feat: add --skip-charts flag to build command

Add a --skip-charts flag to the `helmfile build` command to allow users
to skip chart preparation, following the same pattern as the list and
destroy commands.

This addresses an issue where `helmfile build` would run `helm template`
on kustomize resources during chart preparation, even though build is
meant to be a read-only inspection command.

Changes:
- Add SkipCharts field to BuildOptions
- Add --skip-charts flag to build command CLI
- Update StateConfigProvider interface to include SkipCharts()
- Update PrintState() to conditionally skip withPreparedCharts when flag is set

By default, the flag is false (charts are prepared) to maintain backward
compatibility. Users can now run `helmfile build --skip-charts` to get
fast output without chart preparation.

Signed-off-by: Shane Starcher <shanestarcher@gmail.com>

cmd/build.go

@@ -32,6 +32,7 @@ func NewBuildCmd(globalCfg *config.GlobalImpl) *cobra.Command {
 
 	f := cmd.Flags()
 	f.BoolVar(&buildOptions.EmbedValues, "embed-values", false, "Read all the values files for every release and embed into the output helmfile.yaml")
+	f.BoolVar(&buildOptions.SkipCharts, "skip-charts", false, "don't prepare charts when building releases")
 
 	return cmd
 }

pkg/app/app.go

@@ -521,11 +521,7 @@ func (a *App) PrintDAGState(c DAGConfigProvider) error {
 
 func (a *App) PrintState(c StateConfigProvider) error {
 	return a.ForEachState(func(run *Run) (_ bool, errs []error) {
-		err := run.withPreparedCharts("build", state.ChartPrepareOptions{
-			SkipRepos:   true,
-			SkipDeps:    true,
-			Concurrency: 2,
-		}, func() {
+		printState := func() {
 			if c.EmbedValues() {
 				for i := range run.state.Releases {
 					r := run.state.Releases[i]
@@ -562,13 +558,22 @@ func (a *App) PrintState(c StateConfigProvider) error {
 			fmt.Printf("---\n#  Source: %s\n\n%+v", sourceFile, stateYaml)
 
 			errs = []error{}
-		})
-
-		if err != nil {
-			errs = append(errs, err)
 		}
 
-		return
+		if !c.SkipCharts() {
+			err := run.withPreparedCharts("build", state.ChartPrepareOptions{
+				SkipRepos:   true,
+				SkipDeps:    true,
+				Concurrency: 2,
+			}, printState)
+			if err != nil {
+				errs = append(errs, err)
+			}
+		} else {
+			printState()
+		}
+
+		return false, errs
 	}, false, SetFilter(true))
 }
 
@@ -592,20 +597,22 @@ func (a *App) ListReleases(c ListConfigProvider) error {
 		var stateReleases []*HelmRelease
 		var err error
 
+		listReleases := func() {
+			rel, err := a.list(run)
+			if err != nil {
+				panic(err)
+			}
+			stateReleases = rel
+		}
+
 		if !c.SkipCharts() {
 			err = run.withPreparedCharts("list", state.ChartPrepareOptions{
 				SkipRepos:   true,
 				SkipDeps:    true,
 				Concurrency: 2,
-			}, func() {
-				rel, err := a.list(run)
-				if err != nil {
-					panic(err)
-				}
-				stateReleases = rel
-			})
+			}, listReleases)
 		} else {
-			stateReleases, err = a.list(run)
+			listReleases()
 		}
 
 		if err != nil {

pkg/app/config.go

@@ -264,6 +264,7 @@ type StatusesConfigProvider interface {
 
 type StateConfigProvider interface {
 	EmbedValues() bool
+	SkipCharts() bool
 }
 
 type DAGConfigProvider any

pkg/config/build.go

@@ -4,6 +4,8 @@ package config
 type BuildOptions struct {
 	// EmbedValues is true if the values should be embedded
 	EmbedValues bool
+	// SkipCharts makes Build skip `withPreparedCharts`
+	SkipCharts bool
 }
 
 // NewBuildOptions creates a new Apply
@@ -29,3 +31,8 @@ func NewBuildImpl(g *GlobalImpl, b *BuildOptions) *BuildImpl {
 func (b *BuildImpl) EmbedValues() bool {
 	return b.BuildOptions.EmbedValues
 }
+
+// SkipCharts returns skipCharts flag
+func (b *BuildImpl) SkipCharts() bool {
+	return b.BuildOptions.SkipCharts
+}