Merge branch 'jc/am-3-nonstandard-popt' into maint

The code to synthesize the fake ancestor tree used by 3-way merge
fallback in "git am" was not prepared to read a patch created with
a non-standard -p<num> value.

* jc/am-3-nonstandard-popt:
test: "am -3" can accept non-standard -p<num>
am -3: allow nonstandard -p<num> option

diff --combined git-am.sh
index f43a75b04bf692b9ff6acaae0f6bbe51369aa399,d5d168fc51b8787cb6293758e24435876bb82e31..cb833e217ae90ebfe2f5ed1710d4372906bdfe3e
--- 1/git-am.sh
--- 2/git-am.sh
+++ b/git-am.sh
@@@ -127,15 -127,18 +127,18 @@@ fall_back_3way () 
      mkdir "$dotest/patch-merge-tmp-dir"
  
      # First see if the patch records the index info that we can use.
-     git apply --build-fake-ancestor "$dotest/patch-merge-tmp-index" \
-       "$dotest/patch" &&
+     cmd="git apply $git_apply_opt --build-fake-ancestor" &&
+     cmd="$cmd "'"$dotest/patch-merge-tmp-index" "$dotest/patch"' &&
+     eval "$cmd" &&
      GIT_INDEX_FILE="$dotest/patch-merge-tmp-index" \
      git write-tree >"$dotest/patch-merge-base+" ||
      cannot_fallback "$(gettext "Repository lacks necessary blobs to fall back on 3-way merge.")"
  
      say Using index info to reconstruct a base tree...
-     if GIT_INDEX_FILE="$dotest/patch-merge-tmp-index" \
-       git apply --cached <"$dotest/patch"
+ 
+     cmd='GIT_INDEX_FILE="$dotest/patch-merge-tmp-index"'
+     cmd="$cmd git apply --cached $git_apply_opt"' <"$dotest/patch"'
+     if eval "$cmd"
      then
        mv "$dotest/patch-merge-base+" "$dotest/patch-merge-base"
        mv "$dotest/patch-merge-tmp-index" "$dotest/patch-merge-index"
@@@ -201,7 -204,7 +204,7 @@@ check_patch_format () 
                l1=
                while test -z "$l1"
                do
 -                      read l1
 +                      read l1 || break
                done
                read l2
                read l3

diff --combined t/t4150-am.sh
index 00d669a3c9bbf3329cf800fc15147770a45e6a4b,e1d381c43bedad287f4ff430c1b65756e1dc2c99..658354a6ce8ab13fd6b229bb2adecd8e29de9697
--- 1/t/t4150-am.sh
--- 2/t/t4150-am.sh
+++ b/t/t4150-am.sh
@@@ -123,6 -123,7 +123,7 @@@ test_expect_success setup 
        git commit -m "added another file" &&
  
        git format-patch --stdout master >lorem-move.patch &&
+       git format-patch --no-prefix --stdout master >lorem-zero.patch &&
  
        git checkout -b rename &&
        git mv file renamed &&
@@@ -136,7 -137,7 +137,7 @@@
        git format-patch -M --stdout lorem^ >rename-add.patch &&
  
        # reset time
 -      unset test_tick &&
 +      sane_unset test_tick &&
        test_tick
  '
  
@@@ -276,6 -277,20 +277,20 @@@ test_expect_success 'am -3 falls back t
        git diff --exit-code lorem
  '
  
+ test_expect_success 'am -3 -p0 can read --no-prefix patch' '
+       rm -fr .git/rebase-apply &&
+       git reset --hard &&
+       git checkout -b lorem3 master2 &&
+       sed -n -e "3,\$p" msg >file &&
+       head -n 9 msg >>file &&
+       git add file &&
+       test_tick &&
+       git commit -m "copied stuff" &&
+       git am -3 -p0 lorem-zero.patch &&
+       ! test -d .git/rebase-apply &&
+       git diff --exit-code lorem
+ '
+ 
  test_expect_success 'am can rename a file' '
        grep "^rename from" rename.patch &&
        rm -fr .git/rebase-apply &&
@@@ -495,14 -510,4 +510,14 @@@ test_expect_success 'am -q is quiet' 
        ! test -s output.out
  '
  
 +test_expect_success 'am empty-file does not infloop' '
 +      rm -fr .git/rebase-apply &&
 +      git reset --hard &&
 +      touch empty-file &&
 +      test_tick &&
 +      { git am empty-file > actual 2>&1 && false || :; } &&
 +      echo Patch format detection failed. >expected &&
 +      test_cmp expected actual
 +'
 +
  test_done