view mercurial/help/extensions.txt @ 23167:a3c2d9211294 stable

templater: don't overwrite the keyword mapping in runsymbol() (issue4362)

This keyword remapping was introduced in e06e9fd2d99f as part of converting
generator based iterators into list based iterators, mentioning "undesired
behavior in template" when a generator is exhausted, but doesn't say what and
introduces no tests.

The problem with the remapping was that it corrupted the output for keywords
like 'extras', 'file_copies' and 'file_copies_switch' in templates such as:

    $ hg log -r 142b5d5ec9cc --template "{file_copies % ' File: {file_copy}\n'}"
    File: mercurial/changelog.py (mercurial/hg.py)
    File: mercurial/changelog.py (mercurial/hg.py)
    File: mercurial/changelog.py (mercurial/hg.py)
    File: mercurial/changelog.py (mercurial/hg.py)
    File: mercurial/changelog.py (mercurial/hg.py)
    File: mercurial/changelog.py (mercurial/hg.py)
    File: mercurial/changelog.py (mercurial/hg.py)
    File: mercurial/changelog.py (mercurial/hg.py)

What was happening was that in the first call to runtemplate() inside runmap(),
'lm' mapped the keyword (e.g. file_copies) to the appropriate showxxx() method.
On each subsequent call to runtemplate() in that loop however, the keyword was
mapped to a list of the first item's pieces, e.g.:

   'file_copy': ['mercurial/changelog.py', ' (', 'mercurial/hg.py', ')']

Therefore, the dict for the second and any subsequent items were not processed
through the corresponding showxxx() method, and the first item's data was
reused.

The 'extras' keyword regressed in de7e6c489412, and 'file_copies' regressed in
0b241d7a8c62 for other reasons.  The common thread of things fixed by this seems
to be when a list of dicts are passed to the templatekw._hybrid class.

Mercurial has the ability to add new features through the use of
extensions. Extensions may add new commands, add options to
existing commands, change the default behavior of commands, or
implement hooks.

To enable the "foo" extension, either shipped with Mercurial or in the
Python search path, create an entry for it in your configuration file,
like this::

  [extensions]
  foo =

You may also specify the full path to an extension::

  [extensions]
  myfeature = ~/.hgext/myfeature.py

See :hg:`help config` for more information on configuration files.

Extensions are not loaded by default for a variety of reasons:
they can increase startup overhead; they may be meant for advanced
usage only; they may provide potentially dangerous abilities (such
as letting you destroy or modify history); they might not be ready
for prime time; or they may alter some usual behaviors of stock
Mercurial. It is thus up to the user to activate extensions as
needed.

To explicitly disable an extension enabled in a configuration file of
broader scope, prepend its path with !::

  [extensions]
  # disabling extension bar residing in /path/to/extension/bar.py
  bar = !/path/to/extension/bar.py
  # ditto, but no path was supplied for extension baz
  baz = !