vendor files

vendor/k8s.io/apimachinery/pkg/conversion/converter_test.go

@@ -0,0 +1,826 @@
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package conversion
+
+import (
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+	"testing"
+
+	"github.com/google/gofuzz"
+	flag "github.com/spf13/pflag"
+
+	"k8s.io/apimachinery/pkg/util/diff"
+)
+
+var fuzzIters = flag.Int("fuzz-iters", 50, "How many fuzzing iterations to do.")
+
+// Test a weird version/kind embedding format.
+type MyWeirdCustomEmbeddedVersionKindField struct {
+	ID         string `json:"ID,omitempty"`
+	APIVersion string `json:"myVersionKey,omitempty"`
+	ObjectKind string `json:"myKindKey,omitempty"`
+	Z          string `json:"Z,omitempty"`
+	Y          uint64 `json:"Y,omitempty"`
+}
+
+type TestType1 struct {
+	MyWeirdCustomEmbeddedVersionKindField `json:",inline"`
+	A                                     string               `json:"A,omitempty"`
+	B                                     int                  `json:"B,omitempty"`
+	C                                     int8                 `json:"C,omitempty"`
+	D                                     int16                `json:"D,omitempty"`
+	E                                     int32                `json:"E,omitempty"`
+	F                                     int64                `json:"F,omitempty"`
+	G                                     uint                 `json:"G,omitempty"`
+	H                                     uint8                `json:"H,omitempty"`
+	I                                     uint16               `json:"I,omitempty"`
+	J                                     uint32               `json:"J,omitempty"`
+	K                                     uint64               `json:"K,omitempty"`
+	L                                     bool                 `json:"L,omitempty"`
+	M                                     map[string]int       `json:"M,omitempty"`
+	N                                     map[string]TestType2 `json:"N,omitempty"`
+	O                                     *TestType2           `json:"O,omitempty"`
+	P                                     []TestType2          `json:"Q,omitempty"`
+}
+
+type TestType2 struct {
+	A string `json:"A,omitempty"`
+	B int    `json:"B,omitempty"`
+}
+
+type ExternalTestType2 struct {
+	A string `json:"A,omitempty"`
+	B int    `json:"B,omitempty"`
+}
+type ExternalTestType1 struct {
+	MyWeirdCustomEmbeddedVersionKindField `json:",inline"`
+	A                                     string                       `json:"A,omitempty"`
+	B                                     int                          `json:"B,omitempty"`
+	C                                     int8                         `json:"C,omitempty"`
+	D                                     int16                        `json:"D,omitempty"`
+	E                                     int32                        `json:"E,omitempty"`
+	F                                     int64                        `json:"F,omitempty"`
+	G                                     uint                         `json:"G,omitempty"`
+	H                                     uint8                        `json:"H,omitempty"`
+	I                                     uint16                       `json:"I,omitempty"`
+	J                                     uint32                       `json:"J,omitempty"`
+	K                                     uint64                       `json:"K,omitempty"`
+	L                                     bool                         `json:"L,omitempty"`
+	M                                     map[string]int               `json:"M,omitempty"`
+	N                                     map[string]ExternalTestType2 `json:"N,omitempty"`
+	O                                     *ExternalTestType2           `json:"O,omitempty"`
+	P                                     []ExternalTestType2          `json:"Q,omitempty"`
+}
+
+func testLogger(t *testing.T) DebugLogger {
+	// We don't set logger to eliminate rubbish logs in tests.
