marked-ln.patch

diff --git a/src/Lexer.js b/src/Lexer.js
adds linetracking to marked.js v4.3.0;
add data-ln="%d" to most tags, %d is the source markdown line
--- a/src/Lexer.js
+++ b/src/Lexer.js
@@ -52,4 +52,5 @@ function mangle(text) {
 export class Lexer {
   constructor(options) {
+    this.ln = 1;  // like most editors, start couting from 1
     this.tokens = [];
     this.tokens.links = Object.create(null);
@@ -128,4 +129,15 @@ export class Lexer {
   }
 
+  set_ln(token, ln = this.ln) {
+    // assigns ln (the current line numer) to the token,
+    // then bump this.ln by the number of newlines in the contents
+    //
+    // if ln is set, also assigns the line counter to a new value
+    // (usually a backup value from before a call into a subparser
+    //  which bumped the linecounter by a subset of the newlines)
+    token.ln = ln;
+    this.ln = ln + (token.raw.match(/\n/g) || []).length;
+  }
+
   /**
    * Lexing
@@ -140,7 +152,11 @@ export class Lexer {
     }
 
-    let token, lastToken, cutSrc, lastParagraphClipped;
+    let token, lastToken, cutSrc, lastParagraphClipped, ln;
 
     while (src) {
+      // this.ln will be bumped by recursive calls into this func;
+      // reset the count and rely on the outermost token's raw only
+      ln = this.ln;
+
       if (this.options.extensions
         && this.options.extensions.block
@@ -148,4 +164,5 @@ export class Lexer {
           if (token = extTokenizer.call({ lexer: this }, src, tokens)) {
             src = src.substring(token.raw.length);
+            this.set_ln(token, ln);
             tokens.push(token);
             return true;
@@ -159,4 +176,5 @@ export class Lexer {
       if (token = this.tokenizer.space(src)) {
         src = src.substring(token.raw.length);
+        this.set_ln(token, ln); // is \n if not type
         if (token.raw.length === 1 && tokens.length > 0) {
           // if there's a single \n as a spacer, it's terminating the last line,
@@ -172,4 +190,5 @@ export class Lexer {
       if (token = this.tokenizer.code(src)) {
         src = src.substring(token.raw.length);
+        this.set_ln(token, ln);
         lastToken = tokens[tokens.length - 1];
         // An indented code block cannot interrupt a paragraph.
@@ -187,4 +206,5 @@ export class Lexer {
       if (token = this.tokenizer.fences(src)) {
         src = src.substring(token.raw.length);
+        this.set_ln(token, ln);
         tokens.push(token);
         continue;
@@ -194,4 +214,5 @@ export class Lexer {
       if (token = this.tokenizer.heading(src)) {
         src = src.substring(token.raw.length);
+        this.set_ln(token, ln);
         tokens.push(token);
         continue;
@@ -201,4 +222,5 @@ export class Lexer {
       if (token = this.tokenizer.hr(src)) {
         src = src.substring(token.raw.length);
+        this.set_ln(token, ln);
         tokens.push(token);
         continue;
@@ -208,4 +230,5 @@ export class Lexer {
       if (token = this.tokenizer.blockquote(src)) {
         src = src.substring(token.raw.length);
+        this.set_ln(token, ln);
         tokens.push(token);
         continue;
@@ -215,4 +238,5 @@ export class Lexer {
       if (token = this.tokenizer.list(src)) {
         src = src.substring(token.raw.length);
+        this.set_ln(token, ln);
         tokens.push(token);
         continue;
@@ -222,4 +246,5 @@ export class Lexer {
       if (token = this.tokenizer.html(src)) {
         src = src.substring(token.raw.length);
+        this.set_ln(token, ln);
         tokens.push(token);
         continue;
@@ -229,4 +254,5 @@ export class Lexer {
       if (token = this.tokenizer.def(src)) {
         src = src.substring(token.raw.length);
+        this.set_ln(token, ln);
         lastToken = tokens[tokens.length - 1];
         if (lastToken && (lastToken.type === 'paragraph' || lastToken.type === 'text')) {
@@ -246,4 +272,5 @@ export class Lexer {
       if (token = this.tokenizer.table(src)) {
         src = src.substring(token.raw.length);
+        this.set_ln(token, ln);
         tokens.push(token);
         continue;
@@ -253,4 +280,5 @@ export class Lexer {
       if (token = this.tokenizer.lheading(src)) {
         src = src.substring(token.raw.length);
+        this.set_ln(token, ln);
         tokens.push(token);
         continue;
@@ -273,4 +301,5 @@ export class Lexer {
       }
       if (this.state.top && (token = this.tokenizer.paragraph(cutSrc))) {
+        this.set_ln(token, ln);
         lastToken = tokens[tokens.length - 1];
         if (lastParagraphClipped && lastToken.type === 'paragraph') {
@@ -290,4 +319,6 @@ export class Lexer {
       if (token = this.tokenizer.text(src)) {
         src = src.substring(token.raw.length);
+        this.set_ln(token, ln);
+        this.ln++;
         lastToken = tokens[tokens.length - 1];
         if (lastToken && lastToken.type === 'text') {
@@ -367,4 +398,5 @@ export class Lexer {
           if (token = extTokenizer.call({ lexer: this }, src, tokens)) {
             src = src.substring(token.raw.length);
+            this.ln = token.ln || this.ln;
             tokens.push(token);
             return true;
@@ -432,4 +464,6 @@ export class Lexer {
       if (token = this.tokenizer.br(src)) {
         src = src.substring(token.raw.length);
+        // no need to reset (no more blockTokens anyways)
+        token.ln = this.ln++;
         tokens.push(token);
         continue;
@@ -474,4 +508,5 @@ export class Lexer {
       if (token = this.tokenizer.inlineText(cutSrc, smartypants)) {
         src = src.substring(token.raw.length);
+        this.ln = token.ln || this.ln;
         if (token.raw.slice(-1) !== '_') { // Track prevChar before string of ____ started
           prevChar = token.raw.slice(-1);
diff --git a/src/Parser.js b/src/Parser.js
index a22a2bc..884ad66 100644
--- a/src/Parser.js
+++ b/src/Parser.js
@@ -18,4 +18,5 @@ export class Parser {
     this.textRenderer = new TextRenderer();
     this.slugger = new Slugger();
+    this.ln = 0; // error indicator; should always be set >=1 from tokens
   }
 
