/** @file LexRust.cxx
** Lexer for Rust.
**
** Copyright (c) 2013 by SiegeLord <slabode@aim.com>
** Converted to lexer object and added further folding features/properties by "Udo Lechner" <dlchnr(at)gmx(dot)net>
**/
// Copyright 1998-2005 by Neil Hodgson <neilh@scintilla.org>
// The License.txt file describes the conditions under which this software may be distributed.
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <stdarg.h>
#include <assert.h>
#include <ctype.h>
#include <string>
#include <map>
#include "ILexer.h"
#include "Scintilla.h"
#include "SciLexer.h"
#include "PropSetSimple.h"
#include "WordList.h"
#include "LexAccessor.h"
#include "Accessor.h"
#include "StyleContext.h"
#include "CharacterSet.h"
#include "LexerModule.h"
#include "OptionSet.h"
#ifdef SCI_NAMESPACE
using namespace Scintilla;
#endif
static const int NUM_RUST_KEYWORD_LISTS = 7;
static const int MAX_RUST_IDENT_CHARS = 1023;
static bool IsStreamCommentStyle(int style) {
return style == SCE_RUST_COMMENTBLOCK ||
style == SCE_RUST_COMMENTBLOCKDOC;
}
// Options used for LexerRust
struct OptionsRust {
bool fold;
bool foldSyntaxBased;
bool foldComment;
bool foldCommentMultiline;
bool foldCommentExplicit;
std::string foldExplicitStart;
std::string foldExplicitEnd;
bool foldExplicitAnywhere;
bool foldCompact;
int foldAtElseInt;
bool foldAtElse;
OptionsRust() {
fold = false;
foldSyntaxBased = true;
foldComment = false;
foldCommentMultiline = true;
foldCommentExplicit = true;
foldExplicitStart = "";
foldExplicitEnd = "";
foldExplicitAnywhere = false;
foldCompact = true;
foldAtElseInt = -1;
foldAtElse = false;
}
};
static const char * const rustWordLists[NUM_RUST_KEYWORD_LISTS + 1] = {
"Primary keywords and identifiers",
"Built in types",
"Other keywords",
"Keywords 4",
"Keywords 5",
"Keywords 6",
"Keywords 7",
0,
};
struct OptionSetRust : public OptionSet<OptionsRust> {
OptionSetRust() {
DefineProperty("fold", &OptionsRust::fold);
DefineProperty("fold.comment", &OptionsRust::foldComment);
DefineProperty("fold.compact", &OptionsRust::foldCompact);
DefineProperty("fold.at.else", &OptionsRust::foldAtElse);
DefineProperty("fold.rust.syntax.based", &OptionsRust::foldSyntaxBased,
"Set this property to 0 to disable syntax based folding.");
DefineProperty("fold.rust.comment.multiline", &OptionsRust::foldCommentMultiline,
"Set this property to 0 to disable folding multi-line comments when fold.comment=1.");
DefineProperty("fold.rust.comment.explicit", &OptionsRust::foldCommentExplicit,
"Set this property to 0 to disable folding explicit fold points when fold.comment=1.");
DefineProperty("fold.rust.explicit.start", &OptionsRust::foldExplicitStart,
"The string to use for explicit fold start points, replacing the standard //{.");
DefineProperty("fold.rust.explicit.end", &OptionsRust::foldExplicitEnd,
"The string to use for explicit fold end points, replacing the standard //}.");
DefineProperty("fold.rust.explicit.anywhere", &OptionsRust::foldExplicitAnywhere,
"Set this property to 1 to enable explicit fold points anywhere, not just in line comments.");
DefineProperty("lexer.rust.fold.at.else", &OptionsRust::foldAtElseInt,
"This option enables Rust folding on a \"} else {\" line of an if statement.");
DefineWordListSets(rustWordLists);
}
};
class LexerRust : public ILexer {
WordList keywords[NUM_RUST_KEYWORD_LISTS];
OptionsRust options;
OptionSetRust osRust;
public:
virtual ~LexerRust() {
}
void SCI_METHOD Release() {
delete this;
}
int SCI_METHOD Version() const {
