From d26144be298deeec4474796759073d743faf3bb4 Mon Sep 17 00:00:00 2001
From: David Symonds <dsymonds@golang.org>
Date: Fri, 4 Nov 2011 08:34:37 +1100
Subject: [PATCH] gofix: make fix order implicit by date.

This partially undoes 8fd7e6d070c8, but preserves its semantics.
More importantly, it results in the data about each fix being
decentralised, which makes it easier for new fixes to be added,
and other gofix users to slot new fixes in.

It also adds some useful metadata that could be used in the future.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5306092
---
 src/cmd/gofix/error.go         |  3 +-
 src/cmd/gofix/filepath.go      |  5 ++++
 src/cmd/gofix/fix.go           | 54 ++++++++++++----------------------
 src/cmd/gofix/httpfinalurl.go  |  5 ++++
 src/cmd/gofix/httpfs.go        |  5 ++++
 src/cmd/gofix/httpheaders.go   |  5 ++++
 src/cmd/gofix/httpserver.go    |  5 ++++
 src/cmd/gofix/imagecolor.go    |  5 ++++
 src/cmd/gofix/imagenew.go      |  5 ++++
 src/cmd/gofix/iocopyn.go       |  5 ++++
 src/cmd/gofix/main.go          |  4 ++-
 src/cmd/gofix/mapdelete.go     |  5 ++++
 src/cmd/gofix/math.go          |  5 ++++
 src/cmd/gofix/netdial.go       |  9 ++++++
 src/cmd/gofix/netudpgroup.go   |  5 ++++
 src/cmd/gofix/oserrorstring.go |  5 ++++
 src/cmd/gofix/osopen.go        |  5 ++++
 src/cmd/gofix/procattr.go      |  5 ++++
 src/cmd/gofix/reflect.go       |  5 ++++
 src/cmd/gofix/signal.go        |  5 ++++
 src/cmd/gofix/sorthelpers.go   |  5 ++++
 src/cmd/gofix/sortslice.go     |  5 ++++
 src/cmd/gofix/stringssplit.go  |  5 ++++
 src/cmd/gofix/url.go           |  5 ++++
 24 files changed, 133 insertions(+), 37 deletions(-)

diff --git a/src/cmd/gofix/error.go b/src/cmd/gofix/error.go
index e0ced633d9..5e20ff683b 100644
--- a/src/cmd/gofix/error.go
+++ b/src/cmd/gofix/error.go
@@ -11,11 +11,12 @@ import (
 )
 
 func init() {
-	fixes = append(fixes, errorFix)
+	register(errorFix)
 }
 
 var errorFix = fix{
 	"error",
+	"2011-11-02",
 	errorFn,
 	`Use error instead of os.Error.
 
diff --git a/src/cmd/gofix/filepath.go b/src/cmd/gofix/filepath.go
index 3edccabfa6..f31226018a 100644
--- a/src/cmd/gofix/filepath.go
+++ b/src/cmd/gofix/filepath.go
@@ -8,8 +8,13 @@ import (
 	"go/ast"
 )
 
+func init() {
+	register(filepathFix)
+}
+
 var filepathFix = fix{
 	"filepath",
+	"2011-06-26",
 	filepathFunc,
 	`Adapt code from filepath.[List]SeparatorString to string(filepath.[List]Separator).
 
diff --git a/src/cmd/gofix/fix.go b/src/cmd/gofix/fix.go
index f7b55b073d..394685a15a 100644
--- a/src/cmd/gofix/fix.go
+++ b/src/cmd/gofix/fix.go
@@ -24,45 +24,29 @@ import (
 
 type fix struct {
 	name string
+	date string // date that fix was introduced, in YYYY-MM-DD format
 	f    func(*ast.File) bool
 	desc string
 }
 
-// main runs sort.Sort(fixes) before printing list of fixes.
-type fixlist []fix
-
-func (f fixlist) Len() int           { return len(f) }
-func (f fixlist) Swap(i, j int)      { f[i], f[j] = f[j], f[i] }
-func (f fixlist) Less(i, j int) bool { return f[i].name < f[j].name }
-
-var fixes = fixlist{
-	// NOTE: This list must be in chronological order,
-	// so that code using APIs that changed multiple times
-	// can be updated in the correct order.
-	// Add new fixes to bottom of list.  Do not sort.
-	httpserverFix,
-	procattrFix,
-	netdialFix,
-	netlookupFix,
-	tlsdialFix,
-	osopenFix,
-	reflectFix,
-	httpFinalURLFix,
-	httpHeadersFix,
-	oserrorstringFix,
-	sortsliceFix,
-	filepathFix,
-	httpFileSystemFix,
-	stringssplitFix,
-	signalFix,
-	sorthelpersFix,
-	urlFix,
-	netudpgroupFix,
-	imagenewFix,
-	mathFix,
-	ioCopyNFix,
-	imagecolorFix,
-	mapdeleteFix,
+// main runs sort.Sort(byName(fixes)) before printing list of fixes.
+type byName []fix
+
+func (f byName) Len() int           { return len(f) }
+func (f byName) Swap(i, j int)      { f[i], f[j] = f[j], f[i] }
+func (f byName) Less(i, j int) bool { return f[i].name < f[j].name }
+
+// main runs sort.Sort(byDate(fixes)) before applying fixes.
+type byDate []fix
+
+func (f byDate) Len() int           { return len(f) }
+func (f byDate) Swap(i, j int)      { f[i], f[j] = f[j], f[i] }
+func (f byDate) Less(i, j int) bool { return f[i].date < f[j].date }
+
+var fixes []fix
+
+func register(f fix) {
+	fixes = append(fixes, f)
 }
 
