copies: avoid instancing more changectx to access parent revisions
We just need to know the revision numbers of the parents, creating full context
is needlessly expensive.
This provide a small, but noticeable performance boost.
revision: large amount; added files: large amount; rename small amount;
c3b14617fbd7 9ba6ab77fd29
before: ! wall 2.885636 comb 2.900000 user 2.870000 sys 0.030000 (median of 10)
after: ! wall 2.702270 comb 2.710000 user 2.690000 sys 0.020000 (median of 10)
revision: large amount; added files: small amount; rename small amount;
c3b14617fbd7 f650a9b140d2
before: ! wall 4.298271 comb 4.290000 user 4.240000 sys 0.050000 (median of 10)
after: ! wall 3.976610 comb 3.970000 user 3.920000 sys 0.050000 (median of 10)
revision: large amount; added files: large amount; rename large amount;
08ea3258278e d9fa043f30c0
before: ! wall 0.773397 comb 0.770000 user 0.770000 sys 0.000000 (median of 11)
after: ! wall 0.701634 comb 0.700000 user 0.700000 sys 0.000000 (median of 13)
revision: small amount; added files: large amount; rename large amount;
df6f7a526b60 a83dc6a2d56f
before: ! wall 0.013585 comb 0.010000 user 0.010000 sys 0.000000 (median of 217)
after: ! wall 0.013550 comb 0.010000 user 0.010000 sys 0.000000 (median of 218)
revision: small amount; added files: large amount; rename small amount;
4aa4e1f8e19a 169138063d63
before: ! wall 0.003202 comb 0.000000 user 0.000000 sys 0.000000 (median of 929)
after: ! wall 0.002993 comb 0.010000 user 0.010000 sys 0.000000 (median of 992)
revision: small amount; added files: small amount; rename small amount;
4bc173b045a6 964879152e2e
before: ! wall 0.000077 comb 0.000000 user 0.000000 sys 0.000000 (median of 12060)
after: ! wall 0.000072 comb 0.000000 user 0.000000 sys 0.000000 (median of 12804)
revision: medium amount; added files: large amount; rename medium amount;
c95f1ced15f2 2c68e87c3efe
before: ! wall 0.510614 comb 0.500000 user 0.500000 sys 0.000000 (median of 18)
after: ! wall 0.473681 comb 0.470000 user 0.470000 sys 0.000000 (median of 20)
revision: medium amount; added files: medium amount; rename small amount;
d343da0c55a8 d7746d32bf9d
before: ! wall 0.126552 comb 0.130000 user 0.130000 sys 0.000000 (median of 77)
after: ! wall 0.115240 comb 0.110000 user 0.110000 sys 0.000000 (median of 85)
Differential Revision: https://phab.mercurial-scm.org/D7122
Mercurial allows you to customize output of commands through
templates. You can either pass in a template or select an existing
template-style from the command line, via the --template option.
You can customize output for any "log-like" command: log,
outgoing, incoming, tip, parents, and heads.
Some built-in styles are packaged with Mercurial. These can be listed
with :hg:`log --template list`. Example usage::
$ hg log -r1.0::1.1 --template changelog
A template is a piece of text, with markup to invoke variable
expansion::
$ hg log -r1 --template "{node}\n"
b56ce7b07c52de7d5fd79fb89701ea538af65746
Keywords
========
Strings in curly braces are called keywords. The availability of
keywords depends on the exact context of the templater. These
keywords are usually available for templating a log-like command:
.. keywordsmarker
The "date" keyword does not produce human-readable output. If you
want to use a date in your output, you can use a filter to process
it. Filters are functions which return a string based on the input
variable. Be sure to use the stringify filter first when you're
applying a string-input filter to a list-like input variable.
You can also use a chain of filters to get the desired output::
$ hg tip --template "{date|isodate}\n"
2008-08-21 18:22 +0000
Filters
=======
List of filters:
.. filtersmarker
Note that a filter is nothing more than a function call, i.e.
``expr|filter`` is equivalent to ``filter(expr)``.
Functions
=========
In addition to filters, there are some basic built-in functions:
.. functionsmarker
Operators
=========
We provide a limited set of infix arithmetic operations on integers::
+ for addition
- for subtraction
* for multiplication
/ for floor division (division rounded to integer nearest -infinity)
Division fulfills the law x = x / y + mod(x, y).
