Avoid --skip-refresh on local charts (#541)

All the dependencies get correctly installed when dealing with remote
charts.

If there's a local chart that depends on remote dependencies then those
don't get automatically installed. See #526. They end up with this
error:

```
Error: no cached repository for helm-manager-b6cf96b91af4f01317d185adfbe32610179e5246214be9646a52cb0b86032272 found. (try 'helm repo update'): open /root/.cache/helm/repository/helm-manager-b6cf96b91af4f01317d185adfbe32610179e5246214be9646a52cb0b86032272-index.yaml: no such file or directory
```

One workaround for that would be to add the repositories from the local
charts. Something like this:

```
cd local-chart/ && helm dependency list $dir 2> /dev/null | tail +2 | head -n -1 | awk '{ print "helm repo add " $1 " " $3 }' | while read cmd; do $cmd; done
```

This however is not trivial to parse and implement.

An easier fix which I did here is just to not allow doing
`--skip-refresh` for local repositories.

Fixes #526

Signed-off-by: Indrek Juhkam <indrek@urgas.eu>

Signed-off-by: Indrek Juhkam <indrek@urgas.eu>

pkg/helmexec/exec.go

@@ -216,7 +216,7 @@ func (helm *execer) RegistryLogin(repository string, username string, password s
 	return err
 }
 
-func (helm *execer) BuildDeps(name, chart string) error {
+func (helm *execer) BuildDeps(name, chart string, flags ...string) error {
 	helm.logger.Infof("Building dependency release=%v, chart=%v", name, chart)
 	args := []string{
 		"dependency",
@@ -224,9 +224,7 @@ func (helm *execer) BuildDeps(name, chart string) error {
 		chart,
 	}
 
-	if helm.IsHelm3() {
-		args = append(args, "--skip-refresh")
-	}
+	args = append(args, flags...)
 
 	out, err := helm.exec(args, map[string]string{}, nil)
 	helm.info(out)

pkg/helmexec/exec_test.go

@@ -339,7 +339,7 @@ func Test_BuildDeps(t *testing.T) {
 	logger := NewLogger(&buffer, "debug")
 	helm3Runner := mockRunner{output: []byte("v3.2.4+ge29ce2a")}
 	helm := New("helm", false, logger, "dev", &helm3Runner)
-	err := helm.BuildDeps("foo", "./chart/foo")
+	err := helm.BuildDeps("foo", "./chart/foo", []string{"--skip-refresh"}...)
 	expected := `Building dependency release=foo, chart=./chart/foo
 exec: helm --kube-context dev dependency build ./chart/foo --skip-refresh
 v3.2.4+ge29ce2a
@@ -352,9 +352,22 @@ v3.2.4+ge29ce2a
 	}
 
 	buffer.Reset()
-	helm.SetExtraArgs("--verify")
 	err = helm.BuildDeps("foo", "./chart/foo")
 	expected = `Building dependency release=foo, chart=./chart/foo
+exec: helm --kube-context dev dependency build ./chart/foo
+v3.2.4+ge29ce2a
+`
+	if err != nil {
+		t.Errorf("unexpected error: %v", err)
+	}
+	if buffer.String() != expected {
+		t.Errorf("helmexec.BuildDeps()\nactual = %v\nexpect = %v", buffer.String(), expected)
+	}
+
+	buffer.Reset()
+	helm.SetExtraArgs("--verify")
+	err = helm.BuildDeps("foo", "./chart/foo", []string{"--skip-refresh"}...)
+	expected = `Building dependency release=foo, chart=./chart/foo
 exec: helm --kube-context dev dependency build ./chart/foo --skip-refresh --verify
 v3.2.4+ge29ce2a
 `

pkg/helmexec/helmexec.go

@@ -18,7 +18,7 @@ type Interface interface {
 	AddRepo(name, repository, cafile, certfile, keyfile, username, password string, managed string, passCredentials string, skipTLSVerify string) error
 	UpdateRepo() error
 	RegistryLogin(name string, username string, password string) error
-	BuildDeps(name, chart string) error
+	BuildDeps(name, chart string, flags ...string) error
 	UpdateDeps(chart string) error
 	SyncRelease(context HelmContext, name, chart string, flags ...string) error
 	DiffRelease(context HelmContext, name, chart string, suppressDiff bool, flags ...string) error