Merge pull request #3506 from natasha41575/FixSmpDirectiveWhenElementNotFound

$patch:delete should not add elements when element is not found

api/builtins/PatchStrategicMergeTransformer.go

@@ -60,11 +60,10 @@ func (p *PatchStrategicMergeTransformerPlugin) Config(
 			"patch appears to be empty; files=%v, Patch=%s", p.Paths, p.Patches)
 	}
 	// Merge the patches, looking for conflicts.
-	m, err := h.ResmapFactory().ConflatePatches(p.loadedPatches)
+	_, err = h.ResmapFactory().ConflatePatches(p.loadedPatches)
 	if err != nil {
 		return err
 	}
-	p.loadedPatches = m.Resources()
 	return nil
 }
 

api/krusty/patchdelete_test.go

@@ -69,28 +69,6 @@ spec:
         image: helloworld
         name: whatever
 `
-	// Allow expected variable to be unused
-	_ = expected
-
-	// Currently, kustomize inserts $patch: delete elements into the resulting resources
-	erroneousActual := `
-apiVersion: apps/v1
-kind: Deployment
-metadata:
-  name: whatever
-spec:
-  template:
-    spec:
-      containers:
-      - env:
-        - $patch: delete
-          name: NOT_EXISTING_FOR_REMOVAL
-        - name: EXISTING
-          value: EXISTING_VALUE
-        image: helloworld
-        name: whatever
-`
-
 	m := th.Run(".", th.MakeDefaultOptions())
-	th.AssertActualEqualsExpected(m, erroneousActual)
+	th.AssertActualEqualsExpected(m, expected)
 }

kyaml/yaml/merge2/merge2.go

@@ -59,6 +59,11 @@ func (m Merger) VisitMap(nodes walk.Sources, s *openapi.ResourceSchema) (*yaml.R
 	}
 	if yaml.IsMissingOrNull(nodes.Dest()) {
 		// Add
+		ps, _ := determineSmpDirective(nodes.Origin())
+		if ps == smpDelete {
+			return walk.ClearNode, nil
+		}
+
 		return nodes.Origin(), nil
 	}
 	if nodes.Origin().IsTaggedNull() {

plugin/builtin/patchstrategicmergetransformer/PatchStrategicMergeTransformer.go

@@ -64,11 +64,10 @@ func (p *plugin) Config(
 			"patch appears to be empty; files=%v, Patch=%s", p.Paths, p.Patches)
 	}
 	// Merge the patches, looking for conflicts.
-	m, err := h.ResmapFactory().ConflatePatches(p.loadedPatches)
+	_, err = h.ResmapFactory().ConflatePatches(p.loadedPatches)
 	if err != nil {
 		return err
 	}
-	p.loadedPatches = m.Resources()
 	return nil
 }