From 4f84e07a1b11db9394bb86b72a6c677a718a04d3 Mon Sep 17 00:00:00 2001
From: rubyist <scott.barron@github.com>
Date: Mon, 20 Oct 2014 14:49:15 -0400
Subject: [PATCH] Make `push` use the scanner

---
 commands/command_ls_files.go |  2 +-
 commands/command_push.go     | 35 +++++++++--------------------------
 scanner/scanner.go           | 14 ++++++++++----
 3 files changed, 20 insertions(+), 31 deletions(-)

diff --git a/commands/command_ls_files.go b/commands/command_ls_files.go
index e9456159..a57990a4 100644
--- a/commands/command_ls_files.go
+++ b/commands/command_ls_files.go
@@ -27,7 +27,7 @@ func lsFilesCommand(cmd *cobra.Command, args []string) {
 		}
 	}
 
-	pointers, err := scanner.Scan(ref)
+	pointers, err := scanner.Scan(ref, "")
 	if err != nil {
 		Panic(err, "Could not scan for git media files")
 	}
diff --git a/commands/command_push.go b/commands/command_push.go
index a5ceceed..6b7e79e5 100644
--- a/commands/command_push.go
+++ b/commands/command_push.go
@@ -4,7 +4,7 @@ import (
 	"github.com/github/git-media/git"
 	"github.com/github/git-media/gitmedia"
 	"github.com/github/git-media/gitmediaclient"
-	"github.com/github/git-media/pointer"
+	"github.com/github/git-media/scanner"
 	"github.com/rubyist/tracerx"
 	"github.com/spf13/cobra"
 	"io/ioutil"
@@ -105,14 +105,18 @@ func pushCommand(cmd *cobra.Command, args []string) {
 		}
 	}
 
-	links := linksFromRefs(left, right)
+	// Just use scanner here
+	pointers, err := scanner.Scan(left, right)
+	if err != nil {
+		Panic(err, "Error scanning for media files")
+	}
 
-	for i, link := range links {
+	for i, pointer := range pointers {
 		if dryRun {
-			Print("push %s", link.Name)
+			Print("push %s", pointer.Name)
 			continue
 		}
-		if wErr := pushAsset(link.Oid, link.Name, i+1, len(links)); wErr != nil {
+		if wErr := pushAsset(pointer.Oid, pointer.Name, i+1, len(pointers)); wErr != nil {
 			Panic(wErr.Err, wErr.Error())
 		}
 	}
@@ -168,27 +172,6 @@ func decodeRefs(input string) (string, string) {
 	return left, right
 }
 
-// linksFromRefs runs git.RevListObjects for the passed refs and builds
-// a slice of pointer.Link's for any object that has an associated git media file.
-func linksFromRefs(left, right string) []*pointer.Link {
-	revList, err := git.RevListObjects(left, right, false)
-	if err != nil {
-		Panic(err, "Error running git rev-list --objects %s %s", left, right)
-	}
-
-	links := make([]*pointer.Link, 0)
-	for _, object := range revList {
-		link, err := pointer.FindLink(object.Sha1)
-		if err != nil {
-			continue
-		}
-
-		links = append(links, link)
-	}
-
-	return links
-}
-
 func init() {
 	pushCmd.Flags().BoolVarP(&dryRun, "dry-run", "d", false, "Do everything except actually send the updates")
 	pushCmd.Flags().BoolVarP(&useStdin, "stdin", "s", false, "Take refs on stdin (for pre-push hook)")
diff --git a/scanner/scanner.go b/scanner/scanner.go
index 64172a81..bf54975a 100644
--- a/scanner/scanner.go
+++ b/scanner/scanner.go
@@ -7,6 +7,7 @@ import (
 	"github.com/rubyist/tracerx"
 	"io"
 	"os/exec"
+	"regexp"
 	"strconv"
 	"strings"
 	"time"
@@ -34,13 +35,15 @@ type wrappedPointer struct {
 	*pointer.Pointer
 }
 
+var z40 = regexp.MustCompile(`\^?0{40}`)
+
 // Scan takes a ref and returns a slice of pointer.Pointer objects
 // for all git media pointers it finds for that ref.
-func Scan(ref string) ([]*wrappedPointer, error) {
+func Scan(refLeft, refRight string) ([]*wrappedPointer, error) {
 	nameMap := make(map[string]string, 0)
 	start := time.Now()
 
-	revs, err := revListShas(ref, ref == "", nameMap)
+	revs, err := revListShas(refLeft, refRight, refLeft == "", nameMap)
 	if err != nil {
 		return nil, err
 	}
@@ -71,13 +74,16 @@ func Scan(ref string) ([]*wrappedPointer, error) {
 // revListShas uses git rev-list to return the list of object sha1s
 // for the given ref. If all is true, ref is ignored. It returns a
 // channel from which sha1 strings can be read.
-func revListShas(ref string, all bool, nameMap map[string]string) (chan string, error) {
+func revListShas(refLeft, refRight string, all bool, nameMap map[string]string) (chan string, error) {
 	refArgs := []string{"rev-list", "--objects"}
 	if all {
 		refArgs = append(refArgs, "--all")
 	} else {
 		refArgs = append(refArgs, "--no-walk")
-		refArgs = append(refArgs, ref)
+		refArgs = append(refArgs, refLeft)
+		if refRight != "" && !z40.MatchString(refRight) {
+			refArgs = append(refArgs, refRight)
+		}
 	}
 
 	cmd, err := startCommand("git", refArgs...)