+	// If you want to switch it, simply switch it to: "return t"
+	return nil
+}
+
+func TestConverter_byteSlice(t *testing.T) {
+	c := NewConverter(DefaultNameFunc)
+	src := []byte{1, 2, 3}
+	dest := []byte{}
+	err := c.Convert(&src, &dest, 0, nil)
+	if err != nil {
+		t.Fatalf("expected no error")
+	}
+	if e, a := src, dest; !reflect.DeepEqual(e, a) {
+		t.Errorf("expected %#v, got %#v", e, a)
+	}
+}
+
+func TestConverter_MismatchedTypes(t *testing.T) {
+	c := NewConverter(DefaultNameFunc)
+
+	err := c.RegisterConversionFunc(
+		func(in *[]string, out *int, s Scope) error {
+			if str, err := strconv.Atoi((*in)[0]); err != nil {
+				return err
+			} else {
+				*out = str
+				return nil
+			}
+		},
+	)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+
+	src := []string{"5"}
+	var dest *int
+	err = c.Convert(&src, &dest, 0, nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if e, a := 5, *dest; e != a {
+		t.Errorf("expected %#v, got %#v", e, a)
+	}
+}
+
+func TestConverter_DefaultConvert(t *testing.T) {
+	type A struct {
+		Foo string
+		Baz int
+	}
+	type B struct {
+		Bar string
+		Baz int
+	}
+	c := NewConverter(DefaultNameFunc)
+	c.Debug = testLogger(t)
+	c.nameFunc = func(t reflect.Type) string { return "MyType" }
+
+	// Ensure conversion funcs can call DefaultConvert to get default behavior,
+	// then fixup remaining fields manually
+	err := c.RegisterConversionFunc(func(in *A, out *B, s Scope) error {
+		if err := s.DefaultConvert(in, out, IgnoreMissingFields); err != nil {
+			return err
+		}
+		out.Bar = in.Foo
+		return nil
+	})
+	if err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+
+	x := A{"hello, intrepid test reader!", 3}
+	y := B{}
+
+	err = c.Convert(&x, &y, 0, nil)
+	if err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	if e, a := x.Foo, y.Bar; e != a {
+		t.Errorf("expected %v, got %v", e, a)
+	}
+	if e, a := x.Baz, y.Baz; e != a {
+		t.Errorf("expected %v, got %v", e, a)
+	}
+}
+
+func TestConverter_DeepCopy(t *testing.T) {
+	type A struct {
+		Foo *string
+		Bar []string
+		Baz interface{}
+		Qux map[string]string
+	}
+	c := NewConverter(DefaultNameFunc)
+	c.Debug = testLogger(t)
+
+	foo, baz := "foo", "baz"
+	x := A{
+		Foo: &foo,
+		Bar: []string{"bar"},
+		Baz: &baz,
+		Qux: map[string]string{"qux": "qux"},
+	}
+	y := A{}
+
+	if err := c.Convert(&x, &y, 0, nil); err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	*x.Foo = "foo2"
+	x.Bar[0] = "bar2"
+	*x.Baz.(*string) = "baz2"
+	x.Qux["qux"] = "qux2"
+	if e, a := *x.Foo, *y.Foo; e == a {
+		t.Errorf("expected difference between %v and %v", e, a)
+	}
+	if e, a := x.Bar, y.Bar; reflect.DeepEqual(e, a) {
+		t.Errorf("expected difference between %v and %v", e, a)
+	}
+	if e, a := *x.Baz.(*string), *y.Baz.(*string); e == a {
+		t.Errorf("expected difference between %v and %v", e, a)
+	}
+	if e, a := x.Qux, y.Qux; reflect.DeepEqual(e, a) {
+		t.Errorf("expected difference between %v and %v", e, a)
+	}
+}
+
+func TestConverter_CallsRegisteredFunctions(t *testing.T) {
+	type A struct {
+		Foo string
+		Baz int
+	}
+	type B struct {
+		Bar string
+		Baz int
+	}
+	type C struct{}
+	c := NewConverter(DefaultNameFunc)
+	c.Debug = testLogger(t)
+	err := c.RegisterConversionFunc(func(in *A, out *B, s Scope) error {
+		out.Bar = in.Foo
+		return s.Convert(&in.Baz, &out.Baz, 0)
+	})
+	if err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	err = c.RegisterConversionFunc(func(in *B, out *A, s Scope) error {
+		out.Foo = in.Bar
+		return s.Convert(&in.Baz, &out.Baz, 0)
+	})
+	if err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+
+	x := A{"hello, intrepid test reader!", 3}
+	y := B{}
+
+	err = c.Convert(&x, &y, 0, nil)
+	if err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	if e, a := x.Foo, y.Bar; e != a {
