Add SliceMatcher type to objmatcher package (#118)

objmatcher/matcher.go

@@ -78,6 +78,29 @@ func (m RegExpMatcher) String() string {
 	return fmt.Sprintf("matchesRegexp(%s)", m.WantRegexp)
 }
 
+type SliceMatcher []Matcher
+
+func (s SliceMatcher) Matches(in interface{}) error {
+	items := reflect.ValueOf(in)
+	switch items.Kind() {
+	case reflect.Slice, reflect.Array:
+		break
+	default:
+		return fmt.Errorf("kind of %v is not a slice or array", in)
+	}
+
+	if len(s) != items.Len() {
+		return fmt.Errorf("want: %+v\ngot:  %+v\nsize %d != %d", s, in, len(s), items.Len())
+	}
+	for i := 0; i < items.Len(); i++ {
+		if err := s[i].Matches(items.Index(i).Interface()); err != nil {
+			indented := strings.Replace("\n"+err.Error(), "\n", "\n\t", -1)
+			return fmt.Errorf("want: %+v\ngot:  %+v\nvalue for index %d did not match:%s", s, in, i, indented)
+		}
+	}
+	return nil
+}
+
 type MapMatcher map[string]Matcher
 
 func (m MapMatcher) Matches(in interface{}) error {

objmatcher/matcher_test.go

@@ -92,3 +92,66 @@ func TestEqualsMatcher(t *testing.T) {
 		}
 	}
 }
+
+func TestMapMatcher(t *testing.T) {
+	for i, tc := range []struct {
+		name    string
+		matcher objmatcher.MapMatcher
+		given   interface{}
+		wantErr string
+	}{
+		{
+			name: "map matches",
+			matcher: objmatcher.MapMatcher(map[string]objmatcher.Matcher{
+				"key": objmatcher.NewEqualsMatcher("value"),
+			}),
+			given: map[string]interface{}{
+				"key": "value",
+			},
+		},
+	} {
+		gotErr := tc.matcher.Matches(tc.given)
+		if tc.wantErr == "" {
+			assert.NoError(t, gotErr, "Case %d: %v", i, tc.name)
+		} else {
+			assert.EqualError(t, gotErr, tc.wantErr, "Case %d: %v", i, tc.name)
+		}
+	}
+}
+
+func TestSliceMatcher(t *testing.T) {
+	for i, tc := range []struct {
+		name    string
+		matcher objmatcher.SliceMatcher
+		given   interface{}
+		wantErr string
+	}{
+		{
+			name: "strings slice matches",
+			matcher: objmatcher.SliceMatcher([]objmatcher.Matcher{
+				objmatcher.NewEqualsMatcher("hello"),
+			}),
+			given: []string{
+				"hello",
+			},
+		},
+		{
+			name: "unequal slice length fails",
+			matcher: objmatcher.SliceMatcher([]objmatcher.Matcher{
+				objmatcher.NewEqualsMatcher("hello"),
+			}),
+			given: []string{
+				"hello",
+				"goodbye",
+			},
+			wantErr: "want: [equals(string(hello))]\ngot:  [hello goodbye]\nsize 1 != 2",
+		},
+	} {
+		gotErr := tc.matcher.Matches(tc.given)
+		if tc.wantErr == "" {
+			assert.NoError(t, gotErr, "Case %d: %v", i, tc.name)
+		} else {
+			assert.EqualError(t, gotErr, tc.wantErr, "Case %d: %v", i, tc.name)
+		}
+	}
+}