typeof operator

alongubkin · Nov 14, 2014 · 24e4a58 · 24e4a58
1 parent 06460e6
commit 24e4a58
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Showing 4 changed files with 815 additions and 642 deletions.
diff --git a/lib/ast/expressions/UnaryExpression.js b/lib/ast/expressions/UnaryExpression.js
@@ -18,9 +18,121 @@ exports.UnaryExpression.prototype.codegen = function () {
   }
 
   this.argument = this.argument.codegen();
+
+  // typeof operator should compile to:
+  // ({}).toString.call(obj).match(/\s([a-zA-Z]+)/)[1].toLowerCase()
+  if (this.operator === 'typeof') {    
+    var typeofExpression = {
+      "type": "CallExpression",
+      "callee": {
+        "type": "MemberExpression",
+        "computed": false,
+        "object": {
+          "type": "MemberExpression",
+          "computed": true,
+          "object": {
+            "type": "CallExpression",
+            "callee": {
+              "type": "MemberExpression",
+              "computed": false,
+              "object": {
+                "type": "CallExpression",
+                "callee": {
+                  "type": "MemberExpression",
+                  "computed": false,
+                  "object": {
+                    "type": "MemberExpression",
+                    "computed": false,
+                    "object": {
+                      "type": "ObjectExpression",
+                      "properties": []
+                    },
+                    "property": {
+                      "type": "Identifier",
+                      "name": "toString"
+                    }
+                  },
+                  "property": {
+                    "type": "Identifier",
+                    "name": "call"
+                  }
+                },
+                "arguments": [this.argument]
+              },
+              "property": {
+                "type": "Identifier",
+                "name": "match"
+              }
+            },
+            "arguments": [{
+              "type": "Literal",
+              "value": "/\\s([a-zA-Z]+)/",
+              "raw": "/\\s([a-zA-Z]+)/"
+            }]
+          },
+          "property": {
+            "type": "Literal",
+            "value": 1,
+            "raw": "1"
+          }
+        },
+        "property": {
+          "type": "Identifier",
+          "name": "toLowerCase"
+        }
+      },
+      "arguments": []
+    };
+
+    if (!this.argument.hasCallExpression()) {
+      this.type = "ConditionalExpression";
+      this.test = {
+        "type": "BinaryExpression",
+        "operator": "===",
+        "left": {
+          "type": "UnaryExpression",
+          "operator": "typeof",
+          "argument": this.argument,
+          "prefix": true
+        },
+        "right": {
+          "type": "Literal",
+          "value": "undefined",
+          "raw": "'undefined'"
+        }
+      };
+
+      this.consequent = {
+        "type": "Literal",
+        "value": "undefined"
+      };
+
+      this.alternate = typeofExpression;
+    } else {
+      this.type = typeofExpression.type;
+      this.callee = typeofExpression.callee;
+      Object.defineProperty(this, 'arguments', { 
+        value: typeofExpression.arguments, 
+        enumerable: true 
+      });
+    }
+  }
+
   return this;
 };
 
 exports.UnaryExpression.prototype.hasCallExpression = function () {
   return (this.argument !== null && this.argument.hasCallExpression());
+};
+
+exports.UnaryExpression.getNextVariableName = function () {
+  if (!this.unaryExpressionIndex) { 
+    this.unaryExpressionIndex = 0; 
+  }
+
+  return "unaryExpression" + this.unaryExpressionIndex++;
+};
+
+exports.UnaryExpression.resetVariableNames = function () {
+  this.unaryExpressionIndex = 0;
 };