+		t.Errorf("expected %v, got %v", e, a)
+	}
+	if e, a := x.Baz, y.Baz; e != a {
+		t.Errorf("expected %v, got %v", e, a)
+	}
+
+	z := B{"all your test are belong to us", 42}
+	w := A{}
+
+	err = c.Convert(&z, &w, 0, nil)
+	if err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	if e, a := z.Bar, w.Foo; e != a {
+		t.Errorf("expected %v, got %v", e, a)
+	}
+	if e, a := z.Baz, w.Baz; e != a {
+		t.Errorf("expected %v, got %v", e, a)
+	}
+
+	err = c.RegisterConversionFunc(func(in *A, out *C, s Scope) error {
+		return fmt.Errorf("C can't store an A, silly")
+	})
+	if err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	err = c.Convert(&A{}, &C{}, 0, nil)
+	if err == nil {
+		t.Errorf("unexpected non-error")
+	}
+}
+
+func TestConverter_IgnoredConversion(t *testing.T) {
+	type A struct{}
+	type B struct{}
+
+	count := 0
+	c := NewConverter(DefaultNameFunc)
+	if err := c.RegisterConversionFunc(func(in *A, out *B, s Scope) error {
+		count++
+		return nil
+	}); err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	if err := c.RegisterIgnoredConversion(&A{}, &B{}); err != nil {
+		t.Fatal(err)
+	}
+	a := A{}
+	b := B{}
+	if err := c.Convert(&a, &b, 0, nil); err != nil {
+		t.Errorf("%v", err)
+	}
+	if count != 0 {
+		t.Errorf("unexpected number of conversion invocations")
+	}
+}
+
+func TestConverter_IgnoredConversionNested(t *testing.T) {
+	type C string
+	type A struct {
+		C C
+	}
+	type B struct {
+		C C
+	}
+
+	c := NewConverter(DefaultNameFunc)
+	typed := C("")
+	if err := c.RegisterIgnoredConversion(&typed, &typed); err != nil {
+		t.Fatal(err)
+	}
+	a := A{C: C("test")}
+	b := B{C: C("other")}
+	if err := c.Convert(&a, &b, AllowDifferentFieldTypeNames, nil); err != nil {
+		t.Errorf("%v", err)
+	}
+	if b.C != C("other") {
+		t.Errorf("expected no conversion of field C: %#v", b)
+	}
+}
+
+func TestConverter_GeneratedConversionOverriden(t *testing.T) {
+	type A struct{}
+	type B struct{}
+	c := NewConverter(DefaultNameFunc)
+	if err := c.RegisterConversionFunc(func(in *A, out *B, s Scope) error {
+		return nil
+	}); err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	if err := c.RegisterGeneratedConversionFunc(func(in *A, out *B, s Scope) error {
+		return fmt.Errorf("generated function should be overriden")
+	}); err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+
+	a := A{}
+	b := B{}
+	if err := c.Convert(&a, &b, 0, nil); err != nil {
+		t.Errorf("%v", err)
+	}
+}
+
+func TestConverter_WithConversionOverriden(t *testing.T) {
+	type A struct{}
+	type B struct{}
+	c := NewConverter(DefaultNameFunc)
+	if err := c.RegisterConversionFunc(func(in *A, out *B, s Scope) error {
+		return fmt.Errorf("conversion function should be overriden")
+	}); err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	if err := c.RegisterGeneratedConversionFunc(func(in *A, out *B, s Scope) error {
+		return fmt.Errorf("generated function should be overriden")
+	}); err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+
+	ext := NewConversionFuncs()
+	ext.Add(func(in *A, out *B, s Scope) error {
+		return nil
+	})
+	newc := c.WithConversions(ext)
+
+	a := A{}
+	b := B{}
+	if err := c.Convert(&a, &b, 0, nil); err == nil || err.Error() != "conversion function should be overriden" {
+		t.Errorf("unexpected error: %v", err)
+	}
+	if err := newc.Convert(&a, &b, 0, nil); err != nil {
+		t.Errorf("%v", err)
+	}
+}
+
+func TestConverter_MapsStringArrays(t *testing.T) {
+	type A struct {
+		Foo   string
+		Baz   int
+		Other string
+	}
+	c := NewConverter(DefaultNameFunc)
+	c.Debug = testLogger(t)
+	if err := c.RegisterConversionFunc(func(input *[]string, out *string, s Scope) error {
+		if len(*input) == 0 {
+			*out = ""
+		}
+		*out = (*input)[0]
+		return nil
+	}); err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+
