hgweb: side-by-side comparison functionality
Adds new web command to the core, ``comparison``, which enables colorful
side-by-side change display, which for some might be much easier to work with
than the standard line diff output. The idea how to implement comes from the
SonicHq extension.
The web interface gets a new link to call the comparison functionality. It lets
users configure the amount of context lines around change blocks, or to show
full files - check help (also in this changeset) for details and defaults. The
setting in hgrc can be overridden by adding ``context=<value>`` to the request
query string. The comparison creates addressable lines, so as to enable sharing
links to specific lines, just as standard diff does.
Incorporates updates to all web related styles.
Known limitations:
* the column diff is done against the first parent, just as the standard diff
* this change allows examining diffs for single files only (as I am not sure if
examining the whole changeset in this way would be helpful)
* syntax highlighting of the output changes is not performed (enabling the
highlight extension has no influence on it)
Mercurial supports a functional language for selecting a set of
revisions.
The language supports a number of predicates which are joined by infix
operators. Parenthesis can be used for grouping.
Identifiers such as branch names may need quoting with single or
double quotes if they contain characters like ``-`` or if they match
one of the predefined predicates.
Special characters can be used in quoted identifiers by escaping them,
e.g., ``\n`` is interpreted as a newline. To prevent them from being
interpreted, strings can be prefixed with ``r``, e.g. ``r'...'``.
There is a single prefix operator:
``not x``
Changesets not in x. Short form is ``! x``.
These are the supported infix operators:
``x::y``
A DAG range, meaning all changesets that are descendants of x and
ancestors of y, including x and y themselves. If the first endpoint
is left out, this is equivalent to ``ancestors(y)``, if the second
is left out it is equivalent to ``descendants(x)``.
An alternative syntax is ``x..y``.
``x:y``
All changesets with revision numbers between x and y, both
inclusive. Either endpoint can be left out, they default to 0 and
tip.
``x and y``
The intersection of changesets in x and y. Short form is ``x & y``.
``x or y``
The union of changesets in x and y. There are two alternative short
forms: ``x | y`` and ``x + y``.
``x - y``
Changesets in x but not in y.
``x^n``
The nth parent of x, n == 0, 1, or 2.
For n == 0, x; for n == 1, the first parent of each changeset in x;
for n == 2, the second parent of changeset in x.
``x~n``
The nth first ancestor of x; ``x~0`` is x; ``x~3`` is ``x^^^``.
There is a single postfix operator:
``x^``
Equivalent to ``x^1``, the first parent of each changeset in x.
The following predicates are supported:
.. predicatesmarker
New predicates (known as "aliases") can be defined, using any combination of
existing predicates or other aliases. An alias definition looks like::
<alias> = <definition>
in the ``revsetalias`` section of a Mercurial configuration file. Arguments
of the form `$1`, `$2`, etc. are substituted from the alias into the
definition.
For example,
::
[revsetalias]
h = heads()
d($1) = sort($1, date)
rs($1, $2) = reverse(sort($1, $2))
defines three aliases, ``h``, ``d``, and ``rs``. ``rs(0:tip, author)`` is
exactly equivalent to ``reverse(sort(0:tip, author))``.
Command line equivalents for :hg:`log`::
-f -> ::.
-d x -> date(x)
-k x -> keyword(x)
-m -> merge()
-u x -> user(x)
-b x -> branch(x)
-P x -> !::x
-l x -> limit(expr, x)
Some sample queries:
- Changesets on the default branch::
hg log -r "branch(default)"
- Changesets on the default branch since tag 1.5 (excluding merges)::
hg log -r "branch(default) and 1.5:: and not merge()"
- Open branch heads::
hg log -r "head() and not closed()"
- Changesets between tags 1.3 and 1.5 mentioning "bug" that affect
``hgext/*``::
hg log -r "1.3::1.5 and keyword(bug) and file('hgext/*')"
- Changesets committed in May 2008, sorted by user::
hg log -r "sort(date('May 2008'), user)"
- Changesets mentioning "bug" or "issue" that are not in a tagged
release::
hg log -r "(keyword(bug) or keyword(issue)) and not ancestors(tagged())"