git/userdiff.c
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

456 lines
15 KiB
C

#include "cache.h"
#include "config.h"
#include "userdiff.h"
#include "attr.h"
static struct userdiff_driver *drivers;
static int ndrivers;
static int drivers_alloc;
#define PATTERNS(name, pattern, word_regex) \
{ name, NULL, -1, { pattern, REG_EXTENDED }, \
word_regex "|[^[:space:]]|[\xc0-\xff][\x80-\xbf]+" }
#define IPATTERN(name, pattern, word_regex) \
{ name, NULL, -1, { pattern, REG_EXTENDED | REG_ICASE }, \
word_regex "|[^[:space:]]|[\xc0-\xff][\x80-\xbf]+" }
/*
* Built-in drivers for various languages, sorted by their names
* (except that the "default" is left at the end).
*
* When writing or updating patterns, assume that the contents these
* patterns are applied to are syntactically correct. The patterns
* can be simple without implementing all syntactical corner cases, as
* long as they are sufficiently permissive.
*/
static struct userdiff_driver builtin_drivers[] = {
IPATTERN("ada",
"!^(.*[ \t])?(is[ \t]+new|renames|is[ \t]+separate)([ \t].*)?$\n"
"!^[ \t]*with[ \t].*$\n"
"^[ \t]*((procedure|function)[ \t]+.*)$\n"
"^[ \t]*((package|protected|task)[ \t]+.*)$",
/* -- */
"[a-zA-Z][a-zA-Z0-9_]*"
"|[-+]?[0-9][0-9#_.aAbBcCdDeEfF]*([eE][+-]?[0-9_]+)?"
"|=>|\\.\\.|\\*\\*|:=|/=|>=|<=|<<|>>|<>"),
PATTERNS("bash",
/* Optional leading indentation */
"^[ \t]*"
/* Start of captured text */
"("
"("
/* POSIX identifier with mandatory parentheses */
"[a-zA-Z_][a-zA-Z0-9_]*[ \t]*\\([ \t]*\\))"
"|"
/* Bashism identifier with optional parentheses */
"(function[ \t]+[a-zA-Z_][a-zA-Z0-9_]*(([ \t]*\\([ \t]*\\))|([ \t]+))"
")"
/* Optional whitespace */
"[ \t]*"
/* Compound command starting with `{`, `(`, `((` or `[[` */
"(\\{|\\(\\(?|\\[\\[)"
/* End of captured text */
")",
/* -- */
/* Characters not in the default $IFS value */
"[^ \t]+"),
PATTERNS("bibtex",
"(@[a-zA-Z]{1,}[ \t]*\\{{0,1}[ \t]*[^ \t\"@',\\#}{~%]*).*$",
/* -- */
"[={}\"]|[^={}\" \t]+"),
PATTERNS("cpp",
/* Jump targets or access declarations */
"!^[ \t]*[A-Za-z_][A-Za-z_0-9]*:[[:space:]]*($|/[/*])\n"
/* functions/methods, variables, and compounds at top level */
"^((::[[:space:]]*)?[A-Za-z_].*)$",
/* -- */
/* identifiers and keywords */
"[a-zA-Z_][a-zA-Z0-9_]*"
/* decimal and octal integers as well as floatingpoint numbers */
"|[0-9][0-9.]*([Ee][-+]?[0-9]+)?[fFlLuU]*"
/* hexadecimal and binary integers */
"|0[xXbB][0-9a-fA-F]+[lLuU]*"
/* floatingpoint numbers that begin with a decimal point */
"|\\.[0-9][0-9]*([Ee][-+]?[0-9]+)?[fFlL]?"
"|[-+*/<>%&^|=!]=|--|\\+\\+|<<=?|>>=?|&&|\\|\\||::|->\\*?|\\.\\*|<=>"),
PATTERNS("csharp",
/* Keywords */
"!^[ \t]*(do|while|for|if|else|instanceof|new|return|switch|case|throw|catch|using)\n"
/* Methods and constructors */
"^[ \t]*(((static|public|internal|private|protected|new|virtual|sealed|override|unsafe|async)[ \t]+)*[][<>@.~_[:alnum:]]+[ \t]+[<>@._[:alnum:]]+[ \t]*\\(.*\\))[ \t]*$\n"
/* Properties */
"^[ \t]*(((static|public|internal|private|protected|new|virtual|sealed|override|unsafe)[ \t]+)*[][<>@.~_[:alnum:]]+[ \t]+[@._[:alnum:]]+)[ \t]*$\n"
/* Type definitions */
"^[ \t]*(((static|public|internal|private|protected|new|unsafe|sealed|abstract|partial)[ \t]+)*(class|enum|interface|struct|record)[ \t]+.*)$\n"
/* Namespace */
"^[ \t]*(namespace[ \t]+.*)$",
/* -- */
"[a-zA-Z_][a-zA-Z0-9_]*"
"|[-+0-9.e]+[fFlL]?|0[xXbB]?[0-9a-fA-F]+[lL]?"
