Fix internal/command/validate_test.go: TestValidate_json* (#3202)

Signed-off-by: Diogenes Fernandes <diofeher@gmail.com>

internal/command/validate_test.go

@@ -10,6 +10,8 @@ import (
 	"io"
 	"os"
 	"path"
+	"path/filepath"
+	"runtime"
 	"strings"
 	"testing"
 
@@ -352,6 +354,43 @@ func TestValidate_json(t *testing.T) {
 		{"validate-invalid/missing_defined_var", true},
 	}
 
+	cmpOpts := cmp.Options{
+		// Filenames are defined as Unix paths in `output.json`, this
+		// is needed to convert them to the correct path for the current OS.
+		cmp.FilterPath(
+			func(p cmp.Path) bool {
+				field := p.Last().String()
+				return field == `["filename"]`
+			},
+			//
+			cmp.Transformer("filename", func(filename interface{}) string {
+				convertedFilename, ok := filename.(string)
+				if !ok {
+					t.Fatalf("failed to convert filename to string: %v", filename)
+				}
+				return filepath.FromSlash(convertedFilename)
+			}),
+		),
+		// Detail field contains file path along with other information. '/' are
+		// being replaced if Windows is the current OS.
+		cmp.FilterPath(
+			func(p cmp.Path) bool {
+				field := p.Last().String()
+				return field == `["detail"]`
+			},
+			cmp.Transformer("detail", func(detail interface{}) string {
+				convertedDetail, ok := detail.(string)
+				if !ok {
+					t.Fatalf("failed to convert detail to string: %v", detail)
+				}
+				if runtime.GOOS == "windows" {
+					convertedDetail = strings.ReplaceAll(convertedDetail, `\`, `/`)
+				}
+				return convertedDetail
+			}),
+		),
+	}
+
 	for _, tc := range tests {
 		t.Run(tc.path, func(t *testing.T) {
 			var want, got map[string]interface{}
@@ -378,7 +417,7 @@ func TestValidate_json(t *testing.T) {
 				t.Fatalf("failed to unmarshal actual JSON: %s", err)
 			}
 
-			if !cmp.Equal(got, want) {
+			if !cmp.Equal(got, want, cmpOpts) {
 				t.Errorf("wrong output:\n %v\n", cmp.Diff(got, want))
 				t.Errorf("raw output:\n%s\n", gotString)
 			}