Category Search Fails When Search Term Contains an Ampersand Followed by a Space, Admin Page/Post Editor

[chhapoliya]

Bug Report:

Product: WordPress
Version: 7.1.2, 7.1.3 and others
Component: Posts / Categories / Editor
Issue Type: Bug

Summary

When adding or editing a post in the WordPress admin dashboard, searching for a category whose name contains an ampersand (&) followed by a space does not return the expected search result.

For example, a category named “Tour & Travel” cannot be found when searching for Tour & (including the trailing space).

## Steps to Reproduce

1. Create a category named Tour & Travel.
2. Navigate to Posts → Add New or edit an existing post.
3. Open the Categories panel in the post editor.
4. Search for Tour & , including the space after the ampersand.
5. Observe the search results.

## Expected Behavior

The category “Tour & Travel” should appear in the search results when searching for Tour & , since the entered text matches the beginning of the category name.

## Actual Behavior

The category does not appear in the search results when the search term contains an ampersand followed by a space.

## Additional Information

• The issue occurs in the WordPress admin post editor while adding or editing a post.
• The affected category contains an ampersand followed by a space in its name.
• The issue appears to involve partial category-name matching when special characters and whitespace are present.

Suggested investigation: Check how the category search filters and processes search terms containing ampersands and trailing whitespace, including any differences in query tokenization or sanitization.

## Impact

This behavior makes it harder for users to find and assign categories containing ampersands when searching by partial category name.

## Environment

• WordPress version: 7.1.2 and others
• Editor: [Gutenberg / Classic Editor — specify which applies]
• Browser: Tested in Chrome & Safari
• Active plugins: No, Tested in PlayGround

[chhapoliya]

The search with space after ampersand shows no result, in categories

[sainathpoojary]

Reproduction Report

Environment

• WordPress: 7.2-alpha-63166-src
• Subdirectory: No
• PHP: 8.3.33
• Server: nginx/1.31.6
• Database: mysqli (Server: 9.7.2 / Client: mysqlnd 8.3.33)
• Browser: Chrome 154.0.0.0
• OS: macOS
• Theme: Twenty Twenty-Five 1.5
• MU Plugins: None
• Plugins: Test Reports 1.3.1

Steps taken

1. Navigated to Posts → Categories and created a category named Tour & Travel.
2. Created additional dummy categories (at least 8–10 total) so the block editor displays the category search input field.
3. Navigated to Posts → Add New.
4. Expanded the Categories panel in the editor settings sidebar.
5. In the Search Categories input, typed Tour & (including the ampersand and trailing space).
6. Bug occurs: The Tour & Travel category disappears from the list, displaying "0 results found."

Expected behavior

The category Tour & Travel should remain visible in the filtered results, since Tour & matches the beginning of the category name.

Screenshots

Taxonomy: Allow searching terms containing ampersands and HTML entities

---

Description

When term names are saved in WordPress, _wp_specialchars() encodes ampersands as & into wp_terms.name (priority 30 on pre_term_name in default-filters.php).

Prior to this change, WP_Term_Query::get_search_sql() created search clauses using only the raw $search value:

((t.name LIKE '%search%') OR (t.slug LIKE '%search%'))

Because MySQL does not equate raw '&' with '&', searching for terms containing ampersands (such as "Tour & ", "Tour & Travel", or "& Travel") failed completely on both wp-admin/edit-tags.php and any queries powered by WP_Term_Query / get_terms( array( 'search' => ... ) ).

Solution

In WP_Term_Query::get_search_sql():

1. Check if the search term contains characters requiring HTML entity encoding (_wp_specialchars( $search, ENT_COMPAT, 'UTF-8', true )).
2. Decode pre-encoded entities (wp_specialchars_decode()) to support searches submitted with entities.
3. If distinct variants are found, expand the search query with an OR condition across both forms:

   (((t.name LIKE '%Tour & %') OR (t.slug LIKE '%Tour & %')) OR ((t.name LIKE '%Tour & %') OR (t.slug LIKE '%Tour & %')))
   

4. If no special characters are detected, a single clause is generated, preserving identical execution and indexing performance for standard terms.

