Comment # 6 on bug 954556 from Tony Mechelynck

# hg fetch --switch-parent || echo 'exit status' $? ; date
pulling from https://bitbucket.org/vim-mirror/vim
searching for changes
sampling from both directions
adding changesets
adding manifests
adding file changes
added 5 changesets with 17 changes to 15 files (+1 heads)
resolving manifests
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
merging with 7362:444efa5f5015
resolving manifests
runtime/doc/tags: untracked file differs
abort: untracked files in working directory differ from files in requested
revision
exit status 255
Sun  6 Dec 07:00:18 CET 2015

Inspection showed that "hg fetch" had pulled the new changesets but not merged
the new tip with the current revision or changed which revision was current (an
automated merge from a previous fetch which hadn't changed the untracked file).
Updating to the new tip or to its common ancestor with the current revision was
not possible except after manually deleting the untracked file.

After manually deleting the untracked file (and nothing else, in particular no
commit yet), Mercurial accepted to update to the new tip and back, and then:

# hg merge -r tip
resolving manifests
remote changed runtime/doc/tags which local deleted
use (c)hanged version or leave (d)eleted? d
getting .hgtags
getting runtime/doc/eval.txt
getting runtime/doc/filetype.txt
getting runtime/doc/if_ruby.txt
getting runtime/doc/todo.txt
getting runtime/syntax/r.vim
getting runtime/syntax/vhdl.vim
getting runtime/syntax/vim.vim
getting src/normal.c
getting src/proto/window.pro
getting src/testdir/Makefile
getting src/version.c
getting src/window.c
merging src/Makefile
13 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
# hg commit -m 'manual merge'
committing files:
.hgtags
runtime/doc/eval.txt
runtime/doc/filetype.txt
runtime/doc/if_ruby.txt
runtime/doc/todo.txt
runtime/syntax/r.vim
runtime/syntax/vhdl.vim
runtime/syntax/vim.vim
src/Makefile
src/normal.c
src/proto/window.pro
src/testdir/Makefile
src/version.c
src/window.c
committing manifest
committing changelog
committed changeset 7363:439f55eac0c0