You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
484 lines
18 KiB
484 lines
18 KiB
/******************************************************************
|
|
* LexMarkdown.cxx
|
|
*
|
|
* A simple Markdown lexer for scintilla.
|
|
*
|
|
* Includes highlighting for some extra features from the
|
|
* Pandoc implementation; strikeout, using '#.' as a default
|
|
* ordered list item marker, and delimited code blocks.
|
|
*
|
|
* Limitations:
|
|
*
|
|
* Standard indented code blocks are not highlighted at all,
|
|
* as it would conflict with other indentation schemes. Use
|
|
* delimited code blocks for blanket highlighting of an
|
|
* entire code block. Embedded HTML is not highlighted either.
|
|
* Blanket HTML highlighting has issues, because some Markdown
|
|
* implementations allow Markdown markup inside of the HTML. Also,
|
|
* there is a following blank line issue that can't be ignored,
|
|
* explained in the next paragraph. Embedded HTML and code
|
|
* blocks would be better supported with language specific
|
|
* highlighting.
|
|
*
|
|
* The highlighting aims to accurately reflect correct syntax,
|
|
* but a few restrictions are relaxed. Delimited code blocks are
|
|
* highlighted, even if the line following the code block is not blank.
|
|
* Requiring a blank line after a block, breaks the highlighting
|
|
* in certain cases, because of the way Scintilla ends up calling
|
|
* the lexer.
|
|
*
|
|
* Written by Jon Strait - jstrait@moonloop.net
|
|
*
|
|
* 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 <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 {
|
|
|
|
constexpr bool IsNewline(const int ch) {
|
|
// sc.GetRelative(i) returns '\0' if out of range
|
|
return (ch == '\n' || ch == '\r' || ch == '\0');
|
|
}
|
|
|
|
}
|
|
|
|
// True if can follow ch down to the end with possibly trailing whitespace
|
|
// Does not set the state SCE_MARKDOWN_LINE_BEGIN as to allow further processing
|
|
static bool FollowToLineEnd(const int ch, const int state, const Sci_PositionU endPos, StyleContext &sc) {
|
|
Sci_Position i = 0;
|
|
while (sc.GetRelative(++i) == ch)
|
|
;
|
|
// Skip over whitespace
|
|
while (IsASpaceOrTab(sc.GetRelative(i)) && sc.currentPos + i < endPos)
|
|
++i;
|
|
if (IsNewline(sc.GetRelative(i)) || sc.currentPos + i == endPos) {
|
|
sc.SetState(state);
|
|
sc.Forward(i);
|
|
return true;
|
|
}
|
|
else return false;
|
|
}
|
|
|
|
// Set the state on text section from current to length characters,
|
|
// then set the rest until the newline to default, except for any characters matching token
|
|
static void SetStateAndZoom(const int state, const Sci_Position length, const int token, StyleContext &sc) {
|
|
sc.SetState(state);
|
|
sc.Forward(length);
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
sc.Forward();
|
|
bool started = false;
|
|
while (sc.More() && !IsNewline(sc.ch)) {
|
|
if (sc.ch == token && !started) {
|
|
sc.SetState(state);
|
|
started = true;
|
|
}
|
|
else if (sc.ch != token) {
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
started = false;
|
|
}
|
|
sc.Forward();
|
|
}
|
|
sc.SetState(SCE_MARKDOWN_LINE_BEGIN);
|
|
}
|
|
|
|
// Does the previous line have more than spaces and tabs?
