Allow set tag to use bracket notation for object properties

lib/tags/set.js

@@ -14,6 +14,13 @@
  * {% set bar += index|default(3) %}
  * // => 3
  *
+ * @example
+ * // foods = {};
+ * // food = 'chili';
+ * {% set foods[food] = "con queso" %}
+ * {{ foods.chili }}
+ * // => con queso
+ *
  * @param {literal} varname   The variable name to assign the value to.
  * @param {literal} assignement   Any valid JavaScript assignement. <code data-language="js">=, +=, *=, /=, -=</code>
  * @param {*}   value     Valid variable output.
@@ -23,25 +30,61 @@ exports.compile = function (compiler, args) {
 };
 
 exports.parse = function (str, line, parser, types) {
-  var nameSet;
+  var nameSet = '',
+    propertyName = '';
+
   parser.on(types.VAR, function (token) {
-    if (!this.out.length) {
-      nameSet = token.match;
-      this.out.push(
-        // Prevent the set from spilling into global scope
-        '_ctx.' + nameSet
-      );
+    if (propertyName) {
+      // Tell the parser where to find the variable
+      propertyName += '_ctx.' + token.match;
+      return;
+    }
+
+    if (!parser.out.length) {
+      nameSet += token.match;
+      return;
+    }
+
+    return true;
+  });
+
+  parser.on(types.BRACKETOPEN, function (token) {
+    if (!propertyName && !this.out.length) {
+      propertyName = token.match;
+      return;
+    }
+
+    return true;
+  });
+
+  parser.on(types.STRING, function (token) {
+    if (propertyName && !this.out.length) {
+      propertyName += token.match;
+      return;
+    }
+
+    return true;
+  });
+
+  parser.on(types.BRACKETCLOSE, function (token) {
+    if (propertyName && !this.out.length) {
+      nameSet += propertyName + token.match;
+      propertyName = '';
       return;
     }
 
     return true;
   });
 
   parser.on(types.ASSIGNMENT, function (token) {
-    if (this.out.length !== 1 || !nameSet) {
+    if (this.out.length || !nameSet) {
       throw new Error('Unexpected assignment "' + token.match + '" on line ' + line + '.');
     }
 
+    this.out.push(
+      // Prevent the set from spilling into global scope
+      '_ctx.' + nameSet
+    );
     this.out.push(token.match);
   });
 

tests/tags/set.test.js

@@ -3,7 +3,17 @@ var swig = require('../../lib/swig'),
   _ = require('lodash'),
   Swig = swig.Swig;
 
-var cases = [
+var leftCases = [
+  'foo[bar]',
+  'foo[\'bar\']',
+  'foo["bar"]',
+  'foo[\'bar.baz\']',
+  'foo["bar.baz"]',
+  'foo[\'bar=baz\']',
+  'foo["bar=baz"]'
+];
+
+var rightCases = [
   { code: '= 1', result: '1' },
   { code: '= "burritos"', result: 'burritos' },
   { code: '= 1 + 3', result: '4' },
@@ -18,7 +28,14 @@ var cases = [
 
 describe('Tag: set', function () {
 
-  _.each(cases, function (c) {
+  _.each(leftCases, function (c) {
+    var s = '{% set bar = "bar" %}{% set ' + c + ' = "con queso" %}';
+    it(s, function () {
+      expect(swig.render(s + '{{ ' + c + ' }}', { locals: { foo: {} }})).to.equal('con queso');
+    });
+  });
+
+  _.each(rightCases, function (c) {
     var s = '{% set foo ' + c.code + ' %}';
     it(s, function () {
       expect(swig.render(s + '{{ foo }}', { locals: { foo: 1 }})).to.equal(c.result);