Fix linter issues and add dummy usage of enum constants to prevent linter warnings

Author: umputun

_examples/status/job_status_enum.go

@@ -27,7 +27,7 @@ func TestJobStatus(t *testing.T) {
 		d := Data{Status: JobStatusActive}
 		b, err := json.Marshal(d)
 		require.NoError(t, err)
-		assert.Equal(t, `{"status":"active"}`, string(b))
+		assert.JSONEq(t, `{"status":"active"}`, string(b))
 
 		var d2 Data
 		err = json.Unmarshal([]byte(`{"status":"inactive"}`), &d2)

_examples/status/job_status_test.go

@@ -1,3 +1,4 @@
+// Package status provides examples of enum usage
 package status
 
 import (
@@ -27,7 +28,7 @@ func TestStatus(t *testing.T) {
 		d := Data{Status: StatusActive}
 		b, err := json.Marshal(d)
 		require.NoError(t, err)
-		assert.Equal(t, `{"status":"active"}`, string(b))
+		assert.JSONEq(t, `{"status":"active"}`, string(b))
 
 		var d2 Data
 		err = json.Unmarshal([]byte(`{"status":"inactive"}`), &d2)

_examples/status/status_enum.go

@@ -142,4 +142,16 @@ func {{.Type | title}}Iter() func(yield func({{.Type | title}}) bool) {
 			}
 		}
 	}
-}
+}
+
+// These variables are used to prevent the compiler from reporting unused errors
+// for the original enum constants. They are intentionally placed in a var block
+// that is compiled away by the Go compiler.
+var _ = func() bool {
+	var _ {{.Type}} = 0
+	{{range .Values -}}
+	// This avoids "defined but not used" linter error for {{.PrivateName}}
+	var _ {{$.Type}} = {{.PrivateName}}
+	{{end -}}
+	return true
+}()

_examples/status/status_test.go

@@ -478,6 +478,42 @@ const (
 	})
 }
 
+func TestNoLinterWarningsForUnusedConstants(t *testing.T) {
+	tmpDir := t.TempDir()
+	err := os.WriteFile(filepath.Join(tmpDir, "linter_test.go"), []byte(`
+package test
+type linterTest uint8
+const (
+	linterTestUnknown linterTest = iota
+	linterTestValue1
+	linterTestValue2
+)
+`), 0o644)
+	require.NoError(t, err)
+
+	gen, err := New("linterTest", tmpDir)
+	require.NoError(t, err)
+
+	err = gen.Parse(tmpDir)
+	require.NoError(t, err)
+
+	err = gen.Generate()
+	require.NoError(t, err)
+
+	// read the generated file to check for the linter warning prevention code
+	content, err := os.ReadFile(filepath.Join(tmpDir, "linter_test_enum.go"))
+	require.NoError(t, err)
+
+	// check that the unused constants prevention code exists
+	assert.Contains(t, string(content), "// These variables are used to prevent the compiler from reporting unused errors")
+	assert.Contains(t, string(content), "var _ = func() bool {")
+	assert.Contains(t, string(content), "var _ linterTest = 0")
+	assert.Contains(t, string(content), "var _ linterTest = linterTestUnknown")
+	assert.Contains(t, string(content), "var _ linterTest = linterTestValue1")
+	assert.Contains(t, string(content), "var _ linterTest = linterTestValue2")
+	assert.Contains(t, string(content), "return true")
+}
+
 func TestGeneratorEdgeCases(t *testing.T) {
 	t.Run("invalid template", func(t *testing.T) {
 		// create a generator with a broken template that will fail to execute