Also, for any expression that returns a list, there is a list operator::
expr % "{template}"
As seen in the above example, ``{template}`` is interpreted as a template.
To prevent it from being interpreted, you can use an escape character ``\{``
or a raw string prefix, ``r'...'``.
The dot operator can be used as a shorthand for accessing a sub item:
- ``expr.member`` is roughly equivalent to ``expr % '{member}'`` if ``expr``
returns a non-list/dict. The returned value is not stringified.
- ``dict.key`` is identical to ``get(dict, 'key')``.
Aliases
=======
New keywords and functions can be defined in the ``templatealias`` section of
a Mercurial configuration file::
<alias> = <definition>
Arguments of the form `a1`, `a2`, etc. are substituted from the alias into
the definition.
For example,
::
[templatealias]
r = rev
rn = "{r}:{node|short}"
leftpad(s, w) = pad(s, w, ' ', True)
defines two symbol aliases, ``r`` and ``rn``, and a function alias
``leftpad()``.
It's also possible to specify complete template strings, using the
``templates`` section. The syntax used is the general template string syntax.
For example,
::
[templates]
nodedate = "{node|short}: {date(date, "%Y-%m-%d")}\n"
defines a template, ``nodedate``, which can be called like::
$ hg log -r . -Tnodedate
A template defined in ``templates`` section can also be referenced from
another template::
$ hg log -r . -T "{rev} {nodedate}"
but be aware that the keywords cannot be overridden by templates. For example,
a template defined as ``templates.rev`` cannot be referenced as ``{rev}``.
A template defined in ``templates`` section may have sub templates which
are inserted before/after/between items::
[templates]
myjson = ' {dict(rev, node|short)|json}'
myjson:docheader = '\{\n'
myjson:docfooter = '\n}\n'
myjson:separator = ',\n'
Examples
========
Some sample command line templates:
- Format lists, e.g. files::
$ hg log -r 0 --template "files:\n{files % ' {file}\n'}"
- Join the list of files with a ", "::
$ hg log -r 0 --template "files: {join(files, ', ')}\n"
- Join the list of files ending with ".py" with a ", "::
$ hg log -r 0 --template "pythonfiles: {join(files('**.py'), ', ')}\n"
- Separate non-empty arguments by a " "::
$ hg log -r 0 --template "{separate(' ', node, bookmarks, tags}\n"
- Modify each line of a commit description::
$ hg log --template "{splitlines(desc) % '**** {line}\n'}"
- Format date::
$ hg log -r 0 --template "{date(date, '%Y')}\n"
- Display date in UTC::
$ hg log -r 0 --template "{localdate(date, 'UTC')|date}\n"
- Output the description set to a fill-width of 30::
$ hg log -r 0 --template "{fill(desc, 30)}"
- Use a conditional to test for the default branch::
$ hg log -r 0 --template "{ifeq(branch, 'default', 'on the main branch',
'on branch {branch}')}\n"
- Append a newline if not empty::
$ hg tip --template "{if(author, '{author}\n')}"
- Label the output for use with the color extension::
$ hg log -r 0 --template "{label('changeset.{phase}', node|short)}\n"
- Invert the firstline filter, i.e. everything but the first line::
$ hg log -r 0 --template "{sub(r'^.*\n?\n?', '', desc)}\n"
- Display the contents of the 'extra' field, one per line::
$ hg log -r 0 --template "{join(extras, '\n')}\n"
- Mark the active bookmark with '*'::
$ hg log --template "{bookmarks % '{bookmark}{ifeq(bookmark, active, '*')} '}\n"
- Find the previous release candidate tag, the distance and changes since the tag::
$ hg log -r . --template "{latesttag('re:^.*-rc$') % '{tag}, {changes}, {distance}'}\n"
- Mark the working copy parent with '@'::
$ hg log --template "{ifcontains(rev, revset('.'), '@')}\n"
- Show details of parent revisions::
$ hg log --template "{revset('parents(%d)', rev) % '{desc|firstline}\n'}"
- Show only commit descriptions that start with "template"::
$ hg log --template "{startswith('template', firstline(desc))}\n"
- Print the first word of each line of a commit message::
$ hg log --template "{word(0, desc)}\n"