Implement type cast in the VM.

tests/language/type_cast_vm_test.dart

Index: tests/language/type_cast_vm_test.dart
===================================================================
--- tests/language/type_cast_vm_test.dart	(revision 0)
+++ tests/language/type_cast_vm_test.dart	(revision 0)
@@ -0,0 +1,158 @@
+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+//
+// Dart test program testing type casts.
+
+class TypeTest {
+  static test() {
+    int result = 0;
+    try {
+      var i = "hello" as int;  // Throws a CastException
+    } catch (TypeError error) {
+      result = 1;
+      Expect.isTrue(error is CastException);
+      Expect.equals("int", error.dstType);
+      Expect.equals("OneByteString", error.srcType);
+      Expect.equals("type cast", error.dstName);
+      int pos = error.url.lastIndexOf("/", error.url.length);
+      if (pos == -1) {
+        pos = error.url.lastIndexOf("\\", error.url.length);
+      }
+      String subs = error.url.substring(pos + 1, error.url.length);
+      Expect.equals("type_cast_vm_test.dart", subs);
+      Expect.equals(11, error.line);
+      Expect.equals(23, error.column);
+    }
+    return result;
+  }
+
+  static testSideEffect() {
+    int result = 0;
+    int index() {
+      result++;
+      return 0;
+    }
+    try {
+      var a = new List<int>(1) as List<int>;
+      a[0] = 0;
+      a[index()]++;  // Type check succeeds, but does not create side effects.
+      assert(a[0] == 1);
+    } catch (TypeError error) {
+      result = 100;
+    }
+    return result;
+  }
+
+  static testArgument() {
+    int result = 0;
+    int f(int i) {
+      return i;
+    }
+    try {
+      int i = f("hello" as int);  // Throws a CastException
+    } catch (TypeError error) {
+      result = 1;
+      Expect.isTrue(error is CastException);
+      Expect.equals("int", error.dstType);
+      Expect.equals("OneByteString", error.srcType);
+      Expect.equals("type cast", error.dstName);
+      int pos = error.url.lastIndexOf("/", error.url.length);
+      if (pos == -1) {
+        pos = error.url.lastIndexOf("\\", error.url.length);
+      }
+      String subs = error.url.substring(pos + 1, error.url.length);
+      Expect.equals("type_cast_vm_test.dart", subs);
+      Expect.equals(53, error.line);
+      Expect.equals(25, error.column);
+    }
+    return result;
+  }
+
+  static testReturn() {
+    int result = 0;
+    int f(String s) {
+      return s as int;  // Throws a CastException
+    }
+    try {
+      int i = f("hello");
+    } catch (TypeError error) {
+      result = 1;
+      Expect.isTrue(error is CastException);
+      Expect.equals("int", error.dstType);
+      Expect.equals("OneByteString", error.srcType);
+      Expect.equals("type cast", error.dstName);
+      int pos = error.url.lastIndexOf("/", error.url.length);
+      if (pos == -1) {
+        pos = error.url.lastIndexOf("\\", error.url.length);
+      }
+      String subs = error.url.substring(pos + 1, error.url.length);
+      Expect.equals("type_cast_vm_test.dart", subs);
+      Expect.equals(75, error.line);
+      Expect.equals(16, error.column);
+    }
+    return result;
+  }
+
+  static var field = "hello";
+  static testField() {
+    int result = 0;
+    Expect.equals(5, (field as String).length);
+    try {
+      field as int;  // Throws a CastException
+    } catch (TypeError error) {
+      result = 1;
+      Expect.equals("int", error.dstType);
+      Expect.equals("OneByteString", error.srcType);
+      Expect.equals("type cast", error.dstName);
+      int pos = error.url.lastIndexOf("/", error.url.length);
+      if (pos == -1) {
+        pos = error.url.lastIndexOf("\\", error.url.length);
+      }
+      String subs = error.url.substring(pos + 1, error.url.length);
+      Expect.equals("type_cast_vm_test.dart", subs);
+      Expect.equals(102, error.line);
+      Expect.equals(13, error.column);
+    }
+    return result;
+  }
+
+  static testAnyFunction() {
+    int result = 0;
+    Function anyFunction;
+    f() { };
+    anyFunction = f as Function;  // No error.
+    anyFunction = null as Function;  // No error.
+    try {
+      var i = f as int;  // Throws a TypeError if type checks are enabled.
+    } catch (TypeError error) {
+      result = 1;
+      Expect.equals("int", error.dstType);
+      Expect.equals("() => Dynamic", error.srcType);
+      Expect.equals("type cast", error.dstName);
+      int pos = error.url.lastIndexOf("/", error.url.length);
+      if (pos == -1) {
+        pos = error.url.lastIndexOf("\\", error.url.length);
+      }
+      String subs = error.url.substring(pos + 1, error.url.length);
+      Expect.equals("type_cast_vm_test.dart", subs);
+      Expect.equals(127, error.line);
+      Expect.equals(17, error.column);
+    }
+    return result;
+  }
+
+  static testMain() {
+    Expect.equals(1, test());
+    Expect.equals(1, testSideEffect());
+    Expect.equals(1, testArgument());
+    Expect.equals(1, testReturn());
+    Expect.equals(1, testField());
+    Expect.equals(1, testAnyFunction());
+  }
+}
+
+
+main() {
+  TypeTest.testMain();
+}