added colorful printing

README.md

@@ -26,13 +26,13 @@ By default, `pup` will fill in missing tags, and properly indent the page.
 
 ```bash
 $ cat robots.html
-# nasty looking html
-$ cat robots.html | pup
-# cleaned and indented html
+# nasty looking HTML
+$ cat robots.html | pup --color
+# cleaned, indented, and colorful HTML
 ```
 
 ###Filter by tag
-```
+```bash
 $ pup < robots.html title
 <title>
  Robots exclusion standard - Wikipedia, the free encyclopedia
@@ -40,7 +40,7 @@ $ pup < robots.html title
 ```
 
 ###Filter by id
-```
+```bash
 $ pup < robots.html span#See_also
 <span class="mw-headline" id="See_also">
  See also
@@ -49,19 +49,20 @@ $ pup < robots.html span#See_also
 
 ###Chain selectors together
 
-The following two commands are equivalent.
+The following two commands are equivalent. (NOTE: pipes do not work with the
+`--color` flag)
 
-```
+```bash
 $ pup < robots.html table.navbox ul a | tail
 ```
 
-```
+```bash
 $ pup < robots.html table.navbox | pup ul | pup a | tail
 ```
 
 Both produce the ouput:
 
-```
+```bash
 </a>
 <a href="/wiki/Stop_words" title="Stop words">
  Stop words
@@ -75,13 +76,15 @@ Both produce the ouput:
 ```
 
