/*
* $Id: ruby.c 571 2007-06-24 23:32:14Z elliotth $
*
* Copyright (c) 2000-2001, Thaddeus Covert <sahuagin@mediaone.net>
* Copyright (c) 2002 Matthias Veit <matthias_veit@yahoo.de>
* Copyright (c) 2004 Elliott Hughes <enh@acm.org>
*
* This source code is released for free distribution under the terms of the
* GNU General Public License.
*
* This module contains functions for generating tags for Ruby language
* files.
*/
/*
* INCLUDE FILES
*/
#include "general.h" /* must always come first */
#include <string.h>
#include "entry.h"
#include "parse.h"
#include "read.h"
#include "vstring.h"
/*
* DATA DECLARATIONS
*/
typedef enum {
K_UNDEFINED = -1, K_CLASS, K_METHOD, K_MODULE, K_SINGLETON
} rubyKind;
/*
* DATA DEFINITIONS
*/
static kindOption RubyKinds [] = {
{ TRUE, 'c', "class", "classes" },
{ TRUE, 'f', "method", "methods" },
{ TRUE, 'm', "module", "modules" },
{ TRUE, 'F', "singleton method", "singleton methods" }
};
static stringList* nesting = 0;
/*
* FUNCTION DEFINITIONS
*/
/*
* Returns a string describing the scope in 'list'.
* We record the current scope as a list of entered scopes.
* Scopes corresponding to 'if' statements and the like are
* represented by empty strings. Scopes corresponding to
* modules and classes are represented by the name of the
* module or class.
*/
static vString* stringListToScope (const stringList* list)
{
unsigned int i;
unsigned int chunks_output = 0;
vString* result = vStringNew ();
const unsigned int max = stringListCount (list);
for (i = 0; i < max; ++i)
{
vString* chunk = stringListItem (list, i);
if (vStringLength (chunk) > 0)
{
vStringCatS (result, (chunks_output++ > 0) ? "." : "");
vStringCatS (result, vStringValue (chunk));
}
}
return result;
}
/*
* Attempts to advance 's' past 'literal'.
* Returns TRUE if it did, FALSE (and leaves 's' where
* it was) otherwise.
*/
static boolean canMatch (const unsigned char** s, const char* literal)
{
const int literal_length = strlen (literal);
const unsigned char next_char = *(*s + literal_length);
if (strncmp ((const char*) *s, literal, literal_length) != 0)
{
return FALSE;
}
/* Additionally check that we're at the end of a token. */
if ( ! (next_char == 0 || isspace (next_char) || next_char == '('))
{
return FALSE;
}
*s += literal_length;
return TRUE;
}
/*
* Attempts to advance 'cp' past a Ruby operator method name. Returns
* TRUE if successful (and copies the name into 'name'), FALSE otherwise.
*/
static boolean parseRubyOperator (vString* name, const unsigned char** cp)
{
static const char* RUBY_OPERATORS[] = {
"[]", "[]=",
"**",
"!", "~", "+@", "-@",
"*", "/", "%",
"+", "-",
">>", "<<",
"&",
"^", "|",
"<=", "<", ">", ">=",
"<=>", "==", "===", "!=", "=~", "!~",
"`",
0
};
int i;
for (i = 0; RUBY_OPERATORS[i] != 0; ++i)
{
if (canMatch (cp, RUBY_OPERATORS[i]))
{
vStringCatS (name, RUBY_OPERATORS[i]);
return TRUE;
}
}
return FALSE;
}
/*
* Emits a tag for the given 'name' of kind 'kind' at the current nesting.
*/
static void emitRubyTag (vString* name, rubyKind kind)
{
tagEntryInfo tag;
vString* scope;
vStringTerminate (name);
scope = stringListToScope (nesting);
initTagEntry (&tag, vStringValue (name));
if (vStringLength (scope) > 0) {
tag.extensionFields.scope [0] = "class";
tag.extensionFields.scope [1] = vStringValue (scope);
}
tag.kindName = RubyKinds [kind].name;
tag.kind = RubyKinds [kind].letter;
makeTagEntry (&tag);
stringListAdd (nesting, vStringNewCopy (name));
vStringClear (name);
vStringDelete (scope);
}
/* Tests whether 'ch' is a character in 'list'. */
static boolean charIsIn (char ch, const char* list)
{
return (strchr (list, ch) != 0);
}
/* Advances 'cp' over leading whitespace. */
static void skipWhitespace (const unsigned char** cp)
{
while (isspace (**cp))
{
++*cp;
}
}
/*
* Copies the characters forming an identifier from *cp into
* name, leaving *cp pointing to the character after the identifier.
*/
static rubyKind parseIdentifier (
const unsigned char** cp, vString* name, rubyKind kind)
{
/* Method names are slightly different to class and variable names.
* A method name may optionally end with a question mark, exclamation
* point or equals sign. These are all part of the name.
* A method name may also contain a period if it's a singleton method.
