Implement trailing slash for no-dot paths

[szepeviktor]

Adds a filter to mod_rewrite_rules to enforce trailing slashes for URLs without dots.

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Summary by cubic

Enforces trailing slashes for paths without dots by injecting an .htaccess rule via the mod_rewrite_rules filter. Requests missing a trailing slash (and with no dot) are 301-redirected to the slash version for canonical URLs and consistent routing.

^{Written for commit 934401c. Summary will update on new commits.}

[Copilot]

Pull request overview

This PR adds a new MU plugin that enforces trailing slashes on URLs without file extensions by filtering WordPress's mod_rewrite rules. The plugin inserts Apache RewriteRule directives that redirect URLs ending without a slash (and not containing a dot) to their trailing-slash equivalents with a 301 redirect.

Changes:

• Added new MU plugin _core-auto-trailing-slash.php that filters mod_rewrite_rules to inject rewrite rules for trailing slash enforcement
• Implements logic to handle both cases where "RewriteEngine On" exists or doesn't exist in the rules
• Uses priority 20 for the filter to control execution order

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[Copilot]

There's no check to prevent duplicate insertion of the rewrite rule if this filter is called multiple times or if the rule already exists in the rules string. Consider checking if the insertion content already exists in $rules before adding it again, or storing a flag to track if the insertion has already been performed.

[cubic-dev-ai]

1 issue found across 1 file

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="mu-plugins/_core-auto-trailing-slash.php">

<violation number="1" location="mu-plugins/_core-auto-trailing-slash.php:14">
P2: Using a 301 redirect here can change non‑GET requests (POST/PUT) to GET and drop the body. That will break API or form submissions sent to no‑dot paths. Prefer a method-preserving redirect (308) or limit the rule to GET/HEAD requests.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P2: Using a 301 redirect here can change non‑GET requests (POST/PUT) to GET and drop the body. That will break API or form submissions sent to no‑dot paths. Prefer a method-preserving redirect (308) or limit the rule to GET/HEAD requests.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At mu-plugins/_core-auto-trailing-slash.php, line 14:

<comment>Using a 301 redirect here can change non‑GET requests (POST/PUT) to GET and drop the body. That will break API or form submissions sent to no‑dot paths. Prefer a method-preserving redirect (308) or limit the rule to GET/HEAD requests.</comment>

<file context>
@@ -0,0 +1,25 @@
+        $insertion = <<<HTACCESS
+# Add trailing slash if doesn't end with / and doesn't contain a dot
+RewriteCond %{REQUEST_URI} !(\.|/$)
+RewriteRule ^(.+)$ /$1/ [R=301,L]
+
+HTACCESS;
</file context>