From b58c02b6d04afcb906f57c0e631c1b478b8ff674 Mon Sep 17 00:00:00 2001
From: Elio Struyf <elio@struyfconsulting.be>
Date: Thu, 6 Feb 2025 10:20:31 +0100
Subject: [PATCH] Issue: Stripping underscore in default filename #914

---
 CHANGELOG.md                 | 12 ++++++++++++
 src/helpers/ArticleHelper.ts |  2 +-
 src/helpers/Sanitize.ts      | 14 ++++++++------
 3 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9d2debc1..603e0ae7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,17 @@
 # Change Log
 
+## [10.8.0] - 2025-02-xx
+
+### ✨ New features
+
+### 🎨 Enhancements
+
+### ⚡️ Optimizations
+
+### 🐞 Fixes
+
+- [#914](https://github.com/estruyf/vscode-front-matter/issues/914): Fix sanitizing of default filenames with an `_` in it
+
 ## [10.7.0] - 2024-12-31 - [Release notes](https://beta.frontmatter.codes/updates/v10.7.0)
 
 ### 🎨 Enhancements
diff --git a/src/helpers/ArticleHelper.ts b/src/helpers/ArticleHelper.ts
index 25334a09..e42e4251 100644
--- a/src/helpers/ArticleHelper.ts
+++ b/src/helpers/ArticleHelper.ts
@@ -572,7 +572,7 @@ export class ArticleHelper {
         await mkdirAsync(newFolder, { recursive: true });
         newFilePath = join(
           newFolder,
-          `${sanitize(contentType.defaultFileName ?? `index`)}.${
+          `${sanitize(contentType.defaultFileName || `index`, { isFileName: true })}.${
             fileExtension || contentType.fileType || fileType
           }`
         );
diff --git a/src/helpers/Sanitize.ts b/src/helpers/Sanitize.ts
index 088142b7..9162b944 100644
--- a/src/helpers/Sanitize.ts
+++ b/src/helpers/Sanitize.ts
@@ -1,17 +1,18 @@
-const illegalRe = /[/?<>\\:*|"!.,;{}[\]()_+=~`@#$%^&]/g;
+const illegalRe = (isFileName: boolean) =>
+  isFileName ? /[/?<>\\:*|"!.,;{}[\]()+=~`@#$%^&]/g : /[/?<>\\:*|"!.,;{}[\]()_+=~`@#$%^&]/g;
 // eslint-disable-next-line no-control-regex
 const controlRe = /[\x00-\x1f\x80-\x9f]/g;
 const reservedRe = /^\.+$/;
 const windowsReservedRe = /^(con|prn|aux|nul|com[0-9]|lpt[0-9])(\..*)?$/i;
 const windowsTrailingRe = /[. ]+$/;
 
-function sanitize(input: string, replacement: string) {
+function sanitize(input: string, replacement: string, isFileName?: boolean) {
   if (typeof input !== 'string') {
     throw new Error('Input must be string');
   }
 
   const sanitized = input
-    .replace(illegalRe, replacement)
+    .replace(illegalRe(isFileName || false), replacement)
     .replace(controlRe, replacement)
     .replace(reservedRe, replacement)
     .replace(windowsReservedRe, replacement)
@@ -19,11 +20,12 @@ function sanitize(input: string, replacement: string) {
   return sanitized;
 }
 
-export default function (input: string, options?: any) {
+export default function (input: string, options?: { replacement?: string; isFileName?: boolean }) {
   const replacement = (options && options.replacement) || '';
-  const output = sanitize(input, replacement);
+  const isFileName = options && options.isFileName;
+  const output = sanitize(input, replacement, isFileName);
   if (replacement === '') {
     return output;
   }
-  return sanitize(output, '');
+  return sanitize(output, '', isFileName);
 }