Fix mitchellhGH-340: Decoding array of slices causes panic

nolag · Oct 30, 2023 · 58a4c3b · 58a4c3b
1 parent bf980b3
commit 58a4c3b
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Showing 2 changed files with 17 additions and 1 deletion.
diff --git a/mapstructure.go b/mapstructure.go
@@ -1163,7 +1163,7 @@ func (d *Decoder) decodeArray(name string, data interface{}, val reflect.Value)
 
 	valArray := val
 
-	if valArray.Interface() == reflect.Zero(valArray.Type()).Interface() || d.config.ZeroFields {
+	if valArray.Comparable() && valArray.Interface() == reflect.Zero(valArray.Type()).Interface() || d.config.ZeroFields {
 		// Check input type
 		if dataValKind != reflect.Array && dataValKind != reflect.Slice {
 			if d.config.WeaklyTypedInput {

diff --git a/mapstructure_bugs_test.go b/mapstructure_bugs_test.go
@@ -625,3 +625,19 @@ func TestMapOmitEmptyWithEmptyFieldnameInTag(t *testing.T) {
 		t.Fatalf("fail: %#v", m)
 	}
 }
+
+// GH-340: Decoding array of slices causes panic
+type HasNonComparableType struct {
+	NonComparableType [2][]byte
+}
+
+func TestDecode_nonComparableType(t *testing.T) {
+	decodeTo := &HasNonComparableType{}
+	expected := [2][]byte{{1, 2}, {3, 4, 5}}
+	if err := Decode(map[string]interface{}{"NonComparableType": expected}, &decodeTo); err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(expected, decodeTo.NonComparableType) {
+		t.Fatalf("fail: %#v", decodeTo.NonComparableType)
+	}
+}