Merge branch 'en/rebase-against-rebase-fix'

* en/rebase-against-rebase-fix:
  pull --rebase: Avoid spurious conflicts and reapplying unnecessary patches
  t5520-pull: Add testcases showing spurious conflicts from git pull --rebase

diff --combined git-pull.sh
index a09a44ec4ce3d82cebc5f972f09e94c7c35dc948,5dbc4387f75658689bae24c294159bd91ed5c544..8eb74d45debe7ab2bd2cc9b5ed57b1ba49d94bdb
--- 1/git-pull.sh
--- 2/git-pull.sh
+++ b/git-pull.sh
@@@ -38,12 -38,11 +38,12 @@@ test -z "$(git ls-files -u)" || die_con
  test -f "$GIT_DIR/MERGE_HEAD" && die_merge
  
  strategy_args= diffstat= no_commit= squash= no_ff= ff_only=
 -log_arg= verbosity=
 +log_arg= verbosity= progress=
  merge_args=
  curr_branch=$(git symbolic-ref -q HEAD)
 -curr_branch_short=$(echo "$curr_branch" | sed "s|refs/heads/||")
 +curr_branch_short="${curr_branch#refs/heads/}"
  rebase=$(git config --bool branch.$curr_branch_short.rebase)
 +dry_run=
  while :
  do
        case "$1" in
@@@ -51,8 -50,6 +51,8 @@@
                verbosity="$verbosity -q" ;;
        -v|--verbose)
                verbosity="$verbosity -v" ;;
 +      --progress)
 +              progress=--progress ;;
        -n|--no-stat|--no-summary)
                diffstat=--no-stat ;;
        --stat|--summary)
@@@ -105,9 -102,6 +105,9 @@@
        --no-r|--no-re|--no-reb|--no-reba|--no-rebas|--no-rebase)
                rebase=false
                ;;
 +      --d|--dr|--dry|--dry-|--dry-r|--dry-ru|--dry-run)
 +              dry_run=--dry-run
 +              ;;
        -h|--h|--he|--hel|--help)
                usage
                ;;
@@@ -220,8 -214,7 +220,8 @@@ test true = "$rebase" && 
        done
  }
  orig_head=$(git rev-parse -q --verify HEAD)
 -git fetch $verbosity --update-head-ok "$@" || exit 1
 +git fetch $verbosity $progress $dry_run --update-head-ok "$@" || exit 1
 +test -z "$dry_run" || exit 0
  
  curr_head=$(git rev-parse -q --verify HEAD)
  if test -n "$orig_head" && test "$curr_head" != "$orig_head"
@@@ -273,6 -266,15 +273,15 @@@ the
        exit
  fi
  
+ if test true = "$rebase"
+ then
+       o=$(git show-branch --merge-base $curr_branch $merge_head $oldremoteref)
+       if test "$oldremoteref" = "$o"
+       then
+               unset oldremoteref
+       fi
+ fi
+ 
  merge_name=$(git fmt-merge-msg $log_arg <"$GIT_DIR/FETCH_HEAD") || exit
  case "$rebase" in
  true)

diff --combined t/t5520-pull.sh
index 319e389ed0dbb9c920d8d619cdf94ab52145e9f4,eee6f6d9cce18178037191a4222ef9477461ab8c..0b489f5b1227268c050c1256d105d57d871f5698
--- 1/t/t5520-pull.sh
--- 2/t/t5520-pull.sh
+++ b/t/t5520-pull.sh
@@@ -4,6 -4,11 +4,11 @@@ test_description='pulling into void
  
  . ./test-lib.sh
  
+ modify () {
+       sed -e "$1" <"$2" >"$2.x" &&
+       mv "$2.x" "$2"
+ }
+ 
  D=`pwd`
  
  test_expect_success setup '
@@@ -26,7 -31,7 +31,7 @@@ cd "$D
  test_expect_success 'checking the results' '
        test -f file &&
        test -f cloned/file &&
 -      diff file cloned/file
 +      test_cmp file cloned/file
  '
  
  test_expect_success 'pulling into void using master:master' '
@@@ -160,4 -165,61 +165,61 @@@ test_expect_success 'pull --rebase work
        test_cmp expect actual
  '
  
+ test_expect_success 'setup for detecting upstreamed changes' '
+       mkdir src &&
+       (cd src &&
+        git init &&
+        printf "1\n2\n3\n4\n5\n6\n7\n8\n9\n10\n" > stuff &&
+        git add stuff &&
+        git commit -m "Initial revision"
+       ) &&
+       git clone src dst &&
+       (cd src &&
+        modify s/5/43/ stuff &&
+        git commit -a -m "5->43" &&
+        modify s/6/42/ stuff &&
+        git commit -a -m "Make it bigger"
+       ) &&
+       (cd dst &&
+        modify s/5/43/ stuff &&
+        git commit -a -m "Independent discovery of 5->43"
+       )
+ '
+ 
+ test_expect_success 'git pull --rebase detects upstreamed changes' '
+       (cd dst &&
+        git pull --rebase &&
+        test -z "$(git ls-files -u)"
+       )
+ '
+ 
+ test_expect_success 'setup for avoiding reapplying old patches' '
+       (cd dst &&
+        test_might_fail git rebase --abort &&
+        git reset --hard origin/master
+       ) &&
+       git clone --bare src src-replace.git &&
+       rm -rf src &&
+       mv src-replace.git src &&
+       (cd dst &&
+        modify s/2/22/ stuff &&
+        git commit -a -m "Change 2" &&
+        modify s/3/33/ stuff &&
+        git commit -a -m "Change 3" &&
+        modify s/4/44/ stuff &&
+        git commit -a -m "Change 4" &&
+        git push &&
+ 
+        modify s/44/55/ stuff &&
+        git commit --amend -a -m "Modified Change 4"
+       )
+ '
+ 
+ test_expect_success 'git pull --rebase does not reapply old patches' '
+       (cd dst &&
+        test_must_fail git pull --rebase &&
+        test 1 = $(find .git/rebase-apply -name "000*" | wc -l)
+       )
+ '
+ 
  test_done