[dmt] require x-config-version when conversions exist

pkg/linters/module/rules/conversions.go

@@ -106,10 +106,6 @@ func (r *ConversionsRule) CheckConversions(modulePath string, errorList *errors.
 		return
 	}
 
-	if cv.ConfigVersion == 0 {
-		return
-	}
-
 	folder := filepath.Join(modulePath, conversionsFolder)
 
 	stat, err := os.Stat(folder)
@@ -120,9 +116,11 @@ func (r *ConversionsRule) CheckConversions(modulePath string, errorList *errors.
 		return
 	}
 
-	if os.IsNotExist(err) || !stat.IsDir() {
-		errorList.WithFilePath(conversionsFolder).
-			Error("Conversions folder is not exist")
+	if err != nil || !stat.IsDir() {
+		if cv.ConfigVersion > 0 {
+			errorList.WithFilePath(conversionsFolder).
+				Error("Conversions folder is not exist")
+		}
 
 		return
 	}
@@ -164,13 +162,28 @@ func (r *ConversionsRule) CheckConversions(modulePath string, errorList *errors.
 	})
 
 	if len(versions) == 0 {
-		errorList.Errorf("No versions in folder: %q", folder)
+		if cv.ConfigVersion > 0 {
+			errorList.Errorf("No versions in folder: %q", folder)
+		}
+
+		return
+	}
+
+	if cv.ConfigVersion == 0 {
+		errorList.WithFilePath(configValuesFile).
+			Error("x-config-version is not set in config-values.yaml, but conversions exist")
 
 		return
 	}
 
 	slices.Sort(versions)
 
+	latestVersion := versions[len(versions)-1]
+	if cv.ConfigVersion != latestVersion {
+		errorList.WithFilePath(configValuesFile).
+			Errorf("x-config-version (%d) does not match latest conversion version (%d)", cv.ConfigVersion, latestVersion)
+	}
+
 	if versions[0] != 2 {
 		errorList.Errorf("You need to start with version number: 2")
 	}

pkg/linters/module/rules/conversions_test.go

@@ -0,0 +1,252 @@
+/*
+Copyright 2026 Flant JSC
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package rules
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/deckhouse/dmt/pkg/errors"
+)
+
+func TestNewConversionsRule(t *testing.T) {
+	tests := []struct {
+		name     string
+		disable  bool
+		expected bool
+	}{
+		{
+			name:     "enabled rule",
+			disable:  false,
+			expected: true,
+		},
+		{
+			name:     "disabled rule",
+			disable:  true,
+			expected: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			rule := NewConversionsRule(tt.disable)
+			assert.Equal(t, ConversionsRuleName, rule.GetName())
+			assert.Equal(t, tt.expected, rule.Enabled())
+		})
+	}
+}
+
+func TestConversionsRule_CheckConversions(t *testing.T) {
+	tests := []struct {
+		name           string
+		setup          func(dir string) error
+		expectedErrors []string
+	}{
+		{
+			name: "no config-values.yaml",
+			setup: func(dir string) error {
+				return nil
+			},
+			expectedErrors: []string{},
+		},
+		{
+			name: "config-values with x-config-version 0 and no conversions folder",
+			setup: func(dir string) error {
+				return os.MkdirAll(filepath.Join(dir, "openapi"), 0755)
+			},
+			expectedErrors: []string{},
+		},
+		{
+			name: "x-config-version set but no conversions folder",
+			setup: func(dir string) error {
+				openapiDir := filepath.Join(dir, "openapi")
+
+				if err := os.MkdirAll(openapiDir, 0755); err != nil {
+					return err
+				}
+
+				return os.WriteFile(filepath.Join(openapiDir, "config-values.yaml"), []byte("x-config-version: 2"), 0644)
+			},
+			expectedErrors: []string{
+				"Conversions folder is not exist",
+			},
+		},
+		{
+			name: "conversions exist but x-config-version is 0",
+			setup: func(dir string) error {
+				openapiDir := filepath.Join(dir, "openapi")
+				convDir := filepath.Join(openapiDir, "conversions")
+
+				if err := os.MkdirAll(convDir, 0755); err != nil {
+					return err
+				}
+
+				if err := os.WriteFile(filepath.Join(openapiDir, "config-values.yaml"), []byte("x-config-version: 0"), 0644); err != nil {
+					return err
+				}
+
+				return os.WriteFile(filepath.Join(convDir, "v2.yaml"), []byte(`version: 2
+conversions:
+  - del(.auth.password)
+description:
+  en: "v2"
+  ru: "v2 ru"`), 0644)
+			},
+			expectedErrors: []string{
+				"x-config-version is not set in config-values.yaml, but conversions exist",
+			},
+		},
+		{
+			name: "x-config-version does not match latest conversion version",
+			setup: func(dir string) error {
+				openapiDir := filepath.Join(dir, "openapi")
+				convDir := filepath.Join(openapiDir, "conversions")
+
+				if err := os.MkdirAll(convDir, 0755); err != nil {
+					return err
+				}
+
+				if err := os.WriteFile(filepath.Join(openapiDir, "config-values.yaml"), []byte("x-config-version: 5"), 0644); err != nil {
+					return err
+				}
+
+				return os.WriteFile(filepath.Join(convDir, "v2.yaml"), []byte(`version: 2
+conversions:
+  - del(.auth.password)
+description:
+  en: "v2"
+  ru: "v2 ru"`), 0644)
+			},
+			expectedErrors: []string{
+				"x-config-version (5) does not match latest conversion version (2)",
+			},
+		},
+		{
+			name: "valid conversions with matching x-config-version",
+			setup: func(dir string) error {
+				openapiDir := filepath.Join(dir, "openapi")
+				convDir := filepath.Join(openapiDir, "conversions")
+
+				if err := os.MkdirAll(convDir, 0755); err != nil {
+					return err
+				}
+
+				if err := os.WriteFile(filepath.Join(openapiDir, "config-values.yaml"), []byte("x-config-version: 2"), 0644); err != nil {
+					return err
+				}
+
+				return os.WriteFile(filepath.Join(convDir, "v2.yaml"), []byte(`version: 2
+conversions:
+  - del(.auth.password)
+description:
+  en: "v2"
+  ru: "v2 ru"`), 0644)
+			},
+			expectedErrors: []string{},
+		},
+		{
+			name: "conversions not starting from version 2",
+			setup: func(dir string) error {
+				openapiDir := filepath.Join(dir, "openapi")
+				convDir := filepath.Join(openapiDir, "conversions")
+
+				if err := os.MkdirAll(convDir, 0755); err != nil {
+					return err
+				}
+
+				if err := os.WriteFile(filepath.Join(openapiDir, "config-values.yaml"), []byte("x-config-version: 3"), 0644); err != nil {
+					return err
+				}
+
+				if err := os.WriteFile(filepath.Join(convDir, "v3.yaml"), []byte(`version: 3
+conversions:
+  - del(.auth.password)
+description:
+  en: "v3"
+  ru: "v3 ru"`), 0644); err != nil {
+					return err
+				}
+
+				return nil
+			},
+			expectedErrors: []string{
+				"You need to start with version number: 2",
+			},
+		},
+		{
+			name: "non-sequential conversion versions",
+			setup: func(dir string) error {
+				openapiDir := filepath.Join(dir, "openapi")
+				convDir := filepath.Join(openapiDir, "conversions")
+
+				if err := os.MkdirAll(convDir, 0755); err != nil {
+					return err
+				}
+
+				if err := os.WriteFile(filepath.Join(openapiDir, "config-values.yaml"), []byte("x-config-version: 4"), 0644); err != nil {
+					return err
+				}
+
+				if err := os.WriteFile(filepath.Join(convDir, "v2.yaml"), []byte(`version: 2
+conversions:
+  - del(.auth.password)
+description:
+  en: "v2"
+  ru: "v2 ru"`), 0644); err != nil {
+					return err
+				}
+
+				return os.WriteFile(filepath.Join(convDir, "v4.yaml"), []byte(`version: 4
+conversions:
+  - del(.auth)
+description:
+  en: "v4"
+  ru: "v4 ru"`), 0644)
+			},
+			expectedErrors: []string{
+				"No sequential versions between 4 and 2",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			tempDir := t.TempDir()
+
+			err := tt.setup(tempDir)
+			require.NoError(t, err)
+
+			rule := NewConversionsRule(false)
+			errorList := errors.NewLintRuleErrorsList()
+
+			rule.CheckConversions(tempDir, errorList)
+
+			errs := errorList.GetErrors()
+			assert.Len(t, errs, len(tt.expectedErrors), "Expected %d errors, got %d", len(tt.expectedErrors), len(errs))
+
+			for i, expectedError := range tt.expectedErrors {
+				if i < len(errs) {
+					assert.Contains(t, errs[i].Text, expectedError)
+				}
+			}
+		})
+	}
+}

