feat: optionally allow missing environment values/secrets files (#620)

```yaml
environments:
  default:
    missingFileHandler: Warn
    values:
    - path/to/values.yaml
    secrets:
    - path/to/secrets.yaml
```

`missingFileHandler` set to `Warn`, `Info`, or `Debug` results in helmfile NOT stop when `path/to/values.yaml` or `path/to/secrets.yaml` is missing.

Resolves #548

While implementing the above feature, I also found a bug that has been causing #559. This also fixes that.

To verify it is actually fixed, create an example helmfile.yaml that looks like the below, and run `helmfile diff`:

```
$ cat helmfile.yaml
environments:
  default:
    secrets:
      - env-secrets.yaml

releases:
  - name: myapp
    chart: nginx
    namespace: default
    secrets: [secrets.yaml]    # Notice this file does not exist
    values:
      - ingress:
          enabled: true

$ helmfile diff
could not deduce `environment:` block, configuring only .Environment.Name. error: failed to read helmfile.yaml.part.0: environment values file matching "env-secrets.yaml" does not exist
in ./helmfile.yaml: failed to read helmfile.yaml: environment values file matching "env-secrets.yaml" does not exist
```

Fixes #559

README.md

@@ -30,6 +30,10 @@ To avoid upgrades for each iteration of `helm`, the `helmfile` executable delega
 The default helmfile is `helmfile.yaml`:
 
 ```yaml
+# Chart repositories used from within this state file
+#
+# Use `helm-s3` and `helm-git` and whatever Helm Downloader plugins
+# to use repositories other than the official repository or one backend by chartmuseum.
 repositories:
   - name: roboll
     url: http://roboll.io/charts
@@ -63,6 +67,9 @@ helmDefaults:
   # path to TLS key file (default "$HELM_HOME/key.pem")
   tlsKey: "path/to/key.pem"
 
+# The desired states of Helm releases.
+#
+# Helmfile runs various helm commands to converge the current state in the live cluster to the desired state defined here.
 releases:
   # Published chart example
   - name: vault                            # name of this release
@@ -71,7 +78,7 @@ releases:
       foo: bar
     chart: roboll/vault-secret-manager     # the chart being installed to create this release, referenced by `repository/chart` syntax
     version: ~1.24.1                       # the semver of the chart. range constraint is supported
-    missingFileHandler: warn # set to either "Error" or "Warn". "Error" instructs helmfile to fail when unable to find a values or secrets file. When "Warn", it prints the file and continues.
+    missingFileHandler: Warn # set to either "Error" or "Warn". "Error" instructs helmfile to fail when unable to find a values or secrets file. When "Warn", it prints the file and continues.
     values:
       # value files passed via --values
       - vault.yaml
@@ -134,6 +141,43 @@ releases:
     - ./values/{{ requiredEnv "PLATFORM_ENV" }}/config.yaml # Values file taken from path with environment variable. $PLATFORM_ENV must be set in the calling environment.
     wait: true
 
+#
+# Advanced Configuration: Helmfile Environments
+#
+
+# The list of environments managed by helmfile.
+#
+# The default is `environments: {"default": {}}` which implies:
+#
+# - `{{ .Environment.Name }}` evaluates to "default"
+# - `{{ .Environment.Values }}` being empty
+environments:
+  # The "default" environment is available and used when `helmfile` is run without `--environment NAME`.
+  default:
+    # Everything from the values.yaml is available via `{{ .Environment.Values.KEY }}`.
+    # Suppose `{"foo": {"bar": 1}}` contained in the values.yaml below,
+    # `{{ .Environment.Values.foo.bar }}` is evaluated to `1`.
+    values:
+    - environments/default/values.yaml
+  # Any environment other than `default` is used only when `helmfile` is run with `--environment NAME`.
+  # That is, the "production" env below is used when and only when it is run like `helmfile --environment production sync`.
+  production:
+    values:
+    - environment/production/values.yaml
+    ## `secrets.yaml` is decrypted by `helm-secrets` and available via `{{ .Environment.Secrets.KEY }}`
+    secrets:
+    - environment/production/secrets.yaml
+    # Overrides the `environmentDefaults.missingFileHandler` for this environment 
+    missingFileHandler: Error
+
+environmentDefaults:
+  # Instructs helmfile to fail when unable to find a environment values file listed under `environments.NAME.values`.
+  #
+  # Possible values are  "Error", "Warn", "Info", "Debug". The default is "Error".
+  #
+  # Use "Warn", "Info", or "Debug" if you want helmfile to not fail when a values file is missing, while just leaving
+  # a message about the missing file at the log-level.
+  missingFileHandler: Error
 ```
 