@@ -64,4 +65,8 @@ export class Parser {
     for (i = 0; i < l; i++) {
       token = tokens[i];
+      // take line-numbers from tokens whenever possible
+      // and update the renderer's html attribute with the new value
+      this.ln = token.ln || this.ln;
+      this.renderer.tag_ln(this.ln);
 
       // Run any renderer extensions
@@ -124,7 +129,10 @@ export class Parser {
             }
 
-            body += this.renderer.tablerow(cell);
+            // the +2 is to skip the table header
+            body += this.renderer.tag_ln(token.ln + j + 2).tablerow(cell);
           }
-          out += this.renderer.table(header, body);
+          // the html attribute is now at the end of the table,
+          // reset it before writing the <table> tag now
+          out += this.renderer.tag_ln(token.ln).table(header, body);
           continue;
         }
@@ -167,8 +175,12 @@ export class Parser {
 
             itemBody += this.parse(item.tokens, loose);
-            body += this.renderer.listitem(itemBody, task, checked);
+            // similar to tables, writing contents before the <ul> tag
+            // so update the tag attribute as we go
+            // (assuming all list entries got tagged with a source-line, probably safe w)
+            body += this.renderer.tag_ln((item.tokens[0] || token).ln).listitem(itemBody, task, checked);
           }
 
