Commit Graph

10 Commits

Author SHA1 Message Date
Alban Gruin
1dbf0c0ad6 userdiff: add built-in pattern for golang
This adds xfuncname and word_regex patterns for golang, a quite
popular programming language. It also includes test cases for the
xfuncname regex (t4018) and updated documentation.

The xfuncname regex finds functions, structs and interfaces.  Although
the Go language prohibits the opening brace from being on its own
line, the regex does not makes it mandatory, to be able to match
`func` statements like this:

    func foo(bar int,
    	baz int) {
    }

This is covered by the test case t4018/golang-long-func.

The word_regex pattern finds identifiers, integers, floats, complex
numbers and operators, according to the go specification.

Signed-off-by: Alban Gruin <alban.gruin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-03-01 13:36:49 -08:00
William Duclot
0719f3eecd userdiff: add built-in pattern for CSS
CSS is widely used, motivating it being included as a built-in pattern.

It must be noted that the word_regex for CSS (i.e. the regex defining
what is a word in the language) does not consider '.' and '#' characters
(in CSS selectors) to be part of the word. This behavior is documented
by the test t/t4018/css-rule.
The logic behind this behavior is the following: identifiers in CSS
selectors are identifiers in a HTML/XML document. Therefore, the '.'/'#'
character are not part of the identifier, but an indicator of the nature
of the identifier in HTML/XML (class or id). Diffing ".class1" and
".class2" must show that the class name is changed, but we still are
selecting a class.

Logic behind the "pattern" regex is:
    1. reject lines ending with a colon/semicolon (properties)
    2. if a line begins with a name in column 1, pick the whole line

Credits to Johannes Sixt (j6t@kdbg.org) for the pattern regex and most
of the tests.

Signed-off-by: William Duclot <william.duclot@ensimag.grenoble-inp.fr>
Signed-off-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Reviewed-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-03 14:45:56 -07:00
Zoë Blade
69f9c87d46 userdiff: add support for Fountain documents
Add support for Fountain, a plain text screenplay format.  Git
facilitates not just programming specifically, but creative writing
in general, so it makes sense to also support other plain text
documents besides source code.

In the structure of a screenplay specifically, scenes are roughly
analogous to functions, in the sense that it makes your job easier
if you can see which ones were changed in a given range of patches.

More information about the Fountain format can be found on its
official website, at http://fountain.io .

Signed-off-by: Zoë Blade <zoe@bytenoise.co.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-07-23 14:44:51 -07:00
Johannes Sixt
8a2e8da367 userdiff: have 'cpp' hunk header pattern catch more C++ anchor points
The hunk header pattern 'cpp' is intended for C and C++ source code, but
it is actually not particularly useful for the latter, and even misses
some use-cases for the former.

The parts of the pattern have the following flaws:

- The first part matches an identifier followed immediately by a colon
  and arbitrary text and is intended to reject goto labels and C++
  access specifiers (public, private, protected). But this pattern also
  rejects C++ constructs, which look like this:

    MyClass::MyClass()
    MyClass::~MyClass()
    MyClass::Item MyClass::Find(...

- The second part matches an identifier followed by a list of qualified
  names (i.e. identifiers separated by the C++ scope operator '::')
  separated by space or '*' followed by an opening parenthesis (with
  space between the tokens). It matches function declarations like

    struct item* get_head(...
    int Outer::Inner::Func(...

  Since the pattern requires at least two identifiers, GNU-style
  function definitions are ignored:

    void
    func(...

  Moreover, since the pattern does not allow punctuation other than '*',
  the following C++ constructs are not recognized:

  . template definitions:
      template<class T> int func(T arg)

  . functions returning references:
      const string& get_message()

  . functions returning templated types:
      vector<int> foo()

  . operator definitions:
      Value operator+(Value l, Value r)

- The third part of the pattern finally matches compound definitions.
  But it forgets about unions and namespaces, and also skips single-line
  definitions

    struct random_iterator_tag {};

  because no semicolon can occur on the line.

Change the first pattern to require a colon at the end of the line
(except for trailing space and comments), so that it does not reject
constructor or destructor definitions.

Notice that all interesting anchor points begin with an identifier or
keyword. But since there is a large variety of syntactical constructs
after the first "word", the simplest is to require only this word and
accept everything else. Therefore, this boils down to a line that begins
with a letter or underscore (optionally preceded by the C++ scope
operator '::' to accept functions returning a type anchored at the
global namespace). Replace the second and third part by a single pattern
that picks such a line.

This has the following desirable consequence:

- All constructs mentioned above are recognized.

and the following likely desirable consequences:

- Definitions of global variables and typedefs are recognized:

    int num_entries = 0;
    extern const char* help_text;
    typedef basic_string<wchar_t> wstring;

- Commonly used marco-ized boilerplate code is recognized:

    BEGIN_MESSAGE_MAP(CCanvas,CWnd)
    Q_DECLARE_METATYPE(MyStruct)
    PATTERNS("tex",...)

  (The last one is from this very patch.)

but also the following possibly undesirable consequence:

- When a label is not on a line by itself (except for a comment) it is
  no longer rejected, but can appear as a hunk header if it occurs at
  the beginning of a line:

    next:;

IMO, the benefits of the change outweigh the (possible) regressions by a
large margin.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-21 15:03:32 -07:00
Johannes Sixt
9cc444f057 t4018: test cases showing that the cpp pattern misses many anchor points
Most of the tests show C++ code, but there is also a union definition and
a GNU style function definition that are not recognized.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-21 15:03:31 -07:00
Johannes Sixt
02907a08cc t4018: test cases for the built-in cpp pattern
A later patch changes the built-in cpp pattern. These test cases
demonstrate aspects of the pattern that we do not want to change.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-21 15:03:29 -07:00
Johannes Sixt
f1b75fbaf1 t4018: convert custom pattern test to the new infrastructure
For the test case "matches to end of line", extend the pattern by a few
wildcards so that the pattern captures the "RIGHT" token, which is needed
for verification, without mentioning it in the pattern.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-21 15:02:57 -07:00
Johannes Sixt
dd4dc5c574 t4018: convert java pattern test to the new infrastructure
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-21 15:02:36 -07:00
Johannes Sixt
2d08413ba1 t4018: convert perl pattern tests to the new infrastructure
There is one subtlety: The old test case 'perl pattern gets full line of
POD header' does not have its own new test case, but the feature is
tested nevertheless by placing the RIGHT tag at the end of the expected
hunk header in t4018/perl-skip-sub-in-pod.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-21 15:02:19 -07:00
Johannes Sixt
bfa7d01413 t4018: an infrastructure to test hunk headers
Add an infrastructure that simplifies adding new tests of the hunk
header regular expressions.

To add new tests, a file with the syntax to test can be dropped in the
directory t4018. The README file explains how a test file must contain;
the README itself tests the default behavior.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-21 15:00:51 -07:00