 ## Templating

pkg/app/app.go

@@ -26,6 +26,7 @@ type App struct {
 	Selectors   []string
 
 	readFile          func(string) ([]byte, error)
+	fileExists        func(string) (bool, error)
 	glob              func(string) ([]string, error)
 	abs               func(string) (string, error)
 	fileExistsAt      func(string) bool
@@ -42,6 +43,7 @@ func Init(app *App) *App {
 	app.getwd = os.Getwd
 	app.chdir = os.Chdir
 	app.fileExistsAt = fileExistsAt
+	app.fileExists = fileExists
 	app.directoryExistsAt = directoryExistsAt
 	return app
 }
@@ -114,6 +116,7 @@ func (a *App) visitStateFiles(fileOrDir string, do func(string) error) error {
 func (a *App) loadDesiredStateFromYaml(file string) (*state.HelmState, error) {
 	ld := &desiredStateLoader{
 		readFile:   a.readFile,
+		fileExists: a.fileExists,
 		env:        a.Env,
 		namespace:  a.Namespace,
 		logger:     a.Logger,
@@ -316,6 +319,18 @@ func fileExistsAt(path string) bool {
 	return err == nil && fileInfo.Mode().IsRegular()
 }
 
+func fileExists(path string) (bool, error) {
+	_, err := os.Stat(path)
+
+	if err != nil {
+		if os.IsNotExist(err) {
+			return false, nil
+		}
+		return false, err
+	}
+	return true, nil
+}
+
 func directoryExistsAt(path string) bool {
 	fileInfo, err := os.Stat(path)
 	return err == nil && fileInfo.Mode().IsDir()

pkg/app/app_test.go

@@ -24,6 +24,7 @@ func injectFs(app *App, fs *state.TestFs) *App {
 	app.getwd = fs.Getwd
 	app.chdir = fs.Chdir
 	app.fileExistsAt = fs.FileExistsAt
+	app.fileExists = fs.FileExists
 	app.directoryExistsAt = fs.DirectoryExistsAt
 	return app
 }
@@ -155,12 +156,66 @@ releases:
 		t.Fatal("expected error did not occur")
 	}
 
-	expected := "in ./helmfile.yaml: failed to read helmfile.yaml: no file matching env.*.yaml found"
+	expected := "in ./helmfile.yaml: failed to read helmfile.yaml: environment values file matching \"env.*.yaml\" does not exist"
 	if err.Error() != expected {
 		t.Errorf("unexpected error: expected=%s, got=%v", expected, err)
 	}
 }
 
