Backslashes are not always escaped when String.Contains is translated to LIKE

[doominator42]

Steps to reproduce

queryable.Where(e => e.StringProperty.Contains("\\"))

The issue

The escaping is wrong when using String.Contains("\\"). It gets translated to e.StringProperty LIKE '%\\%' (escaped only once, but should have been escaped twice for LIKE). Using String.Contains("\\%") correctly translates to e.StringProperty LIKE '%\\\\\\%%'.

By looking at the translator, it seems only strings with wildcard characters are escaped. https://github.com/PomeloFoundation/Pomelo.EntityFrameworkCore.MySql/blob/b02dd67febafcb9dc08b803175cf3039d8127804/src/EFCore.MySql/Query/ExpressionTranslators/Internal/MySqlStringComparisonMethodTranslator.cs#L479

\ must be escaped too. There is the same issue for String.StartsWith and String.EndsWith.

Further technical details

MySQL version: 10.9.8-MariaDB-1:10.9.8+maria~ubu2204 Operating system: Arch Linux, Alpine Linux 3.20, Fedora 40 Pomelo.EntityFrameworkCore.MySql version: 8.0.2 Microsoft.AspNetCore.App version: 8.0.8