Commit graph

16 commits

Author SHA1 Message Date
Jaydeep P Das 09188ed930 userdiff: add builtin diff driver for kotlin language.
The xfuncname pattern finds func/class declarations
in diffs to display as a hunk header. The word_regex
pattern finds individual tokens in Kotlin code to generate
appropriate diffs.

This patch adds xfuncname regex and word_regex for Kotlin
language.

Signed-off-by: Jaydeep P Das <jaydeepjd.8914@gmail.com>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-12 18:15:47 -08:00
Johannes Sixt 386076ec92 userdiff-cpp: back out the digit-separators in numbers
The implementation of digit-separating single-quotes introduced a
note-worthy regression: the change of a character literal with a
digit would splice the digit and the closing single-quote. For
example, the change from 'a' to '2' is now tokenized as
'[-a'-]{+2'+} instead of '[-a-]{+2+}'.

The options to fix the regression are:

- Tighten the regular expression such that the single-quote can only
  occur between digits (that would match the official syntax).

- Remove support for digit separators.

I chose to remove support, because

- I have not seen a lot of code make use of digit separators.

- If code does use digit separators, then the numbers are typically
  long. If a change in one of the segments occurs, it is actually
  better visible if only that segment is highlighted as the word
  that changed instead of the whole long number.

This choice does introduce another minor regression, though, which
is highlighted in the test case: when a change occurs in the second
or later segment of a hexadecimal number where the segment begins
with a digit, but also has letters, the segment is mistaken as
consisting of a number and an identifier. I can live with that.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-25 08:47:44 -07:00
Johannes Sixt c4fdba3383 userdiff-cpp: learn the C++ spaceship operator
Since C++20, the language has a generalized comparison operator <=>.
Teach the cpp driver not to separate it into <= and > tokens.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-10 15:24:21 -07:00
Johannes Sixt 637b80cd6a userdiff-cpp: permit the digit-separating single-quote in numbers
Since C++17, the single-quote can be used as digit separator:

   3.141'592'654
   1'000'000
   0xdead'beaf

Make it known to the word regex of the cpp driver, so that numbers are
not split into separate tokens at the single-quotes.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-10 15:24:21 -07:00
Johannes Sixt bfaaf191a5 userdiff-cpp: prepare test cases with yet unsupported features
We are going to add support for C++'s digit-separating single-quote and
the spaceship operator. By adding the test cases in this separate
commit, the effect on the word highlighting will become more obvious
as the features are implemented and the file cpp/expect is updated.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-10 15:24:21 -07:00
Johannes Sixt 350b87cd65 userdiff-cpp: tighten word regex
Generally, word regex can be written such that they match tokens
liberally and need not model the actual syntax because it can be assumed
that the regex will only be applied to syntactically correct text.

The regex for cpp (C/C++) is too liberal, though. It regards these
sequences as single tokens:

   1+2
   1.5-e+2+f

and the following amalgams as one token:

   .l      as in str.length
   .f      as in str.find
   .e      as in str.erase

Tighten the regex in the following way:

- Accept + and - only in one position in the exponent. + and - are no
  longer regarded as the sign of a number and are treated by the
  catcher-all that is not visible in the driver's regex.

- Accept a leading decimal point only when it is followed by a digit.

For readability, factor hex- and binary numbers into an own term.

As a drive-by, this fixes that floating point numbers such as 12E5
(with upper-case E) were split into two tokens.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 13:04:07 -07:00
Johannes Sixt 3e063de46e t4034: add tests showing problematic cpp tokenizations
The word regex is too loose and matches long streaks of characters
that should actually be separate tokens.  Add these problematic test
cases. Separate the lines with text that will remain identical in the
pre- and post-image so that the diff algorithm will not lump removals
and additions of consecutive lines together. This makes the expected
output easier to read.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 13:04:07 -07:00
Johannes Sixt 1cf93847c1 t4034/cpp: actually test that operator tokens are not split
8d96e7288f (t4034: bulk verify builtin word regex sanity, 2010-12-18)
added many tests with the intent to verify that operators consisting of
more than one symbol are kept together. These are tested by probing a
transition from, e.g., a!=b to x!=y, which results in the word-diff

  [-a-]{+x+}!=[-b-]{+y+}

But that proves only that the letters and operators are separate tokens.
To prove that != is an unseparable token, we have to probe a transition
from, e.g., a=b to a!=b having a word-diff

  a[-=-]{+!=+}b

that proves that the ! is not separate from the =.