+func TestVisitDesiredStatesWithReleasesFiltered_MissingEnvValuesFileHandler(t *testing.T) {
+	testcases := []struct {
+		name        string
+		handler     string
+		filePattern string
+		expectErr   bool
+	}{
+		{name: "error handler with no files matching glob", handler: "Error", filePattern: "env.*.yaml", expectErr: true},
+		{name: "warn handler with no files matching glob", handler: "Warn", filePattern: "env.*.yaml", expectErr: false},
+		{name: "info handler with no files matching glob", handler: "Info", filePattern: "env.*.yaml", expectErr: false},
+		{name: "debug handler with no files matching glob", handler: "Debug", filePattern: "env.*.yaml", expectErr: false},
+	}
+
+	for i := range testcases {
+		testcase := testcases[i]
+		t.Run(testcase.name, func(t *testing.T) {
+			files := map[string]string{
+				"/path/to/helmfile.yaml": fmt.Sprintf(`
+environments:
+  default:
+    missingFileHandler: %s
+    values:
+    - %s
+releases:
+- name: zipkin
+  chart: stable/zipkin
+`, testcase.handler, testcase.filePattern),
+			}
+			fs := state.NewTestFs(files)
+			app := &App{
+				KubeContext: "default",
+				Logger:      helmexec.NewLogger(os.Stderr, "debug"),
+				Namespace:   "",
+				Env:         "default",
+			}
+			app = injectFs(app, fs)
+			noop := func(st *state.HelmState, helm helmexec.Interface) []error {
+				return []error{}
+			}
+
+			err := app.VisitDesiredStatesWithReleasesFiltered(
+				"helmfile.yaml", noop,
+			)
+			if testcase.expectErr && err == nil {
+				t.Fatal("expected error did not occur")
+			}
+
+			if !testcase.expectErr && err != nil {
+				t.Errorf("not error expected, but got: %v", err)
+			}
+		})
+	}
+}
+
 // See https://github.com/roboll/helmfile/issues/193
 func TestVisitDesiredStatesWithReleasesFiltered(t *testing.T) {
 	files := map[string]string{
@@ -749,13 +804,15 @@ helmDefaults:
 		readFile:     testFs.ReadFile,
 		glob:         testFs.Glob,
 		abs:          testFs.Abs,
+		fileExistsAt: testFs.FileExistsAt,
+		fileExists:   testFs.FileExists,
 		KubeContext:  "default",
 		Env:          "default",
 		Logger:       helmexec.NewLogger(os.Stderr, "debug"),
 	}
 	st, err := app.loadDesiredStateFromYaml(yamlFile)
 	if err != nil {
-		t.Errorf("unexpected error: %v", err)
+		t.Fatalf("unexpected error: %v", err)
 	}
 
 	if st.HelmDefaults.TillerNamespace != "TILLER_NS" {
@@ -826,6 +883,7 @@ helmDefaults:
 	})
 	app := &App{
 		readFile:   testFs.ReadFile,
+		fileExists: testFs.FileExists,
 		glob:       testFs.Glob,
 		abs:        testFs.Abs,
 		Env:        "default",
@@ -901,6 +959,7 @@ foo: FOO
 	})
 	app := &App{
 		readFile:   testFs.ReadFile,
+		fileExists: testFs.FileExists,
 		glob:       testFs.Glob,
 		abs:        testFs.Abs,
 		Env:        "default",
@@ -979,6 +1038,7 @@ helmDefaults:
 	})
 	app := &App{
 		readFile:   testFs.ReadFile,
+		fileExists: testFs.FileExists,
 		glob:       testFs.Glob,
 		abs:        testFs.Abs,
 		Env:        "test",

pkg/app/desired_state_file_loader.go

@@ -20,6 +20,7 @@ type desiredStateLoader struct {
 	namespace string
 
 	readFile   func(string) ([]byte, error)
+	fileExists func(string) (bool, error)
 	abs        func(string) (string, error)
 	glob       func(string) ([]string, error)
 
@@ -96,7 +97,7 @@ func (ld *desiredStateLoader) loadFile(inheritedEnv *environment.Environment, ba
 }
 
 func (a *desiredStateLoader) underlying() *state.StateCreator {
-	c := state.NewCreator(a.logger, a.readFile, a.abs, a.glob)
+	c := state.NewCreator(a.logger, a.readFile, a.fileExists, a.abs, a.glob)
 	c.LoadFile = a.loadFile
 	return c
 }
@@ -109,10 +110,13 @@ func (a *desiredStateLoader) load(yaml []byte, baseDir, file string, evaluateBas
 
 	helmfiles := []state.SubHelmfileSpec{}
 	for _, hf := range st.Helmfiles {
-		matches, err := st.ExpandPaths([]string{hf.Path}, a.glob)
+		matches, err := st.ExpandPaths(hf.Path)
 		if err != nil {
 			return nil, err
 		}
+		if len(matches) == 0 {
+			return nil, fmt.Errorf("no file matching %s found", hf.Path)
+		}
 		for _, match := range matches {
 			newHelmfile := hf
 			newHelmfile.Path = match