return lvOriginal;
}
const char * SCI_METHOD PropertyNames() {
return osRust.PropertyNames();
}
int SCI_METHOD PropertyType(const char *name) {
return osRust.PropertyType(name);
}
const char * SCI_METHOD DescribeProperty(const char *name) {
return osRust.DescribeProperty(name);
}
Sci_Position SCI_METHOD PropertySet(const char *key, const char *val);
const char * SCI_METHOD DescribeWordListSets() {
return osRust.DescribeWordListSets();
}
Sci_Position SCI_METHOD WordListSet(int n, const char *wl);
void SCI_METHOD Lex(Sci_PositionU startPos, Sci_Position length, int initStyle, IDocument *pAccess);
void SCI_METHOD Fold(Sci_PositionU startPos, Sci_Position length, int initStyle, IDocument *pAccess);
void * SCI_METHOD PrivateCall(int, void *) {
return 0;
}
static ILexer *LexerFactoryRust() {
return new LexerRust();
}
};
Sci_Position SCI_METHOD LexerRust::PropertySet(const char *key, const char *val) {
if (osRust.PropertySet(&options, key, val)) {
return 0;
}
return -1;
}
Sci_Position SCI_METHOD LexerRust::WordListSet(int n, const char *wl) {
Sci_Position firstModification = -1;
if (n < NUM_RUST_KEYWORD_LISTS) {
WordList *wordListN = &keywords[n];
WordList wlNew;
wlNew.Set(wl);
if (*wordListN != wlNew) {
wordListN->Set(wl);
firstModification = 0;
}
}
return firstModification;
}
static bool IsWhitespace(int c) {
return c == ' ' || c == '\t' || c == '\r' || c == '\n';
}
/* This isn't quite right for Unicode identifiers */
static bool IsIdentifierStart(int ch) {
return (IsASCII(ch) && (isalpha(ch) || ch == '_')) || !IsASCII(ch);
}
/* This isn't quite right for Unicode identifiers */
static bool IsIdentifierContinue(int ch) {
return (IsASCII(ch) && (isalnum(ch) || ch == '_')) || !IsASCII(ch);
}
static void ScanWhitespace(Accessor& styler, Sci_Position& pos, Sci_Position max) {
while (IsWhitespace(styler.SafeGetCharAt(pos, '\0')) && pos < max) {
if (pos == styler.LineEnd(styler.GetLine(pos)))
styler.SetLineState(styler.GetLine(pos), 0);
pos++;
}
styler.ColourTo(pos-1, SCE_RUST_DEFAULT);
}
static void GrabString(char* s, Accessor& styler, Sci_Position start, Sci_Position len) {
for (Sci_Position ii = 0; ii < len; ii++)
s[ii] = styler[ii + start];
s[len] = '\0';
}
static void ScanIdentifier(Accessor& styler, Sci_Position& pos, WordList *keywords) {
Sci_Position start = pos;
while (IsIdentifierContinue(styler.SafeGetCharAt(pos, '\0')))
pos++;
if (styler.SafeGetCharAt(pos, '\0') == '!') {
pos++;
styler.ColourTo(pos - 1, SCE_RUST_MACRO);
} else {
char s[MAX_RUST_IDENT_CHARS + 1];
int len = pos - start;
len = len > MAX_RUST_IDENT_CHARS ? MAX_RUST_IDENT_CHARS : len;
GrabString(s, styler, start, len);
bool keyword = false;
for (int ii = 0; ii < NUM_RUST_KEYWORD_LISTS; ii++) {
if (keywords[ii].InList(s)) {
styler.ColourTo(pos - 1, SCE_RUST_WORD + ii);
keyword = true;
break;
}
}
if (!keyword) {
styler.ColourTo(pos - 1, SCE_RUST_IDENTIFIER);
}
}
}
/* Scans a sequence of digits, returning true if it found any. */
static bool ScanDigits(Accessor& styler, Sci_Position& pos, int base) {
Sci_Position old_pos = pos;
for (;;) {
int c = styler.SafeGetCharAt(pos, '\0');
if (IsADigit(c, base) || c == '_')
pos++;
else
break;
}
return old_pos != pos;
}
/* Scans an integer and floating point literals. */
static void ScanNumber(Accessor& styler, Sci_Position& pos) {
int base = 10;
int c = styler.SafeGetCharAt(pos, '\0');
int n = styler.SafeGetCharAt(pos + 1, '\0');
bool error = false;
/* Scan the prefix, thus determining the base.