In the post-image, add to or remove from operators a character that
turns it into another valid operator.

Change the identifiers used around operators such that the diff
algorithm does not have an incentive to match, e.g., a<b in one spot
in the pre-image with a<b elsewhere in the post-image.

Adjust the expected output to match the new differences. Notice that
there are some undesirable tokenizations around e, ., and -.  This will
be addressed in a later change.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 13:04:07 -07:00
Atharva Raykar a437390310 userdiff: add support for Scheme
Add a diff driver for Scheme-like languages which recognizes top level
and local `define` forms, whether it is a function definition, binding,
syntax definition or a user-defined `define-xyzzy` form.

Also supports R6RS `library` forms, `module` forms along with class and
struct declarations used in Racket (PLT Scheme).

Alternate "def" syntax such as those in Gerbil Scheme are also
supported, like defstruct, defsyntax and so on.

The rationale for picking `define` forms for the hunk headers is because
it is usually the only significant form for defining the structure of
the program, and it is a common pattern for schemers to have local
function definitions to hide their visibility, so it is not only the top
level `define`'s that are of interest. Schemers also extend the language
with macros to provide their own define forms (for example, something
like a `define-test-suite`) which is also captured in the hunk header.

Since it is common practice to extend syntax with variants of a form
like `module+`, `class*` etc, those have been supported as well.

The word regex is a best-effort attempt to conform to R7RS[1] valid
identifiers, symbols and numbers.

[1] https://small.r7rs.org/attachment/r7rs.pdf (section 2.1)

Signed-off-by: Atharva Raykar <raykar.ath@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-08 13:56:09 -07:00
Stephen Boyd 3c81760bc6 userdiff: add a builtin pattern for dts files
The Linux kernel receives many patches to the devicetree files each
release. The hunk header for those patches typically show nothing,
making it difficult to figure out what node is being modified without
applying the patch or opening the file and seeking to the context. Let's
add a builtin 'dts' pattern to git so that users can get better diff
output on dts files when they use the diff=dts driver.

The regex has been constructed based on the spec at devicetree.org[1]
and with some help from Johannes Sixt.

[1] https://github.com/devicetree-org/devicetree-specification/releases/latest

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-08-21 15:09:34 -07:00
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
Adrian Johnson 39a87a29ce userdiff: update Ada patterns
- Allow extra space in "is new" and "is separate"
- Fix bug in word regex for numbers

Signed-off-by: Adrian Johnson <ajohnson@redneon.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-02-05 10:45:51 -08:00
Adrian Johnson e90d065e64 Add userdiff patterns for Ada
Add Ada xfuncname and wordRegex patterns to the list of builtin
patterns.

Signed-off-by: Adrian Johnson <ajohnson@redneon.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-16 21:54:47 -07:00
Gustaf Hendeby 53b10a1405 Add built-in diff patterns for MATLAB code
MATLAB is often used in industry and academia for scientific
computations motivating it being included as a built-in pattern.

Signed-off-by: Gustaf Hendeby <hendeby@isy.liu.se>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-11-15 16:11:52 -08:00
Junio C Hamano 5269edf170 t4034 (diff --word-diff): add a minimum Perl drier test vector
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-01-18 09:44:22 -08:00
Thomas Rast 8d96e7288f t4034: bulk verify builtin word regex sanity
The builtin word regexes should be tested with some simple examples
against simple issues.  Do this in bulk.

Mainly due to a lack of language knowledge and inspiration, most of
the test cases (cpp, csharp, java, objc, pascal, php, python, ruby)
are directly based off a C operator precedence table to verify that
all operators are split correctly.  This means that they are probably
incomplete or inaccurate except for 'cpp' itself.

Still, they are good enough to already have uncovered a typo in the
python and ruby patterns.

'fortran' is based on my anecdotal knowledge of the DO10I parsing
rules, and thus probably useless.  The rest (bibtex, html, tex) are an
ad-hoc test of what I consider important splits in those languages.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-01-18 08:51:58 -08:00