"|[-+*/<>%&^|=!]=|--|\\+\\+|<<=?|>>=?|&&|\\|\\||::|->"),
IPATTERN("css",
"![:;][[:space:]]*$\n"
"^[:[@.#]?[_a-z0-9].*$",
/* -- */
/*
* This regex comes from W3C CSS specs. Should theoretically also
* allow ISO 10646 characters U+00A0 and higher,
* but they are not handled in this regex.
*/
"-?[_a-zA-Z][-_a-zA-Z0-9]*" /* identifiers */
"|-?[0-9]+|\\#[0-9a-fA-F]+" /* numbers */
),
PATTERNS("dts",
"!;\n"
"!=\n"
/* lines beginning with a word optionally preceded by '&' or the root */
"^[ \t]*((/[ \t]*\\{|&?[a-zA-Z_]).*)",
/* -- */
/* Property names and math operators */
"[a-zA-Z0-9,._+?#-]+"
"|[-+*/%&^|!~]|>>|<<|&&|\\|\\|"),
PATTERNS("elixir",
"^[ \t]*((def(macro|module|impl|protocol|p)?|test)[ \t].*)$",
/* -- */
/* Atoms, names, and module attributes */
"[@:]?[a-zA-Z0-9@_?!]+"
/* Numbers with specific base */
"|[-+]?0[xob][0-9a-fA-F]+"
/* Numbers */
"|[-+]?[0-9][0-9_.]*([eE][-+]?[0-9_]+)?"
/* Operators and atoms that represent them */
"|:?(\\+\\+|--|\\.\\.|~~~|<>|\\^\\^\\^|<?\\|>|<<<?|>?>>|<<?~|~>?>|<~>|<=|>=|===?|!==?|=~|&&&?|\\|\\|\\|?|=>|<-|\\\\\\\\|->)"
/* Not real operators, but should be grouped */
"|:?%[A-Za-z0-9_.]\\{\\}?"),
IPATTERN("fortran",
/* Don't match comment lines */
"!^([C*]|[ \t]*!)\n"
/* Don't match 'module procedure' lines */
"!^[ \t]*MODULE[ \t]+PROCEDURE[ \t]\n"
/* Program, module, block data */
"^[ \t]*((END[ \t]+)?(PROGRAM|MODULE|BLOCK[ \t]+DATA"
/* Subroutines and functions */
"|([^!'\" \t]+[ \t]+)*(SUBROUTINE|FUNCTION))[ \t]+[A-Z].*)$",
/* -- */
"[a-zA-Z][a-zA-Z0-9_]*"
"|\\.([Ee][Qq]|[Nn][Ee]|[Gg][TtEe]|[Ll][TtEe]|[Tt][Rr][Uu][Ee]|[Ff][Aa][Ll][Ss][Ee]|[Aa][Nn][Dd]|[Oo][Rr]|[Nn]?[Ee][Qq][Vv]|[Nn][Oo][Tt])\\."
/* numbers and format statements like 2E14.4, or ES12.6, 9X.
* Don't worry about format statements without leading digits since
* they would have been matched above as a variable anyway. */
"|[-+]?[0-9.]+([AaIiDdEeFfLlTtXx][Ss]?[-+]?[0-9.]*)?(_[a-zA-Z0-9][a-zA-Z0-9_]*)?"
"|//|\\*\\*|::|[/<>=]="),
IPATTERN("fountain",
"^((\\.[^.]|(int|ext|est|int\\.?/ext|i/e)[. ]).*)$",
/* -- */
"[^ \t-]+"),
PATTERNS("golang",
/* Functions */
"^[ \t]*(func[ \t]*.*(\\{[ \t]*)?)\n"
/* Structs and interfaces */
"^[ \t]*(type[ \t].*(struct|interface)[ \t]*(\\{[ \t]*)?)",
/* -- */
"[a-zA-Z_][a-zA-Z0-9_]*"
"|[-+0-9.eE]+i?|0[xX]?[0-9a-fA-F]+i?"
