WIP: add newlines and indents to self closing tags

encode.go

@@ -51,6 +51,9 @@ func (e *Encoder) Encode(v interface{}) error {
 	}
 
 	enc := newXMLEncoder(e.w)
+
+	// this indent value is for xmlEncoder to track and write booleans. It's a hack
+	enc.indent = e.indent
 	enc.Indent("", e.indent)
 	return enc.generateDocument(pval)
 }

encode_test.go

@@ -115,6 +115,25 @@ var indentRefOmit = `<?xml version="1.0" encoding="UTF-8"?>
 </plist>
 `
 
+var boolRef = `<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0"><dict><key>Absent</key><false/><key>False</key><false/><key>True</key><true/></dict></plist>
+`
+
+var boolIndentRef = `<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+   <dict>
+      <key>Absent</key>
+      <false/>
+      <key>False</key>
+      <false/>
+      <key>True</key>
+      <true/>
+   </dict>
+</plist>
+`
+
 type testStruct struct {
 	UnusedString string `plist:"unused-string"`
 }
@@ -300,28 +319,61 @@ func TestMarshaler(t *testing.T) {
 }
 
 func TestSelfClosing(t *testing.T) {
-	t.Parallel()
+	tests := []struct {
+		description string
+		marshalFunc func(interface{}) ([]byte, error)
+		want        string
+	}{
+		{
+			description: "without indent",
+			marshalFunc: func(in interface{}) ([]byte, error) {
+				return Marshal(in)
+			},
+			want: boolRef,
+		},
+		{
+			description: "indent",
+			marshalFunc: func(in interface{}) ([]byte, error) {
+				return MarshalIndent(in, "   ")
+			},
+			want: boolIndentRef,
+		},
+	}
+
+	type AA struct {
+		AA       bool
+		Multiple []bool
+		Strings  []string
+	}
+	type Foo struct {
+		A  bool
+		B  bool
+		AA AA
+	}
+
 	selfClosing := struct {
 		True   bool
 		False  bool
 		Absent bool
+		Foo    Foo
 	}{
 		True:  true,
 		False: false,
+		Foo:   Foo{AA: AA{Strings: []string{"A", "b"}, Multiple: []bool{false, true, true}}},
 	}
 
-	want := []byte(`<?xml version="1.0" encoding="UTF-8"?>
-<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
-<plist version="1.0"><dict><key>Absent</key><false/><key>False</key><false/><key>True</key><true/></dict></plist>
-`)
-
-	have, err := Marshal(selfClosing)
-	if err != nil {
-		t.Fatal(err)
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.description, func(t *testing.T) {
+			t.Parallel()
+			got, err := tt.marshalFunc(selfClosing)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if string(got) != tt.want {
+				t.Errorf("got\n%s\n, want\n%s\n", got, tt.want)
+			}
+		})
 	}
-
-	if !bytes.Equal(have, want) {
-		t.Errorf("expected \n%s got \n%s\n", have, want)
-	}
-
 }

xml_writer.go

@@ -14,11 +14,14 @@ const xmlDOCTYPE = `<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http:/
 
 type xmlEncoder struct {
 	writer io.Writer
+	indent string
 	*xml.Encoder
+	depth        int
+	writeNewline bool
 }
 
 func newXMLEncoder(w io.Writer) *xmlEncoder {
-	return &xmlEncoder{w, xml.NewEncoder(w)}
+	return &xmlEncoder{writer: w, Encoder: xml.NewEncoder(w)}
 }
 
 func (e *xmlEncoder) generateDocument(pval *plistValue) error {
@@ -60,6 +63,7 @@ func (e *xmlEncoder) generateDocument(pval *plistValue) error {
 }
 
 func (e *xmlEncoder) writePlistValue(pval *plistValue) error {
+	e.depth++
 	switch pval.kind {
 	case String:
 		return e.writeStringValue(pval)
@@ -139,6 +143,11 @@ func (e *xmlEncoder) writeElement(name string, pval *plistValue, valFunc func(*p
 		return err
 	}
 
+	// drop the indent level after array or dictionary tag is closed.
+	if name == "dict" || name == "array" {
+		e.depth--
+	}
+
 	// flush
 	return e.Flush()
 }
@@ -152,6 +161,16 @@ func (e *xmlEncoder) writeArrayValue(pval *plistValue) error {
 				return err
 			}
 		}
+		// if the values of the array are self closing booleans, we have to write a newline + indent
+		// and then decrement depth by 2. 1 for the bool and one for the array key itself.
+		if e.writeNewline {
+			e.writer.Write([]byte("\n"))
+			for i := 0; i < e.depth; i++ {
+				e.writer.Write([]byte(e.indent))
+			}
+			e.depth -= 2
+			e.writeNewline = false
+		}
 		return nil
 	}
 	return e.writeElement("array", pval, tokenFunc)
@@ -211,14 +230,20 @@ func (e *xmlEncoder) writeStringValue(pval *plistValue) error {
 }
 
 func (e *xmlEncoder) writeBoolValue(pval *plistValue) error {
-	// EncodeElement results in <true></true> instead of <true/>
-	// use writer to write self closing tags
-	b := pval.value.(bool)
-	_, err := e.writer.Write([]byte(fmt.Sprintf("<%t/>", b)))
-	if err != nil {
-		return err
+	e.writeNewline = true
+	boolVal := pval.value.(bool)
+	var err error
+	if e.indent != "" {
+		e.writer.Write([]byte("\n"))
+		for i := 0; i < e.depth; i++ {
+			e.writer.Write([]byte(e.indent))
+		}
+		e.depth--
+		_, err = e.writer.Write([]byte(fmt.Sprintf("<%t/>", boolVal)))
+	} else {
+		_, err = e.writer.Write([]byte(fmt.Sprintf("<%t/>", boolVal)))
 	}
-	return nil
+	return err
 }
 
 func (e *xmlEncoder) writeIntegerValue(pval *plistValue) error {