-          out += this.renderer.list(body, ordered, start);
+          // then reset to the <ul>'s correct line number and write it
+          out += this.renderer.tag_ln(token.ln).list(body, ordered, start);
           continue;
         }
@@ -179,5 +191,6 @@ export class Parser {
         }
         case 'paragraph': {
-          out += this.renderer.paragraph(this.parseInline(token.tokens));
+          let t = this.parseInline(token.tokens);
+          out += this.renderer.tag_ln(token.ln).paragraph(t);
           continue;
         }
@@ -221,4 +234,7 @@ export class Parser {
       token = tokens[i];
 
+      // another thing that only affects <br/> and other inlines
+      this.ln = token.ln || this.ln;
+
       // Run any renderer extensions
       if (this.options.extensions && this.options.extensions.renderers && this.options.extensions.renderers[token.type]) {
diff --git a/src/Renderer.js b/src/Renderer.js
--- a/src/Renderer.js
+++ b/src/Renderer.js
@@ -11,6 +11,12 @@ export class Renderer {
   constructor(options) {
     this.options = options || defaults;
+    this.ln = "";
   }
 
+  tag_ln(n) {
+    this.ln = ` data-ln="${n}"`;
+    return this;
+  };
+
   code(code, infostring, escaped) {
     const lang = (infostring || '').match(/\S*/)[0];
@@ -26,10 +32,10 @@ export class Renderer {
 
     if (!lang) {
-      return '<pre><code>'
+      return '<pre' + this.ln + '><code>'
         + (escaped ? code : escape(code, true))
         + '</code></pre>\n';
     }
 
-    return '<pre><code class="'
+    return '<pre' + this.ln + '><code class="'
       + this.options.langPrefix
       + escape(lang)
@@ -43,5 +49,5 @@ export class Renderer {
    */
   blockquote(quote) {
-    return `<blockquote>\n${quote}</blockquote>\n`;
+    return `<blockquote${this.ln}>\n${quote}</blockquote>\n`;
   }
 
@@ -59,9 +65,9 @@ export class Renderer {
     if (this.options.headerIds) {
       const id = this.options.headerPrefix + slugger.slug(raw);
-      return `<h${level} id="${id}">${text}</h${level}>\n`;
+      return `<h${level}${this.ln} id="${id}">${text}</h${level}>\n`;
     }
 
     // ignore IDs
-    return `<h${level}>${text}</h${level}>\n`;
+    return `<h${level}${this.ln}>${text}</h${level}>\n`;
   }
 
@@ -80,5 +86,5 @@ export class Renderer {
    */
   listitem(text) {
-    return `<li>${text}</li>\n`;
+    return `<li${this.ln}>${text}</li>\n`;
   }
 
@@ -95,5 +101,5 @@ export class Renderer {
    */
   paragraph(text) {
-    return `<p>${text}</p>\n`;
+    return `<p${this.ln}>${text}</p>\n`;
   }
 
@@ -117,5 +123,5 @@ export class Renderer {
    */
   tablerow(content) {
-    return `<tr>\n${content}</tr>\n`;
+    return `<tr${this.ln}>\n${content}</tr>\n`;
   }
 
@@ -151,5 +157,5 @@ export class Renderer {
 
   br() {
-    return this.options.xhtml ? '<br/>' : '<br>';
+    return this.options.xhtml ? `<br${this.ln}/>` : `<br${this.ln}>`;
   }
 
@@ -190,5 +196,5 @@ export class Renderer {
     }
 
-    let out = `<img src="${href}" alt="${text}"`;
+    let out = `<img${this.ln} src="${href}" alt="${text}"`;
     if (title) {
       out += ` title="${title}"`;
diff --git a/src/Tokenizer.js b/src/Tokenizer.js
--- a/src/Tokenizer.js
+++ b/src/Tokenizer.js
@@ -333,4 +333,7 @@ export class Tokenizer {
       const l = list.items.length;
 
+      // each nested list gets +1 ahead; this hack makes every listgroup -1 but atleast it doesn't get infinitely bad
+      this.lexer.ln--;
+
       // Item child tokens handled here at end because we needed to have the final item to trim it first
       for (i = 0; i < l; i++) {