"|[-+*/<>%&^|=!:]=|--|\\+\\+|<<=?|>>=?|&\\^=?|&&|\\|\\||<-|\\.{3}"),
PATTERNS("html",
"^[ \t]*(<[Hh][1-6]([ \t].*)?>.*)$",
/* -- */
"[^<>= \t]+"),
PATTERNS("java",
"!^[ \t]*(catch|do|for|if|instanceof|new|return|switch|throw|while)\n"
/* Class, enum, and interface declarations */
"^[ \t]*(([a-z]+[ \t]+)*(class|enum|interface)[ \t]+[A-Za-z][A-Za-z0-9_$]*[ \t]+.*)$\n"
/* Method definitions; note that constructor signatures are not */
/* matched because they are indistinguishable from method calls. */
"^[ \t]*(([A-Za-z_<>&][][?&<>.,A-Za-z_0-9]*[ \t]+)+[A-Za-z_][A-Za-z_0-9]*[ \t]*\\([^;]*)$",
/* -- */
"[a-zA-Z_][a-zA-Z0-9_]*"
"|[-+0-9.e]+[fFlL]?|0[xXbB]?[0-9a-fA-F]+[lL]?"
"|[-+*/<>%&^|=!]="
"|--|\\+\\+|<<=?|>>>?=?|&&|\\|\\|"),
PATTERNS("markdown",
"^ {0,3}#{1,6}[ \t].*",
/* -- */
"[^<>= \t]+"),
PATTERNS("matlab",
/*
* Octave pattern is mostly the same as matlab, except that '%%%' and
* '##' can also be used to begin code sections, in addition to '%%'
* that is understood by both.
*/
"^[[:space:]]*((classdef|function)[[:space:]].*)$|^(%%%?|##)[[:space:]].*$",
/* -- */
"[a-zA-Z_][a-zA-Z0-9_]*|[-+0-9.e]+|[=~<>]=|\\.[*/\\^']|\\|\\||&&"),
PATTERNS("objc",
/* Negate C statements that can look like functions */
"!^[ \t]*(do|for|if|else|return|switch|while)\n"
/* Objective-C methods */
"^[ \t]*([-+][ \t]*\\([ \t]*[A-Za-z_][A-Za-z_0-9* \t]*\\)[ \t]*[A-Za-z_].*)$\n"
/* C functions */
"^[ \t]*(([A-Za-z_][A-Za-z_0-9]*[ \t]+)+[A-Za-z_][A-Za-z_0-9]*[ \t]*\\([^;]*)$\n"
/* Objective-C class/protocol definitions */
"^(@(implementation|interface|protocol)[ \t].*)$",
/* -- */
"[a-zA-Z_][a-zA-Z0-9_]*"
"|[-+0-9.e]+[fFlL]?|0[xXbB]?[0-9a-fA-F]+[lL]?"
"|[-+*/<>%&^|=!]=|--|\\+\\+|<<=?|>>=?|&&|\\|\\||::|->"),
PATTERNS("pascal",
"^(((class[ \t]+)?(procedure|function)|constructor|destructor|interface"
"|implementation|initialization|finalization)[ \t]*.*)$\n"
"^(.*=[ \t]*(class|record).*)$",
/* -- */
"[a-zA-Z_][a-zA-Z0-9_]*"
"|[-+0-9.e]+|0[xXbB]?[0-9a-fA-F]+"
"|<>|<=|>=|:=|\\.\\."),
PATTERNS("perl",
"^package .*\n"
"^sub [[:alnum:]_':]+[ \t]*"
"(\\([^)]*\\)[ \t]*)?" /* prototype */
/*
* Attributes. A regex can't count nested parentheses,
* so just slurp up whatever we see, taking care not
* to accept lines like "sub foo; # defined elsewhere".
*
* An attribute could contain a semicolon, but at that
* point it seems reasonable enough to give up.
*/
"(:[^;#]*)?"
