changeset 48782:c7dbfc363655

filemerge: when using in-memory merge, always put backup files in temp dir Before calling a merge tool, we create a backup of the local side of the merge. That file can be put in the working copy or in a temporary directory, depending on the user's config. When we're merging in memory, we don't want to write to the actual, on-disk working copy, so we write the file to the in-memory working copy instead. However, since we don't support external merge tools with in-memory merge, it makes no difference where the file is actually stored (and if we ever do add support for external merge tools, then the file clearly can't live in the in-memory working-copy object anyway). So, since it doesn't matter where the file is stored, we can simplify by always putting them in the system's temp directory. Differential Revision: https://phab.mercurial-scm.org/D12187
author Martin von Zweigbergk <martinvonz@google.com>
date Fri, 11 Feb 2022 21:39:55 -0800
parents 8dd5853eaa04
children 218154867575
files mercurial/filemerge.py
diffstat 1 files changed, 12 insertions(+), 25 deletions(-) [+]
line wrap: on
line diff
--- a/mercurial/filemerge.py	Tue Feb 15 20:18:57 2022 -0800
+++ b/mercurial/filemerge.py	Fri Feb 11 21:39:55 2022 -0800
@@ -877,7 +877,7 @@
     }
 
 
-def _makebackup(repo, ui, wctx, fcd):
+def _makebackup(repo, ui, fcd):
     """Makes and returns a filectx-like object for ``fcd``'s backup file.
 
     In addition to preserving the user's pre-existing modifications to `fcd`
@@ -894,30 +894,17 @@
     # merge -> filemerge). (I suspect the fileset import is the weakest link)
     from . import context
 
-    backup = scmutil.backuppath(ui, repo, fcd.path())
-    inworkingdir = backup.startswith(repo.wvfs.base) and not backup.startswith(
-        repo.vfs.base
-    )
-    if isinstance(fcd, context.overlayworkingfilectx) and inworkingdir:
-        # If the backup file is to be in the working directory, and we're
-        # merging in-memory, we must redirect the backup to the memory context
-        # so we don't disturb the working directory.
-        relpath = backup[len(repo.wvfs.base) + 1 :]
-        wctx[relpath].write(fcd.data(), fcd.flags())
-        return wctx[relpath]
+    if isinstance(fcd, context.overlayworkingfilectx):
+        # If we're merging in-memory, we're free to put the backup anywhere.
+        fd, backup = pycompat.mkstemp(b'hg-merge-backup')
+        with os.fdopen(fd, 'wb') as f:
+            f.write(fcd.data())
     else:
-        # Otherwise, write to wherever path the user specified the backups
-        # should go. We still need to switch based on whether the source is
-        # in-memory so we can use the fast path of ``util.copy`` if both are
-        # on disk.
-        if isinstance(fcd, context.overlayworkingfilectx):
-            util.writefile(backup, fcd.data())
-        else:
-            a = _workingpath(repo, fcd)
-            util.copyfile(a, backup)
-        # A arbitraryfilectx is returned, so we can run the same functions on
-        # the backup context regardless of where it lives.
-        return context.arbitraryfilectx(backup, repo=repo)
+        backup = scmutil.backuppath(ui, repo, fcd.path())
+        a = _workingpath(repo, fcd)
+        util.copyfile(a, backup)
+
+    return context.arbitraryfilectx(backup, repo=repo)
 
 
 @contextlib.contextmanager
@@ -1065,7 +1052,7 @@
             ui.warn(onfailure % fduipath)
         return 1, False
 
-    backup = _makebackup(repo, ui, wctx, fcd)
+    backup = _makebackup(repo, ui, fcd)
     r = 1
     try:
         internalmarkerstyle = ui.config(b'ui', b'mergemarkers')