Prettier printing.

expand.go

@@ -196,14 +196,14 @@ func expandSigils(input string, vars map[string][]string) []string {
 func expandRecipeSigils(input string, vars map[string][]string) string {
 	expanded := ""
 	for i := 0; i < len(input); {
-		j := strings.IndexAny(input[i:], "$\\")
-		if j < 0 {
+		off := strings.IndexAny(input[i:], "$\\")
+		if off < 0 {
 			expanded += input[i:]
 			break
 		}
+		expanded += input[i : i+off]
+		i += off
 
-		expanded += input[i:j]
-		i = j
 		c, w := utf8.DecodeRuneInString(input[i:])
 		if c == '$' {
 			i += w

lex.go

@@ -49,6 +49,7 @@ type token struct {
 	typ  tokenType // token type
 	val  string    // token string
 	line int       // line where it was found
+	col  int       // column on which the token began
 }
 
 func (t *token) String() string {
@@ -65,6 +66,7 @@ type lexer struct {
 	input    string     // input string to be lexed
 	output   chan token // channel on which tokens are sent
 	start    int        // token beginning
+	startcol int        // column on which the token begins
 	pos      int        // position within input
 	line     int        // line within input
 	col      int        // column within input
@@ -129,11 +131,13 @@ func (l *lexer) next() rune {
 func (l *lexer) skip() {
 	l.next()
 	l.start = l.pos
+	l.startcol = l.col
 }
 
 func (l *lexer) emit(typ tokenType) {
-	l.output <- token{typ, l.input[l.start:l.pos], l.line}
+	l.output <- token{typ, l.input[l.start:l.pos], l.line, l.startcol}
 	l.start = l.pos
+	l.startcol = 0
 }
 
 // Consume the next run if it is in the given string.
@@ -189,7 +193,7 @@ func (l *lexer) skipUntil(invalid string) {
 
 // Start a new lexer to lex the given input.
 func lex(input string) (*lexer, chan token) {
-	l := &lexer{input: input, output: make(chan token), line: 1, indented: true}
+	l := &lexer{input: input, output: make(chan token), line: 1, col: 0, indented: true}
 	go l.run()
 	return l, l.output
 }

mk.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"io/ioutil"
 	"os"
+	"sync"
 )
 
 // True if messages should be printed without fancy colors.
@@ -13,6 +14,9 @@ var nocolor bool = false
 // True if we are no actualyl executing any recipes or updating any timestamps.
 var dryrun bool = false
 
+// Lock on standard out, messages don't get interleaved too much.
+var mkMsgMutex sync.Mutex
+
 // The maximum number of times an rule may be applied.
 const max_rule_cnt = 3
 
@@ -29,7 +33,9 @@ const (
 
 func mk(rs *ruleSet, target string, dryrun bool) {
 	g := buildgraph(rs, target)
-	//g.visualize(os.Stdout)
+	if g.root.exists {
+		return
+	}
 	mkNode(g, g.root)
 }
 
@@ -129,13 +135,13 @@ func mkNode(g *graph, u *node) {
 
 	// execute the recipe, unless the prereqs failed
 	if finalstatus != nodeStatusFailed {
-		mkPrintMessage("mking " + u.name)
+		//mkPrintMessage("mking " + u.name)
 		if !dorecipe(u.name, u, e) {
 			finalstatus = nodeStatusFailed
 		}
 	}
 
-	mkPrintSuccess("finished mking " + u.name)
+	//mkPrintSuccess("finished mking " + u.name)
 }
 
 func mkError(msg string) {
@@ -158,26 +164,34 @@ func mkPrintSuccess(msg string) {
 }
 
 func mkPrintMessage(msg string) {
+	mkMsgMutex.Lock()
 	if nocolor {
 		fmt.Println(msg)
 	} else {
 		fmt.Printf("%s%s%s\n", colorBlue, msg, colorDefault)
 	}
+	mkMsgMutex.Unlock()
 }
 
-func mkPrintRecipe(msg string) {
-	if !nocolor {
-		os.Stdout.WriteString(colorYellow)
+func mkPrintRecipe(target string, recipe string) {
+	mkMsgMutex.Lock()
+	if nocolor {
+		fmt.Printf("%s: ", target)
+	} else {
+		fmt.Printf("%s%s%s => %s", colorBlue, target, colorDefault, colorMagenta)
+	}
+	printIndented(os.Stdout, recipe, len(target)+4)
+	if len(recipe) == 0 {
+		os.Stdout.WriteString("\n")
 	}
-	printIndented(os.Stdout, msg)
 	if !nocolor {
 		os.Stdout.WriteString(colorDefault)
 	}
+	mkMsgMutex.Unlock()
 }
 
 func main() {
 	var mkfilepath string
-	var dryrun bool
 	flag.StringVar(&mkfilepath, "f", "mkfile", "use the given file as mkfile")
 	flag.BoolVar(&dryrun, "n", false, "print commands without actually executing")
 	flag.Parse()

parse.go

@@ -76,7 +76,7 @@ func parseInto(input string, name string, rules *ruleSet) {
 
 	// insert a dummy newline to allow parsing of any assignments or recipeless
 	// rules to finish.
-	state = state(p, token{tokenNewline, "\n", l.line})
+	state = state(p, token{tokenNewline, "\n", l.line, l.col})
 
 	// TODO: Error when state != parseTopLevel
 }
@@ -339,7 +339,7 @@ func parseRecipe(p *parser, t token) parserStateFun {
 	}
 
 	if t.typ == tokenRecipe {
-		r.recipe = t.val
+		r.recipe = stripIndentation(t.val, t.col)
 	}
 
 	p.rules.add(r)

recipe.go

@@ -10,28 +10,57 @@ import (
 	"os"
 	"os/exec"
 	"strings"
+	"unicode/utf8"
 )
 
 // Try to unindent a recipe, so that it begins an column 0. (This is mainly for
 // recipes in python, or other indentation-significant languages.)
-//func stripIndentation(s string) string {
-
-//}
-
-// Indent each line of a recipe.
-func printIndented(out io.Writer, s string) {
+func stripIndentation(s string, mincol int) string {
+	// trim leading whitespace
 	reader := bufio.NewReader(strings.NewReader(s))
+	output := ""
 	for {
 		line, err := reader.ReadString('\n')
-		if len(line) > 0 {
-			io.WriteString(out, "    ")
-			io.WriteString(out, line)
+		col := 0
+		i := 0
+		for i < len(line) && col < mincol {
+			c, w := utf8.DecodeRuneInString(line[i:])
+			if strings.IndexRune(" \t\n", c) >= 0 {
+				col += 1
+				i += w
+			} else {
+				break
+			}
 		}
 
+		output += line[i:]
+
 		if err != nil {
 			break
 		}
 	}
+
+	return output
+}
+
+// Indent each line of a recipe.
+func printIndented(out io.Writer, s string, ind int) {
+	indentation := strings.Repeat(" ", ind)
+	reader := bufio.NewReader(strings.NewReader(s))
+	firstline := true
+	for {
+		line, err := reader.ReadString('\n')
+		if len(line) > 0 {
+			if !firstline {
+				io.WriteString(out, indentation)
+			}
+			io.WriteString(out, line)
+		}
+		if err != nil {
+			break
+		}
+		firstline = false
+	}
 }
 
 // Execute a recipe.
@@ -70,7 +99,7 @@ func dorecipe(target string, u *node, e *edge) bool {
 	}
 
 	if !e.r.attributes.quiet {
-		mkPrintRecipe(input)
+		mkPrintRecipe(target, input)
 	}
 
 	if dryrun {