Cast boolean and null before creating literal expression

src/ol/expression/parser.js

@@ -404,10 +404,14 @@ ol.expression.Parser.prototype.parsePrimaryExpression_ = function(lexer) {
   if (type === ol.expression.TokenType.IDENTIFIER) {
     expr = this.createIdentifier_(/** @type {string} */ (token.value));
   } else if (type === ol.expression.TokenType.STRING_LITERAL ||
-      type === ol.expression.TokenType.NUMERIC_LITERAL ||
-      type === ol.expression.TokenType.BOOLEAN_LITERAL ||
-      type === ol.expression.TokenType.NULL_LITERAL) {
+      type === ol.expression.TokenType.NUMERIC_LITERAL) {
+    // numeric and string literals are already the correct type
     expr = this.createLiteral_(token.value);
+  } else if (type === ol.expression.TokenType.BOOLEAN_LITERAL) {
+    // because booleans are valid member properties, tokens are still string
+    expr = this.createLiteral_(token.value === 'true');
+  } else if (type === ol.expression.TokenType.NULL_LITERAL) {
+    expr = this.createLiteral_(null);
   } else {
     throw new Error('Unexpected token: ' + token.value);
   }

test/spec/ol/expression/parser.test.js

@@ -1,4 +1,4 @@
-goog.provide('ol.test.expression');
+goog.provide('ol.test.expression.Parser');
 
 describe('ol.expression.Parser', function() {
 
@@ -19,13 +19,47 @@ describe('ol.expression.Parser', function() {
 
     it('parses grouped expressions', function() {
       var expr = parse('(3 * (foo + 2))');
-      expect(expr).to.be.a(ol.expression.Expression);
       expect(expr).to.be.a(ol.expression.Math);
       expect(expr.evaluate({foo: 3})).to.be(15);
     });
 
   });
 
+  describe('#parsePrimaryExpression_()', function() {
+
+    function parse(source) {
+      var lexer = new ol.expression.Lexer(source);
+      var parser = new ol.expression.Parser();
+      return parser.parsePrimaryExpression_(lexer);
+    }
+
+    it('parses string literal', function() {
+      var expr = parse('"foo"');
+      expect(expr).to.be.a(ol.expression.Literal);
+      expect(expr.evaluate({})).to.be('foo');
+    });
+
+    it('parses numeric literal', function() {
+      var expr = parse('.42e2');
+      expect(expr).to.be.a(ol.expression.Literal);
+      expect(expr.evaluate({})).to.be(42);
+    });
+
+    it('parses boolean literal', function() {
+      var expr = parse('.42e2');
+      expect(expr).to.be.a(ol.expression.Literal);
+      expect(expr.evaluate({})).to.be(42);
+    });
+
+    it('parses null literal', function() {
+      var expr = parse('null');
+      expect(expr).to.be.a(ol.expression.Literal);
+      expect(expr.evaluate({})).to.be(null);
+    });
+
+  });
+
+
 });