Add a library for manipulating stack traces.

pkg/stack_trace/test/frame_test.dart

+// Copyright (c) 2013, 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.
+
+library frame_test;
+
+import 'dart:uri';
+
+import 'package:pathos/path.dart' as path;
+import 'package:stack_trace/stack_trace.dart';
+import 'package:unittest/unittest.dart';
+
+String getStackFrame() {
+  try {
+    throw '';
+  } catch (_, stackTrace) {
+    return stackTrace.toString().split("\n").first;
+  }
+}
+
+Frame getCaller([int level]) {
+  if (level == null) return new Frame.caller();
+  return new Frame.caller(level);
+}
+
+Frame nestedGetCaller(int level) => getCaller(level);
+
+void main() {
+  test('parses a stack frame correctly', () {
+    var frame = new Frame.parse("#1      Foo._bar "
+        "(file:///home/nweiz/code/stuff.dart:42:21)");
+    expect(frame.uri,
+        equals(new Uri.fromString("file:///home/nweiz/code/stuff.dart")));
+    expect(frame.line, equals(42));
+    expect(frame.column, equals(21));
+    expect(frame.member, equals('Foo._bar'));
+  });
+
+  test('parses a real stack frame correctly', () {
+    var frame = new Frame.parse(getStackFrame());
+    // TODO(nweiz): use URL-style paths when such a thing exists.
+    var builder = new path.Builder(style: path.Style.posix);
+    expect(builder.basename(frame.uri.path), equals('frame_test.dart'));
+    expect(frame.line, equals(15));
+    expect(frame.column, equals(5));
+    expect(frame.member, equals('getStackFrame'));
+  });
+
+  test('converts "<anonymous closure>" to "<fn>"', () {
+    String parsedMember(String member) =>
+        new Frame.parse('#0 $member (foo:0:0)').member;
+
+    expect(parsedMember('Foo.<anonymous closure>'), equals('Foo.<fn>'));
+    expect(parsedMember('<anonymous closure>.<anonymous closure>.bar'),
+        equals('<fn>.<fn>.bar'));
+  });
+
+  test('throws a FormatException for malformed frames', () {
+    expect(() => new Frame.parse(''), throwsFormatException);
+    expect(() => new Frame.parse('#1'), throwsFormatException);
+    expect(() => new Frame.parse('#1      Foo'), throwsFormatException);
+    expect(() => new Frame.parse('#1      Foo (dart:async)'),
+        throwsFormatException);
+    expect(() => new Frame.parse('#1      Foo (dart:async:10)'),
+        throwsFormatException);
+    expect(() => new Frame.parse('#1      (dart:async:10:15)'),
+        throwsFormatException);
+    expect(() => new Frame.parse('Foo (dart:async:10:15)'),
+        throwsFormatException);
+  });
+
+  test('only considers dart URIs to be core', () {
+    bool isCore(String library) =>
+      new Frame.parse('#0 Foo ($library:0:0)').isCore;
+
+    expect(isCore('dart:core'), isTrue);
+    expect(isCore('dart:async'), isTrue);
+    expect(isCore('bart:core'), isFalse);
+    expect(isCore('sdart:core'), isFalse);
+    expect(isCore('darty:core'), isFalse);
+  });
+
+  group('.caller()', () {
+    test('with no argument returns the parent frame', () {
+      expect(getCaller().member, equals('main.<fn>.<fn>'));
+    });
+
+    test('at level 0 returns the current frame', () {
+      expect(getCaller(0).member, equals('getCaller'));
+    });
+
+    test('at level 1 returns the current frame', () {
+      expect(getCaller(1).member, equals('main.<fn>.<fn>'));
+    });
+
+    test('at level 2 returns the grandparent frame', () {
+      expect(nestedGetCaller(2).member, equals('main.<fn>.<fn>'));
+    });
+
+    test('throws an ArgumentError for negative levels', () {
+      expect(() => new Frame.caller(-1), throwsArgumentError);
+    });
+  });
+
+  group('.library', () {
+    test('returns the URI string for non-file URIs', () {
+      expect(new Frame.parse('#0 Foo (dart:async:0:0)').library,
+          equals('dart:async'));
+      expect(new Frame.parse('#0 Foo '
+              '(http://dartlang.org/stuff/thing.dart:0:0)').library,
+          equals('http://dartlang.org/stuff/thing.dart'));
+    });
+
+    test('returns the relative path for file URIs', () {
+      var absolute = path.absolute(path.join('foo', 'bar.dart'));
+      expect(new Frame.parse('#0 Foo (file://$absolute:0:0)').library,
+          equals(path.join('foo', 'bar.dart')));
+    });
+  });
+
+  group('.location', () {
+    test('returns the library and line/column numbers for non-core '
+        'libraries', () {
+      expect(new Frame.parse('#0 Foo '
+              '(http://dartlang.org/thing.dart:5:10)').location,
+          equals('http://dartlang.org/thing.dart 5:10'));
+      var absolute = path.absolute(path.join('foo', 'bar.dart'));
+      expect(new Frame.parse('#0 Foo (file://$absolute:1:2)').location,
+          equals('${path.join('foo', 'bar.dart')} 1:2'));
+    });
+
+    test('just returns the library for core libraries', () {
+      expect(new Frame.parse('#0 Foo (dart:core:5:10)').location,
+          equals('dart:core'));
+      expect(new Frame.parse('#0 Foo (dart:async-patch:1:2)').location,
+          equals('dart:async-patch'));
+    });
+  });
+
+  group('.toString()', () {
+    test('returns the library and line/column numbers for non-core '
+        'libraries', () {
+      expect(new Frame.parse('#0 Foo (http://dartlang.org/thing.dart:5:10)')
+              .toString(),
+          equals('http://dartlang.org/thing.dart 5:10 in Foo'));
+    });
+
+    test('just returns the library for core libraries', () {
+      expect(new Frame.parse('#0 Foo (dart:core:5:10)').toString(),
+          equals('dart:core in Foo'));
+    });
+
+    test('converts "<anonymous closure>" to "<fn>"', () {
+      expect(new Frame.parse('#0 Foo.<anonymous closure> (dart:core:5:10)')
+              .toString(),
+          equals('dart:core in Foo.<fn>'));
+    });
+  });
+}