fix(app): add test coverage to FindStructField (#1769)

Signed-off-by: Artur Troian <[email protected]>

app/types/app.go

@@ -1,6 +1,7 @@
 package types
 
 import (
+	"errors"
 	"fmt"
 	"reflect"
 
@@ -38,6 +39,10 @@ var (
 	upgrades = map[string]UpgradeInitFn{}
 )
 
+var (
+	ErrEmptyFieldName = errors.New("empty field name")
+)
+
 type IUpgrade interface {
 	StoreLoader() *storetypes.StoreUpgrades
 	UpgradeHandler() upgradetypes.UpgradeHandler
@@ -101,6 +106,9 @@ func GetUpgradesList() map[string]UpgradeInitFn {
 // and has the defined member field, if error is nil, the given
 // fieldName exists and is accessible with reflect.
 func FindStructField[C any](obj interface{}, fieldName string) (C, error) {
+	if fieldName == "" {
+		return *new(C), ErrEmptyFieldName
+	}
 	rValue := reflect.ValueOf(obj)
 
 	if rValue.Type().Kind() != reflect.Ptr {

app/types/app_test.go

@@ -0,0 +1,65 @@
+package types
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestFindStructFieldEmptyField(t *testing.T) {
+	type testType struct {
+		Val string
+	}
+	testStruct := testType{}
+
+	_, err := FindStructField[string](testStruct, "")
+	require.EqualError(t, err, ErrEmptyFieldName.Error())
+}
+
+func TestFindStructFieldObjectAsValue(t *testing.T) {
+	type testType struct {
+		Val string
+	}
+	testStruct := testType{}
+
+	val, err := FindStructField[string](testStruct, "Val")
+	require.NoError(t, err)
+	require.Equal(t, "", val)
+}
+
+func TestFindStructFieldObjectAsPointer(t *testing.T) {
+	type testType struct {
+		Val string
+	}
+	testStruct := testType{
+		Val: "testVal",
+	}
+
+	val, err := FindStructField[string](&testStruct, "Val")
+	require.NoError(t, err)
+	require.Equal(t, "testVal", val)
+}
+
+func TestFindStructFieldUnknownField(t *testing.T) {
+	type testType struct {
+		Val string
+	}
+	testStruct := testType{
+		Val: "testVal",
+	}
+
+	_, err := FindStructField[string](&testStruct, "Vals")
+	require.Error(t, err)
+}
+
+func TestFindStructFieldNonMatchingType(t *testing.T) {
+	type testType struct {
+		Val string
+	}
+	testStruct := testType{
+		Val: "testVal",
+	}
+
+	_, err := FindStructField[int](&testStruct, "Vals")
+	require.Error(t, err)
+}