"(\\{[ \t]*)?" /* brace can come here or on the next line */
"(#.*)?$\n" /* comment */
"^(BEGIN|END|INIT|CHECK|UNITCHECK|AUTOLOAD|DESTROY)[ \t]*"
"(\\{[ \t]*)?" /* brace can come here or on the next line */
"(#.*)?$\n"
"^=head[0-9] .*", /* POD */
/* -- */
"[[:alpha:]_'][[:alnum:]_']*"
"|0[xb]?[0-9a-fA-F_]*"
/* taking care not to interpret 3..5 as (3.)(.5) */
"|[0-9a-fA-F_]+(\\.[0-9a-fA-F_]+)?([eE][-+]?[0-9_]+)?"
"|=>|-[rwxoRWXOezsfdlpSugkbctTBMAC>]|~~|::"
"|&&=|\\|\\|=|//=|\\*\\*="
"|&&|\\|\\||//|\\+\\+|--|\\*\\*|\\.\\.\\.?"
"|[-+*/%.^&<>=!|]="
"|=~|!~"
"|<<|<>|<=>|>>"),
PATTERNS("php",
"^[\t ]*(((public|protected|private|static|abstract|final)[\t ]+)*function.*)$\n"
"^[\t ]*((((final|abstract)[\t ]+)?class|enum|interface|trait).*)$",
/* -- */
"[a-zA-Z_][a-zA-Z0-9_]*"
"|[-+0-9.e]+|0[xXbB]?[0-9a-fA-F]+"
"|[-+*/<>%&^|=!.]=|--|\\+\\+|<<=?|>>=?|===|&&|\\|\\||::|->"),
PATTERNS("python",
"^[ \t]*((class|(async[ \t]+)?def)[ \t].*)$",
/* -- */
"[a-zA-Z_][a-zA-Z0-9_]*"
"|[-+0-9.e]+[jJlL]?|0[xX]?[0-9a-fA-F]+[lL]?"
"|[-+*/<>%&^|=!]=|//=?|<<=?|>>=?|\\*\\*=?"),
/* -- */
PATTERNS("ruby",
"^[ \t]*((class|module|def)[ \t].*)$",
/* -- */
"(@|@@|\\$)?[a-zA-Z_][a-zA-Z0-9_]*"
"|[-+0-9.e]+|0[xXbB]?[0-9a-fA-F]+|\\?(\\\\C-)?(\\\\M-)?."
"|//=?|[-+*/<>%&^|=!]=|<<=?|>>=?|===|\\.{1,3}|::|[!=]~"),
PATTERNS("rust",
"^[\t ]*((pub(\\([^\\)]+\\))?[\t ]+)?((async|const|unsafe|extern([\t ]+\"[^\"]+\"))[\t ]+)?(struct|enum|union|mod|trait|fn|impl|macro_rules!)[< \t]+[^;]*)$",
/* -- */
"[a-zA-Z_][a-zA-Z0-9_]*"
"|[0-9][0-9_a-fA-Fiosuxz]*(\\.([0-9]*[eE][+-]?)?[0-9_fF]*)?"
"|[-+*\\/<>%&^|=!:]=|<<=?|>>=?|&&|\\|\\||->|=>|\\.{2}=|\\.{3}|::"),
PATTERNS("scheme",
"^[\t ]*(\\(((define|def(struct|syntax|class|method|rules|record|proto|alias)?)[-*/ \t]|(library|module|struct|class)[*+ \t]).*)$",
/*
* R7RS valid identifiers include any sequence enclosed
* within vertical lines having no backslashes
*/
"\\|([^\\\\]*)\\|"
/* All other words should be delimited by spaces or parentheses */
"|([^][)(}{[ \t])+"),
PATTERNS("tex", "^(\\\\((sub)*section|chapter|part)\\*{0,1}\\{.*)$",
"\\\\[a-zA-Z@]+|\\\\.|[a-zA-Z0-9\x80-\xff]+"),
{ "default", NULL, -1, { NULL, 0 } },
};
#undef PATTERNS
#undef IPATTERN
static struct userdiff_driver driver_true = {
"diff=true",
NULL,
0,
{ NULL, 0 }
};
static struct userdiff_driver driver_false = {
"!diff",
NULL,
1,
{ NULL, 0 }
};
struct find_by_namelen_data {
const char *name;
size_t len;
struct userdiff_driver *driver;
};
static int userdiff_find_by_namelen_cb(struct userdiff_driver *driver,
enum userdiff_driver_type type, void *priv)
{
struct find_by_namelen_data *cb_data = priv;
if (!strncmp(driver->name, cb_data->name, cb_data->len) &&
!driver->name[cb_data->len]) {
cb_data->driver = driver;
return 1; /* tell the caller to stop iterating */
}
return 0;
}
static struct userdiff_driver *userdiff_find_by_namelen(const char *name, size_t len)
{
struct find_by_namelen_data udcbdata = {
.name = name,
.len = len,
};
for_each_userdiff_driver(userdiff_find_by_namelen_cb, &udcbdata);
return udcbdata.driver;
}
static int parse_funcname(struct userdiff_funcname *f, const char *k,
