Automatically anchor resource selector patterns

docs/fields.md

@@ -283,7 +283,7 @@ patches:
     group: apps
     version: v1
     kind: Deployment
-    name: deploy
+    name: deploy.*
     labelSelector: "env=dev"
     annotationSelector: "zone=west"
 - patch: |-
@@ -295,6 +295,10 @@ patches:
     labelSelector: "env=dev"        
 ```
 
+The `name` and `namespace` fields of the patch target selector are
+automatically anchored regular expressions. This means that the value `myapp`
+is equivalent to `^myapp$`. 
+
 ### patchesStrategicMerge
 
 Each entry in this list should be either a relative

pkg/resmap/resmap.go

@@ -650,11 +650,18 @@ func (m *resWrangler) appendReplaceOrMerge(
 	return nil
 }
 
+func anchorRegex(pattern string) string {
+	if pattern == "" {
+		return pattern
+	}
+	return "^" + pattern + "$"
+}
+
 // Select returns a list of resources that
 // are selected by a Selector
 func (m *resWrangler) Select(s types.Selector) ([]*resource.Resource, error) {
-	ns := regexp.MustCompile(s.Namespace)
-	nm := regexp.MustCompile(s.Name)
+	ns := regexp.MustCompile(anchorRegex(s.Namespace))
+	nm := regexp.MustCompile(anchorRegex(s.Name))
 	var result []*resource.Resource
 	for _, r := range m.Resources() {
 		curId := r.CurId()

pkg/resmap/selector_test.go

@@ -41,6 +41,12 @@ metadata:
     app: name3
   annotations:
     bar: baz
+---
+apiVersion: group1/v1
+kind: Kind2
+metadata:
+  name: x-name1
+  namespace: x-default
 `))
 	if err != nil {
 		t.Fatalf("unexpected error %v", err)
@@ -56,13 +62,13 @@ func TestFindPatchTargets(t *testing.T) {
 	}{
 		{
 			target: types.Selector{
-				Name: "name*",
+				Name: "name.*",
 			},
 			count: 3,
 		},
 		{
 			target: types.Selector{
-				Name:               "name*",
+				Name:               "name.*",
 				AnnotationSelector: "foo=bar",
 			},
 			count: 2,
@@ -78,7 +84,7 @@ func TestFindPatchTargets(t *testing.T) {
 				Gvk: gvk.Gvk{
 					Kind: "Kind1",
 				},
-				Name: "name*",
+				Name: "name.*",
 			},
 			count: 2,
 		},
@@ -92,7 +98,7 @@ func TestFindPatchTargets(t *testing.T) {
 			target: types.Selector{
 				Name: "",
 			},
-			count: 3,
+			count: 4,
 		},
 		{
 			target: types.Selector{
@@ -104,18 +110,60 @@ func TestFindPatchTargets(t *testing.T) {
 			target: types.Selector{
 				Namespace: "",
 			},
-			count: 3,
+			count: 4,
 		},
 		{
 			target: types.Selector{
 				Namespace: "default",
-				Name:      "name*",
+				Name:      "name.*",
 				Gvk: gvk.Gvk{
 					Kind: "Kind1",
 				},
 			},
 			count: 1,
 		},
+		{
+			target: types.Selector{
+				Name: "^name.*",
+			},
+			count: 3,
+		},
+		{
+			target: types.Selector{
+				Name: "name.*$",
+			},
+			count: 3,
+		},
+		{
+			target: types.Selector{
+				Name: "^name.*$",
+			},
+			count: 3,
+		},
+		{
+			target: types.Selector{
+				Namespace: "^def.*",
+			},
+			count: 2,
+		},
+		{
+			target: types.Selector{
+				Namespace: "def.*$",
+			},
+			count: 2,
+		},
+		{
+			target: types.Selector{
+				Namespace: "^def.*$",
+			},
+			count: 2,
+		},
+		{
+			target: types.Selector{
+				Namespace: "default",
+			},
+			count: 2,
+		},
 	}
 	for _, testcase := range testcases {
 		actual, err := rm.Select(testcase.target)