Addressing Comments from Code Review

Addressing comments from code review (https://github.com/kubernetes/kubernetes/pull/55824#pullrequestreview-78597250) in order to simplify the code.

pkg/util/slice/slice.go

@@ -68,3 +68,24 @@ func ContainsString(slice []string, s string, modifier func(s string) string) bo
 	}
 	return false
 }
+
+// RemoveString returns a newly created []string that contains all items from slice that
+// are not equal to s and modifier(s) in case modifier func is provided.
+func RemoveString(slice []string, s string, modifier func(s string) string) []string {
+	newSlice := make([]string, 0)
+	for _, item := range slice {
+		if item == s {
+			continue
+		}
+		if modifier != nil && modifier(item) == s {
+			continue
+		}
+		newSlice = append(newSlice, item)
+	}
+	if len(newSlice) == 0 {
+		// Sanitize for unit tests so we don't need to distinguish empty array
+		// and nil.
+		newSlice = nil
+	}
+	return newSlice
+}

pkg/util/slice/slice_test.go

@@ -106,3 +106,67 @@ func TestContainsString(t *testing.T) {
 		t.Errorf("ContainsString didn't find the string by modifier")
 	}
 }
+
+func TestRemoveString(t *testing.T) {
+	modifier := func(s string) string {
+		if s == "ab" {
+			return "ee"
+		}
+		return s
+	}
+	tests := []struct {
+		testName string
+		input    []string
+		remove   string
+		modifier func(s string) string
+		want     []string
+	}{
+		{
+			testName: "Nil input slice",
+			input:    nil,
+			remove:   "",
+			modifier: nil,
+			want:     nil,
+		},
+		{
+			testName: "Slice doesn't contain the string",
+			input:    []string{"a", "ab", "cdef"},
+			remove:   "NotPresentInSlice",
+			modifier: nil,
+			want:     []string{"a", "ab", "cdef"},
+		},
+		{
+			testName: "All strings removed, result is nil",
+			input:    []string{"a"},
+			remove:   "a",
+			modifier: nil,
+			want:     nil,
+		},
+		{
+			testName: "No modifier func, one string removed",
+			input:    []string{"a", "ab", "cdef"},
+			remove:   "ab",
+			modifier: nil,
+			want:     []string{"a", "cdef"},
+		},
+		{
+			testName: "No modifier func, all(three) strings removed",
+			input:    []string{"ab", "a", "ab", "cdef", "ab"},
+			remove:   "ab",
+			modifier: nil,
+			want:     []string{"a", "cdef"},
+		},
+		{
+			testName: "Removed both the string and the modifier func result",
+			input:    []string{"a", "cd", "ab", "ee"},
+			remove:   "ee",
+			modifier: modifier,
+			want:     []string{"a", "cd"},
+		},
+	}
+	for _, tt := range tests {
+		if got := RemoveString(tt.input, tt.remove, tt.modifier); !reflect.DeepEqual(got, tt.want) {
+			t.Errorf("%v: RemoveString(%v, %q, %T) = %v WANT %v", tt.testName, tt.input, tt.remove, tt.modifier, got, tt.want)
+		}
+	}
+}