pkg/app/two_pass_renderer_test.go

@@ -17,6 +17,7 @@ func makeLoader(files map[string]string, env string) (*desiredStateLoader, *stat
 		namespace:  "namespace",
 		logger:     helmexec.NewLogger(os.Stdout, "debug"),
 		readFile:   testfs.ReadFile,
+		fileExists: testfs.FileExists,
 		abs:        testfs.Abs,
 		glob:       testfs.Glob,
 	}, testfs

state/create.go

@@ -37,6 +37,7 @@ func (e *UndefinedEnvError) Error() string {
 type StateCreator struct {
 	logger     *zap.SugaredLogger
 	readFile   func(string) ([]byte, error)
+	fileExists func(string) (bool, error)
 	abs        func(string) (string, error)
 	glob       func(string) ([]string, error)
 
@@ -45,10 +46,11 @@ type StateCreator struct {
 	LoadFile func(inheritedEnv *environment.Environment, baseDir, file string, evaluateBases bool) (*HelmState, error)
 }
 
-func NewCreator(logger *zap.SugaredLogger, readFile func(string) ([]byte, error), abs func(string) (string, error), glob func(string) ([]string, error)) *StateCreator {
+func NewCreator(logger *zap.SugaredLogger, readFile func(string) ([]byte, error), fileExists func(string) (bool, error), abs func(string) (string, error), glob func(string) ([]string, error)) *StateCreator {
 	return &StateCreator{
 		logger:     logger,
 		readFile:   readFile,
+		fileExists: fileExists,
 		abs:        abs,
 		glob:       glob,
 		Strict:     true,
@@ -102,17 +104,8 @@ func (c *StateCreator) Parse(content []byte, baseDir, file string) (*HelmState,
 
 	state.readFile = c.readFile
 	state.removeFile = os.Remove
-	state.fileExists = func(path string) (bool, error) {
+	state.fileExists = c.fileExists
-		_, err := os.Stat(path)
+	state.glob = c.glob
-
-		if err != nil {
-			if os.IsNotExist(err) {
-				return false, nil
-			}
-			return false, err
-		}
-		return true, nil
-	}
 
 	return &state, nil
 }
@@ -171,28 +164,17 @@ func (c *StateCreator) loadBases(envValues *environment.Environment, st *HelmSta
 	return layers[0], nil
 }
 
-func (st *HelmState) ExpandPaths(patterns []string, glob func(string) ([]string, error)) ([]string, error) {
+func (st *HelmState) ExpandPaths(globPattern string) ([]string, error) {
 	result := []string{}
-	for _, globPattern := range patterns {
+	absPathPattern := st.normalizePath(globPattern)
-		var absPathPattern string
+	matches, err := st.glob(absPathPattern)
-		if filepath.IsAbs(globPattern) {
-			absPathPattern = globPattern
-		} else {
-			absPathPattern = st.JoinBase(globPattern)
-		}
-		matches, err := glob(absPathPattern)
 	if err != nil {
 		return nil, fmt.Errorf("failed processing %s: %v", globPattern, err)
 	}
 
-		if len(matches) == 0 {
-			return nil, fmt.Errorf("no file matching %s found", globPattern)
-		}
-
 	sort.Strings(matches)
 
 	result = append(result, matches...)
-	}
 	return result, nil
 }
 
@@ -200,12 +182,20 @@ func (st *HelmState) loadEnvValues(name string, ctxEnv *environment.Environment,
 	envVals := map[string]interface{}{}
 	envSpec, ok := st.Environments[name]
 	if ok {
-		valuesFiles, err := st.ExpandPaths(envSpec.Values, glob)
+		var envValuesFiles []string
+		for _, urlOrPath := range envSpec.Values {
+			resolved, skipped, err := st.resolveFile(envSpec.MissingFileHandler, "environment values", urlOrPath)
 			if err != nil {
 				return nil, err
 			}
+			if skipped {
+				continue
+			}
 
