From aab5833166dbfdf9e9be54af2f75634fae88c413 Mon Sep 17 00:00:00 2001
From: David Anson <david@dlaa.me>
Date: Tue, 25 Nov 2025 16:20:19 -0800
Subject: [PATCH] wip

---
 lib/md013.mjs | 39 ++++++++++++---------------------------
 1 file changed, 12 insertions(+), 27 deletions(-)

diff --git a/lib/md013.mjs b/lib/md013.mjs
index 0d1b24ea..1bb21aed 100644
--- a/lib/md013.mjs
+++ b/lib/md013.mjs
@@ -4,10 +4,8 @@ import { addErrorDetailIf } from "../helpers/helpers.cjs";
 import { filterByTypesCached, getReferenceLinkImageData } from "./cache.mjs";
 import { addRangeToSet, getDescendantsByType } from "../helpers/micromark-helpers.cjs";
 
-const longLineRePrefix = "^.{";
-const longLineRePostfixRelaxed = "}.*\\s.*$";
-const longLineRePostfixStrict = "}.+$";
-const sternModeRe = /^(?:[#>\s]*\s)?\S*$/;
+// Regular expression for a line that is not wrappable
+const notWrappableRe = /^(?:[#>\s]*\s)?\S*$/;
 
 /** @typedef {import("micromark-extension-gfm-autolink-literal")} */
 /** @typedef {import("micromark-extension-gfm-table")} */
@@ -20,20 +18,10 @@ export default {
   "parser": "micromark",
   "function": function MD013(params, onError) {
     const lineLength = Number(params.config.line_length || 80);
-    const headingLineLength =
-      Number(params.config.heading_line_length || lineLength);
-    const codeLineLength =
-      Number(params.config.code_block_line_length || lineLength);
+    const headingLineLength = Number(params.config.heading_line_length || lineLength);
+    const codeLineLength = Number(params.config.code_block_line_length || lineLength);
     const strict = !!params.config.strict;
     const stern = !!params.config.stern;
-    const longLineRePostfix =
-      (strict || stern) ? longLineRePostfixStrict : longLineRePostfixRelaxed;
-    const longLineRe =
-      new RegExp(longLineRePrefix + lineLength + longLineRePostfix);
-    const longHeadingLineRe =
-      new RegExp(longLineRePrefix + headingLineLength + longLineRePostfix);
-    const longCodeLineRe =
-      new RegExp(longLineRePrefix + codeLineLength + longLineRePostfix);
     const codeBlocks = params.config.code_blocks;
     const includeCodeBlocks = (codeBlocks === undefined) ? true : !!codeBlocks;
     const tables = params.config.tables;
@@ -75,28 +63,25 @@ export default {
       const isHeading = headingLineNumbers.has(lineNumber);
       const inCode = codeBlockLineNumbers.has(lineNumber);
       const inTable = tableLineNumbers.has(lineNumber);
-      const length = inCode ?
-        codeLineLength :
-        (isHeading ? headingLineLength : lineLength);
-      const lengthRe = inCode ?
-        longCodeLineRe :
-        (isHeading ? longHeadingLineRe : longLineRe);
-      if ((includeCodeBlocks || !inCode) &&
+      const maxLength = inCode ? codeLineLength : (isHeading ? headingLineLength : lineLength);
+      const text = (strict || stern) ? line : line.replace(/\S*$/u, "");
+      if ((maxLength > 0) &&
+          (includeCodeBlocks || !inCode) &&
           (includeTables || !inTable) &&
           (includeHeadings || !isHeading) &&
           !definitionLineIndices.has(lineIndex) &&
           (strict ||
-           (!(stern && sternModeRe.test(line)) &&
+           (!(stern && notWrappableRe.test(line)) &&
             !linkOnlyLineNumbers.has(lineNumber))) &&
-          lengthRe.test(line)) {
+          (text.length > maxLength)) {
         addErrorDetailIf(
           onError,
           lineNumber,
-          length,
+          maxLength,
           line.length,
           undefined,
           undefined,
-          [ length + 1, line.length - length ]
+          [ maxLength + 1, line.length - maxLength ]
         );
       }
     }