bgfx/3rdparty/scintilla/lexers/LexLaTeX.cxx
2015-06-08 17:07:35 -07:00

540 lines
15 KiB
C++

// Scintilla source code edit control
/** @file LexLaTeX.cxx
** Lexer for LaTeX2e.
**/
// Copyright 1998-2001 by Neil Hodgson <neilh@scintilla.org>
// The License.txt file describes the conditions under which this software may be distributed.
// Modified by G. HU in 2013. Added folding, syntax highting inside math environments, and changed some minor behaviors.
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <stdarg.h>
#include <assert.h>
#include <ctype.h>
#include <vector>
#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 "LexerBase.h"
#ifdef SCI_NAMESPACE
using namespace Scintilla;
#endif
using namespace std;
struct latexFoldSave {
latexFoldSave() : structLev(0) {
for (int i = 0; i < 8; ++i) openBegins[i] = 0;
}
latexFoldSave(const latexFoldSave &save) : structLev(save.structLev) {
for (int i = 0; i < 8; ++i) openBegins[i] = save.openBegins[i];
}
int openBegins[8];
int structLev;
};
class LexerLaTeX : public LexerBase {
private:
vector<int> modes;
void setMode(int line, int mode) {
if (line >= static_cast<int>(modes.size())) modes.resize(line + 1, 0);
modes[line] = mode;
}
int getMode(int line) {
if (line >= 0 && line < static_cast<int>(modes.size())) return modes[line];
return 0;
}
void truncModes(int numLines) {
if (static_cast<int>(modes.size()) > numLines * 2 + 256)
modes.resize(numLines + 128);
}
vector<latexFoldSave> saves;
void setSave(int line, const latexFoldSave &save) {
if (line >= static_cast<int>(saves.size())) saves.resize(line + 1);
saves[line] = save;
}
void getSave(int line, latexFoldSave &save) {
if (line >= 0 && line < static_cast<int>(saves.size())) save = saves[line];
else {
save.structLev = 0;
for (int i = 0; i < 8; ++i) save.openBegins[i] = 0;
}
}
void truncSaves(int numLines) {
if (static_cast<int>(saves.size()) > numLines * 2 + 256)
saves.resize(numLines + 128);
}
public:
static ILexer *LexerFactoryLaTeX() {
return new LexerLaTeX();
}
void SCI_METHOD Lex(unsigned int startPos, int length, int initStyle, IDocument *pAccess);
void SCI_METHOD Fold(unsigned int startPos, int length, int initStyle, IDocument *pAccess);
};
static bool latexIsSpecial(int ch) {
return (ch == '#') || (ch == '$') || (ch == '%') || (ch == '&') || (ch == '_') ||
(ch == '{') || (ch == '}') || (ch == ' ');
}
static bool latexIsBlank(int ch) {
return (ch == ' ') || (ch == '\t');
}
static bool latexIsBlankAndNL(int ch) {
return (ch == ' ') || (ch == '\t') || (ch == '\r') || (ch == '\n');
}
static bool latexIsLetter(int ch) {
return IsASCII(ch) && isalpha(ch);
}
static bool latexIsTagValid(int &i, int l, Accessor &styler) {
while (i < l) {
if (styler.SafeGetCharAt(i) == '{') {
while (i < l) {
i++;
if (styler.SafeGetCharAt(i) == '}') {
return true;
} else if (!latexIsLetter(styler.SafeGetCharAt(i)) &&
styler.SafeGetCharAt(i)!='*') {
return false;
}
}
} else if (!latexIsBlank(styler.SafeGetCharAt(i))) {
return false;
}
i++;
}
return false;
}
static bool latexNextNotBlankIs(int i, Accessor &styler, char needle) {
char ch;
while (i < styler.Length()) {
ch = styler.SafeGetCharAt(i);
if (!latexIsBlankAndNL(ch) && ch != '*') {
if (ch == needle)
return true;
else
return false;
}
i++;
}
return false;
}
static bool latexLastWordIs(int start, Accessor &styler, const char *needle) {
unsigned int i = 0;
unsigned int l = static_cast<unsigned int>(strlen(needle));
int ini = start-l+1;
char s[32];
while (i < l && i < 31) {
s[i] = styler.SafeGetCharAt(ini + i);
i++;
}
s[i] = '\0';
return (strcmp(s, needle) == 0);
}
static bool latexLastWordIsMathEnv(int pos, Accessor &styler) {
int i, j;
char s[32];
const char *mathEnvs[] = { "align", "alignat", "flalign", "gather",
"multiline", "displaymath", "eqnarray", "equation" };
if (styler.SafeGetCharAt(pos) != '}') return false;
for (i = pos - 1; i >= 0; --i) {
if (styler.SafeGetCharAt(i) == '{') break;
if (pos - i >= 20) return false;
}
if (i < 0 || i == pos - 1) return false;
++i;
for (j = 0; i + j < pos; ++j)
s[j] = styler.SafeGetCharAt(i + j);
s[j] = '\0';
if (j == 0) return false;
if (s[j - 1] == '*') s[--j] = '\0';
for (i = 0; i < static_cast<int>(sizeof(mathEnvs) / sizeof(const char *)); ++i)
if (strcmp(s, mathEnvs[i]) == 0) return true;
return false;
}
static inline void latexStateReset(int &mode, int &state) {
switch (mode) {
case 1: state = SCE_L_MATH; break;
case 2: state = SCE_L_MATH2; break;
default: state = SCE_L_DEFAULT; break;
}
}
// There are cases not handled correctly, like $abcd\textrm{what is $x+y$}z+w$.