-		for _, envvalFullPath := range valuesFiles {
+			envValuesFiles = append(envValuesFiles, resolved...)
+		}
+
+		for _, envvalFullPath := range envValuesFiles {
 			tmplData := EnvironmentTemplateData{Environment: environment.EmptyEnvironment, Namespace: ""}
 			r := tmpl.NewFileRenderer(readFile, filepath.Dir(envvalFullPath), tmplData)
 			bytes, err := r.RenderToBytes(envvalFullPath)
@@ -222,16 +212,22 @@ func (st *HelmState) loadEnvValues(name string, ctxEnv *environment.Environment,
 		}
 
 		if len(envSpec.Secrets) > 0 {
-			secretsFiles, err := st.ExpandPaths(envSpec.Secrets, glob)
+			helm := helmexec.New(st.logger, "")
+
+			var envSecretFiles []string
+			for _, urlOrPath := range envSpec.Secrets {
+				resolved, skipped, err := st.resolveFile(envSpec.MissingFileHandler, "environment values", urlOrPath)
 				if err != nil {
 					return nil, err
 				}
-
+				if skipped {
-			helm := helmexec.New(st.logger, "")
+					continue
-			for _, path := range secretsFiles {
-				if _, err := os.Stat(path); os.IsNotExist(err) {
-					return nil, err
 				}
+
+				envSecretFiles = append(envSecretFiles, resolved...)
+			}
+
+			for _, path := range envSecretFiles {
 				// Work-around to allow decrypting environment secrets
 				//
 				// We don't have releases loaded yet and therefore unable to decide whether

state/create_test.go

@@ -106,7 +106,7 @@ bar: {{ readFile "bar.txt" }}
 	})
 	testFs.Cwd = "/example/path/to"
 
-	state, err := NewCreator(logger, testFs.ReadFile, testFs.Abs, testFs.Glob).ParseAndLoad(yamlContent, filepath.Dir(yamlFile), yamlFile, "production", false, nil)
+	state, err := NewCreator(logger, testFs.ReadFile, testFs.FileExists, testFs.Abs, testFs.Glob).ParseAndLoad(yamlContent, filepath.Dir(yamlFile), yamlFile, "production", false, nil)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}

state/environment.go

@@ -3,4 +3,13 @@ package state
 type EnvironmentSpec struct {
 	Values  []string `yaml:"values"`
 	Secrets []string `yaml:"secrets"`
+
+	// MissingFileHandler instructs helmfile to fail when unable to find a environment values file listed
+	// under `environments.NAME.values`.
+	//
+	// Possible values are  "Error", "Warn", "Info", "Debug". The default is "Error".
+	//
+	// Use "Warn", "Info", or "Debug" if you want helmfile to not fail when a values file is missing, while just leaving
+	// a message about the missing file at the log-level.
+	MissingFileHandler *string `yaml:"missingFileHandler"`
 }

state/state.go

@@ -28,9 +28,10 @@ import (
 // HelmState structure for the helmfile
 type HelmState struct {
 	basePath string
-	Environments map[string]EnvironmentSpec
 	FilePath string
 
+	Environments map[string]EnvironmentSpec `yaml:"environments"`
+
 	Bases              []string          `yaml:"bases"`
 	HelmDefaults       HelmSpec          `yaml:"helmDefaults"`
 	Helmfiles          []SubHelmfileSpec `yaml:"helmfiles"`
@@ -51,6 +52,7 @@ type HelmState struct {
 
 	removeFile func(string) error
 	fileExists func(string) (bool, error)
+	glob       func(string) ([]string, error)
 	tempDir    func(string, string) (string, error)
 
 	runner helmexec.Runner
@@ -171,6 +173,11 @@ type AffectedReleases struct {
 
 const DefaultEnv = "default"
 
