Merge pull request #272 from thockin/master

Add SnippetWriter.Dup(), fix bug in Args.With()

Author: k8s-ci-robot

v2/generator/snippet_writer.go

@@ -123,25 +123,28 @@ func (s *SnippetWriter) Do(format string, args interface{}) *SnippetWriter {
 // SnippetWriter.Do.
 type Args map[interface{}]interface{}
 
-// With makes a copy of a and adds the given key, value pair.
+// With makes a copy of a and adds the given key, value pair. If key overlaps,
+// the new value wins.
 func (a Args) With(key, value interface{}) Args {
-	a2 := Args{key: value}
+	result := Args{}
 	for k, v := range a {
-		a2[k] = v
+		result[k] = v
 	}
-	return a2
+	result[key] = value
+	return result
 }
 
-// WithArgs makes a copy of a and adds the given arguments.
+// WithArgs makes a copy of a and adds the given arguments. If any keys
+// overlap, the values from rhs win.
 func (a Args) WithArgs(rhs Args) Args {
-	a2 := Args{}
-	for k, v := range rhs {
-		a2[k] = v
-	}
+	result := Args{}
 	for k, v := range a {
-		a2[k] = v
+		result[k] = v
+	}
+	for k, v := range rhs {
+		result[k] = v
 	}
-	return a2
+	return result
 }
 
 func (s *SnippetWriter) Out() io.Writer {
@@ -152,3 +155,16 @@ func (s *SnippetWriter) Out() io.Writer {
 func (s *SnippetWriter) Error() error {
 	return s.err
 }
+
+// Dup creates an exact duplicate SnippetWriter with a different io.Writer.
+func (s *SnippetWriter) Dup(w io.Writer) *SnippetWriter {
+	ret := *s
+	ret.w = w
+	return &ret
+}
+
+// Append adds the contents of the io.Reader to this SnippetWriter's buffer.
+func (s *SnippetWriter) Append(r io.Reader) error {
+	_, err := io.Copy(s.w, r)
+	return err
+}

v2/generator/snippet_writer_test.go

@@ -69,3 +69,54 @@ func TestSnippetWriter(t *testing.T) {
 		}
 	}
 }
+
+func TestArgsWith(t *testing.T) {
+	orig := generator.Args{
+		"a": "aaa",
+		"b": "bbb",
+	}
+
+	withC := orig.With("c", "ccc")
+	if len(orig) != 2 {
+		t.Errorf("unexpected change to 'orig': %v", orig)
+	}
+	if len(withC) != 3 {
+		t.Errorf("expected 'withC' to have 3 values: %v", withC)
+	}
+
+	withDE := withC.WithArgs(generator.Args{
+		"d": "ddd",
+		"e": "eee",
+	})
+	if len(orig) != 2 {
+		t.Errorf("unexpected change to 'orig': %v", orig)
+	}
+	if len(withC) != 3 {
+		t.Errorf("unexpected change to 'withC': %v", orig)
+	}
+	if len(withDE) != 5 {
+		t.Errorf("expected 'withDE' to have 5 values: %v", withC)
+	}
+
+	withNewA := orig.With("a", "AAA")
+	if orig["a"] != "aaa" {
+		t.Errorf("unexpected change to 'orig': %v", orig)
+	}
+	if withNewA["a"] != "AAA" {
+		t.Errorf("expected 'withNewA[\"a\"]' to be \"AAA\": %v", withNewA)
+	}
+
+	withNewAB := orig.WithArgs(generator.Args{
+		"a": "AAA",
+		"b": "BBB",
+	})
+	if orig["a"] != "aaa" || orig["b"] != "bbb" {
+		t.Errorf("unexpected change to 'orig': %v", orig)
+	}
+	if withNewAB["a"] != "AAA" {
+		t.Errorf("expected 'withNewAB[\"a\"]' to be \"AAA\": %v", withNewAB)
+	}
+	if withNewAB["b"] != "BBB" {
+		t.Errorf("expected 'withNewAB[\"b\"]' to be \"BBB\": %v", withNewAB)
+	}
+}