fix: escape backslash in the middle of sentence (nhn#2588)

* test: add test for escape baskslash * fix: escape backslash in the middle of sentence
ahamelers · Jul 5, 2022 · 729efbc · 729efbc
1 parent 746b02b
commit 729efbc
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Showing 2 changed files with 23 additions and 6 deletions.
diff --git a/src/__test__/unit/convertor.spec.ts b/src/__test__/unit/convertor.spec.ts
@@ -1098,4 +1098,15 @@ describe('Convertor', () => {
 
     expect(result).toBe(`<strong>"test"</strong>a`);
   });
+
+  it('should escape the backslash, which is a plain chracter in the middle of a sentence', () => {
+    const markdown = source`
+      backslash \\in the middle of a sentence
+      `;
+    const expected = source`
+      backslash \\\\in the middle of a sentence
+      `;
+
+    assertConverting(markdown, expected);
+  });
 });
diff --git a/src/utils/common.ts b/src/utils/common.ts
@@ -12,7 +12,8 @@ const reEscapeHTML = /<([a-zA-Z_][a-zA-Z0-9\-._]*)(\s|[^\\>])*\/?>|<(\/)([a-zA-Z
 const reEscapeBackSlash = /\\[!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~\\]/g;
 const reEscapePairedChars = /[*_~`]/g;
 const reMdImageSyntax = /!\[.*\]\(.*\)/g;
-const reEscapedCharInLinkSyntax = /[[\]]/g; //
+const reEscapedCharInLinkSyntax = /[[\]]/g;
+const reEscapeBackSlashInSentence = /(?:^|[^\\])\\(?!\\)/g;
 
 const XMLSPECIAL = '[&<>"]';
 const reXmlSpecial = new RegExp(XMLSPECIAL, 'g');
@@ -118,22 +119,27 @@ export function escapeTextForLink(text: string) {
 }
 
 export function escape(text: string) {
-  const replacer = (matched: string) => `\\${matched}`;
+  const aheadReplacer = (matched: string) => `\\${matched}`;
+  const behindReplacer = (matched: string) => `${matched}\\`;
 
   let escapedText = text.replace(reSpaceMoreThanOne, ' ');
 
   if (reEscapeBackSlash.test(escapedText)) {
-    escapedText = escapedText.replace(reEscapeBackSlash, replacer);
+    escapedText = escapedText.replace(reEscapeBackSlash, aheadReplacer);
   }
 
-  escapedText = escapedText.replace(reEscapePairedChars, replacer);
+  if (reEscapeBackSlashInSentence.test(escapedText)) {
+    escapedText = escapedText.replace(reEscapeBackSlashInSentence, behindReplacer);
+  }
+
+  escapedText = escapedText.replace(reEscapePairedChars, aheadReplacer);
 
   if (reEscapeHTML.test(escapedText)) {
-    escapedText = escapedText.replace(reEscapeHTML, replacer);
+    escapedText = escapedText.replace(reEscapeHTML, aheadReplacer);
   }
 
   if (isNeedEscapeText(escapedText)) {
-    escapedText = escapedText.replace(reEscapeChars, replacer);
+    escapedText = escapedText.replace(reEscapeChars, aheadReplacer);
   }
 
   return escapedText;