From 3e0f5ea327c9d6d5268d37f231cfd3b355984d99 Mon Sep 17 00:00:00 2001
From: Jeffrey Regan <jregan@google.com>
Date: Thu, 18 Oct 2018 13:09:25 -0700
Subject: [PATCH] Delete penultimate use of Patches field.

---
 pkg/commands/edit/add/addpatch.go             |  2 +-
 pkg/commands/kustfile/kustomizationfile.go    |  7 ++--
 .../kustfile/kustomizationfile_test.go        | 42 +++++++++++++++++++
 pkg/types/kustomization.go                    | 17 ++++----
 4 files changed, 57 insertions(+), 11 deletions(-)

diff --git a/pkg/commands/edit/add/addpatch.go b/pkg/commands/edit/add/addpatch.go
index bb3d5e19e..01af65499 100644
--- a/pkg/commands/edit/add/addpatch.go
+++ b/pkg/commands/edit/add/addpatch.go
@@ -89,7 +89,7 @@ func (o *addPatchOptions) RunAddPatch(fSys fs.FileSystem) error {
 	}
 
 	for _, p := range patches {
-		if patch.Exist(m.PatchesStrategicMerge, p) || kustfile.StringInSlice(p, m.Patches) {
+		if patch.Exist(m.PatchesStrategicMerge, p) {
 			log.Printf("patch %s already in kustomization file", p)
 			continue
 		}
diff --git a/pkg/commands/kustfile/kustomizationfile.go b/pkg/commands/kustfile/kustomizationfile.go
index 4edf743fb..f352c09a6 100644
--- a/pkg/commands/kustfile/kustomizationfile.go
+++ b/pkg/commands/kustfile/kustomizationfile.go
@@ -110,16 +110,17 @@ func (mf *kustomizationFile) Read() (*types.Kustomization, error) {
 	if err != nil {
 		return nil, err
 	}
-	var kustomization types.Kustomization
-	err = yaml.Unmarshal(data, &kustomization)
+	var k types.Kustomization
+	err = yaml.Unmarshal(data, &k)
 	if err != nil {
 		return nil, err
 	}
+	k.DealWithDeprecatedFields()
 	err = mf.parseCommentedFields(data)
 	if err != nil {
 		return nil, err
 	}
-	return &kustomization, err
+	return &k, err
 }
 
 func (mf *kustomizationFile) Write(kustomization *types.Kustomization) error {
diff --git a/pkg/commands/kustfile/kustomizationfile_test.go b/pkg/commands/kustfile/kustomizationfile_test.go
index c192cc4f2..f58dff928 100644
--- a/pkg/commands/kustfile/kustomizationfile_test.go
+++ b/pkg/commands/kustfile/kustomizationfile_test.go
@@ -50,6 +50,48 @@ func TestWriteAndRead(t *testing.T) {
 	}
 }
 
+// Deprecated fields should not survive being read.
+func TestDeprecationOfPatches(t *testing.T) {
+	hasDeprecatedFields := []byte(`
+namePrefix: acme
+patches:
+- alice
+patchesStrategicMerge:
+- bob
+`)
+	fSys := fs.MakeFakeFS()
+	fSys.WriteTestKustomizationWith(hasDeprecatedFields)
+	mf, err := NewKustomizationFile(fSys)
+	if err != nil {
+		t.Fatalf("Unexpected Error: %v", err)
+	}
+	k, err := mf.Read()
+	if err != nil {
+		t.Fatalf("Couldn't read kustomization file: %v\n", err)
+	}
+	if k.NamePrefix != "acme" {
+		t.Fatalf("Unexpected name prefix")
+	}
+	if len(k.Patches) > 0 {
+		t.Fatalf("Expected nothing in Patches.")
+	}
+	if len(k.PatchesStrategicMerge) != 2 {
+		t.Fatalf(
+			"Expected len(k.PatchesStrategicMerge) == 2, got %d",
+			len(k.PatchesStrategicMerge))
+	}
+	m := make(map[string]bool)
+	for _, v := range k.PatchesStrategicMerge {
+		m[string(v)] = true
+	}
+	if _, f := m["alice"]; !f {
+		t.Fatalf("Expected alice in PatchesStrategicMerge")
+	}
+	if _, f := m["bob"]; !f {
+		t.Fatalf("Expected bob in PatchesStrategicMerge")
+	}
+}
+
 func TestNewNotExist(t *testing.T) {
 	fakeFS := fs.MakeFakeFS()
 	_, err := NewKustomizationFile(fakeFS)
diff --git a/pkg/types/kustomization.go b/pkg/types/kustomization.go
index 3e64ee4e1..e5dc648c5 100644
--- a/pkg/types/kustomization.go
+++ b/pkg/types/kustomization.go
@@ -124,13 +124,16 @@ type Kustomization struct {
 // DealWithDeprecatedFields should be called immediately after
 // loading from storage.
 func (k *Kustomization) DealWithDeprecatedFields() {
-	// The Patches field, meant to hold StrategicMerge patches,
-	// is deprecated. Append anything found there to the
-	// PatchesStrategicMerge field.
-	// This happened when the PatchesJson6902 field was introduced.
-	k.PatchesStrategicMerge = patch.Append(
-		k.PatchesStrategicMerge, k.Patches...)
-	k.Patches = []string{}
+	if len(k.Patches) > 0 {
+		// The Patches field, meant to hold strategic merge
+		// patches, is deprecated. Append anything found
+		// there to the PatchesStrategicMerge field.
+		// This happened when the PatchesJson6902 field
+		// was introduced.
+		k.PatchesStrategicMerge = patch.Append(
+			k.PatchesStrategicMerge, k.Patches...)
+		k.Patches = []string{}
+	}
 }
 
 // ConfigMapArgs contains the metadata of how to generate a configmap.