*/
const char* also_ok = (kind == K_METHOD) ? "_.?!=" : "_";
skipWhitespace (cp);
/* Check for an anonymous (singleton) class such as "class << HTTP". */
if (kind == K_CLASS && **cp == '<' && *(*cp + 1) == '<')
{
return K_UNDEFINED;
}
/* Check for operators such as "def []=(key, val)". */
if (kind == K_METHOD || kind == K_SINGLETON)
{
if (parseRubyOperator (name, cp))
{
return kind;
}
}
/* Copy the identifier into 'name'. */
while (**cp != 0 && (isalnum (**cp) || charIsIn (**cp, also_ok)))
{
char last_char = **cp;
vStringPut (name, last_char);
++*cp;
if (kind == K_METHOD)
{
/* Recognize singleton methods. */
if (last_char == '.')
{
vStringTerminate (name);
vStringClear (name);
return parseIdentifier (cp, name, K_SINGLETON);
}
/* Recognize characters which mark the end of a method name. */
if (charIsIn (last_char, "?!="))
{
break;
}
}
}
return kind;
}
static void readAndEmitTag (const unsigned char** cp, rubyKind expected_kind)
{
if (isspace (**cp))
{
vString *name = vStringNew ();
rubyKind actual_kind = parseIdentifier (cp, name, expected_kind);
if (actual_kind == K_UNDEFINED || vStringLength (name) == 0)
{
/*
* What kind of tags should we create for code like this?
*
* %w(self.clfloor clfloor).each do |name|
* module_eval <<-"end;"
* def #{name}(x, y=1)
* q, r = x.divmod(y)
* q = q.to_i
* return q, r
* end
* end;
* end
*
* Or this?
*
* class << HTTP
*
* For now, we don't create any.
*/
}
else
{
emitRubyTag (name, actual_kind);
}
vStringDelete (name);
}
}
static void enterUnnamedScope (void)
{
stringListAdd (nesting, vStringNewInit (""));
}
static void findRubyTags (void)
{
const unsigned char *line;
boolean inMultiLineComment = FALSE;
nesting = stringListNew ();
/* FIXME: this whole scheme is wrong, because Ruby isn't line-based.
* You could perfectly well write:
*
* def
* method
* puts("hello")
* end
*
* if you wished, and this function would fail to recognize anything.
*/
while ((line = fileReadLine ()) != NULL)
{
const unsigned char *cp = line;
if (canMatch (&cp, "=begin"))
{
inMultiLineComment = TRUE;
continue;
}
if (canMatch (&cp, "=end"))
{
inMultiLineComment = FALSE;
continue;
}
skipWhitespace (&cp);
/* Avoid mistakenly starting a scope for modifiers such as
*
* return if <exp>
*
* FIXME: this is fooled by code such as
*
* result = if <exp>
* <a>
* else
* <b>
* end
*
* FIXME: we're also fooled if someone does something heinous such as
*
* puts("hello") \
* unless <exp>
*/
if (canMatch (&cp, "case") || canMatch (&cp, "for") ||
canMatch (&cp, "if") || canMatch (&cp, "unless") ||
canMatch (&cp, "while"))
{
enterUnnamedScope ();
}
/*
* "module M", "class C" and "def m" should only be at the beginning
* of a line.
*/
if (canMatch (&cp, "module"))
{
readAndEmitTag (&cp, K_MODULE);
}
else if (canMatch (&cp, "class"))
{
readAndEmitTag (&cp, K_CLASS);
}
else if (canMatch (&cp, "def"))
{
readAndEmitTag (&cp, K_METHOD);
}
while (*cp != '\0')
{
/* FIXME: we don't cope with here documents,
* or regular expression literals, or ... you get the idea.
* Hopefully, the restriction above that insists on seeing
* definitions at the starts of lines should keep us out of
* mischief.
*/
if (inMultiLineComment || isspace (*cp))
{
++cp;
}
else if (*cp == '#')
{
/* FIXME: this is wrong, but there *probably* won't be a
* definition after an interpolated string (where # doesn't
* mean 'comment').
*/
break;
}
else if (canMatch (&cp, "begin") || canMatch (&cp, "do"))
{
enterUnnamedScope ();
}
else if (canMatch (&cp, "end") && stringListCount (nesting) > 0)
{
/* Leave the most recent scope. */
vStringDelete (stringListLast (nesting));
stringListRemoveLast (nesting);
}
else if (*cp == '"')
{
/* Skip string literals.
* FIXME: should cope with escapes and interpolation.
*/
do {
++cp;
} while (*cp != 0 && *cp != '"');
}
else if (*cp != '\0')
{
do
++cp;
while (isalnum (*cp) || *cp == '_');
}
}
}
stringListDelete (nesting);
}
extern parserDefinition* RubyParser (void)
{
static const char *const extensions [] = { "rb", "ruby", NULL };
parserDefinition* def = parserNew ("Ruby");
def->kinds = RubyKinds;
def->kindCount = KIND_COUNT (RubyKinds);
def->extensions = extensions;
def->parser = findRubyTags;
return def;
}
/* vi:set tabstop=4 shiftwidth=4: */
|
