Add observatory_pub_packages snapshot to third_party

observatory_pub_packages/matcher/src/operator_matchers.dart

+// 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.
+
+library matcher.operator_matchers;
+
+import 'interfaces.dart';
+import 'util.dart';
+
+/// This returns a matcher that inverts [matcher] to its logical negation.
+Matcher isNot(matcher) => new _IsNot(wrapMatcher(matcher));
+
+class _IsNot extends Matcher {
+  final Matcher _matcher;
+
+  const _IsNot(this._matcher);
+
+  bool matches(item, Map matchState) => !_matcher.matches(item, matchState);
+
+  Description describe(Description description) =>
+    description.add('not ').addDescriptionOf(_matcher);
+}
+
+/// This returns a matcher that matches if all of the matchers passed as
+/// arguments (up to 7) match.
+///
+/// Instead of passing the matchers separately they can be passed as a single
+/// List argument. Any argument that is not a matcher is implicitly wrapped in a
+/// Matcher to check for equality.
+Matcher allOf(arg0,
+             [arg1 = null,
+              arg2 = null,
+              arg3 = null,
+              arg4 = null,
+              arg5 = null,
+              arg6 = null]) {
+  return new _AllOf(_wrapArgs(arg0, arg1, arg2, arg3, arg4, arg5, arg6));
+}
+
+class _AllOf extends Matcher {
+  final List<Matcher> _matchers;
+
+  const _AllOf(this._matchers);
+
+  bool matches(item, Map matchState) {
+     for (var matcher in _matchers) {
+       if (!matcher.matches(item, matchState)) {
+        addStateInfo(matchState, {'matcher': matcher});
+         return false;
+       }
+     }
+     return true;
+  }
+
+  Description describeMismatch(item, Description mismatchDescription,
+                               Map matchState, bool verbose) {
+    var matcher = matchState['matcher'];
+    matcher.describeMismatch(item, mismatchDescription,
+        matchState['state'], verbose);
+    return mismatchDescription;
+  }
+
+  Description describe(Description description) =>
+      description.addAll('(', ' and ', ')', _matchers);
+}
+
+/// Matches if any of the given matchers evaluate to true.
+///
+/// The arguments can be a set of matchers as separate parameters
+/// (up to 7), or a List of matchers.
+///
+/// The matchers are evaluated from left to right using short-circuit
+/// evaluation, so evaluation stops as soon as a matcher returns true.
+///
+/// Any argument that is not a matcher is implicitly wrapped in a
+/// Matcher to check for equality.
+Matcher anyOf(arg0,
+               [arg1 = null,
+                arg2 = null,
+                arg3 = null,
+                arg4 = null,
+                arg5 = null,
+                arg6 = null]) {
+  return new _AnyOf(_wrapArgs(arg0, arg1, arg2, arg3, arg4, arg5, arg6));
+}
+
+class _AnyOf extends Matcher {
+  final List<Matcher> _matchers;
+
+  const _AnyOf(this._matchers);
+
+  bool matches(item, Map matchState) {
+    for (var matcher in _matchers) {
+      if (matcher.matches(item, matchState)) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  Description describe(Description description) =>
+    description.addAll('(', ' or ', ')', _matchers);
+}
+
+List<Matcher> _wrapArgs(arg0, arg1, arg2, arg3, arg4, arg5, arg6) {
+  Iterable<Matcher> matchers;
+  if (arg0 is List) {
+    if (arg1 != null || arg2 != null || arg3 != null || arg4 != null ||
+        arg5 != null || arg6 != null) {
+      throw new ArgumentError('If arg0 is a List, all other arguments must be'
+          ' null.');
+    }
+
+    matchers = arg0;
+  } else {
+    matchers = [arg0, arg1, arg2, arg3, arg4, arg5, arg6]
+        .where((e) => e != null);
+  }
+
+  return matchers
+      .map((e) => wrapMatcher(e))
+      .toList();
+}