+const MissingFileHandlerError = "Error"
+const MissingFileHandlerInfo = "Info"
+const MissingFileHandlerWarn = "Warn"
+const MissingFileHandlerDebug = "Debug"
+
 func (st *HelmState) applyDefaultsTo(spec *ReleaseSpec) {
 	if st.Namespace != "" {
 		spec.Namespace = st.Namespace
@@ -1252,26 +1259,18 @@ func (st *HelmState) generateTemporaryValuesFiles(values []interface{}, missingF
 	for _, value := range values {
 		switch typedValue := value.(type) {
 		case string:
-			path := st.normalizePath(typedValue)
+			paths, skip, err := st.resolveFile(missingFileHandler, "values", typedValue)
-
-			ok, err := st.fileExists(path)
 			if err != nil {
 				return nil, err
 			}
-			if !ok {
+			if skip {
-				if missingFileHandler == nil || *missingFileHandler == "Error" {
-					return nil, fmt.Errorf("file does not exist: %s", path)
-				} else if *missingFileHandler == "Warn" {
-					st.logger.Warnf("skipping missing values file \"%s\"", path)
-					continue
-				} else if *missingFileHandler == "Info" {
-					st.logger.Infof("skipping missing values file \"%s\"", path)
-					continue
-				} else {
-					st.logger.Debugf("skipping missing values file \"%s\"", path)
 				continue
 			}
+
+			if len(paths) > 1 {
+				return nil, fmt.Errorf("glob patterns in release values and secrets is not supported yet. please submit a feature request if necessary")
 			}
+			path := paths[0]
 
 			yamlBytes, err := st.RenderValuesFileToBytes(path)
 			if err != nil {
@@ -1337,25 +1336,18 @@ func (st *HelmState) namespaceAndValuesFlags(helm helmexec.Interface, release *R
 	release.generatedValues = append(release.generatedValues, generatedFiles...)
 
 	for _, value := range release.Secrets {
-		path := st.normalizePath(release.ValuesPathPrefix + value)
+		paths, skip, err := st.resolveFile(release.MissingFileHandler, "secrets", release.ValuesPathPrefix+value)
-		ok, err := st.fileExists(path)
 		if err != nil {
 			return nil, err
 		}
-		if !ok {
+		if skip {
-			if release.MissingFileHandler == nil || *release.MissingFileHandler == "Error" {
-				return nil, err
-			} else if *release.MissingFileHandler == "Warn" {
-				st.logger.Warnf("skipping missing secrets file \"%s\"", path)
-				continue
-			} else if *release.MissingFileHandler == "Info" {
-				st.logger.Infof("skipping missing secrets file \"%s\"", path)
-				continue
-			} else {
-				st.logger.Debugf("skipping missing secrets file \"%s\"", path)
 			continue
 		}
+
+		if len(paths) > 1 {
+			return nil, fmt.Errorf("glob patterns in release secret file is not supported yet. please submit a feature request if necessary")
 		}
+		path := paths[0]
 
 		decryptFlags := st.appendTillerFlags([]string{}, release)
 		valfile, err := helm.DecryptSecret(st.createHelmContext(release, workerIndex), path, decryptFlags...)
@@ -1413,6 +1405,49 @@ func (st *HelmState) namespaceAndValuesFlags(helm helmexec.Interface, release *R
 	return flags, nil
 }
 
+func (st *HelmState) resolveFile(missingFileHandler *string, tpe, path string) ([]string, bool, error) {
+	title := fmt.Sprintf("%s file", tpe)
+
+	files, err := st.ExpandPaths(path)
+	if err != nil {
+		return nil, false, err
+	}
+
+	var handlerId string
+
+	if missingFileHandler != nil {
+		handlerId = *missingFileHandler
+	} else {
+		handlerId = MissingFileHandlerError
+	}
+
+	if len(files) == 0 {
+		switch handlerId {
+		case MissingFileHandlerError:
+			return nil, false, fmt.Errorf("%s matching \"%s\" does not exist", title, path)
+		case MissingFileHandlerWarn:
+			st.logger.Warnf("skipping missing %s matching \"%s\"", title, path)
+			return nil, true, nil
+		case MissingFileHandlerInfo:
+			st.logger.Infof("skipping missing %s matching \"%s\"", title, path)
+			return nil, true, nil
+		case MissingFileHandlerDebug:
+			st.logger.Debugf("skipping missing %s matching \"%s\"", title, path)
+			return nil, true, nil
+		default:
+			available := []string{
+				MissingFileHandlerError,
+				MissingFileHandlerWarn,
+				MissingFileHandlerInfo,
+				MissingFileHandlerDebug,
+			}
+			return nil, false, fmt.Errorf("invalid missing file handler \"%s\" while processing \"%s\" in \"%s\": it must be one of %s", handlerId, path, st.FilePath, available)
+		}
+	}
+
+	return files, false, nil
+}
+
 // DisplayAffectedReleases logs the upgraded, deleted and in error releases
 func (ar *AffectedReleases) DisplayAffectedReleases(logger *zap.SugaredLogger) {
 	if ar.Upgraded != nil {

