comparison tests/test-fix.t @ 42756:ed0da6e0d6ee

fix: allow tools to use :linerange, but also run if a file is unchanged

The definition of "unchanged" here is subtle, because pure deletion diff hunks
are ignored. That means this is different from using the --whole flag. This
change allows you to configure, for example, a code formatter that:
 1. Formats specific line ranges if specified via flags
 2. Does not format the entire file when there are no line ranges provided
 3. Performs some other kind of formatting regardless of provided line ranges

This sounds a little far fetched, but it is meant to address a specific corner
case encountered in Google's use of the fix extension. The default behavior is
kept because it exists to prevent mistakes that could erase uncommitted
changes.

Differential Revision: https://phab.mercurial-scm.org/D6723

42755:749ef8c31187

  substituted into the command:
  
    {first}   The 1-based line number of the first line in the modified range
    {last}    The 1-based line number of the last line in the modified range
  
  The :pattern suboption determines which files will be passed through each
  configured tool. See 'hg help patterns' for possible values. If there are file
  arguments to 'hg fix', the intersection of these patterns is used.
  
  There is also a configurable limit for the maximum size of file that will be

  fixed
  $ cat baz_file
  fixed

  $ cd ..

42756:ed0da6e0d6ee

  substituted into the command:
  
    {first}   The 1-based line number of the first line in the modified range
    {last}    The 1-based line number of the last line in the modified range
  
  Deleted sections of a file will be ignored by :linerange, because there is no
  corresponding line range in the version being fixed.
  
  By default, tools that set :linerange will only be executed if there is at
  least one changed line range. This is meant to prevent accidents like running
  a code formatter in such a way that it unexpectedly reformats the whole file.
  If such a tool needs to operate on unchanged files, it should set the
  :skipclean suboption to false.
  
  The :pattern suboption determines which files will be passed through each
  configured tool. See 'hg help patterns' for possible values. If there are file
  arguments to 'hg fix', the intersection of these patterns is used.
  
  There is also a configurable limit for the maximum size of file that will be

  fixed
  $ cat baz_file
  fixed

  $ cd ..

Tools should be able to run on unchanged files, even if they set :linerange.
This includes a corner case where deleted chunks of a file are not considered
changes.

  $ hg init skipclean
  $ cd skipclean

  $ printf "a\nb\nc\n" > foo
  $ printf "a\nb\nc\n" > bar
  $ printf "a\nb\nc\n" > baz
  $ hg commit -Aqm "base"

  $ printf "a\nc\n" > foo
  $ printf "a\nx\nc\n" > baz

  $ hg fix --working-dir foo bar baz \
  >        --config 'fix.changedlines:command=printf "Line ranges:\n"; ' \
  >        --config 'fix.changedlines:linerange=printf "{first} through {last}\n"; ' \
  >        --config 'fix.changedlines:pattern=rootglob:**' \
  >        --config 'fix.changedlines:skipclean=false'

  $ cat foo
  Line ranges:
  $ cat bar
  Line ranges:
  $ cat baz
  Line ranges:
  2 through 2

  $ cd ..