// But I think it's already good enough.
void SCI_METHOD LexerLaTeX::Lex(unsigned int startPos, int length, int initStyle, IDocument *pAccess) {
// startPos is assumed to be the first character of a line
Accessor styler(pAccess, &props);
styler.StartAt(startPos);
int mode = getMode(styler.GetLine(startPos) - 1);
int state = initStyle;
if (state == SCE_L_ERROR || state == SCE_L_SHORTCMD || state == SCE_L_SPECIAL) // should not happen
latexStateReset(mode, state);
char chNext = styler.SafeGetCharAt(startPos);
char chVerbatimDelim = '\0';
styler.StartSegment(startPos);
int lengthDoc = startPos + length;
for (int i = startPos; i < lengthDoc; i++) {
char ch = chNext;
chNext = styler.SafeGetCharAt(i + 1);
if (styler.IsLeadByte(ch)) {
i++;
chNext = styler.SafeGetCharAt(i + 1);
continue;
}
if (ch == '\r' || ch == '\n')
setMode(styler.GetLine(i), mode);
switch (state) {
case SCE_L_DEFAULT :
switch (ch) {
case '\\' :
styler.ColourTo(i - 1, state);
if (latexIsLetter(chNext)) {
state = SCE_L_COMMAND;
} else if (latexIsSpecial(chNext)) {
styler.ColourTo(i + 1, SCE_L_SPECIAL);
i++;
chNext = styler.SafeGetCharAt(i + 1);
} else if (chNext == '\r' || chNext == '\n') {
styler.ColourTo(i, SCE_L_ERROR);
} else if (IsASCII(chNext)) {
styler.ColourTo(i + 1, SCE_L_SHORTCMD);
if (chNext == '(') {
mode = 1;
state = SCE_L_MATH;
} else if (chNext == '[') {
mode = 2;
state = SCE_L_MATH2;
}
i++;
chNext = styler.SafeGetCharAt(i + 1);
}
break;
case '$' :
styler.ColourTo(i - 1, state);
if (chNext == '$') {
styler.ColourTo(i + 1, SCE_L_SHORTCMD);
mode = 2;
state = SCE_L_MATH2;
i++;
chNext = styler.SafeGetCharAt(i + 1);
} else {
styler.ColourTo(i, SCE_L_SHORTCMD);
mode = 1;
state = SCE_L_MATH;
}
break;
case '%' :
styler.ColourTo(i - 1, state);
state = SCE_L_COMMENT;
break;
}
break;
// These 3 will never be reached.
