merge: disable path conflict checking by default (issue5716)

We shouldn't ship a severe perf regression in hg update for 4.4.

Differential Revision: https://phab.mercurial-scm.org/D1223

mercurial/configitems.py

@@ -579,7 +579,7 b" coreconfigitem('merge', 'checkignored',"
     default='abort',
 )
 coreconfigitem('experimental', 'merge.checkpathconflicts',
-    default=True,
+    default=False,
 )
 coreconfigitem('merge', 'followcopies',
     default=True,

tests/test-audit-path.t

@@ -104,8 +104,7 b' attack back/test where back symlinks to '
   back/test
 #if symlink
   $ hg update -Cr2
-  back: is both a file and a directory
-  abort: destination manifest contains path conflicts
+  abort: path 'back/test' traverses symbolic link 'back'
   [255]
 #else
 ('back' will be a file and cause some other system specific error)
@@ -167,12 +166,8 b' try trivial merge'
 
   $ hg up -qC 1
   $ hg merge 2
-  a: path conflict - a file or link has the same name as a directory
-  the local file has been renamed to a~aa04623eb0c3
-  resolve manually then use 'hg resolve --mark a'
-  1 files updated, 0 files merged, 0 files removed, 1 files unresolved
-  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
-  [1]
+  abort: path 'a/poisoned' traverses symbolic link 'a'
+  [255]
 
 try rebase onto other revision: cache of audited paths should be discarded,
 and the rebase should fail (issue5628)
@@ -180,11 +175,8 b' and the rebase should fail (issue5628)'
   $ hg up -qC 2
   $ hg rebase -s 2 -d 1 --config extensions.rebase=
   rebasing 2:e73c21d6b244 "file a/poisoned" (tip)
-  a: path conflict - a file or link has the same name as a directory
-  the local file has been renamed to a~aa04623eb0c3
-  resolve manually then use 'hg resolve --mark a'
-  unresolved conflicts (see hg resolve, then hg rebase --continue)
-  [1]
+  abort: path 'a/poisoned' traverses symbolic link 'a'
+  [255]
   $ ls ../merge-symlink-out
 
   $ cd ..
@@ -216,8 +208,7 b' try linear update where symlink already '
 
   $ hg up -qC 0
   $ hg up 1
-  a: is both a file and a directory
-  abort: destination manifest contains path conflicts
+  abort: path 'a/b' traverses symbolic link 'a'
   [255]
 
 try linear update including symlinked directory and its content: paths are
@@ -226,8 +217,7 b' audited first by calculateupdates(), whe'
 
   $ hg up -qC null
   $ hg up 1
-  a: is both a file and a directory
-  abort: destination manifest contains path conflicts
+  abort: path 'a/b' traverses symbolic link 'a'
   [255]
   $ ls ../update-symlink-out
 
@@ -238,8 +228,7 b' a symlink.'
   $ rm -f a
   $ hg up -qC 2
   $ hg up 1
-  a: is both a file and a directory
-  abort: destination manifest contains path conflicts
+  abort: path 'a/b' traverses symbolic link 'a'
   [255]
   $ ls ../update-symlink-out
 

tests/test-commandserver.t

@@ -975,12 +975,8 b' and the merge should fail (issue5628)'
   *** runcommand up -qC 2
   *** runcommand up -qC 1
   *** runcommand merge 2
-  a: path conflict - a file or link has the same name as a directory
-  the local file has been renamed to a~aa04623eb0c3
-  resolve manually then use 'hg resolve --mark a'
-  1 files updated, 0 files merged, 0 files removed, 1 files unresolved
-  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
-   [1]
+  abort: path 'a/poisoned' traverses symbolic link 'a'
+   [255]
   $ ls ../merge-symlink-out
 
 cache of repo.auditor should be discarded, so matcher would never traverse

tests/test-merge1.t

@@ -30,22 +30,23 b" of the files in a commit we're updating "
 
   $ mkdir b && touch b/nonempty
   $ hg up
-  b: untracked directory conflicts with file
-  abort: untracked files in working directory differ from files in requested revision
-  [255]
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg ci
   nothing changed
   [1]
   $ hg sum
-  parent: 0:538afb845929 
-   commit #0
+  parent: 1:b8bb4a988f25 tip
+   commit #1
   branch: default
-  commit: 1 unknown (clean)
-  update: 1 new changesets (update)
+  commit: (clean)
+  update: (current)
   phases: 2 draft
+
+The following line is commented out because the file doesn't exist at the moment, and some OSes error out even with `rm -f`.
   $ rm b/nonempty
+
   $ hg up
-  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg sum
   parent: 1:b8bb4a988f25 tip
    commit #1

tests/test-pathconflicts-basic.t

@@ -1,3 +1,11 b''
+Path conflict checking is currently disabled by default because of issue5716.
+Turn it on for this test.
+
+  $ cat >> $HGRCPATH << EOF
+  > [experimental]
+  > merge.checkpathconflicts=True
+  > EOF
+
   $ hg init repo
   $ cd repo
   $ echo base > base
@@ -96,4 +104,3 b' Repo state is ok'
   commit: (clean)
   update: 1 new changesets, 2 branch heads (merge)
   phases: 4 draft
-

tests/test-pathconflicts-merge.t

@@ -1,3 +1,11 b''
+Path conflict checking is currently disabled by default because of issue5716.
+Turn it on for this test.
+
+  $ cat >> $HGRCPATH << EOF
+  > [experimental]
+  > merge.checkpathconflicts=True
+  > EOF
+
   $ hg init repo
   $ cd repo
   $ echo base > base

tests/test-pathconflicts-update.t

@@ -1,3 +1,11 b''
+Path conflict checking is currently disabled by default because of issue5716.
+Turn it on for this test.
+
+  $ cat >> $HGRCPATH << EOF
+  > [experimental]
+  > merge.checkpathconflicts=True
+  > EOF
+
   $ hg init repo
   $ cd repo
   $ echo base > base
@@ -150,4 +158,3 b' Update clean - local directory conflicts'
   $ hg up file2 --clean
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   (activating bookmark file2)
-

tests/test-update-names.t

@@ -50,9 +50,7 b' make sure that this does not erase untra'
   $ hg st
   ? name/file
   $ hg up 1
-  name: untracked directory conflicts with file
-  abort: untracked files in working directory differ from files in requested revision
-  [255]
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ cd ..
 
 #if symlink