Testing Instructions

1. Create a category named Tour & Travel.
2. Search for Tour & (with a trailing space) on Posts -> Categories (wp-admin/edit-tags.php?taxonomy=category).
3. Verify that Tour & Travel is found in the search results table.
4. Run PHPUnit test suite:

   vendor/bin/phpunit tests/phpunit/tests/term/getSearchSql.php
      vendor/bin/phpunit -c tests/phpunit/multisite.xml tests/phpunit/tests/term/getSearchSql.php
   

5. Run PHPCS:

   vendor/bin/phpcs src/wp-includes/class-wp-term-query.php tests/phpunit/tests/term/getSearchSql.php
   

[therssoftware]

### Test & Review Report

Ticket: https://core.trac.wordpress.org/ticket/66279
PR: ​https://github.com/WordPress/wordpress-develop/pull/14187
Component: Taxonomy
Status: Has PR / Awaiting Review

---

#### Environment

• WordPress: 7.2-alpha-63166-src (trunk) & 7.1.3
• PHP: 8.4.1
• Server: macOS Darwin (arm64) / Nginx
• Database: MySQL 8.0.35
• PHPUnit: 9.6.37
• PHPCS: 3.13.5 (WordPress-Core)
• Browser: Google Chrome

---

#### Summary of the Issue & Proposed Changes

##### 1. The Issue
When term names are inserted/updated in WordPress, _wp_specialchars() is applied to pre_term_name at priority 30 in default-filters.php, encoding ampersands as & in wp_terms.name (e.g. "Tour & Travel" is stored as "Tour & Travel").

In WP_Term_Query::get_search_sql() (src/wp-includes/class-wp-term-query.php), search clauses were generated using only the raw $search string:
`sql
((t.name LIKE '%search%') OR (t.slug LIKE '%search%'))
`
Because MySQL does not equate '& ' with '& ', any search term containing an ampersand followed by a space or word (e.g. "Tour & ", "Tour & Travel", or "& Travel") fails to return results on:

• Admin Categories list table (wp-admin/edit-tags.php?taxonomy=category)
• Block Editor post categories filter
• REST API queries (/wp/v2/categories?search=...) and get_terms( array( 'search' => ... ) )

##### 2. Proposed Changes

• WP_Term_Query::get_search_sql() now detects special characters and generates search clauses for both raw and HTML-entity-encoded forms (_wp_specialchars( $search, ENT_COMPAT, 'UTF-8', true )).
• Pre-encoded entities are decoded using wp_specialchars_decode() to also support queries submitted with entities.
• When multiple variants exist, clauses are combined with OR: `sql (((t.name LIKE '%Tour & %') OR (t.slug LIKE '%Tour & %')) OR ((t.name LIKE '%Tour & %') OR (t.slug LIKE '%Tour & %'))) `
• When no entities/special characters are present, a single clause is generated without overhead, ensuring zero regressions for standard queries.

---

#### Verification & Test Results

##### 1. Bug Reproduction (without patch)

• In the Block Editor, creating category "Tour & Travel" and typing "Tour & " in the Categories search box returned 0 categories found.
• In wp-admin/edit-tags.php?taxonomy=category, searching for "Tour & " in tag-search-input returned No categories found.
• In PHPUnit: `php get_terms( array( 'taxonomy' => 'category', 'search' => 'Tour & ', 'fields' => 'ids' ) ); ` Returned empty array().

##### 2. After Applying Patch

• Searching "Tour & " or "Tour & Travel" in the Block Editor instantly displays "Tour & Travel", allowing selection and saving.
• Searching "Tour & " on wp-admin/edit-tags.php?taxonomy=category displays "Tour & Travel" in the table.

##### 3. Dedicated PHPUnit Tests
Added dedicated test file tests/phpunit/tests/term/getSearchSql.php:

• Tests all 8 variations of ampersand queries ('Tour & ', 'Tour & T', 'Tour & Travel', '& Travel', '&', 'Tour & ', 'Tour & Travel', '& Travel').
• Tests standard searches without entities ('bur' matching 'Burrito' and 'Wilbur').
• Validates SQL structure via Reflection (single clause for standard terms, composite OR for entity variations).

Single Site:
`bash
vendor/bin/phpunit tests/phpunit/tests/term/getSearchSql.php
`
`text
.......... 10 / 10 (100%)
OK (10 tests, 31 assertions)
`

Multisite:
`bash
vendor/bin/phpunit -c tests/phpunit/multisite.xml tests/phpunit/tests/term/getSearchSql.php
`
`text
.......... 10 / 10 (100%)
OK (10 tests, 31 assertions)
`

Regression Suite:
`bash
vendor/bin/phpunit tests/phpunit/tests/term/getTerms.php tests/phpunit/tests/term/query.php
`
`text
OK (114 tests, 378 assertions)
`

##### 4. PHPCS Standards Verification
`bash
vendor/bin/phpcs src/wp-includes/class-wp-term-query.php tests/phpunit/tests/term/getSearchSql.php
`
`text
.. 2 / 2 (100%)
Time: 160ms; Memory: 8MB
`
0 errors, 0 warnings.

• Followed global variable placement (global $wpdb; placed immediately before first use).