case SCE_L_ERROR:
case SCE_L_SPECIAL:
case SCE_L_SHORTCMD:
break;
case SCE_L_COMMAND :
if (!latexIsLetter(chNext)) {
styler.ColourTo(i, state);
if (latexNextNotBlankIs(i + 1, styler, '[' )) {
state = SCE_L_CMDOPT;
} else if (latexLastWordIs(i, styler, "\\begin")) {
state = SCE_L_TAG;
} else if (latexLastWordIs(i, styler, "\\end")) {
state = SCE_L_TAG2;
} else if (latexLastWordIs(i, styler, "\\verb") && chNext != '*' && chNext != ' ') {
chVerbatimDelim = chNext;
state = SCE_L_VERBATIM;
} else {
latexStateReset(mode, state);
}
}
break;
case SCE_L_CMDOPT :
if (ch == ']') {
styler.ColourTo(i, state);
latexStateReset(mode, state);
}
break;
case SCE_L_TAG :
if (latexIsTagValid(i, lengthDoc, styler)) {
styler.ColourTo(i, state);
latexStateReset(mode, state);
if (latexLastWordIs(i, styler, "{verbatim}")) {
state = SCE_L_VERBATIM;
} else if (latexLastWordIs(i, styler, "{comment}")) {
state = SCE_L_COMMENT2;
} else if (latexLastWordIs(i, styler, "{math}") && mode == 0) {
mode = 1;
state = SCE_L_MATH;
} else if (latexLastWordIsMathEnv(i, styler) && mode == 0) {
mode = 2;
state = SCE_L_MATH2;
}
} else {
styler.ColourTo(i, SCE_L_ERROR);
latexStateReset(mode, state);
ch = styler.SafeGetCharAt(i);
if (ch == '\r' || ch == '\n') setMode(styler.GetLine(i), mode);
}
chNext = styler.SafeGetCharAt(i+1);
break;
case SCE_L_TAG2 :
if (latexIsTagValid(i, lengthDoc, styler)) {
styler.ColourTo(i, state);
latexStateReset(mode, state);
} else {
styler.ColourTo(i, SCE_L_ERROR);
latexStateReset(mode, state);
ch = styler.SafeGetCharAt(i);
if (ch == '\r' || ch == '\n') setMode(styler.GetLine(i), mode);
}
chNext = styler.SafeGetCharAt(i+1);
break;
case SCE_L_MATH :
switch (ch) {
case '\\' :
styler.ColourTo(i - 1, state);
if (latexIsLetter(chNext)) {
int match = i + 3;
if (latexLastWordIs(match, styler, "\\end")) {
match++;
if (latexIsTagValid(match, lengthDoc, styler)) {
if (latexLastWordIs(match, styler, "{math}"))
mode = 0;
}
}
state = SCE_L_COMMAND;
} else if (latexIsSpecial(chNext)) {
styler.ColourTo(i + 1, SCE_L_SPECIAL);
i++;
chNext = styler.SafeGetCharAt(i + 1);
} else if (chNext == '\r' || chNext == '\n') {
styler.ColourTo(i, SCE_L_ERROR);
} else if (IsASCII(chNext)) {
if (chNext == ')') {
mode = 0;
state = SCE_L_DEFAULT;
}
styler.ColourTo(i + 1, SCE_L_SHORTCMD);
i++;
chNext = styler.SafeGetCharAt(i + 1);
}
break;
case '$' :
styler.ColourTo(i - 1, state);
styler.ColourTo(i, SCE_L_SHORTCMD);
mode = 0;
state = SCE_L_DEFAULT;
break;
case '%' :
styler.ColourTo(i - 1, state);
state = SCE_L_COMMENT;
break;
}
break;
case SCE_L_MATH2 :
switch (ch) {
case '\\' :
styler.ColourTo(i - 1, state);
if (latexIsLetter(chNext)) {
int match = i + 3;
if (latexLastWordIs(match, styler, "\\end")) {
match++;
if (latexIsTagValid(match, lengthDoc, styler)) {
if (latexLastWordIsMathEnv(match, styler))
mode = 0;
}
}
state = SCE_L_COMMAND;
} else if (latexIsSpecial(chNext)) {
styler.ColourTo(i + 1, SCE_L_SPECIAL);
i++;
chNext = styler.SafeGetCharAt(i + 1);
} else if (chNext == '\r' || chNext == '\n') {
styler.ColourTo(i, SCE_L_ERROR);
} else if (IsASCII(chNext)) {
if (chNext == ']') {
mode = 0;
state = SCE_L_DEFAULT;
}
styler.ColourTo(i + 1, SCE_L_SHORTCMD);
i++;
chNext = styler.SafeGetCharAt(i + 1);
}
break;
case '$' :
styler.ColourTo(i - 1, state);
if (chNext == '$') {
styler.ColourTo(i + 1, SCE_L_SHORTCMD);
i++;
chNext = styler.SafeGetCharAt(i + 1);
mode = 0;
state = SCE_L_DEFAULT;
} else { // This may not be an error, e.g. \begin{equation}\text{$a$}\end{equation}
styler.ColourTo(i, SCE_L_SHORTCMD);
}
break;
case '%' :
styler.ColourTo(i - 1, state);
state = SCE_L_COMMENT;
break;
}