const char *v, int cflags)
{
if (git_config_string(&f->pattern, k, v) < 0)
return -1;
f->cflags = cflags;
return 0;
}
static int parse_tristate(int *b, const char *k, const char *v)
{
if (v && !strcasecmp(v, "auto"))
*b = -1;
else
*b = git_config_bool(k, v);
return 0;
}
static int parse_bool(int *b, const char *k, const char *v)
{
*b = git_config_bool(k, v);
return 0;
}
int userdiff_config(const char *k, const char *v)
{
struct userdiff_driver *drv;
const char *name, *type;
size_t namelen;
if (parse_config_key(k, "diff", &name, &namelen, &type) || !name)
return 0;
drv = userdiff_find_by_namelen(name, namelen);
if (!drv) {
ALLOC_GROW(drivers, ndrivers+1, drivers_alloc);
drv = &drivers[ndrivers++];
memset(drv, 0, sizeof(*drv));
drv->name = xmemdupz(name, namelen);
drv->binary = -1;
}
if (!strcmp(type, "funcname"))
return parse_funcname(&drv->funcname, k, v, 0);
if (!strcmp(type, "xfuncname"))
return parse_funcname(&drv->funcname, k, v, REG_EXTENDED);
if (!strcmp(type, "binary"))
return parse_tristate(&drv->binary, k, v);
if (!strcmp(type, "command"))
return git_config_string(&drv->external, k, v);
if (!strcmp(type, "textconv"))
return git_config_string(&drv->textconv, k, v);
if (!strcmp(type, "cachetextconv"))
return parse_bool(&drv->textconv_want_cache, k, v);
if (!strcmp(type, "wordregex"))
return git_config_string(&drv->word_regex, k, v);
return 0;
}
struct userdiff_driver *userdiff_find_by_name(const char *name)
{
int len = strlen(name);
return userdiff_find_by_namelen(name, len);
}
struct userdiff_driver *userdiff_find_by_path(struct index_state *istate,
const char *path)
{
static struct attr_check *check;
if (!check)
check = attr_check_initl("diff", NULL);
if (!path)
return NULL;
git_check_attr(istate, path, check);
if (ATTR_TRUE(check->items[0].value))
return &driver_true;
if (ATTR_FALSE(check->items[0].value))
return &driver_false;
if (ATTR_UNSET(check->items[0].value))
return NULL;
return userdiff_find_by_name(check->items[0].value);
}
struct userdiff_driver *userdiff_get_textconv(struct repository *r,
struct userdiff_driver *driver)
{
if (!driver->textconv)
return NULL;
if (driver->textconv_want_cache && !driver->textconv_cache) {
struct notes_cache *c = xmalloc(sizeof(*c));
struct strbuf name = STRBUF_INIT;
strbuf_addf(&name, "textconv/%s", driver->name);
notes_cache_init(r, c, name.buf, driver->textconv);
driver->textconv_cache = c;
strbuf_release(&name);
}
return driver;
}
static int for_each_userdiff_driver_list(each_userdiff_driver_fn fn,
enum userdiff_driver_type type, void *cb_data,
struct userdiff_driver *drv,
int drv_size)
{
int i;
int ret;
for (i = 0; i < drv_size; i++) {
struct userdiff_driver *item = drv + i;
if ((ret = fn(item, type, cb_data)))
return ret;
}
return 0;
}
int for_each_userdiff_driver(each_userdiff_driver_fn fn, void *cb_data)
{
int ret;
ret = for_each_userdiff_driver_list(fn, USERDIFF_DRIVER_TYPE_CUSTOM,
cb_data, drivers, ndrivers);
if (ret)
return ret;
ret = for_each_userdiff_driver_list(fn, USERDIFF_DRIVER_TYPE_BUILTIN,
cb_data, builtin_drivers,
ARRAY_SIZE(builtin_drivers));
if (ret)
return ret;
return 0;
}