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notepad-plus-plus/lexilla/lexers/LexR.cxx

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9.4 KiB

// Scintilla source code edit control
/** @file LexR.cxx
** Lexer for R, S, SPlus Statistics Program (Heavily derived from CPP Lexer).
**
**/
// Copyright 1998-2002 by Neil Hodgson <neilh@scintilla.org>
// The License.txt file describes the conditions under which this software may be distributed.
#include <cassert>
#include <cctype>
#include <string>
#include <string_view>
#include "ILexer.h"
#include "Scintilla.h"
#include "SciLexer.h"
#include "WordList.h"
#include "LexAccessor.h"
#include "Accessor.h"
#include "StyleContext.h"
#include "CharacterSet.h"
#include "LexerModule.h"
using namespace Lexilla;
namespace {
inline bool IsAWordChar(int ch) noexcept {
return (ch < 0x80) && (isalnum(ch) || ch == '.' || ch == '_');
}
inline bool IsAWordStart(int ch) noexcept {
return (ch < 0x80) && (isalnum(ch) || ch == '_');
}
constexpr bool IsAnOperator(int ch) noexcept {
// '.' left out as it is used to make up numbers
if (ch == '-' || ch == '+' || ch == '!' || ch == '~' ||
ch == '?' || ch == ':' || ch == '*' || ch == '/' ||
ch == '^' || ch == '<' || ch == '>' || ch == '=' ||
ch == '&' || ch == '|' || ch == '$' || ch == '(' ||
ch == ')' || ch == '}' || ch == '{' || ch == '[' ||
ch == ']')
return true;
return false;
}
constexpr bool IsOctalOrHex(int ch, bool hex) noexcept {
return IsAnOctalDigit(ch) || (hex && IsAHeXDigit(ch));
}
// https://search.r-project.org/R/refmans/base/html/Quotes.html
struct EscapeSequence {
int outerState = SCE_R_DEFAULT;
int digitsLeft = 0;
bool hex = false;
bool brace = false;
// highlight any character as escape sequence, unrecognized escape sequence is syntax error.
void resetEscapeState(int state, int chNext) noexcept {
outerState = state;
digitsLeft = 1;
hex = true;
brace = false;
if (chNext == 'x') {
digitsLeft = 3;
} else if (chNext == 'u') {
digitsLeft = 5;
} else if (chNext == 'U') {
digitsLeft = 9;
} else if (IsAnOctalDigit(chNext)) {
digitsLeft = 3;
hex = false;
}
}
bool atEscapeEnd(int ch) noexcept {
--digitsLeft;
return digitsLeft <= 0 || !IsOctalOrHex(ch, hex);
}
};
int CheckRawString(LexAccessor &styler, Sci_Position pos, int &dashCount) {
dashCount = 0;
while (true) {
const char ch = styler.SafeGetCharAt(pos++);
switch (ch) {
case '-':
++dashCount;
break;
case '(':
return ')';
case '[':
return ']';
case '{':
return '}';
default:
dashCount = 0;
return 0;
}
}
}
void ColouriseRDoc(Sci_PositionU startPos, Sci_Position length, int initStyle, WordList *keywordlists[],
Accessor &styler) {
const WordList &keywords = *keywordlists[0];
const WordList &keywords2 = *keywordlists[1];
const WordList &keywords3 = *keywordlists[2];
// state for raw string
int matchingDelimiter = 0;
int dashCount = 0;
// property lexer.r.escape.sequence
// Set to 1 to enable highlighting of escape sequences in strings.
const bool escapeSequence = styler.GetPropertyInt("lexer.r.escape.sequence", 0) != 0;
EscapeSequence escapeSeq;
StyleContext sc(startPos, length, initStyle, styler);
if (sc.currentLine > 0) {
const int lineState = styler.GetLineState(sc.currentLine - 1);
matchingDelimiter = lineState & 0xff;
dashCount = lineState >> 8;
}
for (; sc.More(); sc.Forward()) {
// Determine if the current state should terminate.