 ###How many nodes are selected by a filter?
-```
+
+```bash
 $ pup < robots.html a -n
 283
 ```
 
 ###Limit print level
-```
+
+```bash
 $ pup < robots.html table -l 2
 <table class="metadata plainlinks ambox ambox-content" role="presentation">
  <tbody>
@@ -105,4 +108,3 @@ $ pup < robots.html table -l 2
 * Attribute css selectors.
 * Print attribute value rather than html ({href}) 
 * Print result as JSON (--json)
-* Print colorfully

main.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"code.google.com/p/go.net/html"
-	"code.google.com/p/go.net/html/atom"
 	"fmt"
 	"github.com/ericchiang/pup/selector"
 	"io"
@@ -12,12 +11,15 @@ import (
 	"strings"
 )
 
+const VERSION = "0.1.0"
+
 var (
 	// Flags
 	inputStream   io.ReadCloser = os.Stdin
-	sep           string        = " "
+	indentString  string        = " "
 	maxPrintLevel int           = -1
 	printNumber   bool          = false
+	printColor    bool          = false
 
 	// Helpers
 	whitespaceRegexp *regexp.Regexp = regexp.MustCompile(`^\s*$`)
@@ -25,67 +27,6 @@ var (
 	postWhitespace   *regexp.Regexp = regexp.MustCompile(`\s+$`)
 )
 
-func printIndent(level int) {
-	for ; level > 0; level-- {
-		fmt.Print(sep)
-	}
-}
-
-// Is this node a tag with no end tag such as <meta> or <br>?
-// http://www.w3.org/TR/html-markup/syntax.html#syntax-elements
-func isVoidElement(n *html.Node) bool {
-	switch n.DataAtom {
-	case atom.Area, atom.Base, atom.Br, atom.Col, atom.Command, atom.Embed,
-		atom.Hr, atom.Img, atom.Input, atom.Keygen, atom.Link,
-		atom.Meta, atom.Param, atom.Source, atom.Track, atom.Wbr:
-		return true
-	}
-	return false
-
-}
-
-func printChildren(n *html.Node, level int) {
-	if maxPrintLevel > -1 {
-		if level >= maxPrintLevel {
-			printIndent(level)
-			fmt.Println("...")
-			return
-		}
-	}
-	child := n.FirstChild
-	for child != nil {
-		PrintNode(child, level)
-		child = child.NextSibling
-	}
-}
-
-func PrintNode(n *html.Node, level int) {
-	switch n.Type {
-	case html.TextNode:
-		s := n.Data
-		if !whitespaceRegexp.MatchString(s) {
-			s = preWhitespace.ReplaceAllString(s, "")
-			s = postWhitespace.ReplaceAllString(s, "")
-			printIndent(level)
-			fmt.Println(s)
-		}
-	case html.ElementNode:
-		printIndent(level)
-		fmt.Printf("<%s", n.Data)
-		for _, a := range n.Attr {
-			fmt.Printf(` %s="%s"`, a.Key, a.Val)
-		}
-		fmt.Print(">\n")
-		if !isVoidElement(n) {
-			printChildren(n, level+1)
-			printIndent(level)
-			fmt.Printf("</%s>\n", n.Data)
-		}
-	case html.CommentNode, html.DoctypeNode, html.DocumentNode:
-		printChildren(n, level)
-	}
-}
-
 func Fatal(format string, args ...interface{}) {
 	fmt.Fprintf(os.Stderr, format, args...)
 	fmt.Fprintf(os.Stderr, "\n")
@@ -93,18 +34,24 @@ func Fatal(format string, args ...interface{}) {
 }
 
 func printHelp() {
-	Fatal(`Usage:
+	helpString := `Usage
 
     pup [list of css selectors]
 
-Flags:
+Version
 
+    %s
+
+Flags
+
+    -c --color         print result with color
     -f --file          file to read from
     -h --help          display this help
     -i --indent        number of spaces to use for indent or character
     -n --number        print number of elements selected
-    -l --level         restrict number of levels printed 
-`)
+    -l --limit         restrict number of levels printed
+    --version          display version`
+	Fatal(helpString, VERSION)
 }
 
 func processFlags(cmds []string) []string {
@@ -120,6 +67,8 @@ func processFlags(cmds []string) []string {
 	for i = 0; i < len(cmds); i++ {
 		cmd := cmds[i]
 		switch cmd {
+		case "-c", "--color":
+			printColor = true
 		case "-f", "--file":
 			filename := cmds[i+1]
 			inputStream, err = os.Open(filename)
@@ -133,20 +82,22 @@ func processFlags(cmds []string) []string {
 		case "-i", "--indent":
 			indentLevel, err := strconv.Atoi(cmds[i+1])
 			if err == nil {
-				sep = strings.Repeat(" ", indentLevel)
+				indentString = strings.Repeat(" ", indentLevel)
 			} else {
-				sep = cmds[i+1]
+				indentString = cmds[i+1]
 			}
 			i++
 		case "-n", "--number":
 			printNumber = true
-		case "-l", "--level":
+		case "-l", "--limit":
 			maxPrintLevel, err = strconv.Atoi(cmds[i+1])
 			if err != nil {
 				Fatal("Argument for '%s' must be numeric",
 					cmds)
 			}
 			i++
+		case "--version":
+			Fatal(VERSION)
 		default:
 			if cmd[0] == '-' {
 				Fatal("Unrecognized flag '%s'", cmd)
@@ -191,6 +142,7 @@ func main() {
 		fmt.Println(len(currNodes))
 	} else {
 		for _, s := range currNodes {
+			// defined in `printing.go`
 			PrintNode(s, 0)
 		}
 	}

printing.go

@@ -0,0 +1,98 @@
+package main
+
+import (
+	"code.google.com/p/go.net/html"
+	"code.google.com/p/go.net/html/atom"
+	"fmt"
+	"github.com/fatih/color"
+)
+
+var (
+	tagColor     *color.Color = color.New(color.FgYellow).Add(color.Bold)
+	tokenColor                = color.New(color.FgCyan).Add(color.Bold)
+	attrKeyColor              = color.New(color.FgRed)
+	quoteColor                = color.New(color.FgBlue)
+)
+
+func printIndent(level int) {
+	for ; level > 0; level-- {
+		fmt.Print(indentString)
+	}
+}
+
+// Is this node a tag with no end tag such as <meta> or <br>?
+// http://www.w3.org/TR/html-markup/syntax.html#syntax-elements
+func isVoidElement(n *html.Node) bool {
+	switch n.DataAtom {
+	case atom.Area, atom.Base, atom.Br, atom.Col, atom.Command, atom.Embed,
+		atom.Hr, atom.Img, atom.Input, atom.Keygen, atom.Link,
+		atom.Meta, atom.Param, atom.Source, atom.Track, atom.Wbr:
+		return true
+	}
+	return false
+
+}
+
+func printChildren(n *html.Node, level int) {
+	if maxPrintLevel > -1 {
+		if level >= maxPrintLevel {
+			printIndent(level)
+			fmt.Println("...")
+			return
+		}
+	}
+	child := n.FirstChild
+	for child != nil {
+		PrintNode(child, level)
+		child = child.NextSibling
+	}
+}
+
+func PrintNode(n *html.Node, level int) {
+	switch n.Type {
+	case html.TextNode:
+		s := n.Data
+		if !whitespaceRegexp.MatchString(s) {
+			s = preWhitespace.ReplaceAllString(s, "")
+			s = postWhitespace.ReplaceAllString(s, "")
+			printIndent(level)
+			fmt.Println(s)
+		}
+	case html.ElementNode:
+		printIndent(level)
+		if printColor {
+			tokenColor.Print("<")
+			tagColor.Printf("%s", n.Data)
+		} else {
+			fmt.Printf("<%s", n.Data)
+		}
+		for _, a := range n.Attr {
+			if printColor {
+				fmt.Print(" ")
+				attrKeyColor.Printf("%s", a.Key)
+				tokenColor.Print("=")
+				quoteColor.Printf(`"%s"`, a.Val)
+			} else {
+				fmt.Printf(` %s="%s"`, a.Key, a.Val)
+			}
+		}
+		if printColor {
+			tokenColor.Println(">")
+		} else {
+			fmt.Print(">\n")
+		}
+		if !isVoidElement(n) {
+			printChildren(n, level+1)
+			printIndent(level)
+			if printColor {
+				tokenColor.Print("</")
+				tagColor.Printf("%s", n.Data)
+				tokenColor.Println(">")
+			} else {
+				fmt.Printf("</%s>\n", n.Data)
+			}
+		}
+	case html.CommentNode, html.DoctypeNode, html.DocumentNode:
+		printChildren(n, level)
+	}
+}