* 10 is default if there's no prefix. */
if (c == '0' && n == 'x') {
pos += 2;
base = 16;
} else if (c == '0' && n == 'b') {
pos += 2;
base = 2;
} else if (c == '0' && n == 'o') {
pos += 2;
base = 8;
}
/* Scan initial digits. The literal is malformed if there are none. */
error |= !ScanDigits(styler, pos, base);
/* See if there's an integer suffix. We mimic the Rust's lexer
* and munch it even if there was an error above. */
c = styler.SafeGetCharAt(pos, '\0');
if (c == 'u' || c == 'i') {
pos++;
c = styler.SafeGetCharAt(pos, '\0');
n = styler.SafeGetCharAt(pos + 1, '\0');
if (c == '8' || c == 's') {
pos++;
} else if (c == '1' && n == '6') {
pos += 2;
} else if (c == '3' && n == '2') {
pos += 2;
} else if (c == '6' && n == '4') {
pos += 2;
} else {
error = true;
}
/* See if it's a floating point literal. These literals have to be base 10.
*/
} else if (!error) {
/* If there's a period, it's a floating point literal unless it's
* followed by an identifier (meaning this is a method call, e.g.
* `1.foo()`) or another period, in which case it's a range (e.g. 1..2)
*/
n = styler.SafeGetCharAt(pos + 1, '\0');
if (c == '.' && !(IsIdentifierStart(n) || n == '.')) {
error |= base != 10;
pos++;
/* It's ok to have no digits after the period. */
ScanDigits(styler, pos, 10);
}
/* Look for the exponentiation. */
c = styler.SafeGetCharAt(pos, '\0');
if (c == 'e' || c == 'E') {
error |= base != 10;
pos++;
c = styler.SafeGetCharAt(pos, '\0');
if (c == '-' || c == '+')
pos++;
/* It is invalid to have no digits in the exponent. */
error |= !ScanDigits(styler, pos, 10);
}
/* Scan the floating point suffix. */
c = styler.SafeGetCharAt(pos, '\0');
if (c == 'f') {
error |= base != 10;
pos++;
c = styler.SafeGetCharAt(pos, '\0');
n = styler.SafeGetCharAt(pos + 1, '\0');
if (c == '3' && n == '2') {
pos += 2;
} else if (c == '6' && n == '4') {
pos += 2;
} else {
error = true;
}
}
}
if (error)
styler.ColourTo(pos - 1, SCE_RUST_LEXERROR);
else
styler.ColourTo(pos - 1, SCE_RUST_NUMBER);
}
static bool IsOneCharOperator(int c) {
return c == ';' || c == ',' || c == '(' || c == ')'
|| c == '{' || c == '}' || c == '[' || c == ']'
|| c == '@' || c == '#' || c == '~' || c == '+'
|| c == '*' || c == '/' || c == '^' || c == '%'
|| c == '.' || c == ':' || c == '!' || c == '<'
|| c == '>' || c == '=' || c == '-' || c == '&'
|| c == '|' || c == '$';
}
static bool IsTwoCharOperator(int c, int n) {
return (c == '.' && n == '.') || (c == ':' && n == ':')
|| (c == '!' && n == '=') || (c == '<' && n == '<')
|| (c == '<' && n == '=') || (c == '>' && n == '>')
|| (c == '>' && n == '=') || (c == '=' && n == '=')
|| (c == '=' && n == '>') || (c == '-' && n == '>')
|| (c == '&' && n == '&') || (c == '|' && n == '|')
|| (c == '-' && n == '=') || (c == '&' && n == '=')
|| (c == '|' && n == '=') || (c == '+' && n == '=')
|| (c == '*' && n == '=') || (c == '/' && n == '=')
|| (c == '^' && n == '=') || (c == '%' && n == '=');
}
static bool IsThreeCharOperator(int c, int n, int n2) {
return (c == '<' && n == '<' && n2 == '=')
|| (c == '>' && n == '>' && n2 == '=');
}
static bool IsValidCharacterEscape(int c) {
return c == 'n' || c == 'r' || c == 't' || c == '\\'
|| c == '\'' || c == '"' || c == '0';
}
static bool IsValidStringEscape(int c) {
return IsValidCharacterEscape(c) || c == '\n' || c == '\r';
}
static bool ScanNumericEscape(Accessor &styler, Sci_Position& pos, Sci_Position num_digits, bool stop_asap) {
