diff now does sort first

cmd/yamltool/diff_test.go

@@ -0,0 +1,76 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/goccy/go-yaml"
+	"github.com/stretchr/testify/require"
+	"github.com/stretchr/testify/suite"
+)
+
+type DiffSuite struct {
+	suite.Suite
+}
+
+func TestDiffSuite(t *testing.T) {
+	suite.Run(t, new(DiffSuite))
+}
+
+func (s *DiffSuite) TestCompareIgnoresTopLevelMapKeyOrder() {
+	diff1, diff2 := s.compareDocuments(`
+first: 1
+second: 2
+`, `
+second: 2
+first: 1
+`)
+
+	require.Empty(s.T(), diff1)
+	require.Empty(s.T(), diff2)
+}
+
+func (s *DiffSuite) TestCompareIgnoresMapKeyOrderInArray() {
+	diff1, diff2 := s.compareDocuments(`
+items:
+  - name: alpha
+    value: 1
+  - name: beta
+    value: 2
+`, `
+items:
+  - value: 1
+    name: alpha
+  - value: 2
+    name: beta
+`)
+
+	require.Empty(s.T(), diff1)
+	require.Empty(s.T(), diff2)
+}
+
+func (s *DiffSuite) TestCompareStillDetectsChangedMapValue() {
+	diff1, diff2 := s.compareDocuments(`
+items:
+  - name: alpha
+    value: 1
+`, `
+items:
+  - value: 2
+    name: alpha
+`)
+
+	require.NotEmpty(s.T(), diff1)
+	require.NotEmpty(s.T(), diff2)
+}
+
+func (s *DiffSuite) compareDocuments(yaml1Data, yaml2Data string) (yaml.MapSlice, yaml.MapSlice) {
+	s.T().Helper()
+
+	yaml1, err := parse([]byte(yaml1Data))
+	require.NoError(s.T(), err)
+	yaml2, err := parse([]byte(yaml2Data))
+	require.NoError(s.T(), err)
+
+	diff1, diff2 := compare(yaml1, yaml2)
+	return diff1, diff2
+}