|
|
static bool HasPrevLineContent(StyleContext &sc) {
|
|
Sci_Position i = 0;
|
|
// Go back to the previous newline
|
|
while ((--i + (Sci_Position)sc.currentPos) >= 0 && !IsNewline(sc.GetRelative(i)))
|
|
;
|
|
while ((--i + (Sci_Position)sc.currentPos) >= 0) {
|
|
const int ch = sc.GetRelative(i);
|
|
if (ch == '\n')
|
|
break;
|
|
if (!((ch == '\r' || IsASpaceOrTab(ch))))
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static bool AtTermStart(StyleContext &sc) {
|
|
return sc.currentPos == 0 || sc.chPrev == 0 || isspacechar(sc.chPrev);
|
|
}
|
|
|
|
static bool IsCompleteStyleRegion(StyleContext &sc, const char *token) {
|
|
bool found = false;
|
|
const size_t start = strlen(token);
|
|
Sci_Position i = static_cast<Sci_Position>(start);
|
|
while (!IsNewline(sc.GetRelative(i))) {
|
|
// make sure an empty pair of single-char tokens doesn't match
|
|
// with a longer token: {*}{*} != {**}
|
|
if (sc.GetRelative(i) == *token && sc.GetRelative(i - 1) != *token) {
|
|
found = start > 1U ? sc.GetRelative(i + 1) == token[1] : true;
|
|
break;
|
|
}
|
|
i++;
|
|
}
|
|
return AtTermStart(sc) && found;
|
|
}
|
|
|
|
static bool IsValidHrule(const Sci_PositionU endPos, StyleContext &sc) {
|
|
int count = 1;
|
|
Sci_Position i = 0;
|
|
for (;;) {
|
|
++i;
|
|
int c = sc.GetRelative(i);
|
|
if (c == sc.ch)
|
|
++count;
|
|
// hit a terminating character
|
|
else if (!IsASpaceOrTab(c) || sc.currentPos + i == endPos) {
|
|
// Are we a valid HRULE
|
|
if ((IsNewline(c) || sc.currentPos + i == endPos) &&
|
|
count >= 3 && !HasPrevLineContent(sc)) {
|
|
sc.SetState(SCE_MARKDOWN_HRULE);
|
|
sc.Forward(i);
|
|
sc.SetState(SCE_MARKDOWN_LINE_BEGIN);
|
|
return true;
|
|
}
|
|
else {
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
return false;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static void ColorizeMarkdownDoc(Sci_PositionU startPos, Sci_Position length, int initStyle,
|
|
WordList **, Accessor &styler) {
|
|
Sci_PositionU endPos = startPos + length;
|
|
int precharCount = 0;
|
|
bool isLinkNameDetecting = false;
|
|
// Don't advance on a new loop iteration and retry at the same position.
|
|
// Useful in the corner case of having to start at the beginning file position
|
|
// in the default state.
|
|
bool freezeCursor = false;
|
|
|
|
// property lexer.markdown.header.eolfill
|
|
// Set to 1 to highlight all ATX header text.
|
|
bool headerEOLFill = styler.GetPropertyInt("lexer.markdown.header.eolfill", 0) == 1;
|
|
|
|
StyleContext sc(startPos, static_cast<Sci_PositionU>(length), initStyle, styler);
|
|
|
|
while (sc.More()) {
|
|
// Skip past escaped characters
|
|
if (sc.ch == '\\') {
|
|
sc.Forward();
|
|
continue;
|
|
}
|
|
|
|
// A blockquotes resets the line semantics
|
|
if (sc.state == SCE_MARKDOWN_BLOCKQUOTE)
|
|
sc.SetState(SCE_MARKDOWN_LINE_BEGIN);
|
|
|
|
// Conditional state-based actions
|
|
if (sc.state == SCE_MARKDOWN_CODE2) {
|
|
if (sc.Match("``")) {
|
|
const int closingSpan = (sc.GetRelative(2) == '`') ? 3 : 2;
|
|
sc.Forward(closingSpan);
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
}
|
|
else if (sc.state == SCE_MARKDOWN_CODE) {
|
|
if (sc.ch == '`' && sc.chPrev != ' ')
|
|
sc.ForwardSetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
/* De-activated because it gets in the way of other valid indentation
|
|
* schemes, for example multiple paragraphs inside a list item.
