fix(helm): filter helm list to print latest release

`helm list` should only list latest release

fixes helm#3208

cmd/helm/list.go

@@ -156,7 +156,7 @@ func (l *listCmd) run() error {
 		fmt.Fprintf(l.out, "\tnext: %s\n", res.Next)
 	}
 
-	rels := res.Releases
+	rels := filterList(res.Releases)
 
 	if l.short {
 		for _, r := range rels {
@@ -168,6 +168,30 @@ func (l *listCmd) run() error {
 	return nil
 }
 
+// filterList returns a list scrubbed of old releases.
+func filterList(rels []*release.Release) []*release.Release {
+	idx := map[string]int32{}
+
+	for _, r := range rels {
+		name, version := r.GetName(), r.GetVersion()
+		if max, ok := idx[name]; ok {
+			// check if we have a greater version already
+			if max > version {
+				continue
+			}
+		}
+		idx[name] = version
+	}
+
+	uniq := make([]*release.Release, 0, len(idx))
+	for _, r := range rels {
+		if idx[r.GetName()] == r.GetVersion() {
+			uniq = append(uniq, r)
+		}
+	}
+	return uniq
+}
+
 // statusCodes gets the list of status codes that are to be included in the results.
 func (l *listCmd) statusCodes() []release.Status_Code {
 	if l.all {

cmd/helm/list_test.go

@@ -118,6 +118,14 @@ func TestListCmd(t *testing.T) {
 			},
 			expected: "thomas-guide\nwild-idea\ncrazy-maps",
 		},
+		{
+			name: "with old releases",
+			resp: []*release.Release{
+				helm.ReleaseMock(&helm.MockReleaseOptions{Name: "thomas-guide"}),
+				helm.ReleaseMock(&helm.MockReleaseOptions{Name: "thomas-guide", StatusCode: release.Status_FAILED}),
+			},
+			expected: "thomas-guide",
+		},
 	}
 
 	var buf bytes.Buffer