Compare public elements of struct (#1309)

* Implement checking only exported fields

Co-authored-by: Anthony Chang <anthony-chang@users.noreply.github.com>

* Update comment

* Run go generate

* Make compatiable with Go 1.16.5

* Fix go generate files

* Fix white space changes

* Fix whitespace changes

* Fix whitespace changes in gogenerate files

---------

Co-authored-by: Anthony Chang <anthony-chang@users.noreply.github.com>

assert/assertion_format.go

@@ -90,6 +90,23 @@ func EqualErrorf(t TestingT, theError error, errString string, msg string, args
 	return EqualError(t, theError, errString, append([]interface{}{msg}, args...)...)
 }
 
+// EqualExportedValuesf asserts that the types of two objects are equal and their public
+// fields are also equal. This is useful for comparing structs that have private fields
+// that could potentially differ.
+//
+// 	 type S struct {
+// 		Exported     	int
+// 		notExported   	int
+// 	 }
+// 	 assert.EqualExportedValuesf(t, S{1, 2}, S{1, 3}, "error message %s", "formatted") => true
+// 	 assert.EqualExportedValuesf(t, S{1, 2}, S{2, 3}, "error message %s", "formatted") => false
+func EqualExportedValuesf(t TestingT, expected interface{}, actual interface{}, msg string, args ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+	return EqualExportedValues(t, expected, actual, append([]interface{}{msg}, args...)...)
+}
+
 // EqualValuesf asserts that two objects are equal or convertable to the same types
 // and equal.
 //

assert/assertion_forward.go

@@ -155,6 +155,40 @@ func (a *Assertions) EqualErrorf(theError error, errString string, msg string, a
 	return EqualErrorf(a.t, theError, errString, msg, args...)
 }
 
+// EqualExportedValues asserts that the types of two objects are equal and their public
+// fields are also equal. This is useful for comparing structs that have private fields
+// that could potentially differ.
+//
+// 	 type S struct {
+// 		Exported     	int
+// 		notExported   	int
+// 	 }
+// 	 a.EqualExportedValues(S{1, 2}, S{1, 3}) => true
+// 	 a.EqualExportedValues(S{1, 2}, S{2, 3}) => false
+func (a *Assertions) EqualExportedValues(expected interface{}, actual interface{}, msgAndArgs ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return EqualExportedValues(a.t, expected, actual, msgAndArgs...)
+}
+
+// EqualExportedValuesf asserts that the types of two objects are equal and their public
+// fields are also equal. This is useful for comparing structs that have private fields
+// that could potentially differ.
+//
+// 	 type S struct {
+// 		Exported     	int
+// 		notExported   	int
+// 	 }
+// 	 a.EqualExportedValuesf(S{1, 2}, S{1, 3}, "error message %s", "formatted") => true
+// 	 a.EqualExportedValuesf(S{1, 2}, S{2, 3}, "error message %s", "formatted") => false
+func (a *Assertions) EqualExportedValuesf(expected interface{}, actual interface{}, msg string, args ...interface{}) bool {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	return EqualExportedValuesf(a.t, expected, actual, msg, args...)
+}
+
 // EqualValues asserts that two objects are equal or convertable to the same types
 // and equal.
 //

assert/assertions.go

@@ -75,6 +75,48 @@ func ObjectsAreEqual(expected, actual interface{}) bool {
 	return bytes.Equal(exp, act)
 }
 
+// ObjectsExportedFieldsAreEqual determines if the exported (public) fields of two structs are considered equal.
+// If the two objects are not of the same type, or if either of them are not a struct, they are not considered equal.
+//
+// This function does no assertion of any kind.
+func ObjectsExportedFieldsAreEqual(expected, actual interface{}) bool {
+	if expected == nil || actual == nil {
+		return expected == actual
+	}
+
+	expectedType := reflect.TypeOf(expected)
+	actualType := reflect.TypeOf(actual)
+
+	if expectedType != actualType {
+		return false
+	}
+
+	if expectedType.Kind() != reflect.Struct || actualType.Kind() != reflect.Struct {
+		return false
+	}
+
+	expectedValue := reflect.ValueOf(expected)
+	actualValue := reflect.ValueOf(actual)
+
+	for i := 0; i < expectedType.NumField(); i++ {
+		field := expectedType.Field(i)
+		isExported := field.PkgPath == "" // should use field.IsExported() but it's not available in Go 1.16.5
+		if isExported {
+			var equal bool
+			if field.Type.Kind() == reflect.Struct {
+				equal = ObjectsExportedFieldsAreEqual(expectedValue.Field(i).Interface(), actualValue.Field(i).Interface())
+			} else {
+				equal = ObjectsAreEqualValues(expectedValue.Field(i).Interface(), actualValue.Field(i).Interface())
+			}
+
+			if !equal {
+				return false
+			}
+		}
+	}
+	return true
+}
+
 // ObjectsAreEqualValues gets whether two objects are equal, or if their
 // values are equal.
 func ObjectsAreEqualValues(expected, actual interface{}) bool {
@@ -473,6 +515,47 @@ func EqualValues(t TestingT, expected, actual interface{}, msgAndArgs ...interfa
 
