Variable expansion bug.

README.md

@@ -52,6 +52,9 @@ improvements.
 
   1. A clean, modern implementation in Go, that doesn't depend on the whole Plan
      9 stack.
+  1. Parallel by default. Modern computers can build more than one C file at a
+     time. Cases that should not be run in parallel are the exception. Use
+     `-p=1` if this is the case.
   1. Use Go regular expressions, which are perl-like. The original mk used plan9
      regex, which few people know or care to learn.
   1. Allow blank lines in recipes. A recipe is any indented block of text, and
@@ -60,8 +63,6 @@ improvements.
   1. Add an 'S' attribute to execute recipes with programs other than sh. This
      way, you don't have to separate your six line python script into its own
      file. Just stick it directly in the mkfile.
-  1. Use sh syntax for command insertion (i.e. backticks) rather than rc shell
-     syntax.
   1. Pretty colors.
 
 # Current State

TODO.md

@@ -0,0 +1,20 @@
+
+# Short-term
+    * Unit tests.
+    * Expanding regex matches in targets.
+    * Dummy rule for multiple explicit targets
+    * Expand `$newprereq`.
+    * Expand `$alltargets`.
+    * Man page.
+    * Namelist syntax.
+    * Environment variables.
+
+# Long-term
+    * Nicer syntax for alternative-shell rules.
+    * An attribute to demand n processors for a particular rule. This way
+      resource hog rules can be run on their own without disabling parallel
+      make.
+    * A switch that prints the rules that will be executed and prompts to user
+      to do so. I often find myself doing `mk -n` before `mk` to make sure my
+      rules aren't bogus.
+

expand.go

@@ -13,12 +13,13 @@ func expand(input string, vars map[string][]string, expandBackticks bool) []stri
 	expanded := ""
 	var i, j int
 	for i = 0; i < len(input); {
-		j = i + strings.IndexAny(input[i:], "\"'`$\\")
+		j = strings.IndexAny(input[i:], "\"'`$\\")
 
 		if j < 0 {
 			expanded += input[i:]
 			break
 		}
+		j += i
 
 		expanded += input[i:j]
 		c, w := utf8.DecodeRuneInString(input[j:])

graph.go

@@ -56,7 +56,6 @@ type node struct {
 	flags     nodeFlag          // bitwise combination of node flags
 }
 
-
 // Update a node's timestamp and 'exists' flag.
 func (u *node) updateTimestamp() {
 	info, err := os.Stat(u.name)
@@ -283,7 +282,7 @@ func (g *graph) vacuous(u *node) bool {
 
 // Check for cycles
 func (g *graph) cyclecheck(u *node) {
-    if u.flags & nodeFlagCycle != 0 && len(u.prereqs) > 0 {
+	if u.flags&nodeFlagCycle != 0 && len(u.prereqs) > 0 {
 		mkError(fmt.Sprintf("cycle in the graph detected at target %s", u.name))
 	}
 	u.flags |= nodeFlagCycle

lex.go

@@ -1,10 +1,9 @@
-
 package main
 
 import (
+	"fmt"
 	"strings"
 	"unicode/utf8"
-    "fmt"
 )
 
 type tokenType int

parse.go

@@ -5,10 +5,10 @@ package main
 
 import (
 	"fmt"
-	"regexp"
-	"strings"
 	"io/ioutil"
 	"os"
+	"regexp"
+	"strings"
 )
 
 type parser struct {

recipe.go

@@ -152,7 +152,7 @@ func subprocess(program string,
 		var outbytes []byte
 		outbytes, err = cmd.Output()
 		output = string(outbytes)
-		if output[len(output)-1] == '\n' {
+		if len(output) > 0 && output[len(output)-1] == '\n' {
 			output = output[:len(output)-1]
 		}
 	} else {