|
|
// Code block
|
|
else if (sc.state == SCE_MARKDOWN_CODEBK) {
|
|
bool d = true;
|
|
if (IsNewline(sc.ch)) {
|
|
if (sc.chNext != '\t') {
|
|
for (int c = 1; c < 5; ++c) {
|
|
if (sc.GetRelative(c) != ' ')
|
|
d = false;
|
|
}
|
|
}
|
|
}
|
|
else if (sc.atLineStart) {
|
|
if (sc.ch != '\t' ) {
|
|
for (int i = 0; i < 4; ++i) {
|
|
if (sc.GetRelative(i) != ' ')
|
|
d = false;
|
|
}
|
|
}
|
|
}
|
|
if (!d)
|
|
sc.SetState(SCE_MARKDOWN_LINE_BEGIN);
|
|
}
|
|
*/
|
|
// Strong
|
|
else if (sc.state == SCE_MARKDOWN_STRONG1) {
|
|
if ((sc.Match("**") && sc.chPrev != ' ') || IsNewline(sc.GetRelative(2))) {
|
|
sc.Forward(2);
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
}
|
|
else if (sc.state == SCE_MARKDOWN_STRONG2) {
|
|
if ((sc.Match("__") && sc.chPrev != ' ') || IsNewline(sc.GetRelative(2))) {
|
|
sc.Forward(2);
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
}
|
|
// Emphasis
|
|
else if (sc.state == SCE_MARKDOWN_EM1) {
|
|
if ((sc.ch == '*' && sc.chPrev != ' ') || IsNewline(sc.chNext))
|
|
sc.ForwardSetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
else if (sc.state == SCE_MARKDOWN_EM2) {
|
|
if ((sc.ch == '_' && sc.chPrev != ' ') || IsNewline(sc.chNext))
|
|
sc.ForwardSetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
else if (sc.state == SCE_MARKDOWN_CODEBK) {
|
|
if (sc.atLineStart && sc.Match("~~~")) {
|
|
Sci_Position i = 1;
|
|
while (!IsNewline(sc.GetRelative(i)) && sc.currentPos + i < endPos)
|
|
i++;
|
|
sc.Forward(i);
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
}
|
|
else if (sc.state == SCE_MARKDOWN_STRIKEOUT) {
|
|
if ((sc.Match("~~") && sc.chPrev != ' ') || IsNewline(sc.GetRelative(2))) {
|
|
sc.Forward(2);
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
}
|
|
else if (sc.state == SCE_MARKDOWN_LINE_BEGIN) {
|
|
// Header
|
|
if (sc.Match("######")) {
|
|
if (headerEOLFill)
|
|
sc.SetState(SCE_MARKDOWN_HEADER6);
|
|
else
|
|
SetStateAndZoom(SCE_MARKDOWN_HEADER6, 6, '#', sc);
|
|
}
|
|
else if (sc.Match("#####")) {
|
|
if (headerEOLFill)
|
|
sc.SetState(SCE_MARKDOWN_HEADER5);
|
|
else
|
|
SetStateAndZoom(SCE_MARKDOWN_HEADER5, 5, '#', sc);
|
|
}
|
|
else if (sc.Match("####")) {
|
|
if (headerEOLFill)
|
|
sc.SetState(SCE_MARKDOWN_HEADER4);
|
|
else
|
|
SetStateAndZoom(SCE_MARKDOWN_HEADER4, 4, '#', sc);
|
|
}
|
|
else if (sc.Match("###")) {
|
|
if (headerEOLFill)
|
|
sc.SetState(SCE_MARKDOWN_HEADER3);
|
|
else
|
|
SetStateAndZoom(SCE_MARKDOWN_HEADER3, 3, '#', sc);
|
|
}
|
|
else if (sc.Match("##")) {
|
|
if (headerEOLFill)
|
|
sc.SetState(SCE_MARKDOWN_HEADER2);
|
|
else
|
|
SetStateAndZoom(SCE_MARKDOWN_HEADER2, 2, '#', sc);
|
|
}
|
|
else if (sc.Match("#")) {
|
|
// Catch the special case of an unordered list
|
|
if (sc.chNext == '.' && IsASpaceOrTab(sc.GetRelative(2))) {
|
|
precharCount = 0;
|
|
sc.SetState(SCE_MARKDOWN_PRECHAR);