 }
 
+// EqualExportedValues asserts that the types of two objects are equal and their public
+// fields are also equal. This is useful for comparing structs that have private fields
+// that could potentially differ.
+//
+//	 type S struct {
+//		Exported     	int
+//		notExported   	int
+//	 }
+//	 assert.EqualExportedValues(t, S{1, 2}, S{1, 3}) => true
+//	 assert.EqualExportedValues(t, S{1, 2}, S{2, 3}) => false
+func EqualExportedValues(t TestingT, expected, actual interface{}, msgAndArgs ...interface{}) bool {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+
+	aType := reflect.TypeOf(expected)
+	bType := reflect.TypeOf(actual)
+
+	if aType != bType {
+		return Fail(t, fmt.Sprintf("Types expected to match exactly\n\t%v != %v", aType, bType), msgAndArgs...)
+	}
+
+	if aType.Kind() != reflect.Struct {
+		return Fail(t, fmt.Sprintf("Types expected to both be struct \n\t%v != %v", aType.Kind(), reflect.Struct), msgAndArgs...)
+	}
+
+	if bType.Kind() != reflect.Struct {
+		return Fail(t, fmt.Sprintf("Types expected to both be struct \n\t%v != %v", bType.Kind(), reflect.Struct), msgAndArgs...)
+	}
+
+	if !ObjectsExportedFieldsAreEqual(expected, actual) {
+		diff := diff(expected, actual)
+		expected, actual = formatUnequalValues(expected, actual)
+		return Fail(t, fmt.Sprintf("Not equal (comparing only exported fields): \n"+
+			"expected: %s\n"+
+			"actual  : %s%s", expected, actual, diff), msgAndArgs...)
+	}
+
+	return true
+}
+
 // Exactly asserts that two objects are equal in value and type.
 //
 //    assert.Exactly(t, int32(123), int64(123))

assert/assertions_test.go

@@ -149,6 +149,51 @@ func TestObjectsAreEqual(t *testing.T) {
 
 }
 
+func TestObjectsExportedFieldsAreEqual(t *testing.T) {
+	type Nested struct {
+		Exported    interface{}
+		notExported interface{}
+	}
+
+	type S struct {
+		Exported1    interface{}
+		Exported2    Nested
+		notExported1 interface{}
+		notExported2 Nested
+	}
+
+	type S2 struct {
+		foo interface{}
+	}
+
+	cases := []struct {
+		expected interface{}
+		actual   interface{}
+		result   bool
+	}{
+		{S{1, Nested{2, 3}, 4, Nested{5, 6}}, S{1, Nested{2, 3}, 4, Nested{5, 6}}, true},
+		{S{1, Nested{2, 3}, 4, Nested{5, 6}}, S{1, Nested{2, 3}, "a", Nested{5, 6}}, true},
+		{S{1, Nested{2, 3}, 4, Nested{5, 6}}, S{1, Nested{2, 3}, 4, Nested{5, "a"}}, true},
+		{S{1, Nested{2, 3}, 4, Nested{5, 6}}, S{1, Nested{2, 3}, 4, Nested{"a", "a"}}, true},
+		{S{1, Nested{2, 3}, 4, Nested{5, 6}}, S{1, Nested{2, "a"}, 4, Nested{5, 6}}, true},
+		{S{1, Nested{2, 3}, 4, Nested{5, 6}}, S{"a", Nested{2, 3}, 4, Nested{5, 6}}, false},
+		{S{1, Nested{2, 3}, 4, Nested{5, 6}}, S{1, Nested{"a", 3}, 4, Nested{5, 6}}, false},
+		{S{1, Nested{2, 3}, 4, Nested{5, 6}}, S2{1}, false},
+		{1, S{1, Nested{2, 3}, 4, Nested{5, 6}}, false},
+	}
+
+	for _, c := range cases {
+		t.Run(fmt.Sprintf("ObjectsExportedFieldsAreEqual(%#v, %#v)", c.expected, c.actual), func(t *testing.T) {
+			res := ObjectsExportedFieldsAreEqual(c.expected, c.actual)
+
+			if res != c.result {
+				t.Errorf("ObjectsExportedFieldsAreEqual(%#v, %#v) should return %#v", c.expected, c.actual, c.result)
+			}
+
+		})
+	}
+}
+
 func TestImplements(t *testing.T) {
 
