view mercurial/helptext/filesets.txt @ 49803:55d45d0de4e7

typing: add type hints to pycompat.bytestr

The problem with leaving pytype to its own devices here was that for functions
that returned a bytestr, pytype inferred `Union[bytes, int]`.  It now accepts
that it can be treated as plain bytes.

I wasn't able to figure out the arg type for `__getitem__`- `SupportsIndex`
(which PyCharm indicated is how the superclass function is typed) got flagged:

    File "/mnt/c/Users/Matt/hg/mercurial/pycompat.py", line 236, in __getitem__:
        unsupported operand type(s) for item retrieval: bytestr and SupportsIndex [unsupported-operands]
      Function __getitem__ on bytestr expects int

But some caller got flagged when I marked it as `int`.

There's some minor spillover problems elsewhere- pytype doesn't seem to
recognize that `bytes.startswith()` can optionally take a 3rd and 4th arg, so
those few places have the warning disabled.  It also flags where the tar API is
being abused, but that would be a tricky refactor (and would require typing
extensions until py3.7 is dropped), so disable those too.

Mercurial supports a functional language for selecting a set of
files.

Like other file patterns, this pattern type is indicated by a prefix,
'set:'. The language supports a number of predicates which are joined
by infix operators. Parenthesis can be used for grouping.

Identifiers such as filenames or patterns must be quoted with single
or double quotes if they contain characters outside of
``[.*{}[]?/\_a-zA-Z0-9\x80-\xff]`` or if they match one of the
predefined predicates. This generally applies to file patterns other
than globs and arguments for predicates. Pattern prefixes such as
``path:`` may be specified without quoting.

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'...'``.

See also :hg:`help patterns`.

Operators
=========

There is a single prefix operator:

``not x``
  Files not in x. Short form is ``! x``.

These are the supported infix operators:

``x and y``
  The intersection of files in x and y. Short form is ``x & y``.

``x or y``
  The union of files in x and y. There are two alternative short
  forms: ``x | y`` and ``x + y``.

``x - y``
  Files in x but not in y.

Predicates
==========

The following predicates are supported:

.. predicatesmarker

Examples
========

Some sample queries:

- Show status of files that appear to be binary in the working directory::

    hg status -A "set:binary()"

- Forget files that are in .hgignore but are already tracked::

    hg forget "set:hgignore() and not ignored()"

- Find text files that contain a string::

    hg files "set:grep(magic) and not binary()"

- Find C files in a non-standard encoding::

    hg files "set:**.c and not encoding('UTF-8')"

- Revert copies of large binary files::

    hg revert "set:copied() and binary() and size('>1M')"

- Revert files that were added to the working directory::

    hg revert "set:revs('wdir()', added())"

- Remove files listed in foo.lst that contain the letter a or b::

    hg remove "set: listfile:foo.lst and (**a* or **b*)"