tests/test-churn.t

log: add -L/--line-range option to follow file history by line range

We add an experimental -L/--line-range option to 'hg log' taking file patterns
along with a line range using the (new) FILE,FROMLINE-TOLINE syntax where FILE
may be a pattern (matching exactly one file). The resulting history is similar
to what the "followlines" revset except that, if --patch is specified,
only diff hunks within specified line range are shown.

Basically, this brings the CLI on par with what currently only exists in hgweb
through line selection in "file" and "annotate" views resulting in a file log
with filtered patch to only display followed line range.

The option may be specified multiple times and can be combined with --rev and
regular file patterns to further restrict revisions. Usage of this option
requires --follow; revisions are shown in descending order and renames are
followed. Only the --graph option is currently not supported.

The UI is the result of a consensus from review feedback at:

  https://www.mercurial-scm.org/pipermail/mercurial-devel/2017-October/106749.html


The implementation spreads between commands.log() and cmdutil module.
In commands.log(), the main loop may now use a "hunksfilter" factory (similar
to "filematcher") that, for a given "rev", produces a filtering function
for diff hunks for a given file context object.
The logic to build revisions from -L/--line-range options lives in
cmdutil.getloglinerangerevs() which produces "revs", "filematcher" and
"hunksfilter" information. Revisions obtained by following files' line range
are filtered if they do not match the revset specified by --rev option. If
regular FILE arguments are passed along with -L options, both filematchers are
combined into a new matcher.

.. feature::

   Add an experimental -L/--line-range FILE,FROMLINE-TOLINE option to 'hg log'
   command to follow the history of files by line range. In combination with
   -p/--patch option, only diff hunks within specified line range will be
   displayed. Feedback, especially on UX aspects, is welcome.

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "churn=" >> $HGRCPATH

create test repository

  $ hg init repo
  $ cd repo
  $ echo a > a
  $ hg ci -Am adda -u user1 -d 6:00
  adding a
  $ echo b >> a
  $ echo b > b
  $ hg ci -m changeba -u user2 -d 9:00 a
  $ hg ci -Am addb -u user2 -d 9:30
  adding b
  $ echo c >> a
  $ echo c >> b
  $ echo c > c
  $ hg ci -m changeca -u user3 -d 12:00 a
  $ hg ci -m changecb -u user3 -d 12:15 b
  $ hg ci -Am addc -u user3 -d 12:30
  adding c
  $ mkdir -p d/e
  $ echo abc > d/e/f1.txt
  $ hg ci -Am "add d/e/f1.txt" -u user1 -d 12:45 d/e/f1.txt
  $ mkdir -p d/g
  $ echo def > d/g/f2.txt
  $ hg ci -Am "add d/g/f2.txt" -u user1 -d 13:00 d/g/f2.txt


churn separate directories

  $ cd d
  $ hg churn e
  user1      1 ***************************************************************

churn all

  $ hg churn
  user1      3 ***************************************************************
  user3      3 ***************************************************************
  user2      2 ******************************************

churn excluding one dir

  $ hg churn -X e
  user3      3 ***************************************************************
  user1      2 ******************************************
  user2      2 ******************************************

churn up to rev 2

  $ hg churn -r :2
  user2      2 ***************************************************************
  user1      1 ********************************
  $ cd ..

churn with aliases

  $ cat > ../aliases <<EOF
  > user1 alias1
  > user3 alias3
  > not-an-alias
  > EOF

churn with .hgchurn

  $ mv ../aliases .hgchurn
  $ hg churn
  skipping malformed alias: not-an-alias
  alias1      3 **************************************************************
  alias3      3 **************************************************************
  user2       2 *****************************************
  $ rm .hgchurn

churn with column specifier

  $ COLUMNS=40 hg churn
  user1      3 ***********************
  user3      3 ***********************
  user2      2 ***************

churn by hour

  $ hg churn -f '%H' -s
  06      1 *****************
  09      2 *********************************
  12      4 ******************************************************************
  13      1 *****************


churn with separated added/removed lines

  $ hg rm d/g/f2.txt
  $ hg ci -Am "removed d/g/f2.txt" -u user1 -d 14:00 d/g/f2.txt
  $ hg churn --diffstat
  user1           +3/-1 +++++++++++++++++++++++++++++++++++++++++--------------
  user3           +3/-0 +++++++++++++++++++++++++++++++++++++++++
  user2           +2/-0 +++++++++++++++++++++++++++

churn --diffstat with color

  $ hg --config extensions.color= churn --config color.mode=ansi \
  >     --diffstat --color=always
  user1           +3/-1 \x1b[0;32m+++++++++++++++++++++++++++++++++++++++++\x1b[0m\x1b[0;31m--------------\x1b[0m (esc)
  user3           +3/-0 \x1b[0;32m+++++++++++++++++++++++++++++++++++++++++\x1b[0m (esc)
  user2           +2/-0 \x1b[0;32m+++++++++++++++++++++++++++\x1b[0m (esc)


changeset number churn

  $ hg churn -c
  user1      4 ***************************************************************
  user3      3 ***********************************************
  user2      2 ********************************

  $ echo 'with space = no-space' >> ../aliases
  $ echo a >> a
  $ hg commit -m a -u 'with space' -d 15:00

churn with space in alias

  $ hg churn --aliases ../aliases -r tip
  no-space      1 ************************************************************

  $ cd ..


Issue833: ZeroDivisionError

  $ hg init issue-833
  $ cd issue-833
  $ touch foo
  $ hg ci -Am foo
  adding foo

this was failing with a ZeroDivisionError

  $ hg churn
  test      0 
  $ cd ..

Ignore trailing or leading spaces in emails

  $ cd repo
  $ touch bar
  $ hg ci -Am'bar' -u 'user4 <[e-mail]>'
  adding bar
  $ touch foo
  $ hg ci -Am'foo' -u 'user4 < [e-mail] >'
  adding foo
  $ hg log -l2 --template '[{author|email}]\n'
  [ [e-mail] ]
  [[e-mail]]
  $ hg churn -c
  user1            4 *********************************************************
  user3            3 *******************************************
  user2            2 *****************************
  [e-mail]      2 *****************************
  with space       1 **************

Test multibyte sequences in names

  $ echo bar >> bar
  $ hg --encoding utf-8 ci -m'changed bar' -u 'El Niño <[e-mail]>'
  $ hg --encoding utf-8 churn -ct '{author|person}'
  user1           4 **********************************************************
  user3           3 ********************************************
  user2           2 *****************************
  user4           2 *****************************
  El Ni\xc3\xb1o         1 *************** (esc)
  with space      1 ***************

Test --template argument, with backwards compatibility

  $ hg churn -t '{author|user}'
  user1      4 ***************************************************************
  user3      3 ***********************************************
  user2      2 ********************************
  nino       1 ****************
  with       1 ****************
             0 
  user4      0 
  $ hg churn -T '{author|user}'
  user1      4 ***************************************************************
  user3      3 ***********************************************
  user2      2 ********************************
  nino       1 ****************
  with       1 ****************
             0 
  user4      0 
  $ hg churn -t 'alltogether'
  alltogether     11 *********************************************************
  $ hg churn -T 'alltogether'
  alltogether     11 *********************************************************

  $ cd ..