state/state_test.go

@@ -17,6 +17,7 @@ import (
 var logger = helmexec.NewLogger(os.Stdout, "warn")
 
 func injectFs(st *HelmState, fs *TestFs) *HelmState {
+	st.glob = fs.Glob
 	st.readFile = fs.ReadFile
 	st.fileExists = fs.FileExists
 	return st
@@ -1000,7 +1001,7 @@ func TestHelmState_SyncReleases_MissingValuesFileForUndesiredRelease(t *testing.
 				Values: []interface{}{"noexistent.values.yaml"},
 			},
 			listResult:    ``,
-			expectedError: `failed processing release foo: file does not exist: noexistent.values.yaml`,
+			expectedError: `failed processing release foo: values file matching "noexistent.values.yaml" does not exist`,
 		},
 		{
 			name: "should fail upgrading due to missing values file",
@@ -1011,7 +1012,7 @@ func TestHelmState_SyncReleases_MissingValuesFileForUndesiredRelease(t *testing.
 			},
 			listResult: `NAME 	REVISION	UPDATED                 	STATUS  	CHART                      	APP VERSION	NAMESPACE
 										foo	1       	Wed Apr 17 17:39:04 2019	DEPLOYED	foo-bar-2.0.4	0.1.0      	default`,
-			expectedError: `failed processing release foo: file does not exist: noexistent.values.yaml`,
+			expectedError: `failed processing release foo: values file matching "noexistent.values.yaml" does not exist`,
 		},
 		{
 			name: "should uninstall even when there is a missing values file",
@@ -1427,22 +1428,15 @@ func TestHelmState_SyncReleasesCleanup(t *testing.T) {
 			state := &HelmState{
 				Releases: tt.releases,
 				logger:   logger,
-				readFile: func(f string) ([]byte, error) {
-					if f != "someFile" {
-						return nil, fmt.Errorf("unexpected file to read: %s", f)
-					}
-					someFileContent := []byte(`foo: bar
-`)
-					return someFileContent, nil
-				},
 				removeFile: func(f string) error {
 					numRemovedFiles += 1
 					return nil
 				},
-				fileExists: func(f string) (bool, error) {
-					return true, nil
-				},
 			}
+			testfs := NewTestFs(map[string]string{
+				"/path/to/someFile": `foo: FOO`,
+			})
+			state = injectFs(state, testfs)
 			if errs := state.SyncReleases(&AffectedReleases{}, tt.helm, []string{}, 1); errs != nil && len(errs) > 0 {
 				t.Errorf("unexpected errors: %v", errs)
 			}
@@ -1517,22 +1511,16 @@ func TestHelmState_DiffReleasesCleanup(t *testing.T) {
 			state := &HelmState{
 				Releases: tt.releases,
 				logger:   logger,
-				readFile: func(f string) ([]byte, error) {
-					if f != "someFile" {
-						return nil, fmt.Errorf("unexpected file to read: %s", f)
-					}
-					someFileContent := []byte(`foo: bar
-`)
-					return someFileContent, nil
-				},
 				removeFile: func(f string) error {
 					numRemovedFiles += 1
 					return nil
 				},
-				fileExists: func(f string) (bool, error) {
-					return true, nil
-				},
 			}
+			testfs := NewTestFs(map[string]string{
+				"/path/to/someFile": `foo: bar
+`,
+			})
+			state = injectFs(state, testfs)
 			if _, errs := state.DiffReleases(tt.helm, []string{}, 1, false, false, false); errs != nil && len(errs) > 0 {
 				t.Errorf("unexpected errors: %v", errs)
 			}