diff options
| author | Matthew Dempsky <mdempsky@google.com> | 2020-04-19 13:59:16 -0700 |
|---|---|---|
| committer | Matthew Dempsky <mdempsky@google.com> | 2020-04-21 05:41:33 +0000 |
| commit | 0eb694e9c217c051cd8cc18258bf593d0be7fb8d (patch) | |
| tree | 40d746cd173648d4bf00fc78486eac4494a16964 /src/reflect | |
| parent | 925516309128f20bb11a38f3e5265f23360a28ba (diff) | |
| download | go-0eb694e9c217c051cd8cc18258bf593d0be7fb8d.tar.gz go-0eb694e9c217c051cd8cc18258bf593d0be7fb8d.zip | |
reflect: disallow invoking methods on unexported embedded fields
Given:
type u struct{}
func (u) M() {}
type t struct { u; u2 u }
var v = reflect.ValueOf(t{})
Package reflect allows:
v.Method(0) // v.M
v.Field(0).Method(0) // v.u.M
but panics from:
v.Field(1).Method(0) // v.u2.M
because u2 is not an exported field. However, u is not an exported
field either, so this is inconsistent.
It seems like this behavior originates from #12367, where it was
decided to allow traversing unexported embedded fields to be able to
access their exported fields, since package reflect doesn't provide an
alternative way to access promoted fields directly.
But extending that logic to promoted *methods* was inappropriate,
because package reflect's normal method handling logic already handles
promoted methods correctly. This CL corrects that mistake.
Fixes #38521.
Change-Id: If65008965f35927b4e7927cddf8614695288eb19
Reviewed-on: https://go-review.googlesource.com/c/go/+/228902
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Diffstat (limited to 'src/reflect')
| -rw-r--r-- | src/reflect/all_test.go | 4 | ||||
| -rw-r--r-- | src/reflect/value.go | 2 |
2 files changed, 3 insertions, 3 deletions
diff --git a/src/reflect/all_test.go b/src/reflect/all_test.go index cb0c8344f3..3129ff8e5d 100644 --- a/src/reflect/all_test.go +++ b/src/reflect/all_test.go @@ -3567,7 +3567,7 @@ func TestCallPanic(t *testing.T) { i := timp(0) v := ValueOf(T{i, i, i, i, T2{i, i}, i, i, T2{i, i}}) - ok(func() { call(v.Field(0).Method(0)) }) // .t0.W + badCall(func() { call(v.Field(0).Method(0)) }) // .t0.W badCall(func() { call(v.Field(0).Elem().Method(0)) }) // .t0.W badCall(func() { call(v.Field(0).Method(1)) }) // .t0.w badMethod(func() { call(v.Field(0).Elem().Method(2)) }) // .t0.w @@ -3588,7 +3588,7 @@ func TestCallPanic(t *testing.T) { ok(func() { call(v.Field(4).Field(0).Method(0)) }) // .NamedT2.T1.Y ok(func() { call(v.Field(4).Field(0).Elem().Method(0)) }) // .NamedT2.T1.W - ok(func() { call(v.Field(4).Field(1).Method(0)) }) // .NamedT2.t0.W + badCall(func() { call(v.Field(4).Field(1).Method(0)) }) // .NamedT2.t0.W badCall(func() { call(v.Field(4).Field(1).Elem().Method(0)) }) // .NamedT2.t0.W badCall(func() { call(v.Field(5).Method(0)) }) // .namedT0.W diff --git a/src/reflect/value.go b/src/reflect/value.go index 57ac65e084..de6f22b5b3 100644 --- a/src/reflect/value.go +++ b/src/reflect/value.go @@ -1315,7 +1315,7 @@ func (v Value) Method(i int) Value { if v.typ.Kind() == Interface && v.IsNil() { panic("reflect: Method on nil interface value") } - fl := v.flag & (flagStickyRO | flagIndir) // Clear flagEmbedRO + fl := v.flag.ro() | (v.flag & flagIndir) fl |= flag(Func) fl |= flag(i)<<flagMethodShift | flagMethod return Value{v.typ, v.ptr, fl} |