 // walk traverses the AST x, calling visit(y) for each node y in the tree but
diff --git a/src/cmd/gofix/httpfinalurl.go b/src/cmd/gofix/httpfinalurl.go
index 6051a2f3f9..49b9f1c516 100644
--- a/src/cmd/gofix/httpfinalurl.go
+++ b/src/cmd/gofix/httpfinalurl.go
@@ -8,8 +8,13 @@ import (
 	"go/ast"
 )
 
+func init() {
+	register(httpFinalURLFix)
+}
+
 var httpFinalURLFix = fix{
 	"httpfinalurl",
+	"2011-05-13",
 	httpfinalurl,
 	`Adapt http Get calls to not have a finalURL result parameter.
 
diff --git a/src/cmd/gofix/httpfs.go b/src/cmd/gofix/httpfs.go
index 317330619e..625dd0f7db 100644
--- a/src/cmd/gofix/httpfs.go
+++ b/src/cmd/gofix/httpfs.go
@@ -9,8 +9,13 @@ import (
 	"go/token"
 )
 
+func init() {
+	register(httpFileSystemFix)
+}
+
 var httpFileSystemFix = fix{
 	"httpfs",
+	"2011-06-27",
 	httpfs,
 	`Adapt http FileServer to take a FileSystem.
 
diff --git a/src/cmd/gofix/httpheaders.go b/src/cmd/gofix/httpheaders.go
index e9856f5db4..0bce12b512 100644
--- a/src/cmd/gofix/httpheaders.go
+++ b/src/cmd/gofix/httpheaders.go
@@ -8,8 +8,13 @@ import (
 	"go/ast"
 )
 
+func init() {
+	register(httpHeadersFix)
+}
+
 var httpHeadersFix = fix{
 	"httpheaders",
+	"2011-06-16",
 	httpheaders,
 	`Rename http Referer, UserAgent, Cookie, SetCookie, which are now methods.
 
diff --git a/src/cmd/gofix/httpserver.go b/src/cmd/gofix/httpserver.go
index cf8d16a978..7aa6517864 100644
--- a/src/cmd/gofix/httpserver.go
+++ b/src/cmd/gofix/httpserver.go
@@ -9,8 +9,13 @@ import (
 	"go/token"
 )
 
+func init() {
+	register(httpserverFix)
+}
+
 var httpserverFix = fix{
 	"httpserver",
+	"2011-03-15",
 	httpserver,
 	`Adapt http server methods and functions to changes
 made to the http ResponseWriter interface.
diff --git a/src/cmd/gofix/imagecolor.go b/src/cmd/gofix/imagecolor.go
index c7900e4657..1aac40a6fd 100644
--- a/src/cmd/gofix/imagecolor.go
+++ b/src/cmd/gofix/imagecolor.go
@@ -8,8 +8,13 @@ import (
 	"go/ast"
 )
 
+func init() {
+	register(imagecolorFix)
+}
+
 var imagecolorFix = fix{
 	"imagecolor",
+	"2011-10-04",
 	imagecolor,
 	`Adapt code to types moved from image to color.
 
diff --git a/src/cmd/gofix/imagenew.go b/src/cmd/gofix/imagenew.go
index 07cbef5697..b4e36d4f0c 100644
--- a/src/cmd/gofix/imagenew.go
+++ b/src/cmd/gofix/imagenew.go
@@ -8,8 +8,13 @@ import (
 	"go/ast"
 )
 
+func init() {
+	register(imagenewFix)
+}
+
 var imagenewFix = fix{
 	"imagenew",
+	"2011-09-14",
 	imagenew,
 	`Adapt image.NewXxx calls to pass an image.Rectangle instead of (w, h int).
 
diff --git a/src/cmd/gofix/iocopyn.go b/src/cmd/gofix/iocopyn.go
index f911dd7403..720f3c6890 100644
--- a/src/cmd/gofix/iocopyn.go
+++ b/src/cmd/gofix/iocopyn.go
@@ -8,8 +8,13 @@ import (
 	"go/ast"
 )
 