pkg/testers/conversions/tester.go

@@ -79,7 +79,7 @@ func (t *Tester) Run(modulePath string) bool {
 		return true
 	}
 
-	if latestVersion > 0 && configVersion != latestVersion {
+	if configVersion > 0 && latestVersion > 0 && configVersion != latestVersion {
 		errorList.WithTestName("config values version mismatch").
 			AddTestResult("x-config-version with latest conversion version mismatch",
 				strconv.Itoa(latestVersion),
@@ -113,7 +113,8 @@ func (t *Tester) checkConversions(modulePath string, errorList *pkgerrors.TestEr
 	}
 
 	if configVersion == 0 {
-		return "", 0, false
+		errorList.Errorf("x-config-version is not set in config-values.yaml, but conversions exist")
+		return convFolder, 0, true
 	}
 
 	return convFolder, configVersion, true

pkg/testers/conversions/tester_test.go

@@ -360,6 +360,36 @@ description:
 	assert.Contains(t, errorList.GetErrors()[0].Text, "x-config-version")
 }
 
+func TestTester_ConversionsExistButConfigVersionZero(t *testing.T) {
+	tempDir := t.TempDir()
+
+	err := os.MkdirAll(filepath.Join(tempDir, "openapi", "conversions"), 0755)
+	require.NoError(t, err)
+
+	err = os.WriteFile(
+		filepath.Join(tempDir, "openapi", "config-values.yaml"),
+		[]byte("x-config-version: 0"),
+		0644,
+	)
+	require.NoError(t, err)
+
+	v2 := `version: 2
+conversions:
+  - del(.auth.password)
+description:
+  en: "v2"
+  ru: "v2 ru"`
+	err = os.WriteFile(filepath.Join(tempDir, "openapi", "conversions", "v2.yaml"), []byte(v2), 0644)
+	require.NoError(t, err)
+
+	errorList := pkgerrors.NewTestErrorsList()
+	tester := New(errorList)
+	tester.Run(tempDir)
+
+	assert.True(t, errorList.ContainsErrors())
+	assert.Contains(t, errorList.GetErrors()[0].Text, "x-config-version is not set")
+}
+
 func TestConversionsTester_ReportsTestcaseFailure(t *testing.T) {
 	tmpDir := t.TempDir()