Add the SyncArgs option and --sync-args flag (#1375)

* add the SyncArgs option

Signed-off-by: Tim Ramlot <42113979+inteon@users.noreply.github.com>

* add syncArgs to helmDefaults and update index.md

Signed-off-by: Tim Ramlot <42113979+inteon@users.noreply.github.com>

* add --sync-args flags to helmfile sync

Signed-off-by: Tim Ramlot <42113979+inteon@users.noreply.github.com>

* add tests for appendExtraDiffFlags and appendExtraSyncFlags

Signed-off-by: Tim Ramlot <42113979+inteon@users.noreply.github.com>

---------

Signed-off-by: Tim Ramlot <42113979+inteon@users.noreply.github.com>

pkg/app/app.go

@@ -1476,6 +1476,7 @@ Do you really want to apply?
 					ResetValues:      c.ResetValues(),
 					PostRenderer:     c.PostRenderer(),
 					PostRendererArgs: c.PostRendererArgs(),
+					SyncArgs:         c.SyncArgs(),
 				}
 				return subst.SyncReleases(&affectedReleases, helm, c.Values(), c.Concurrency(), syncOpts)
 			}))
@@ -1869,6 +1870,7 @@ Do you really want to sync?
 					ResetValues:      c.ResetValues(),
 					PostRenderer:     c.PostRenderer(),
 					PostRendererArgs: c.PostRendererArgs(),
+					SyncArgs:         c.SyncArgs(),
 				}
 				return subst.SyncReleases(&affectedReleases, helm, c.Values(), c.Concurrency(), opts)
 			}))

pkg/app/app_test.go

@@ -2220,6 +2220,7 @@ type applyConfig struct {
 	stripTrailingCR         bool
 	interactive             bool
 	skipDiffOnInstall       bool
+	syncArgs                string
 	diffArgs                string
 	logger                  *zap.SugaredLogger
 	wait                    bool
@@ -2356,6 +2357,10 @@ func (a applyConfig) SkipDiffOnInstall() bool {
 	return a.skipDiffOnInstall
 }
 
+func (a applyConfig) SyncArgs() string {
+	return a.syncArgs
+}
+
 func (a applyConfig) DiffArgs() string {
 	return a.diffArgs
 }

pkg/app/config.go

@@ -83,6 +83,7 @@ type ApplyConfigProvider interface {
 	SkipDiffOnInstall() bool
 
 	DiffArgs() string
+	SyncArgs() string
 
 	DAGConfig
 
@@ -104,6 +105,7 @@ type SyncConfigProvider interface {
 	SkipDeps() bool
 	Wait() bool
 	WaitForJobs() bool
+	SyncArgs() string
 
 	Validate() bool