for (;;) {
int c = styler.SafeGetCharAt(pos, '\0');
if (!IsADigit(c, 16))
break;
num_digits--;
pos++;
if (num_digits == 0 && stop_asap)
return true;
}
if (num_digits == 0) {
return true;
} else {
return false;
}
}
/* This is overly permissive for character literals in order to accept UTF-8 encoded
* character literals. */
static void ScanCharacterLiteralOrLifetime(Accessor &styler, Sci_Position& pos, bool ascii_only) {
pos++;
int c = styler.SafeGetCharAt(pos, '\0');
int n = styler.SafeGetCharAt(pos + 1, '\0');
bool done = false;
bool valid_lifetime = !ascii_only && IsIdentifierStart(c);
bool valid_char = true;
bool first = true;
while (!done) {
switch (c) {
case '\\':
done = true;
if (IsValidCharacterEscape(n)) {
pos += 2;
} else if (n == 'x') {
pos += 2;
valid_char = ScanNumericEscape(styler, pos, 2, false);
} else if (n == 'u' && !ascii_only) {
pos += 2;
valid_char = ScanNumericEscape(styler, pos, 4, false);
} else if (n == 'U' && !ascii_only) {
pos += 2;
valid_char = ScanNumericEscape(styler, pos, 8, false);
} else {
valid_char = false;
}
break;
case '\'':
valid_char = !first;
done = true;
break;
case '\t':
case '\n':
case '\r':
case '\0':
valid_char = false;
done = true;
break;
default:
if (ascii_only && !IsASCII((char)c)) {
done = true;
valid_char = false;
} else if (!IsIdentifierContinue(c) && !first) {
done = true;
} else {
pos++;
}
break;
}
c = styler.SafeGetCharAt(pos, '\0');
n = styler.SafeGetCharAt(pos + 1, '\0');
first = false;
}
if (styler.SafeGetCharAt(pos, '\0') == '\'') {
valid_lifetime = false;
} else {
valid_char = false;
}
if (valid_lifetime) {
styler.ColourTo(pos - 1, SCE_RUST_LIFETIME);
} else if (valid_char) {
pos++;
styler.ColourTo(pos - 1, ascii_only ? SCE_RUST_BYTECHARACTER : SCE_RUST_CHARACTER);
} else {
styler.ColourTo(pos - 1, SCE_RUST_LEXERROR);
}
}
enum CommentState {
UnknownComment,
DocComment,
NotDocComment
};
/*
* The rule for block-doc comments is as follows: /xxN and /x! (where x is an asterisk, N is a non-asterisk) start doc comments.
* Otherwise it's a regular comment.
*/
static void ResumeBlockComment(Accessor &styler, Sci_Position& pos, Sci_Position max, CommentState state, int level) {
int c = styler.SafeGetCharAt(pos, '\0');
bool maybe_doc_comment = false;
if (c == '*') {
int n = styler.SafeGetCharAt(pos + 1, '\0');
if (n != '*' && n != '/') {
maybe_doc_comment = true;
}
} else if (c == '!') {
maybe_doc_comment = true;
}
for (;;) {
int n = styler.SafeGetCharAt(pos + 1, '\0');
if (pos == styler.LineEnd(styler.GetLine(pos)))
styler.SetLineState(styler.GetLine(pos), level);
if (c == '*') {
pos++;
if (n == '/') {
pos++;
level--;
if (level == 0) {
styler.SetLineState(styler.GetLine(pos), 0);
if (state == DocComment || (state == UnknownComment && maybe_doc_comment))
styler.ColourTo(pos - 1, SCE_RUST_COMMENTBLOCKDOC);
else
styler.ColourTo(pos - 1, SCE_RUST_COMMENTBLOCK);
break;
}
}
} else if (c == '/') {
pos++;
if (n == '*') {
pos++;
level++;
}
}
else {
pos++;
}
if (pos >= max) {
if (state == DocComment || (state == UnknownComment && maybe_doc_comment))
styler.ColourTo(pos - 1, SCE_RUST_COMMENTBLOCKDOC);
else
styler.ColourTo(pos - 1, SCE_RUST_COMMENTBLOCK);
break;
}
c = styler.SafeGetCharAt(pos, '\0');
}
}
/*
* The rule for line-doc comments is as follows... ///N and //! (where N is a non slash) start doc comments.