|
|
}
|
|
else if (headerEOLFill) {
|
|
sc.SetState(SCE_MARKDOWN_HEADER1);
|
|
}
|
|
else
|
|
SetStateAndZoom(SCE_MARKDOWN_HEADER1, 1, '#', sc);
|
|
}
|
|
// Code block
|
|
else if (sc.Match("~~~")) {
|
|
if (!HasPrevLineContent(sc))
|
|
sc.SetState(SCE_MARKDOWN_CODEBK);
|
|
else
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
else if (sc.ch == '=') {
|
|
if (HasPrevLineContent(sc) && FollowToLineEnd('=', SCE_MARKDOWN_HEADER1, endPos, sc)) {
|
|
if (!headerEOLFill)
|
|
sc.SetState(SCE_MARKDOWN_LINE_BEGIN);
|
|
}
|
|
else
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
else if (sc.ch == '-') {
|
|
if (HasPrevLineContent(sc) && FollowToLineEnd('-', SCE_MARKDOWN_HEADER2, endPos, sc)) {
|
|
if (!headerEOLFill)
|
|
sc.SetState(SCE_MARKDOWN_LINE_BEGIN);
|
|
}
|
|
else {
|
|
precharCount = 0;
|
|
sc.SetState(SCE_MARKDOWN_PRECHAR);
|
|
}
|
|
}
|
|
else if (IsNewline(sc.ch))
|
|
sc.SetState(SCE_MARKDOWN_LINE_BEGIN);
|
|
else {
|
|
precharCount = 0;
|
|
sc.SetState(SCE_MARKDOWN_PRECHAR);
|
|
}
|
|
}
|
|
|
|
// The header lasts until the newline
|
|
else if (sc.state == SCE_MARKDOWN_HEADER1 || sc.state == SCE_MARKDOWN_HEADER2 ||
|
|
sc.state == SCE_MARKDOWN_HEADER3 || sc.state == SCE_MARKDOWN_HEADER4 ||
|
|
sc.state == SCE_MARKDOWN_HEADER5 || sc.state == SCE_MARKDOWN_HEADER6) {
|
|
if (headerEOLFill) {
|
|
if (sc.atLineStart) {
|
|
sc.SetState(SCE_MARKDOWN_LINE_BEGIN);
|
|
freezeCursor = true;
|
|
}
|
|
}
|
|
else if (IsNewline(sc.ch))
|
|
sc.SetState(SCE_MARKDOWN_LINE_BEGIN);
|
|
}
|
|
|
|
// New state only within the initial whitespace
|
|
if (sc.state == SCE_MARKDOWN_PRECHAR) {
|
|
// Blockquote
|
|
if (sc.ch == '>' && precharCount < 5)
|
|
sc.SetState(SCE_MARKDOWN_BLOCKQUOTE);
|
|
/*
|
|
// Begin of code block
|
|
else if (!HasPrevLineContent(sc) && (sc.chPrev == '\t' || precharCount >= 4))
|
|
sc.SetState(SCE_MARKDOWN_CODEBK);
|
|
*/
|
|
// HRule - Total of three or more hyphens, asterisks, or underscores
|
|
// on a line by themselves
|
|
else if ((sc.ch == '-' || sc.ch == '*' || sc.ch == '_') && IsValidHrule(endPos, sc))
|
|
;
|
|
// Unordered list
|
|
else if ((sc.ch == '-' || sc.ch == '*' || sc.ch == '+') && IsASpaceOrTab(sc.chNext)) {
|
|
sc.SetState(SCE_MARKDOWN_ULIST_ITEM);
|
|
sc.ForwardSetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
// Ordered list
|
|
else if (IsADigit(sc.ch)) {
|
|
int digitCount = 0;
|
|
while (IsADigit(sc.GetRelative(++digitCount)))
|
|
;
|
|
if (sc.GetRelative(digitCount) == '.' &&
|
|
IsASpaceOrTab(sc.GetRelative(digitCount + 1))) {
|
|
sc.SetState(SCE_MARKDOWN_OLIST_ITEM);
|
|
sc.Forward(digitCount + 1);
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
}
|
|
// Alternate Ordered list
|
|
else if (sc.ch == '#' && sc.chNext == '.' && IsASpaceOrTab(sc.GetRelative(2))) {
|
|
sc.SetState(SCE_MARKDOWN_OLIST_ITEM);
