Use OpenAPI when merging (3way) resources

- When merging (3way) resources use the patch strategy from the openAPI if the definition exists for the field
- Allow disabling of guessing patch strategy merge keys when no definition exists
- Support defining strategy and key directly on configuration fields through line and header coments
- Support attaching schema to parent fields of lists, and propagating -- e.g. that a field is a PodTemplate

kyaml/yaml/merge3/merge3_test.go

@@ -15,24 +15,27 @@ var testCases = [][]testCase{scalarTestCases, listTestCases, mapTestCases, eleme
 
 func TestMerge(t *testing.T) {
 	for i := range testCases {
-		for _, tc := range testCases[i] {
-			actual, err := MergeStrings(tc.local, tc.origin, tc.update)
-			if tc.err == nil {
-				if !assert.NoError(t, err, tc.description) {
-					t.FailNow()
+		for j := range testCases[i] {
+			tc := testCases[i][j]
+			t.Run(tc.description, func(t *testing.T) {
+				actual, err := MergeStrings(tc.local, tc.origin, tc.update, !tc.noInfer)
+				if tc.err == nil {
+					if !assert.NoError(t, err, tc.description) {
+						t.FailNow()
+					}
+					if !assert.Equal(t,
+						strings.TrimSpace(tc.expected), strings.TrimSpace(actual), tc.description) {
+						t.FailNow()
+					}
+				} else {
+					if !assert.Errorf(t, err, tc.description) {
+						t.FailNow()
+					}
+					if !assert.Contains(t, tc.err.Error(), err.Error()) {
+						t.FailNow()
+					}
 				}
-				if !assert.Equal(t,
-					strings.TrimSpace(tc.expected), strings.TrimSpace(actual), tc.description) {
-					t.FailNow()
-				}
-			} else {
-				if !assert.Errorf(t, err, tc.description) {
-					t.FailNow()
-				}
-				if !assert.Contains(t, tc.err.Error(), err.Error()) {
-					t.FailNow()
-				}
-			}
+			})
 		}
 	}
 }
@@ -44,4 +47,5 @@ type testCase struct {
 	local       string
 	expected    string
 	err         error
+	noInfer     bool
 }