break;
case SCE_L_COMMENT :
if (ch == '\r' || ch == '\n') {
styler.ColourTo(i - 1, state);
latexStateReset(mode, state);
}
break;
case SCE_L_COMMENT2 :
if (ch == '\\') {
int match = i + 3;
if (latexLastWordIs(match, styler, "\\end")) {
match++;
if (latexIsTagValid(match, lengthDoc, styler)) {
if (latexLastWordIs(match, styler, "{comment}")) {
styler.ColourTo(i - 1, state);
state = SCE_L_COMMAND;
}
}
}
}
break;
case SCE_L_VERBATIM :
if (ch == '\\') {
int match = i + 3;
if (latexLastWordIs(match, styler, "\\end")) {
match++;
if (latexIsTagValid(match, lengthDoc, styler)) {
if (latexLastWordIs(match, styler, "{verbatim}")) {
styler.ColourTo(i - 1, state);
state = SCE_L_COMMAND;
}
}
}
} else if (chNext == chVerbatimDelim) {
styler.ColourTo(i + 1, state);
latexStateReset(mode, state);
chVerbatimDelim = '\0';
i++;
chNext = styler.SafeGetCharAt(i + 1);
} else if (chVerbatimDelim != '\0' && (ch == '\n' || ch == '\r')) {
styler.ColourTo(i, SCE_L_ERROR);
latexStateReset(mode, state);
chVerbatimDelim = '\0';
}
break;
}
}
if (lengthDoc == styler.Length()) truncModes(styler.GetLine(lengthDoc - 1));
styler.ColourTo(lengthDoc - 1, state);
styler.Flush();
}
static int latexFoldSaveToInt(const latexFoldSave &save) {
int sum = 0;
for (int i = 0; i <= save.structLev; ++i)
sum += save.openBegins[i];
return ((sum + save.structLev + SC_FOLDLEVELBASE) & SC_FOLDLEVELNUMBERMASK);
}
// Change folding state while processing a line
// Return the level before the first relevant command
void SCI_METHOD LexerLaTeX::Fold(unsigned int startPos, int length, int, IDocument *pAccess) {
const char *structWords[7] = {"part", "chapter", "section", "subsection",
"subsubsection", "paragraph", "subparagraph"};
Accessor styler(pAccess, &props);
unsigned int endPos = startPos + length;
int curLine = styler.GetLine(startPos);
latexFoldSave save;
getSave(curLine - 1, save);
do {
char ch, buf[16];
int i, j, lev = -1;
bool needFold = false;
for (i = static_cast<int>(startPos); i < static_cast<int>(endPos); ++i) {
ch = styler.SafeGetCharAt(i);
if (ch == '\r' || ch == '\n') break;
if (ch != '\\' || styler.StyleAt(i) != SCE_L_COMMAND) continue;
for (j = 0; j < 15 && i + 1 < static_cast<int>(endPos); ++j, ++i) {
buf[j] = styler.SafeGetCharAt(i + 1);
if (!latexIsLetter(buf[j])) break;
}
buf[j] = '\0';
if (strcmp(buf, "begin") == 0) {
if (lev < 0) lev = latexFoldSaveToInt(save);
++save.openBegins[save.structLev];
needFold = true;
}
else if (strcmp(buf, "end") == 0) {
while (save.structLev > 0 && save.openBegins[save.structLev] == 0)
--save.structLev;
if (lev < 0) lev = latexFoldSaveToInt(save);
if (save.openBegins[save.structLev] > 0) --save.openBegins[save.structLev];
}
else {
for (j = 0; j < 7; ++j)
if (strcmp(buf, structWords[j]) == 0) break;
if (j >= 7) continue;
save.structLev = j; // level before the command
for (j = save.structLev + 1; j < 8; ++j) {
save.openBegins[save.structLev] += save.openBegins[j];
save.openBegins[j] = 0;
}
if (lev < 0) lev = latexFoldSaveToInt(save);
++save.structLev; // level after the command
needFold = true;
}
}
if (lev < 0) lev = latexFoldSaveToInt(save);
if (needFold) lev |= SC_FOLDLEVELHEADERFLAG;
styler.SetLevel(curLine, lev);
setSave(curLine, save);
++curLine;
startPos = styler.LineStart(curLine);
if (static_cast<int>(startPos) == styler.Length()) {
lev = latexFoldSaveToInt(save);
styler.SetLevel(curLine, lev);
setSave(curLine, save);
truncSaves(curLine);
}
} while (startPos < endPos);
styler.Flush();
}
static const char *const emptyWordListDesc[] = {
0
};
LexerModule lmLatex(SCLEX_LATEX, LexerLaTeX::LexerFactoryLaTeX, "latex", emptyWordListDesc);