+	x := map[string][]string{
+		"Foo":   {"bar"},
+		"Baz":   {"1"},
+		"Other": {"", "test"},
+		"other": {"wrong"},
+	}
+	y := A{"test", 2, "something"}
+
+	if err := c.Convert(&x, &y, AllowDifferentFieldTypeNames, nil); err == nil {
+		t.Error("unexpected non-error")
+	}
+
+	if err := c.RegisterConversionFunc(func(input *[]string, out *int, s Scope) error {
+		if len(*input) == 0 {
+			*out = 0
+		}
+		str := (*input)[0]
+		i, err := strconv.Atoi(str)
+		if err != nil {
+			return err
+		}
+		*out = i
+		return nil
+	}); err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+
+	if err := c.Convert(&x, &y, AllowDifferentFieldTypeNames, nil); err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	if !reflect.DeepEqual(y, A{"bar", 1, ""}) {
+		t.Errorf("unexpected result: %#v", y)
+	}
+}
+
+func TestConverter_MapsStringArraysWithMappingKey(t *testing.T) {
+	type A struct {
+		Foo   string `json:"test"`
+		Baz   int
+		Other string
+	}
+	c := NewConverter(DefaultNameFunc)
+	c.Debug = testLogger(t)
+	if err := c.RegisterConversionFunc(func(input *[]string, out *string, s Scope) error {
+		if len(*input) == 0 {
+			*out = ""
+		}
+		*out = (*input)[0]
+		return nil
+	}); err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+
+	x := map[string][]string{
+		"Foo":  {"bar"},
+		"test": {"baz"},
+	}
+	y := A{"", 0, ""}
+
+	if err := c.Convert(&x, &y, AllowDifferentFieldTypeNames|IgnoreMissingFields, &Meta{}); err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	if !reflect.DeepEqual(y, A{"bar", 0, ""}) {
+		t.Errorf("unexpected result: %#v", y)
+	}
+
+	mapping := func(key string, sourceTag, destTag reflect.StructTag) (source string, dest string) {
+		if s := destTag.Get("json"); len(s) > 0 {
+			return strings.SplitN(s, ",", 2)[0], key
+		}
+		return key, key
+	}
+
+	if err := c.Convert(&x, &y, AllowDifferentFieldTypeNames|IgnoreMissingFields, &Meta{KeyNameMapping: mapping}); err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	if !reflect.DeepEqual(y, A{"baz", 0, ""}) {
+		t.Errorf("unexpected result: %#v", y)
+	}
+}
+
+func TestConverter_fuzz(t *testing.T) {
+	// Use the same types from the scheme test.
+	table := []struct {
+		from, to, check interface{}
+	}{
+		{&TestType1{}, &ExternalTestType1{}, &TestType1{}},
+		{&ExternalTestType1{}, &TestType1{}, &ExternalTestType1{}},
+	}
+
+	f := fuzz.New().NilChance(.5).NumElements(0, 100)
+	c := NewConverter(DefaultNameFunc)
+	c.nameFunc = func(t reflect.Type) string {
+		// Hide the fact that we don't have separate packages for these things.
+		return map[reflect.Type]string{
+			reflect.TypeOf(TestType1{}):         "TestType1",
+			reflect.TypeOf(ExternalTestType1{}): "TestType1",
+			reflect.TypeOf(TestType2{}):         "TestType2",
+			reflect.TypeOf(ExternalTestType2{}): "TestType2",
+		}[t]
+	}
+	c.Debug = testLogger(t)
+
+	for i, item := range table {
+		for j := 0; j < *fuzzIters; j++ {
+			f.Fuzz(item.from)
+			err := c.Convert(item.from, item.to, 0, nil)
+			if err != nil {
+				t.Errorf("(%v, %v): unexpected error: %v", i, j, err)
+				continue
+			}
+			err = c.Convert(item.to, item.check, 0, nil)
+			if err != nil {
+				t.Errorf("(%v, %v): unexpected error: %v", i, j, err)
+				continue
+			}
+			if e, a := item.from, item.check; !reflect.DeepEqual(e, a) {
+				t.Errorf("(%v, %v): unexpected diff: %v", i, j, diff.ObjectDiff(e, a))
+			}
+		}
+	}
+}
+
+func TestConverter_MapElemAddr(t *testing.T) {
+	type Foo struct {
+		A map[int]int
+	}
+	type Bar struct {
+		A map[string]string
+	}
+	c := NewConverter(DefaultNameFunc)
+	c.Debug = testLogger(t)
+	err := c.RegisterConversionFunc(
+		func(in *int, out *string, s Scope) error {
+			*out = fmt.Sprintf("%v", *in)
+			return nil
+		},
+	)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	err = c.RegisterConversionFunc(