 	mockT := new(testing.T)

require/require.go

@@ -195,6 +195,46 @@ func EqualErrorf(t TestingT, theError error, errString string, msg string, args
 	t.FailNow()
 }
 
+// EqualExportedValues asserts that the types of two objects are equal and their public
+// fields are also equal. This is useful for comparing structs that have private fields
+// that could potentially differ.
+//
+// 	 type S struct {
+// 		Exported     	int
+// 		notExported   	int
+// 	 }
+// 	 assert.EqualExportedValues(t, S{1, 2}, S{1, 3}) => true
+// 	 assert.EqualExportedValues(t, S{1, 2}, S{2, 3}) => false
+func EqualExportedValues(t TestingT, expected interface{}, actual interface{}, msgAndArgs ...interface{}) {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+	if assert.EqualExportedValues(t, expected, actual, msgAndArgs...) {
+		return
+	}
+	t.FailNow()
+}
+
+// EqualExportedValuesf asserts that the types of two objects are equal and their public
+// fields are also equal. This is useful for comparing structs that have private fields
+// that could potentially differ.
+//
+// 	 type S struct {
+// 		Exported     	int
+// 		notExported   	int
+// 	 }
+// 	 assert.EqualExportedValuesf(t, S{1, 2}, S{1, 3}, "error message %s", "formatted") => true
+// 	 assert.EqualExportedValuesf(t, S{1, 2}, S{2, 3}, "error message %s", "formatted") => false
+func EqualExportedValuesf(t TestingT, expected interface{}, actual interface{}, msg string, args ...interface{}) {
+	if h, ok := t.(tHelper); ok {
+		h.Helper()
+	}
+	if assert.EqualExportedValuesf(t, expected, actual, msg, args...) {
+		return
+	}
+	t.FailNow()
+}
+
 // EqualValues asserts that two objects are equal or convertable to the same types
 // and equal.
 //

require/require_forward.go

@@ -156,6 +156,40 @@ func (a *Assertions) EqualErrorf(theError error, errString string, msg string, a
 	EqualErrorf(a.t, theError, errString, msg, args...)
 }
 
+// EqualExportedValues asserts that the types of two objects are equal and their public
+// fields are also equal. This is useful for comparing structs that have private fields
+// that could potentially differ.
+//
+// 	 type S struct {
+// 		Exported     	int
+// 		notExported   	int
+// 	 }
+// 	 a.EqualExportedValues(S{1, 2}, S{1, 3}) => true
+// 	 a.EqualExportedValues(S{1, 2}, S{2, 3}) => false
+func (a *Assertions) EqualExportedValues(expected interface{}, actual interface{}, msgAndArgs ...interface{}) {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	EqualExportedValues(a.t, expected, actual, msgAndArgs...)
+}
+
+// EqualExportedValuesf asserts that the types of two objects are equal and their public
+// fields are also equal. This is useful for comparing structs that have private fields
+// that could potentially differ.
+//
+// 	 type S struct {
+// 		Exported     	int
+// 		notExported   	int
+// 	 }
+// 	 a.EqualExportedValuesf(S{1, 2}, S{1, 3}, "error message %s", "formatted") => true
+// 	 a.EqualExportedValuesf(S{1, 2}, S{2, 3}, "error message %s", "formatted") => false
+func (a *Assertions) EqualExportedValuesf(expected interface{}, actual interface{}, msg string, args ...interface{}) {
+	if h, ok := a.t.(tHelper); ok {
+		h.Helper()
+	}
+	EqualExportedValuesf(a.t, expected, actual, msg, args...)
+}
+
 // EqualValues asserts that two objects are equal or convertable to the same types
 // and equal.
 //