fix: preserve special characters in search queries (#3441)

Co-authored-by: claude[bot] <41898282+claude[bot]@users.noreply.github.com>
Co-authored-by: Chris Bongers <rebelchris@users.noreply.github.com>

Author: rebelchris

__tests__/bookmarks.ts

@@ -1069,6 +1069,46 @@ describe('query searchBookmarksSuggestions', () => {
     const res = await client.query(QUERY('p1'));
     expect(res.data).toMatchSnapshot();
   });
+
+  it('should handle special characters in search (C++)', async () => {
+    loggedUser = '1';
+    await con.getRepository(ArticlePost).save({
+      id: 'cpp-post',
+      title: 'Learn C++ programming',
+      shortId: 'cpp',
+      url: 'http://cpp.com',
+      sourceId: 'a',
+      visible: true,
+    });
+    await con.getRepository(Bookmark).save({
+      userId: loggedUser,
+      postId: 'cpp-post',
+      createdAt: now,
+    });
+    const res = await client.query(QUERY('c++'));
+    expect(res.data.searchBookmarksSuggestions.query).toBe('c++');
+    expect(res.data.searchBookmarksSuggestions.hits.length).toBeGreaterThan(0);
+  });
+
+  it('should handle special characters in search (C#)', async () => {
+    loggedUser = '1';
+    await con.getRepository(ArticlePost).save({
+      id: 'csharp-post',
+      title: 'Learn C# programming',
+      shortId: 'csharp',
+      url: 'http://csharp.com',
+      sourceId: 'a',
+      visible: true,
+    });
+    await con.getRepository(Bookmark).save({
+      userId: loggedUser,
+      postId: 'csharp-post',
+      createdAt: now,
+    });
+    const res = await client.query(QUERY('c#'));
+    expect(res.data.searchBookmarksSuggestions.query).toBe('c#');
+    expect(res.data.searchBookmarksSuggestions.hits.length).toBeGreaterThan(0);
+  });
 });
 
 describe('query searchBookmarks', () => {

__tests__/users.ts

@@ -3440,6 +3440,50 @@ describe('query searchReadingHistorySuggestions', () => {
     const res = await client.query(QUERY('p1'));
     expect(res.data).toMatchSnapshot();
   });
+
+  it('should handle special characters in search (C++)', async () => {
+    loggedUser = '1';
+    await con.getRepository(ArticlePost).save({
+      id: 'cpp-post',
+      title: 'Learn C++ programming',
+      shortId: 'cpp',
+      url: 'http://cpp.com',
+      sourceId: 'a',
+      visible: true,
+    });
+    await con.getRepository(View).save({
+      userId: loggedUser,
+      timestamp: now,
+      postId: 'cpp-post',
+    });
+    const res = await client.query(QUERY('c++'));
+    expect(res.data.searchReadingHistorySuggestions.query).toBe('c++');
+    expect(
+      res.data.searchReadingHistorySuggestions.hits.length,
+    ).toBeGreaterThan(0);
+  });
+
+  it('should handle special characters in search (C#)', async () => {
+    loggedUser = '1';
+    await con.getRepository(ArticlePost).save({
+      id: 'csharp-post',
+      title: 'Learn C# programming',
+      shortId: 'csharp',
+      url: 'http://csharp.com',
+      sourceId: 'a',
+      visible: true,
+    });
+    await con.getRepository(View).save({
+      userId: loggedUser,
+      timestamp: now,
+      postId: 'csharp-post',
+    });
+    const res = await client.query(QUERY('c#'));
+    expect(res.data.searchReadingHistorySuggestions.query).toBe('c#');
+    expect(
+      res.data.searchReadingHistorySuggestions.hits.length,
+    ).toBeGreaterThan(0);
+  });
 });
 
 describe('query search reading history', () => {

src/schema/common.ts

@@ -190,8 +190,23 @@ export interface PageGenerator<
 export const getSearchQuery = (param: string): string =>
   `SELECT to_tsquery('english', ${param}) AS query`;
 
-export const processSearchQuery = (query: string): string =>
-  query.trim().split(' ').join(' & ') + ':*';
+export const processSearchQuery = (query: string): string => {
+  const trimmed = query.trim();
+
+  // Check if query contains special characters that should be preserved
+  // Common programming language patterns: c#, c++, f#, .net, node.js, etc.
+  const hasSpecialChars = /[#+.\-]/.test(trimmed);
+
+  if (hasSpecialChars) {
+    // For queries with special characters, use phrase search to preserve them
+    // Replace single quotes with double single quotes to escape them
+    const escaped = trimmed.replace(/'/g, "''");
+    return `'${escaped}':*`;
+  }
+
+  // For regular queries, use the original AND logic with prefix matching
+  return trimmed.split(' ').join(' & ') + ':*';
+};
 
 export const mimirOffsetGenerator = <
   TReturn extends { id: string },