feat: add more clear error message and Environment info for template (#413)

* feat: add more clear error message and Environment info for template

Signed-off-by: yxxhero <aiopsclub@163.com>

* Update pkg/state/state.go

Co-authored-by: Yusuke Kuoka <ykuoka@gmail.com>
Signed-off-by: yxxhero <aiopsclub@163.com>

Signed-off-by: yxxhero <aiopsclub@163.com>
Co-authored-by: Yusuke Kuoka <ykuoka@gmail.com>

pkg/state/state.go

@@ -3200,7 +3200,7 @@ func (st *HelmState) GenerateOutputFilePath(release *ReleaseSpec, outputFileTemp
 
 	t, err := template.New("output-file").Parse(outputFileTemplate)
 	if err != nil {
-		return "", fmt.Errorf("parsing output-file template")
+		return "", fmt.Errorf("parsing output-file template %q: %w", outputFileTemplate, err)
 	}
 
 	buf := &bytes.Buffer{}
@@ -3213,8 +3213,9 @@ func (st *HelmState) GenerateOutputFilePath(release *ReleaseSpec, outputFileTemp
 	}
 
 	data := struct {
-		State   state
+		State       state
-		Release *ReleaseSpec
+		Release     *ReleaseSpec
+		Environment *environment.Environment
 	}{
 		State: state{
 			BaseName:    stateFileName,
@@ -3222,7 +3223,8 @@ func (st *HelmState) GenerateOutputFilePath(release *ReleaseSpec, outputFileTemp
 			AbsPath:     stateAbsPath,
 			AbsPathSHA1: sha1sum,
 		},
-		Release: release,
+		Release:     release,
+		Environment: &st.Env,
 	}
 
 	if err := t.Execute(buf, data); err != nil {

pkg/state/state_test.go

@@ -8,8 +8,10 @@ import (
 	"testing"
 
 	"github.com/Masterminds/semver/v3"
+	"github.com/stretchr/testify/require"
 	"github.com/variantdev/vals"
 
+	"github.com/helmfile/helmfile/pkg/environment"
 	"github.com/helmfile/helmfile/pkg/exectest"
 	"github.com/helmfile/helmfile/pkg/filesystem"
 	"github.com/helmfile/helmfile/pkg/helmexec"
@@ -2542,3 +2544,54 @@ func Test_gatherUsernamePassword(t *testing.T) {
 		})
 	}
 }
+
+func TestGenerateOutputFilePath(t *testing.T) {
+	tests := []struct {
+		envName            string
+		filePath           string
+		releaseName        string
+		outputFileTemplate string
+		wantErr            bool
+		expected           string
+	}{
+		{
+			envName:            "dev",
+			releaseName:        "release1",
+			filePath:           "/path/to/helmfile.yaml",
+			outputFileTemplate: "helmfile-{{ .Environment.Name }}.yaml",
+			expected:           "helmfile-dev.yaml",
+		},
+		{
+			envName:            "error",
+			releaseName:        "release2",
+			filePath:           "helmfile.yaml",
+			outputFileTemplate: "helmfile-{{ .Environment.Name",
+			wantErr:            true,
+			expected:           "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.envName, func(t *testing.T) {
+			st := &HelmState{
+				FilePath: tt.envName,
+				ReleaseSetSpec: ReleaseSetSpec{
+					Env: environment.Environment{
+						Name: tt.envName,
+					},
+				},
+			}
+			ra := &ReleaseSpec{
+				Name: tt.releaseName,
+			}
+			got, err := st.GenerateOutputFilePath(ra, tt.outputFileTemplate)
+
+			if tt.wantErr {
+				require.Errorf(t, err, "GenerateOutputFilePath() error = %v, want error", err)
+			} else {
+				require.NoError(t, err, "GenerateOutputFilePath() error = %v, want nil", err)
+			}
+			require.Equalf(t, got, tt.expected, "GenerateOutputFilePath() got = %v, want %v", got, tt.expected)
+		})
+	}
+}