printer: rename methods to make it more readable

printer/nodes.go

@@ -3,7 +3,6 @@ package printer
 import (
 	"bytes"
 	"fmt"
-	"io"
 
 	"github.com/fatih/hcl/ast"
 )
@@ -14,13 +13,14 @@ const (
 	tab     = byte('\t')
 )
 
-func (p *printer) printNode(n ast.Node) []byte {
+// node
+func (p *printer) output(n ast.Node) []byte {
 	var buf bytes.Buffer
 
 	switch t := n.(type) {
 	case *ast.ObjectList:
 		for i, item := range t.Items {
-			buf.Write(p.printObjectItem(item))
+			buf.Write(p.objectItem(item))
 			if i != len(t.Items)-1 {
 				buf.Write([]byte{newline, newline})
 			}
@@ -28,13 +28,13 @@ func (p *printer) printNode(n ast.Node) []byte {
 	case *ast.ObjectKey:
 		buf.WriteString(t.Token.Text)
 	case *ast.ObjectItem:
-		buf.Write(p.printObjectItem(t))
+		buf.Write(p.objectItem(t))
 	case *ast.LiteralType:
 		buf.WriteString(t.Token.Text)
 	case *ast.ListType:
-		buf.Write(p.printList(t))
+		buf.Write(p.list(t))
 	case *ast.ObjectType:
-		buf.Write(p.printObjectType(t))
+		buf.Write(p.objectType(t))
 	default:
 		fmt.Printf(" unknown type: %T\n", n)
 	}
@@ -42,7 +42,7 @@ func (p *printer) printNode(n ast.Node) []byte {
 	return buf.Bytes()
 }
 
-func (p *printer) printObjectItem(o *ast.ObjectItem) []byte {
+func (p *printer) objectItem(o *ast.ObjectItem) []byte {
 	var buf bytes.Buffer
 
 	for i, k := range o.Keys {
@@ -56,21 +56,21 @@ func (p *printer) printObjectItem(o *ast.ObjectItem) []byte {
 		}
 	}
 
-	buf.Write(p.printNode(o.Val))
+	buf.Write(p.output(o.Val))
 	return buf.Bytes()
 }
 
-func (p *printer) printLiteral(l *ast.LiteralType) []byte {
+func (p *printer) literal(l *ast.LiteralType) []byte {
 	return []byte(l.Token.Text)
 }
 
-func (p *printer) printObjectType(o *ast.ObjectType) []byte {
+func (p *printer) objectType(o *ast.ObjectType) []byte {
 	var buf bytes.Buffer
 	buf.WriteString("{")
 	buf.WriteByte(newline)
 
 	for _, item := range o.List.Items {
-		buf.Write(p.indent(p.printObjectItem(item)))
+		buf.Write(p.indent(p.objectItem(item)))
 		buf.WriteByte(newline)
 	}
 
@@ -78,7 +78,8 @@ func (p *printer) printObjectType(o *ast.ObjectType) []byte {
 	return buf.Bytes()
 }
 
-func (p *printer) printList(l *ast.ListType) []byte {
+// printList prints a HCL list
+func (p *printer) list(l *ast.ListType) []byte {
 	var buf bytes.Buffer
 	buf.WriteString("[")
 
@@ -88,8 +89,7 @@ func (p *printer) printList(l *ast.ListType) []byte {
 			buf.WriteByte(newline)
 		}
 
-		buf.WriteByte(tab)
-		buf.Write(p.printNode(item))
+		buf.Write(p.indent(p.output(item)))
 
 		if i != len(l.List)-1 {
 			buf.WriteString(",")
@@ -104,18 +104,15 @@ func (p *printer) printList(l *ast.ListType) []byte {
 	return buf.Bytes()
 }
 
-func writeBlank(buf io.ByteWriter, indent int) {
-	for i := 0; i < indent; i++ {
-		buf.WriteByte(blank)
-	}
-}
-
+// indent indents the lines of the given buffer for each non-empty line
 func (p *printer) indent(buf []byte) []byte {
-	prefix := []byte{tab}
-	if p.cfg.SpaceWidth != 0 {
-		for i := 0; i < p.cfg.SpaceWidth; i++ {
+	var prefix []byte
+	if p.cfg.SpacesWidth != 0 {
+		for i := 0; i < p.cfg.SpacesWidth; i++ {
 			prefix = append(prefix, blank)
 		}
+	} else {
+		prefix = []byte{tab}
 	}
 
 	var res []byte

printer/printer.go

@@ -8,27 +8,20 @@ import (
 )
 
 type printer struct {
-	out  []byte // raw printer result
-	cfg  Config
-	node ast.Node
-}
-
-func (p *printer) output() []byte {
-	return p.printNode(p.node)
+	cfg Config
 }
 
 // A Config node controls the output of Fprint.
 type Config struct {
-	SpaceWidth int // if set, it will use spaces instead of tabs for alignment
+	SpacesWidth int // if set, it will use spaces instead of tabs for alignment
 }
 
-func (c *Config) fprint(output io.Writer, node ast.Node) error {
+func (c *Config) Fprint(output io.Writer, node ast.Node) error {
 	p := &printer{
-		cfg:  *c,
-		node: node,
+		cfg: *c,
 	}
 
-	if _, err := output.Write(p.output()); err != nil {
+	if _, err := output.Write(p.output(node)); err != nil {
 		return err
 	}
 
@@ -41,10 +34,6 @@ func (c *Config) fprint(output io.Writer, node ast.Node) error {
 	return err
 }
 
-func (c *Config) Fprint(output io.Writer, node ast.Node) error {
-	return c.fprint(output, node)
-}
-
 // Fprint "pretty-prints" an HCL node to output
 // It calls Config.Fprint with default settings.
 func Fprint(output io.Writer, node ast.Node) error {

printer/printer_test.go

@@ -113,7 +113,15 @@ func format(src []byte) ([]byte, error) {
 	}
 
 	var buf bytes.Buffer
-	if err := Fprint(&buf, node); err != nil {
+
+	// test with Spaces
+	// cfg := &Config{SpacesWidth: 4}
+	// if err := cfg.Fprint(&buf, node); err != nil {
+	// 	return nil, fmt.Errorf("print: %s", err)
+	// }
+
+	cfg := &Config{}
+	if err := cfg.Fprint(&buf, node); err != nil {
 		return nil, fmt.Errorf("print: %s", err)
 	}