|
|
sc.Forward(2);
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
else if (sc.ch != ' ' || precharCount > 2)
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
else
|
|
++precharCount;
|
|
}
|
|
|
|
// Any link
|
|
if (sc.state == SCE_MARKDOWN_LINK) {
|
|
if (sc.Match("](") && sc.GetRelative(-1) != '\\') {
|
|
sc.Forward(2);
|
|
isLinkNameDetecting = true;
|
|
}
|
|
else if (sc.Match("]:") && sc.GetRelative(-1) != '\\') {
|
|
sc.Forward(2);
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
else if (!isLinkNameDetecting && sc.ch == ']' && sc.GetRelative(-1) != '\\') {
|
|
sc.Forward();
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
}
|
|
else if (isLinkNameDetecting && sc.ch == ')' && sc.GetRelative(-1) != '\\') {
|
|
sc.Forward();
|
|
sc.SetState(SCE_MARKDOWN_DEFAULT);
|
|
isLinkNameDetecting = false;
|
|
}
|
|
}
|
|
|
|
// New state anywhere in doc
|
|
if (sc.state == SCE_MARKDOWN_DEFAULT) {
|
|
if (sc.atLineStart && sc.ch == '#') {
|
|
sc.SetState(SCE_MARKDOWN_LINE_BEGIN);
|
|
freezeCursor = true;
|
|
}
|
|
// Links and Images
|
|
if (sc.Match("![")) {
|
|
sc.SetState(SCE_MARKDOWN_LINK);
|
|
sc.Forward(1);
|
|
}
|
|
else if (sc.ch == '[' && sc.GetRelative(-1) != '\\') {
|
|
sc.SetState(SCE_MARKDOWN_LINK);
|
|
}
|
|
// Code - also a special case for alternate inside spacing
|
|
else if (sc.Match("``") && sc.GetRelative(3) != ' ' && AtTermStart(sc)) {
|
|
const int openingSpan = (sc.GetRelative(2) == '`') ? 2 : 1;
|
|
sc.SetState(SCE_MARKDOWN_CODE2);
|
|
sc.Forward(openingSpan);
|
|
}
|
|
else if (sc.ch == '`' && sc.chNext != ' ' && IsCompleteStyleRegion(sc, "`")) {
|
|
sc.SetState(SCE_MARKDOWN_CODE);
|
|
}
|
|
// Strong
|
|
else if (sc.Match("**") && sc.GetRelative(2) != ' ' && IsCompleteStyleRegion(sc, "**")) {
|
|
sc.SetState(SCE_MARKDOWN_STRONG1);
|
|
sc.Forward();
|
|
}
|
|
else if (sc.Match("__") && sc.GetRelative(2) != ' ' && IsCompleteStyleRegion(sc, "__")) {
|
|
sc.SetState(SCE_MARKDOWN_STRONG2);
|
|
sc.Forward();
|
|
}
|
|
// Emphasis
|
|
else if (sc.ch == '*' && sc.chNext != ' ' && IsCompleteStyleRegion(sc, "*")) {
|
|
sc.SetState(SCE_MARKDOWN_EM1);
|
|
}
|
|
else if (sc.ch == '_' && sc.chNext != ' ' && IsCompleteStyleRegion(sc, "_")) {
|
|
sc.SetState(SCE_MARKDOWN_EM2);
|
|
}
|
|
// Strikeout
|
|
else if (sc.Match("~~") && !(sc.GetRelative(2) == '~' || sc.GetRelative(2) == ' ') &&
|
|
IsCompleteStyleRegion(sc, "~~")) {
|
|
sc.SetState(SCE_MARKDOWN_STRIKEOUT);
|
|
sc.Forward();
|
|
}
|
|
// Beginning of line
|
|
else if (IsNewline(sc.ch)) {
|
|
sc.SetState(SCE_MARKDOWN_LINE_BEGIN);
|
|
}
|
|
}
|
|
// Advance if not holding back the cursor for this iteration.
|
|
if (!freezeCursor)
|
|
sc.Forward();
|
|
freezeCursor = false;
|
|
}
|
|
sc.Complete();
|
|
}
|
|
|
|
LexerModule lmMarkdown(SCLEX_MARKDOWN, ColorizeMarkdownDoc, "markdown");
|