Check assignability
diff --git a/mapstructure.go b/mapstructure.go
index d4a49ed..f1a0c80 100644
--- a/mapstructure.go
+++ b/mapstructure.go
@@ -2,6 +2,7 @@
import (
"errors"
+ "fmt"
"reflect"
"strings"
)
@@ -60,6 +61,15 @@
panic("map value is not valid")
}
+ mapValType := mapVal.Type()
+ if !mapValType.AssignableTo(field.Type()) {
+ // If the value in the map can't be assigned to the field
+ // in the struct, then this is a problem...
+ return fmt.Errorf(
+ "field '%s' expected type '%s', got '%s'",
+ fieldName, field.Type(), mapValType)
+ }
+
field.Set(mapVal)
}
diff --git a/mapstructure_test.go b/mapstructure_test.go
index ec47e70..3ec2a3a 100644
--- a/mapstructure_test.go
+++ b/mapstructure_test.go
@@ -4,8 +4,9 @@
type Basic struct {
Vstring string
- Vint int
- Vbool bool
+ Vint int
+ Vbool bool
+ Vextra string
}
func TestBasicTypes(t *testing.T) {
@@ -13,8 +14,8 @@
input := map[string]interface{}{
"vstring": "foo",
- "vint": 42,
- "vbool": true,
+ "vint": 42,
+ "vbool": true,
}
var result Basic
@@ -35,6 +36,29 @@
if result.Vbool != true {
t.Errorf("vbool value should be true: %#v", result.Vbool)
}
+
+ if result.Vextra != "" {
+ t.Errorf("vextra value should be empty: %#v", result.Vextra)
+ }
+}
+
+func TestInvalidType(t *testing.T) {
+ t.Parallel()
+
+ input := map[string]interface{}{
+ "vstring": 42,
+ }
+
+ var result Basic
+ err := MapToStruct(input, &result)
+ if err == nil {
+ t.Error("error should exist")
+ t.FailNow()
+ }
+
+ if err.Error() != "field 'Vstring' expected type 'string', got 'int'" {
+ t.Errorf("got unexpected error: %s", err)
+ }
}
func TestNonPtrValue(t *testing.T) {