switch (sc.state) {
case SCE_R_OPERATOR:
sc.SetState(SCE_R_DEFAULT);
break;
case SCE_R_NUMBER:
// https://cran.r-project.org/doc/manuals/r-release/R-lang.html#Literal-constants
if (AnyOf(sc.ch, 'e', 'E', 'p', 'P') && (IsADigit(sc.chNext) || sc.chNext == '+' || sc.chNext == '-')) {
sc.Forward(); // exponent part
} else if (!(IsAHeXDigit(sc.ch) || (sc.ch == '.' && IsADigit(sc.chNext)))) {
if (AnyOf(sc.ch, 'L', 'i')) {
sc.Forward(); // integer and complex qualifier
}
sc.SetState(SCE_R_DEFAULT);
}
break;
case SCE_R_IDENTIFIER:
if (!IsAWordChar(sc.ch)) {
char s[100];
sc.GetCurrent(s, sizeof(s));
if (keywords.InList(s)) {
sc.ChangeState(SCE_R_KWORD);
} else if (keywords2.InList(s)) {
sc.ChangeState(SCE_R_BASEKWORD);
} else if (keywords3.InList(s)) {
sc.ChangeState(SCE_R_OTHERKWORD);
}
sc.SetState(SCE_R_DEFAULT);
}
break;
case SCE_R_COMMENT:
if (sc.MatchLineEnd()) {
sc.SetState(SCE_R_DEFAULT);
}
break;
case SCE_R_STRING:
case SCE_R_STRING2:
case SCE_R_BACKTICKS:
if (sc.ch == '\\') {
if (escapeSequence) {
escapeSeq.resetEscapeState(sc.state, sc.chNext);
sc.SetState(SCE_R_ESCAPESEQUENCE);
sc.Forward();
if (sc.chNext == '{' && AnyOf(sc.ch, 'u', 'U')) {
escapeSeq.brace = true;
sc.Forward();
} else if (sc.MatchLineEnd()) {
// don't highlight line ending as escape sequence:
// escapeSeq.outerState is lost when editing on next line.
sc.SetState(escapeSeq.outerState);
}
} else {
sc.Forward(); // Skip all characters after the backslash
}
} else if ((sc.state == SCE_R_STRING && sc.ch == '\"')
|| (sc.state == SCE_R_STRING2 && sc.ch == '\'')
|| (sc.state == SCE_R_BACKTICKS && sc.ch == '`')) {
sc.ForwardSetState(SCE_R_DEFAULT);
}
break;
case SCE_R_ESCAPESEQUENCE:
if (escapeSeq.atEscapeEnd(sc.ch)) {
if (escapeSeq.brace && sc.ch == '}') {
sc.Forward();
}
sc.SetState(escapeSeq.outerState);
continue;
}
break;
case SCE_R_RAWSTRING:
case SCE_R_RAWSTRING2:
while (sc.ch == matchingDelimiter) {
sc.Forward();
int count = dashCount;
while (count != 0 && sc.ch == '-') {
--count;
sc.Forward();
}
if (count == 0 && sc.ch == ((sc.state == SCE_R_RAWSTRING) ? '\"' : '\'')) {
matchingDelimiter = 0;
dashCount = 0;
sc.ForwardSetState(SCE_R_DEFAULT);
break;
}
}
break;
case SCE_R_INFIX:
if (sc.ch == '%') {
sc.ForwardSetState(SCE_R_DEFAULT);
} else if (sc.atLineEnd) {
sc.ChangeState(SCE_R_INFIXEOL);
}
break;
case SCE_R_INFIXEOL:
if (sc.atLineStart) {
sc.SetState(SCE_R_DEFAULT);
}
break;
}
// Determine if a new state should be entered.