* Otherwise it's a normal line comment.
*/
static void ResumeLineComment(Accessor &styler, Sci_Position& pos, Sci_Position max, CommentState state) {
bool maybe_doc_comment = false;
int c = styler.SafeGetCharAt(pos, '\0');
if (c == '/') {
if (pos < max) {
pos++;
c = styler.SafeGetCharAt(pos, '\0');
if (c != '/') {
maybe_doc_comment = true;
}
}
} else if (c == '!') {
maybe_doc_comment = true;
}
while (pos < max && c != '\n') {
if (pos == styler.LineEnd(styler.GetLine(pos)))
styler.SetLineState(styler.GetLine(pos), 0);
pos++;
c = styler.SafeGetCharAt(pos, '\0');
}
if (state == DocComment || (state == UnknownComment && maybe_doc_comment))
styler.ColourTo(pos - 1, SCE_RUST_COMMENTLINEDOC);
else
styler.ColourTo(pos - 1, SCE_RUST_COMMENTLINE);
}
static void ScanComments(Accessor &styler, Sci_Position& pos, Sci_Position max) {
pos++;
int c = styler.SafeGetCharAt(pos, '\0');
pos++;
if (c == '/')
ResumeLineComment(styler, pos, max, UnknownComment);
else if (c == '*')
ResumeBlockComment(styler, pos, max, UnknownComment, 1);
}
static void ResumeString(Accessor &styler, Sci_Position& pos, Sci_Position max, bool ascii_only) {
int c = styler.SafeGetCharAt(pos, '\0');
bool error = false;
while (c != '"' && !error) {
if (pos >= max) {
error = true;
break;
}
if (pos == styler.LineEnd(styler.GetLine(pos)))
styler.SetLineState(styler.GetLine(pos), 0);
if (c == '\\') {
int n = styler.SafeGetCharAt(pos + 1, '\0');
if (IsValidStringEscape(n)) {
pos += 2;
} else if (n == 'x') {
pos += 2;
error = !ScanNumericEscape(styler, pos, 2, true);
} else if (n == 'u' && !ascii_only) {
pos += 2;
error = !ScanNumericEscape(styler, pos, 4, true);
} else if (n == 'U' && !ascii_only) {
pos += 2;
error = !ScanNumericEscape(styler, pos, 8, true);
} else {
pos += 1;
error = true;
}
} else {
if (ascii_only && !IsASCII((char)c))
error = true;
else
pos++;
}
c = styler.SafeGetCharAt(pos, '\0');
}
if (!error)
pos++;
styler.ColourTo(pos - 1, ascii_only ? SCE_RUST_BYTESTRING : SCE_RUST_STRING);
}
static void ResumeRawString(Accessor &styler, Sci_Position& pos, Sci_Position max, int num_hashes, bool ascii_only) {
for (;;) {
if (pos == styler.LineEnd(styler.GetLine(pos)))
styler.SetLineState(styler.GetLine(pos), num_hashes);
int c = styler.SafeGetCharAt(pos, '\0');
if (c == '"') {
pos++;
int trailing_num_hashes = 0;
while (styler.SafeGetCharAt(pos, '\0') == '#' && trailing_num_hashes < num_hashes) {
trailing_num_hashes++;
pos++;
}
if (trailing_num_hashes == num_hashes) {
styler.SetLineState(styler.GetLine(pos), 0);
break;
}
} else if (pos >= max) {
break;
} else {
if (ascii_only && !IsASCII((char)c))
break;
pos++;
}
}
styler.ColourTo(pos - 1, ascii_only ? SCE_RUST_BYTESTRINGR : SCE_RUST_STRINGR);
}
static void ScanRawString(Accessor &styler, Sci_Position& pos, Sci_Position max, bool ascii_only) {
pos++;
int num_hashes = 0;
while (styler.SafeGetCharAt(pos, '\0') == '#') {
num_hashes++;
pos++;
}