+func init() {
+	register(ioCopyNFix)
+}
+
 var ioCopyNFix = fix{
 	"iocopyn",
+	"2011-09-30",
 	ioCopyN,
 	`Rename io.Copyn to io.CopyN.
 
diff --git a/src/cmd/gofix/main.go b/src/cmd/gofix/main.go
index 1d0f4b0f07..fbb705c076 100644
--- a/src/cmd/gofix/main.go
+++ b/src/cmd/gofix/main.go
@@ -40,7 +40,7 @@ func usage() {
 	fmt.Fprintf(os.Stderr, "usage: gofix [-diff] [-r fixname,...] [-force fixname,...] [path ...]\n")
 	flag.PrintDefaults()
 	fmt.Fprintf(os.Stderr, "\nAvailable rewrites are:\n")
-	sort.Sort(fixes)
+	sort.Sort(byName(fixes))
 	for _, f := range fixes {
 		fmt.Fprintf(os.Stderr, "\n%s\n", f.name)
 		desc := strings.TrimSpace(f.desc)
@@ -54,6 +54,8 @@ func main() {
 	flag.Usage = usage
 	flag.Parse()
 
+	sort.Sort(byDate(fixes))
+
 	if *allowedRewrites != "" {
 		allowed = make(map[string]bool)
 		for _, f := range strings.Split(*allowedRewrites, ",") {
diff --git a/src/cmd/gofix/mapdelete.go b/src/cmd/gofix/mapdelete.go
index b99602dcc2..db89c7bf45 100644
--- a/src/cmd/gofix/mapdelete.go
+++ b/src/cmd/gofix/mapdelete.go
@@ -6,8 +6,13 @@ package main
 
 import "go/ast"
 
+func init() {
+	register(mapdeleteFix)
+}
+
 var mapdeleteFix = fix{
 	"mapdelete",
+	"2011-10-18",
 	mapdelete,
 	`Use delete(m, k) instead of m[k] = 0, false.
 
diff --git a/src/cmd/gofix/math.go b/src/cmd/gofix/math.go
index a9a11ed615..2ec837eb00 100644
--- a/src/cmd/gofix/math.go
+++ b/src/cmd/gofix/math.go
@@ -6,8 +6,13 @@ package main
 
 import "go/ast"
 
+func init() {
+	register(mathFix)
+}
+
 var mathFix = fix{
 	"math",
+	"2011-09-29",
 	math,
 	`Remove the leading F from math functions such as Fabs.
 
diff --git a/src/cmd/gofix/netdial.go b/src/cmd/gofix/netdial.go
index 6984cdc372..2de994cffe 100644
--- a/src/cmd/gofix/netdial.go
+++ b/src/cmd/gofix/netdial.go
@@ -8,8 +8,15 @@ import (
 	"go/ast"
 )
 
+func init() {
+	register(netdialFix)
+	register(tlsdialFix)
+	register(netlookupFix)
+}
+
 var netdialFix = fix{
 	"netdial",
+	"2011-03-28",
 	netdial,
 	`Adapt 3-argument calls of net.Dial to use 2-argument form.
 
@@ -19,6 +26,7 @@ http://codereview.appspot.com/4244055
 
 var tlsdialFix = fix{
 	"tlsdial",
+	"2011-03-28",
 	tlsdial,
 	`Adapt 4-argument calls of tls.Dial to use 3-argument form.
 
@@ -28,6 +36,7 @@ http://codereview.appspot.com/4244055
 
 var netlookupFix = fix{
 	"netlookup",
+	"2011-03-28",
 	netlookup,
 	`Adapt 3-result calls to net.LookupHost to use 2-result form.
 
diff --git a/src/cmd/gofix/netudpgroup.go b/src/cmd/gofix/netudpgroup.go
index 9bbb2d7919..12a2efa287 100644
--- a/src/cmd/gofix/netudpgroup.go
+++ b/src/cmd/gofix/netudpgroup.go
@@ -8,8 +8,13 @@ import (
 	"go/ast"
 )
 
+func init() {
+	register(netudpgroupFix)
+}
+
 var netudpgroupFix = fix{
 	"netudpgroup",
+	"2011-08-18",
 	netudpgroup,
 	`Adapt 1-argument calls of net.(*UDPConn).JoinGroup, LeaveGroup to use 2-argument form.
 
diff --git a/src/cmd/gofix/oserrorstring.go b/src/cmd/gofix/oserrorstring.go
index 416333fc12..a75a2c12d3 100644
--- a/src/cmd/gofix/oserrorstring.go
+++ b/src/cmd/gofix/oserrorstring.go
@@ -8,8 +8,13 @@ import (
 	"go/ast"
 )
 
