From e84ff05a6353ae9e7081aa6d0157195f73d1c313 Mon Sep 17 00:00:00 2001
From: Yusuke KUOKA <ykuoka@gmail.com>
Date: Thu, 23 Aug 2018 09:26:39 +0900
Subject: [PATCH] fix: helmfile should fail on duplicate release name

Fixes #193
---
 state/state.go      | 10 ++++++++++
 state/state_test.go | 23 +++++++++++++++++++++++
 2 files changed, 33 insertions(+)

diff --git a/state/state.go b/state/state.go
index 77861123..bcc1d7cf 100644
--- a/state/state.go
+++ b/state/state.go
@@ -109,6 +109,16 @@ func readFromYaml(content []byte, file string, logger *zap.SugaredLogger) (*Helm
 		state.DeprecatedReleases = []ReleaseSpec{}
 	}
 
+	releaseNameCounts := map[string]int{}
+	for _, r := range state.Releases {
+		releaseNameCounts[r.Name] += 1
+	}
+	for name, c := range releaseNameCounts {
+		if c > 1 {
+			return nil, fmt.Errorf("invalid helmfile: duplicate release name found: there were %d releases named \"%s\"", c, name)
+		}
+	}
+
 	state.logger = logger
 
 	return &state, nil
diff --git a/state/state_test.go b/state/state_test.go
index 63795ee0..4f269307 100644
--- a/state/state_test.go
+++ b/state/state_test.go
@@ -164,6 +164,29 @@ func TestReadFromYaml_FilterNegatives(t *testing.T) {
 	}
 }
 
+// See https://github.com/roboll/helmfile/issues/193
+func TestReadFromYaml_DuplicateReleaseName(t *testing.T) {
+	yamlFile := "example/path/to/yaml/file"
+	yamlContent := []byte(`releases:
+- name: myrelease1
+  chart: mychart1
+  labels:
+    stage: pre
+    foo: bar
+- name: myrelease1
+  chart: mychart2
+  labels:
+    stage: post
+`)
+	_, err := readFromYaml(yamlContent, yamlFile, logger)
+	if err == nil {
+		t.Error("error expected but not happened")
+	}
+	if err.Error() != "invalid helmfile: duplicate release name found: there were 2 releases named \"myrelease1\"" {
+		t.Errorf("unexpected error happened: %v", err)
+	}
+}
+
 func TestLabelParsing(t *testing.T) {
 	cases := []struct {
 		labelString    string