From 853793af8fa80f3f293e0a1a27c5a88c939e18d4 Mon Sep 17 00:00:00 2001
From: Jordan Liggitt <jliggitt@redhat.com>
Date: Mon, 29 Sep 2014 15:06:41 -0400
Subject: [PATCH] Output TOC and tree in sorted order to make output stable
 between invocations. Addresses issue #49

---
 asset.go   |  7 +++++++
 convert.go |  4 ++++
 toc.go     | 15 +++++++++++++--
 3 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/asset.go b/asset.go
index 95b6b94..51771a8 100644
--- a/asset.go
+++ b/asset.go
@@ -10,3 +10,10 @@ type Asset struct {
 	Name string // Key used in TOC -- name by which asset is referenced.
 	Func string // Function name for the procedure returning the asset contents.
 }
+
+// Implement sort.Interface for []Asset based on Path field
+type ByPath []Asset
+
+func (v ByPath) Len() int           { return len(v) }
+func (v ByPath) Swap(i, j int)      { v[i], v[j] = v[j], v[i] }
+func (v ByPath) Less(i, j int) bool { return v[i].Path < v[j].Path }
diff --git a/convert.go b/convert.go
index e0b1a3d..335ca62 100644
--- a/convert.go
+++ b/convert.go
@@ -10,6 +10,7 @@ import (
 	"os"
 	"path/filepath"
 	"regexp"
+	"sort"
 	"strings"
 	"unicode"
 )
@@ -34,6 +35,9 @@ func Translate(c *Config) error {
 		}
 	}
 
+	// Sort to make output stable between invocations
+	sort.Sort(ByPath(toc))
+
 	// Create output file.
 	fd, err := os.Create(c.Output)
 	if err != nil {
diff --git a/toc.go b/toc.go
index 566e6e1..cbbae6e 100644
--- a/toc.go
+++ b/toc.go
@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"sort"
 	"strings"
 )
 
@@ -54,10 +55,20 @@ func (root *assetTree) funcOrNil() string {
 
 func (root *assetTree) writeGoMap(w io.Writer, nident int) {
 	fmt.Fprintf(w, "&_bintree_t{%s, map[string]*_bintree_t{\n", root.funcOrNil())
-	for p, child := range root.Children {
+
+	// Sort to make output stable between invocations
+	filenames := make([]string, len(root.Children))
+	i := 0
+	for filename, _ := range root.Children {
+		filenames[i] = filename
+		i++
+	}
+	sort.Strings(filenames)
+
+	for _, p := range filenames {
 		ident(w, nident+1)
 		fmt.Fprintf(w, `"%s": `, p)
-		child.writeGoMap(w, nident+1)
+		root.Children[p].writeGoMap(w, nident+1)
 	}
 	ident(w, nident)
 	io.WriteString(w, "}}")