From 55bb567e0f04644a7bad5f25e696983963d4dcf1 Mon Sep 17 00:00:00 2001
From: Felix Arntz <flixos90@git.wordpress.org>
Date: Fri, 14 Jul 2017 23:00:55 +0000
Subject: [PATCH] Multisite: Introduce a `self_admin_url` filter to adjust the
 URL to an administration panel.

Props j.hoffmann.
Fixes #37446.


git-svn-id: https://develop.svn.wordpress.org/trunk@41060 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/link-template.php     | 24 +++++++++---
 tests/phpunit/tests/link/adminUrl.php | 56 +++++++++++++++++++++++++++
 2 files changed, 74 insertions(+), 6 deletions(-)
 create mode 100644 tests/phpunit/tests/link/adminUrl.php

diff --git a/src/wp-includes/link-template.php b/src/wp-includes/link-template.php
index 4d3a37ca5d..9f8cb01e75 100644
--- a/src/wp-includes/link-template.php
+++ b/src/wp-includes/link-template.php
@@ -3397,12 +3397,24 @@ function user_admin_url( $path = '', $scheme = 'admin' ) {
  * @return string Admin URL link with optional path appended.
  */
 function self_admin_url( $path = '', $scheme = 'admin' ) {
-	if ( is_network_admin() )
-		return network_admin_url($path, $scheme);
-	elseif ( is_user_admin() )
-		return user_admin_url($path, $scheme);
-	else
-		return admin_url($path, $scheme);
+	if ( is_network_admin() ) {
+		$url = network_admin_url( $path, $scheme );
+	} elseif ( is_user_admin() ) {
+		$url = user_admin_url( $path, $scheme );
+	} else {
+		$url = admin_url( $path, $scheme );
+	}
+
+	/**
+	 * Filters the admin URL for the current site or network depending on context.
+	 *
+	 * @since 4.9.0
+	 *
+	 * @param string $url    The complete URL including scheme and path.
+	 * @param string $path   Path relative to the URL. Blank string if no path is specified.
+	 * @param string $scheme The scheme to use.
+	 */
+	return apply_filters( 'self_admin_url', $url, $path, $scheme );
 }
 
 /**
diff --git a/tests/phpunit/tests/link/adminUrl.php b/tests/phpunit/tests/link/adminUrl.php
new file mode 100644
index 0000000000..f736007a2e
--- /dev/null
+++ b/tests/phpunit/tests/link/adminUrl.php
@@ -0,0 +1,56 @@
+<?php
+
+/**
+ * @group link
+ */
+class Tests_Link_Admin extends WP_UnitTestCase {
+
+	/**
+	 * @ticket 37446
+	 */
+	public function test_self_admin_url() {
+		$this->assertSame( admin_url(), self_admin_url() );
+	}
+
+	/**
+	 * @ticket 37446
+	 */
+	public function test_self_admin_url_with_path() {
+		$path = 'options-general.php';
+
+		$this->assertSame( admin_url( $path ), self_admin_url( $path ) );
+	}
+
+	/**
+	 * @ticket 37446
+	 */
+	public function test_self_admin_url_with_path_and_scheme() {
+		$path = 'options-general.php';
+		$scheme = 'https';
+
+		$this->assertSame( admin_url( $path, $scheme ), self_admin_url( $path, $scheme ) );
+	}
+
+	/**
+	 * @ticket 37446
+	 */
+	public function test_self_admin_url_filtered() {
+		$path = 'options-general.php';
+		$scheme = 'https';
+
+		add_filter( 'self_admin_url', array( $this, 'filter_self_admin_url' ), 10, 3 );
+		$result = self_admin_url( $path, $scheme );
+		remove_filter( 'self_admin_url', array( $this, 'filter_self_admin_url' ), 10 );
+
+		$expected = home_url( '/global-admin/' . $path, $scheme );
+
+		$this->assertSame( $expected, $result );
+	}
+
+	/**
+	 * @ticket 37446
+	 */
+	public function filter_self_admin_url( $url, $path, $scheme ) {
+		return home_url( path_join( '/global-admin/', $path ), $scheme );
+	}
+}