mercurial: add editorconfig
Editorconfig (http://editorconfig.org/) is a file format helping define coding
styles like spaces, tabs etc. It supports a wide range of editors. Some well-
known projects like ruby and zsh are using it already.
This patch adds a simple .editorconfig, making it clear we use 8-char tabs in
C code, 4-char spaces in Python code, and we don't keep trailing spaces.
$ hg init
$ echo a > a
$ hg ci -qAm 'add a'
$ hg init subrepo
$ echo 'subrepo = http://example.net/libfoo' > .hgsub
$ hg ci -qAm 'added subrepo'
$ hg up -qC 0
$ echo ax > a
$ hg ci -m 'changed a'
created new head
$ hg up -qC 1
$ cd subrepo
$ echo b > b
$ hg add b
$ cd ..
Should fail, since there are added files to subrepo:
$ hg merge
abort: uncommitted changes in subrepository 'subrepo'
[255]