+		func(in *string, out *int, s Scope) error {
+			if str, err := strconv.Atoi(*in); err != nil {
+				return err
+			} else {
+				*out = str
+				return nil
+			}
+		},
+	)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	f := fuzz.New().NilChance(0).NumElements(3, 3)
+	first := Foo{}
+	second := Bar{}
+	f.Fuzz(&first)
+	err = c.Convert(&first, &second, AllowDifferentFieldTypeNames, nil)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	third := Foo{}
+	err = c.Convert(&second, &third, AllowDifferentFieldTypeNames, nil)
+	if e, a := first, third; !reflect.DeepEqual(e, a) {
+		t.Errorf("Unexpected diff: %v", diff.ObjectDiff(e, a))
+	}
+}
+
+func TestConverter_tags(t *testing.T) {
+	type Foo struct {
+		A string `test:"foo"`
+	}
+	type Bar struct {
+		A string `test:"bar"`
+	}
+	c := NewConverter(DefaultNameFunc)
+	c.Debug = testLogger(t)
+	err := c.RegisterConversionFunc(
+		func(in *string, out *string, s Scope) error {
+			if e, a := "foo", s.SrcTag().Get("test"); e != a {
+				t.Errorf("expected %v, got %v", e, a)
+			}
+			if e, a := "bar", s.DestTag().Get("test"); e != a {
+				t.Errorf("expected %v, got %v", e, a)
+			}
+			return nil
+		},
+	)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	err = c.Convert(&Foo{}, &Bar{}, AllowDifferentFieldTypeNames, nil)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+}
+
+func TestConverter_meta(t *testing.T) {
+	type Foo struct{ A string }
+	type Bar struct{ A string }
+	c := NewConverter(DefaultNameFunc)
+	c.Debug = testLogger(t)
+	checks := 0
+	err := c.RegisterConversionFunc(
+		func(in *Foo, out *Bar, s Scope) error {
+			if s.Meta() == nil {
+				t.Errorf("Meta did not get passed!")
+			}
+			checks++
+			s.Convert(&in.A, &out.A, 0)
+			return nil
+		},
+	)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	err = c.RegisterConversionFunc(
+		func(in *string, out *string, s Scope) error {
+			if s.Meta() == nil {
+				t.Errorf("Meta did not get passed a second time!")
+			}
+			checks++
+			return nil
+		},
+	)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	err = c.Convert(&Foo{}, &Bar{}, 0, &Meta{})
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	if checks != 2 {
+		t.Errorf("Registered functions did not get called.")
+	}
+}
+
+func TestConverter_flags(t *testing.T) {
+	type Foo struct{ A string }
+	type Bar struct{ A string }
+	table := []struct {
+		from, to      interface{}
+		flags         FieldMatchingFlags
+		shouldSucceed bool
+	}{
+		// Check that DestFromSource allows extra fields only in source.
+		{
+			from:          &struct{ A string }{},
+			to:            &struct{ A, B string }{},
+			flags:         DestFromSource,
+			shouldSucceed: false,
+		}, {
+			from:          &struct{ A, B string }{},
+			to:            &struct{ A string }{},
+			flags:         DestFromSource,
+			shouldSucceed: true,
+		},
+
+		// Check that SourceToDest allows for extra fields only in dest.
+		{
+			from:          &struct{ A string }{},
+			to:            &struct{ A, B string }{},
+			flags:         SourceToDest,
+			shouldSucceed: true,
+		}, {
+			from:          &struct{ A, B string }{},
+			to:            &struct{ A string }{},
+			flags:         SourceToDest,
+			shouldSucceed: false,
+		},
+
+		// Check that IgnoreMissingFields makes the above failure cases pass.
+		{
+			from:          &struct{ A string }{},
+			to:            &struct{ A, B string }{},
+			flags:         DestFromSource | IgnoreMissingFields,
+			shouldSucceed: true,
+		}, {
+			from:          &struct{ A, B string }{},
+			to:            &struct{ A string }{},
+			flags:         SourceToDest | IgnoreMissingFields,
+			shouldSucceed: true,
+		},
+
+		// Check that the field type name must match unless
+		// AllowDifferentFieldTypeNames is specified.
