Better messages for optimized index errors.

tests/compiler/dart2js_extra/consistent_index_error_string_test.dart

+// Copyright (c) 2015, 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.
+
+import "package:expect/expect.dart";
+import "dart:typed_data";
+
+// Test that optimized indexing and slow path indexing produce the same error.
+
+@NoInline()
+@AssumeDynamic()
+confuse(x) => x;
+
+class TooHigh {
+  static load1() {
+    var a = confuse(true) ? 'AB' : 'ABCDE';
+    try {
+      return confuse(a)[3];  // dynamic receiver for indexer.
+    } catch (e) {
+      return e;
+    }
+    Expect.fail('unreached');
+  }
+
+  static load2() {
+    try {
+      confuse(load2x)(3);
+    } catch (e) {
+      return e;
+    }
+    Expect.fail('unreached');
+  }
+  static load2x(i) {
+    var a = confuse(true) ? 'AB' : 'ABCDE';
+    return a[i];  // 'a' is String of unknown length.
+  }
+
+  static test() {
+    var e1 = load1();
+    var e2 = load2();
+    print("  A: '$e1'\n  B: '$e2'");
+    Expect.equals('$e1', '$e2');
+  }
+}
+
+class Negative {
+  static load1() {
+    var a = confuse(true) ? 'AB' : 'ABCDE';
+    try {
+      return confuse(a)[-3];  // dynamic receiver for indexer.
+    } catch (e) {
+      return e;
+    }
+    Expect.fail('unreached');
+  }
+
+  static load2() {
+    try {
+      confuse(load2x)(-3);
+    } catch (e) {
+      return e;
+    }
+    Expect.fail('unreached');
+  }
+  static load2x(i) {
+    var a = confuse(true) ? 'AB' : 'ABCDE';
+    return a[i];  // 'a' is String of unknown length.
+  }
+
+  static test() {
+    var e1 = load1();
+    var e2 = load2();
+    print("  A: '$e1'\n  B: '$e2'");
+    Expect.equals('$e1', '$e2');
+  }
+}
+
+class Empty {
+  static load1() {
+    var a = confuse(true) ? '' : 'ABCDE';
+    try {
+      return confuse(a)[-3];  // dynamic receiver for indexer.
+    } catch (e) {
+      return e;
+    }
+    Expect.fail('unreached');
+  }
+
+  static load2() {
+    try {
+      confuse(load2x)(-3);
+    } catch (e) {
+      return e;
+    }
+    Expect.fail('unreached');
+  }
+  static load2x(i) {
+    var a = confuse(true) ? '' : 'ABCDE';
+    return a[i];  // 'a' is String of unknown length.
+  }
+
+  static test() {
+    var e1 = load1();
+    var e2 = load2();
+    print("  A: '$e1'\n  B: '$e2'");
+    Expect.equals('$e1', '$e2');
+  }
+}
+
+class BadType {
+  static load1() {
+    var a = confuse(true) ? 'AB' : 'ABCDE';
+    try {
+      return confuse(a)['a'];  // dynamic receiver for indexer.
+    } catch (e) {
+      return e;
+    }
+    Expect.fail('unreached');
+  }
+
+  static load2() {
+    try {
+      confuse(load2x)('a');
+    } catch (e) {
+      return e;
+    }
+    Expect.fail('unreached');
+  }
+  static load2x(i) {
+    var a = confuse(true) ? 'AB' : 'ABCDE';
+    return a[i];  // 'a' is String of unknown length.
+  }
+
+  static test() {
+    var e1 = load1();
+    var e2 = load2();
+    print("  A: '$e1'\n  B: '$e2'");
+    Expect.equals('$e1', '$e2');
+  }
+}
+
+main() {
+  TooHigh.test();
+  Negative.test();
+  Empty.test();
+  BadType.test();
+}