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packages/petitparser/test/test_test.dart

+library petitparser.test.test_test;
+
+import 'package:test/test.dart';
+
+import 'package:petitparser/petitparser.dart';
+import 'package:petitparser/test.dart';
+
+void main() {
+  group('accept', () {
+    test('success', () {
+      var matcher = accept(char('a'));
+      var state = new Map();
+      expect(matcher.matches('a', state), isTrue);
+      expect(state, isEmpty);
+      var description = new StringDescription();
+      matcher.describe(description);
+      expect(description.toString(), '"Instance of \'CharacterParser\'["a" expected]" accepts input');
+    });
+    test('failure', () {
+      var matcher = accept(char('a'));
+      var state = new Map();
+      expect(matcher.matches('b', state), isFalse);
+      expect(state, isNot(isEmpty));
+      var description = new StringDescription();
+      matcher.describeMismatch('b', description, state, false);
+      expect(description.toString(), '"Instance of \'CharacterParser\'["a" expected]" produces "Failure[1:1]: "a" expected" which is not accepted');
+    });
+  });
+  group('parse', () {
+    test('success', () {
+      var matcher = parse(char('a'), 'a');
+      var state = new Map();
+      expect(matcher.matches('a', state), isTrue);
+      expect(state, isEmpty);
+      var description = new StringDescription();
+      matcher.describe(description);
+      expect(description.toString(), '"Instance of \'CharacterParser\'["a" expected]" '
+          'accepts \'a\'');
+    });
+    test('failure', () {
+      var matcher = parse(char('a'), 'a');
+      var state = new Map();
+      expect(matcher.matches('b', state), isFalse);
+      expect(state, isNot(isEmpty));
+      var description = new StringDescription();
+      matcher.describeMismatch('b', description, state, false);
+      expect(description.toString(), '"Instance of \'CharacterParser\'["a" expected]" '
+          'produces "Failure[1:1]: "a" expected" which is not accepted');
+    });
+    test('matcher', () {
+      var matcher = parse(char('a'), 'b');
+      var state = new Map();
+      expect(matcher.matches('a', state), isFalse);
+      expect(state, isNot(isEmpty));
+      var description = new StringDescription();
+      matcher.describeMismatch('a', description, state, false);
+      expect(description.toString(), '"Instance of \'CharacterParser\'["a" expected]" '
+          'produces "Success[1:2]: a" which parse result is different.\n'
+          'Expected: b\n  Actual: a\n          ^\n Differ at offset 0');
+    });
+    test('position', () {
+      var matcher = parse(char('a'), 'a', 0);
+      var state = new Map();
+      expect(matcher.matches('a', state), isFalse);
+      expect(state, isNot(isEmpty));
+      var description = new StringDescription();
+      matcher.describeMismatch('a', description, state, false);
+      expect(description.toString(), '"Instance of \'CharacterParser\'["a" expected]" '
+      'produces "Success[1:2]: a" that consumes input to 1 instead of 0');
+    });
+  });
+}