+		{
+			from:          &struct{ A, B Foo }{},
+			to:            &struct{ A Bar }{},
+			flags:         DestFromSource,
+			shouldSucceed: false,
+		}, {
+			from:          &struct{ A Foo }{},
+			to:            &struct{ A, B Bar }{},
+			flags:         SourceToDest,
+			shouldSucceed: false,
+		}, {
+			from:          &struct{ A, B Foo }{},
+			to:            &struct{ A Bar }{},
+			flags:         DestFromSource | AllowDifferentFieldTypeNames,
+			shouldSucceed: true,
+		}, {
+			from:          &struct{ A Foo }{},
+			to:            &struct{ A, B Bar }{},
+			flags:         SourceToDest | AllowDifferentFieldTypeNames,
+			shouldSucceed: true,
+		},
+	}
+	f := fuzz.New().NilChance(.5).NumElements(0, 100)
+	c := NewConverter(DefaultNameFunc)
+	c.Debug = testLogger(t)
+
+	for i, item := range table {
+		for j := 0; j < *fuzzIters; j++ {
+			f.Fuzz(item.from)
+			err := c.Convert(item.from, item.to, item.flags, nil)
+			if item.shouldSucceed && err != nil {
+				t.Errorf("(%v, %v): unexpected error: %v", i, j, err)
+				continue
+			}
+			if !item.shouldSucceed && err == nil {
+				t.Errorf("(%v, %v): unexpected non-error", i, j)
+				continue
+			}
+		}
+	}
+}
+
+func TestConverter_FieldRename(t *testing.T) {
+	type WeirdMeta struct {
+		Name string
+		Type string
+	}
+	type NameMeta struct {
+		Name string
+	}
+	type TypeMeta struct {
+		Type string
+	}
+	type A struct {
+		WeirdMeta
+	}
+	type B struct {
+		TypeMeta
+		NameMeta
+	}
+
+	c := NewConverter(DefaultNameFunc)
+	err := c.SetStructFieldCopy(WeirdMeta{}, "WeirdMeta", TypeMeta{}, "TypeMeta")
+	if err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	err = c.SetStructFieldCopy(WeirdMeta{}, "WeirdMeta", NameMeta{}, "NameMeta")
+	if err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	err = c.SetStructFieldCopy(TypeMeta{}, "TypeMeta", WeirdMeta{}, "WeirdMeta")
+	if err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	err = c.SetStructFieldCopy(NameMeta{}, "NameMeta", WeirdMeta{}, "WeirdMeta")
+	if err != nil {
+		t.Fatalf("unexpected error %v", err)
+	}
+	c.Debug = testLogger(t)
+
+	aVal := &A{
+		WeirdMeta: WeirdMeta{
+			Name: "Foo",
+			Type: "Bar",
+		},
+	}
+
+	bVal := &B{
+		TypeMeta: TypeMeta{"Bar"},
+		NameMeta: NameMeta{"Foo"},
+	}
+
+	table := map[string]struct {
+		from, to, expect interface{}
+		flags            FieldMatchingFlags
+	}{
+		"to": {
+			aVal,
+			&B{},
+			bVal,
+			AllowDifferentFieldTypeNames | SourceToDest | IgnoreMissingFields,
+		},
+		"from": {
+			bVal,
+			&A{},
+			aVal,
+			AllowDifferentFieldTypeNames | SourceToDest,
+		},
+		"toDestFirst": {
+			aVal,
+			&B{},
+			bVal,
+			AllowDifferentFieldTypeNames,
+		},
+		"fromDestFirst": {
+			bVal,
+			&A{},
+			aVal,
+			AllowDifferentFieldTypeNames | IgnoreMissingFields,
+		},
+	}
+
+	for name, item := range table {
+		err := c.Convert(item.from, item.to, item.flags, nil)
+		if err != nil {
+			t.Errorf("%v: unexpected error: %v", name, err)
+			continue
+		}
+		if e, a := item.expect, item.to; !reflect.DeepEqual(e, a) {
+			t.Errorf("%v: unexpected diff: %v", name, diff.ObjectDiff(e, a))
+		}
+	}
+}