if (styler.SafeGetCharAt(pos, '\0') != '"') {
styler.ColourTo(pos - 1, SCE_RUST_LEXERROR);
} else {
pos++;
ResumeRawString(styler, pos, max, num_hashes, ascii_only);
}
}
void SCI_METHOD LexerRust::Lex(Sci_PositionU startPos, Sci_Position length, int initStyle, IDocument *pAccess) {
PropSetSimple props;
Accessor styler(pAccess, &props);
Sci_Position pos = startPos;
Sci_Position max = pos + length;
styler.StartAt(pos);
styler.StartSegment(pos);
if (initStyle == SCE_RUST_COMMENTBLOCK || initStyle == SCE_RUST_COMMENTBLOCKDOC) {
ResumeBlockComment(styler, pos, max, initStyle == SCE_RUST_COMMENTBLOCKDOC ? DocComment : NotDocComment, styler.GetLineState(styler.GetLine(pos) - 1));
} else if (initStyle == SCE_RUST_COMMENTLINE || initStyle == SCE_RUST_COMMENTLINEDOC) {
ResumeLineComment(styler, pos, max, initStyle == SCE_RUST_COMMENTLINEDOC ? DocComment : NotDocComment);
} else if (initStyle == SCE_RUST_STRING) {
ResumeString(styler, pos, max, false);
} else if (initStyle == SCE_RUST_BYTESTRING) {
ResumeString(styler, pos, max, true);
} else if (initStyle == SCE_RUST_STRINGR) {
ResumeRawString(styler, pos, max, styler.GetLineState(styler.GetLine(pos) - 1), false);
} else if (initStyle == SCE_RUST_BYTESTRINGR) {
ResumeRawString(styler, pos, max, styler.GetLineState(styler.GetLine(pos) - 1), true);
}
while (pos < max) {
int c = styler.SafeGetCharAt(pos, '\0');
int n = styler.SafeGetCharAt(pos + 1, '\0');
int n2 = styler.SafeGetCharAt(pos + 2, '\0');
if (pos == 0 && c == '#' && n == '!' && n2 != '[') {
pos += 2;
ResumeLineComment(styler, pos, max, NotDocComment);
} else if (IsWhitespace(c)) {
ScanWhitespace(styler, pos, max);
} else if (c == '/' && (n == '/' || n == '*')) {
ScanComments(styler, pos, max);
} else if (c == 'r' && (n == '#' || n == '"')) {
ScanRawString(styler, pos, max, false);
} else if (c == 'b' && n == 'r' && (n2 == '#' || n2 == '"')) {
pos++;
ScanRawString(styler, pos, max, true);
} else if (c == 'b' && n == '"') {
pos += 2;
ResumeString(styler, pos, max, true);
} else if (c == 'b' && n == '\'') {
pos++;
ScanCharacterLiteralOrLifetime(styler, pos, true);
} else if (IsIdentifierStart(c)) {
ScanIdentifier(styler, pos, keywords);
} else if (IsADigit(c)) {
ScanNumber(styler, pos);
} else if (IsThreeCharOperator(c, n, n2)) {
pos += 3;
styler.ColourTo(pos - 1, SCE_RUST_OPERATOR);
} else if (IsTwoCharOperator(c, n)) {
pos += 2;
styler.ColourTo(pos - 1, SCE_RUST_OPERATOR);
} else if (IsOneCharOperator(c)) {
pos++;
styler.ColourTo(pos - 1, SCE_RUST_OPERATOR);
} else if (c == '\'') {
ScanCharacterLiteralOrLifetime(styler, pos, false);
} else if (c == '"') {
pos++;
ResumeString(styler, pos, max, false);
} else {
pos++;
styler.ColourTo(pos - 1, SCE_RUST_LEXERROR);
}
}
styler.ColourTo(pos - 1, SCE_RUST_DEFAULT);
styler.Flush();
}
void SCI_METHOD LexerRust::Fold(Sci_PositionU startPos, Sci_Position length, int initStyle, IDocument *pAccess) {
if (!options.fold)
return;
