lib/oe/patch.py: Prefer "git am" over "git apply" when applying git patches

It is better to use "git am" when possible to preserve the commit messages and
the mail format in general for patches when those are present. A typical use
case is when developers would like to keep the changes on top of the latest
upstream, and they may occasionally need to rebase. This is not possible with
"git diff" and "diff" generated patches.

Since this is not always the case, the fallback would be the "git apply"
operation which is currently available.

Signed-off-by: Laszlo Papp <lpapp@kde.org>
Signed-off-by: Saul Wold <sgw@linux.intel.com>

diff --git a/meta/lib/oe/patch.py b/meta/lib/oe/patch.py
index 59abd0af19748730e370f575d5740e701c4edbb2..b085c9d6b538aaf6b22735c57617e1fad0adc253 100644 (file)
--- a/meta/lib/oe/patch.py
+++ b/meta/lib/oe/patch.py
@@ -203,17 +203,23 @@ class GitApplyTree(PatchTree):
         PatchTree.__init__(self, dir, d)
 
     def _applypatch(self, patch, force = False, reverse = False, run = True):
-        shellcmd = ["git", "--git-dir=.", "apply", "-p%s" % patch['strippath']]
+        def _applypatchhelper(shellcmd, patch, force = False, reverse = False, run = True):
+            if reverse:
+                shellcmd.append('-R')
 
-        if reverse:
-            shellcmd.append('-R')
+            shellcmd.append(patch['file'])
 
-        shellcmd.append(patch['file'])
+            if not run:
+                return "sh" + "-c" + " ".join(shellcmd)
 
-        if not run:
-            return "sh" + "-c" + " ".join(shellcmd)
+            return runcmd(["sh", "-c", " ".join(shellcmd)], self.dir)
 
-        return runcmd(["sh", "-c", " ".join(shellcmd)], self.dir)
+        try:
+            shellcmd = ["git", "--work-tree=.", "am", "-3", "-p%s" % patch['strippath']]
+            return _applypatchhelper(shellcmd, patch, force, reverse, run)
+        except CmdError:
+            shellcmd = ["git", "--git-dir=.", "apply", "-p%s" % patch['strippath']]
+            return _applypatchhelper(shellcmd, patch, force, reverse, run)
 
 
 class QuiltTree(PatchSet):