+func init() {
+	register(oserrorstringFix)
+}
+
 var oserrorstringFix = fix{
 	"oserrorstring",
+	"2011-06-22",
 	oserrorstring,
 	`Replace os.ErrorString() conversions with calls to os.NewError().
 
diff --git a/src/cmd/gofix/osopen.go b/src/cmd/gofix/osopen.go
index 7e7fbbb037..af2796ac22 100644
--- a/src/cmd/gofix/osopen.go
+++ b/src/cmd/gofix/osopen.go
@@ -8,8 +8,13 @@ import (
 	"go/ast"
 )
 
+func init() {
+	register(osopenFix)
+}
+
 var osopenFix = fix{
 	"osopen",
+	"2011-04-04",
 	osopen,
 	`Adapt os.Open calls to new, easier API and rename O_CREAT O_CREATE.
 
diff --git a/src/cmd/gofix/procattr.go b/src/cmd/gofix/procattr.go
index 86a8fd1035..ea375ec9dd 100644
--- a/src/cmd/gofix/procattr.go
+++ b/src/cmd/gofix/procattr.go
@@ -9,8 +9,13 @@ import (
 	"go/token"
 )
 
+func init() {
+	register(procattrFix)
+}
+
 var procattrFix = fix{
 	"procattr",
+	"2011-03-15",
 	procattr,
 	`Adapt calls to os.StartProcess to use new ProcAttr type.
 
diff --git a/src/cmd/gofix/reflect.go b/src/cmd/gofix/reflect.go
index 2227d69b44..6670ef2774 100644
--- a/src/cmd/gofix/reflect.go
+++ b/src/cmd/gofix/reflect.go
@@ -15,8 +15,13 @@ import (
 	"strings"
 )
 
+func init() {
+	register(reflectFix)
+}
+
 var reflectFix = fix{
 	"reflect",
+	"2011-04-08",
 	reflectFn,
 	`Adapt code to new reflect API.
 
diff --git a/src/cmd/gofix/signal.go b/src/cmd/gofix/signal.go
index 9b548bd089..5a583d41e9 100644
--- a/src/cmd/gofix/signal.go
+++ b/src/cmd/gofix/signal.go
@@ -9,8 +9,13 @@ import (
 	"strings"
 )
 
+func init() {
+	register(signalFix)
+}
+
 var signalFix = fix{
 	"signal",
+	"2011-06-29",
 	signal,
 	`Adapt code to types moved from os/signal to signal.
 
diff --git a/src/cmd/gofix/sorthelpers.go b/src/cmd/gofix/sorthelpers.go
index 74d0daa3a9..fa549313eb 100644
--- a/src/cmd/gofix/sorthelpers.go
+++ b/src/cmd/gofix/sorthelpers.go
@@ -8,8 +8,13 @@ import (
 	"go/ast"
 )
 
+func init() {
+	register(sorthelpersFix)
+}
+
 var sorthelpersFix = fix{
 	"sorthelpers",
+	"2011-07-08",
 	sorthelpers,
 	`Adapt code from sort.Sort[Ints|Float64s|Strings] to sort.[Ints|Float64s|Strings].
 `,
diff --git a/src/cmd/gofix/sortslice.go b/src/cmd/gofix/sortslice.go
index 847f0d57fb..89267b847e 100644
--- a/src/cmd/gofix/sortslice.go
+++ b/src/cmd/gofix/sortslice.go
@@ -8,8 +8,13 @@ import (
 	"go/ast"
 )
 
+func init() {
+	register(sortsliceFix)
+}
+
 var sortsliceFix = fix{
 	"sortslice",
+	"2011-06-26",
 	sortslice,
 	`Adapt code from sort.[Float64|Int|String]Array to  sort.[Float64|Int|String]Slice.
 		
diff --git a/src/cmd/gofix/stringssplit.go b/src/cmd/gofix/stringssplit.go
index e3886dd729..d89ecf039c 100644
--- a/src/cmd/gofix/stringssplit.go
+++ b/src/cmd/gofix/stringssplit.go
@@ -9,8 +9,13 @@ import (
 	"go/token"
 )
 
+func init() {
+	register(stringssplitFix)
+}
+
 var stringssplitFix = fix{
 	"stringssplit",
+	"2011-06-28",
 	stringssplit,
 	`Restore strings.Split to its original meaning and add strings.SplitN. Bytes too.
 
diff --git a/src/cmd/gofix/url.go b/src/cmd/gofix/url.go
index d90f2b0cc1..49aac739b3 100644
--- a/src/cmd/gofix/url.go
+++ b/src/cmd/gofix/url.go
@@ -6,8 +6,13 @@ package main
 
 import "go/ast"
 
+func init() {
+	register(urlFix)
+}
+
 var urlFix = fix{
 	"url",
+	"2011-08-17",
 	url,
 	`Move the URL pieces of package http into a new package, url.
 
-- 
2.50.0