LexAccessor styler(pAccess);
Sci_PositionU endPos = startPos + length;
int visibleChars = 0;
bool inLineComment = false;
Sci_Position lineCurrent = styler.GetLine(startPos);
int levelCurrent = SC_FOLDLEVELBASE;
if (lineCurrent > 0)
levelCurrent = styler.LevelAt(lineCurrent-1) >> 16;
Sci_PositionU lineStartNext = styler.LineStart(lineCurrent+1);
int levelMinCurrent = levelCurrent;
int levelNext = levelCurrent;
char chNext = styler[startPos];
int styleNext = styler.StyleAt(startPos);
int style = initStyle;
const bool userDefinedFoldMarkers = !options.foldExplicitStart.empty() && !options.foldExplicitEnd.empty();
for (Sci_PositionU i = startPos; i < endPos; i++) {
char ch = chNext;
chNext = styler.SafeGetCharAt(i + 1);
int stylePrev = style;
style = styleNext;
styleNext = styler.StyleAt(i + 1);
bool atEOL = i == (lineStartNext-1);
if ((style == SCE_RUST_COMMENTLINE) || (style == SCE_RUST_COMMENTLINEDOC))
inLineComment = true;
if (options.foldComment && options.foldCommentMultiline && IsStreamCommentStyle(style) && !inLineComment) {
if (!IsStreamCommentStyle(stylePrev)) {
levelNext++;
} else if (!IsStreamCommentStyle(styleNext) && !atEOL) {
// Comments don't end at end of line and the next character may be unstyled.
levelNext--;
}
}
if (options.foldComment && options.foldCommentExplicit && ((style == SCE_RUST_COMMENTLINE) || options.foldExplicitAnywhere)) {
if (userDefinedFoldMarkers) {
if (styler.Match(i, options.foldExplicitStart.c_str())) {
levelNext++;
} else if (styler.Match(i, options.foldExplicitEnd.c_str())) {
levelNext--;
}
} else {
if ((ch == '/') && (chNext == '/')) {
char chNext2 = styler.SafeGetCharAt(i + 2);
if (chNext2 == '{') {
levelNext++;
} else if (chNext2 == '}') {
levelNext--;
}
}
}
}
if (options.foldSyntaxBased && (style == SCE_RUST_OPERATOR)) {
if (ch == '{') {
// Measure the minimum before a '{' to allow
// folding on "} else {"
if (levelMinCurrent > levelNext) {
levelMinCurrent = levelNext;
}
levelNext++;
} else if (ch == '}') {
levelNext--;
}
}
if (!IsASpace(ch))
visibleChars++;
if (atEOL || (i == endPos-1)) {
int levelUse = levelCurrent;
if (options.foldSyntaxBased && options.foldAtElse) {
levelUse = levelMinCurrent;
}
int lev = levelUse | levelNext << 16;
if (visibleChars == 0 && options.foldCompact)
lev |= SC_FOLDLEVELWHITEFLAG;
if (levelUse < levelNext)
lev |= SC_FOLDLEVELHEADERFLAG;
if (lev != styler.LevelAt(lineCurrent)) {
styler.SetLevel(lineCurrent, lev);
}
lineCurrent++;
lineStartNext = styler.LineStart(lineCurrent+1);
levelCurrent = levelNext;
levelMinCurrent = levelCurrent;
if (atEOL && (i == static_cast<Sci_PositionU>(styler.Length()-1))) {
// There is an empty line at end of file so give it same level and empty
styler.SetLevel(lineCurrent, (levelCurrent | levelCurrent << 16) | SC_FOLDLEVELWHITEFLAG);
}
visibleChars = 0;
inLineComment = false;
}
}
}
LexerModule lmRust(SCLEX_RUST, LexerRust::LexerFactoryRust, "rust", rustWordLists);