if (sc.state == SCE_R_DEFAULT) {
if (IsADigit(sc.ch) || (sc.ch == '.' && IsADigit(sc.chNext))) {
sc.SetState(SCE_R_NUMBER);
if (sc.ch == '0' && AnyOf(sc.chNext, 'x', 'X')) {
sc.Forward();
}
} else if (AnyOf(sc.ch, 'r', 'R') && AnyOf(sc.chNext, '\"', '\'')) {
const int chNext = sc.chNext;
matchingDelimiter = CheckRawString(styler, sc.currentPos + 2, dashCount);
if (matchingDelimiter) {
sc.SetState((chNext == '\"') ? SCE_R_RAWSTRING : SCE_R_RAWSTRING2);
sc.Forward(dashCount + 2);
} else {
// syntax error
sc.SetState(SCE_R_IDENTIFIER);
sc.ForwardSetState((chNext == '\"') ? SCE_R_STRING : SCE_R_STRING2);
}
} else if (IsAWordStart(sc.ch) ) {
sc.SetState(SCE_R_IDENTIFIER);
} else if (sc.Match('#')) {
sc.SetState(SCE_R_COMMENT);
} else if (sc.ch == '\"') {
sc.SetState(SCE_R_STRING);
} else if (sc.ch == '%') {
sc.SetState(SCE_R_INFIX);
} else if (sc.ch == '\'') {
sc.SetState(SCE_R_STRING2);
} else if (sc.ch == '`') {
sc.SetState(SCE_R_BACKTICKS);
} else if (IsAnOperator(sc.ch)) {
sc.SetState(SCE_R_OPERATOR);
}
}
if (sc.atLineEnd) {
const int lineState = matchingDelimiter | (dashCount << 8);
styler.SetLineState(sc.currentLine, lineState);
}
}
sc.Complete();
}
// Store both the current line's fold level and the next lines in the
// level store to make it easy to pick up with each increment
// and to make it possible to fiddle the current level for "} else {".
void FoldRDoc(Sci_PositionU startPos, Sci_Position length, int, WordList *[],
Accessor &styler) {
const bool foldCompact = styler.GetPropertyInt("fold.compact", 1) != 0;
const bool foldAtElse = styler.GetPropertyInt("fold.at.else", 0) != 0;
const Sci_PositionU endPos = startPos + length;
int visibleChars = 0;
Sci_Position lineCurrent = styler.GetLine(startPos);
int levelCurrent = SC_FOLDLEVELBASE;
if (lineCurrent > 0)
levelCurrent = styler.LevelAt(lineCurrent-1) >> 16;
int levelMinCurrent = levelCurrent;
int levelNext = levelCurrent;
char chNext = styler[startPos];
int styleNext = styler.StyleAt(startPos);
for (Sci_PositionU i = startPos; i < endPos; i++) {
const char ch = chNext;
chNext = styler.SafeGetCharAt(i + 1);
const int style = styleNext;
styleNext = styler.StyleAt(i + 1);
const bool atEOL = (ch == '\r' && chNext != '\n') || (ch == '\n');
if (style == SCE_R_OPERATOR) {
if (ch == '{') {
// Measure the minimum before a '{' to allow
// folding on "} else {"
if (levelMinCurrent > levelNext) {
levelMinCurrent = levelNext;
}
levelNext++;
} else if (ch == '}') {
levelNext--;
}
}
if (atEOL) {
int levelUse = levelCurrent;
if (foldAtElse) {
levelUse = levelMinCurrent;
}
int lev = levelUse | levelNext << 16;
if (visibleChars == 0 && foldCompact)
lev |= SC_FOLDLEVELWHITEFLAG;
if (levelUse < levelNext)
lev |= SC_FOLDLEVELHEADERFLAG;
if (lev != styler.LevelAt(lineCurrent)) {
styler.SetLevel(lineCurrent, lev);
}
lineCurrent++;
levelCurrent = levelNext;
levelMinCurrent = levelCurrent;
visibleChars = 0;
}
if (!isspacechar(ch))
visibleChars++;
}
}
const char * const RWordLists[] = {
"Language Keywords",
"Base / Default package function",
"Other Package Functions",
"Unused",
"Unused",
nullptr,
};
}
LexerModule lmR(SCLEX_R, ColouriseRDoc, "r", FoldRDoc, RWordLists);