitor.visit(element);
+        if (i < size - 1) {
+          result += ', ';
+        }
+      });
+
+      return result;
+    },
+
+    visit: function(element) {
+      if (!element) {
+        return '';
+      }
+
+      if (element instanceof Array) {
+        return visitor.visit_array(element, result);
+      } else if (element.type) {
+        var nodeVisitor = visitor['visit_' + element.type];
+        if (nodeVisitor) {
+          return nodeVisitor(element);
+        } else {
+          throw Error('Missing visitor visit_' + element.type);
+        }
+      } else {
+        throw Error('Invalid node.');
+      }
+    }
+
+  };
+
+  return function(root) {
+    return visitor.visit(root);
+  };
+})();
+
+// Copyright (c) 2014 Rafael Caricio. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+var GradientParser = (GradientParser || {});
 
 GradientParser.parse = (function() {
 
@@ -336,4 +399,5 @@ GradientParser.parse = (function() {
   };
 })();
 
-exports.parse = (GradientParser || {}).parse;
+exports.parse = GradientParser.parse;
+exports.stringify = GradientParser.stringify;

build/web.js

@@ -1,8 +1,10 @@
+var GradientParser = (window.GradientParser || {});
+
 // Copyright (c) 2014 Rafael Caricio. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-var GradientParser = {};
+var GradientParser = (GradientParser || {});
 
 GradientParser.parse = (function() {
 
@@ -335,3 +337,66 @@ GradientParser.parse = (function() {
     return getAST();
   };
 })();
+
+// Copyright (c) 2014 Rafael Caricio. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+var GradientParser = (GradientParser || {});
+
+GradientParser.stringify = (function() {
+
+  var visitor = {
+
+    'visit_linear-gradient': function(node) {
+      var orientation = visitor.visit(node.orientation);
+      if (orientation) {
+        orientation += ', ';
+      }
+
+      return 'linear-gradient('+ orientation + visitor.visit(node.colorStops) + ')';
+    },
+
+    visit_literal: function(node) {
+      return node.value;
+    },
+
+    visit_array: function(elements) {
+      var result = '',
+          size = elements.length;
+
+      elements.forEach(function(element, i) {
+        result += visitor.visit(element);
+        if (i < size - 1) {
+          result += ', ';
+        }
+      });
+
+      return result;
+    },
+
+    visit: function(element) {
+      if (!element) {
+        return '';
+      }
+
+      if (element instanceof Array) {
+        return visitor.visit_array(element, result);
+      } else if (element.type) {
+        var nodeVisitor = visitor['visit_' + element.type];
+        if (nodeVisitor) {
+          return nodeVisitor(element);
+        } else {
+          throw Error('Missing visitor visit_' + element.type);
+        }
+      } else {
+        throw Error('Invalid node.');
+      }
+    }
+
+  };
+
+  return function(root) {
+    return visitor.visit(root);
+  };
+})();

gruntfile.js

@@ -19,8 +19,8 @@ module.exports = function (grunt) {
     concat: {
       release: {
         files: {
-          'build/node.js': ['lib/parser.js', 'index.js'],
-          'build/web.js': ['lib/parser.js']
+          'build/node.js': ['lib/stringify.js', 'lib/parser.js', 'index.js'],
+          'build/web.js': ['webify.js', 'lib/parser.js', 'lib/stringify.js']
         }
       }
     }

index.js

@@ -1 +1,2 @@
-exports.parse = (GradientParser || {}).parse;
+exports.parse = GradientParser.parse;
+exports.stringify = GradientParser.stringify;

lib/parser.js

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-var GradientParser = {};
+var GradientParser = (GradientParser || {});
 
 GradientParser.parse = (function() {
 

lib/stringify.js

@@ -0,0 +1,62 @@
+// Copyright (c) 2014 Rafael Caricio. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+var GradientParser = (GradientParser || {});
+
+GradientParser.stringify = (function() {
+
+  var visitor = {
+
+    'visit_linear-gradient': function(node) {
+      var orientation = visitor.visit(node.orientation);
+      if (orientation) {
+        orientation += ', ';
+      }
+
+      return 'linear-gradient('+ orientation + visitor.visit(node.colorStops) + ')';
+    },
+
+    visit_literal: function(node) {
+      return node.value;
+    },
+
+    visit_array: function(elements) {
+      var result = '',
+          size = elements.length;
+
+      elements.forEach(function(element, i) {
+        result += visitor.visit(element);
+        if (i < size - 1) {
+          result += ', ';
+        }
+      });
+
+      return result;
+    },
+
+    visit: function(element) {
+      if (!element) {
+        return '';
+      }
+
+      if (element instanceof Array) {
+        return visitor.visit_array(element, result);
+      } else if (element.type) {
+        var nodeVisitor = visitor['visit_' + element.type];
+        if (nodeVisitor) {
+          return nodeVisitor(element);
+        } else {
+          throw Error('Missing visitor visit_' + element.type);
+        }
+      } else {
+        throw Error('Invalid node.');
+      }
+    }
+
+  };
+
+  return function(root) {
+    return visitor.visit(root);
+  };
+})();

spec/parser.spec.js

@@ -4,7 +4,7 @@ var expect = require('expect.js');
 var gradients = require('build/node');
 
 
-describe('gradient-parser.js', function () {
+describe('lib/parser.js', function () {
   var ast,
     subject;
 

spec/stringify.spec.js

@@ -0,0 +1,26 @@
+'use strict';
+
+var expect = require('expect.js');
+var gradients = require('build/node');
+
+describe('lib/stringify.js', function () {
+  var subject;
+
+  it('should exist', function () {
+    expect(typeof gradients.stringify).to.equal('function');
+  });
+
+  describe('serialization', function() {
+
+    it('if tree is null', function() {
+      expect(gradients.stringify(null)).to.equal('');
+    });
+
+    it('should serialize a simple gradient', function() {
+      var gradientDef = 'linear-gradient(black, white)';
+      expect(gradients.stringify(gradients.parse(gradientDef))).to.equal(gradientDef);
+    });
+
+  });
+
+});

webify.js

@@ -0,0 +1 @@
+var GradientParser = (window.GradientParser || {});