Don't match partial roles in WP_User_Query.

Because 'role=ocean90' shouldn't match 'role=bocean901'.

Props bocean901, ocean90.
Fixes #22212.

git-svn-id: https://develop.svn.wordpress.org/trunk@35101 602fd350-edb4-49c9-b593-d223f7449a82

tests/phpunit/tests/user/query.php

@@ -955,6 +955,27 @@ class Tests_User_Query extends WP_UnitTestCase {
 		$this->assertEquals( 2, count( $users ) );
 	}
 
+	/**
+	 * @ticket 22212
+	 */
+	public function test_get_single_role_by_string_which_is_similar() {
+		$editors = $this->factory->user->create_many( 2, array(
+			'role' => 'editor',
+		) );
+
+		$another_editor = $this->factory->user->create( array(
+			'role' => 'another-editor',
+		) );
+
+		$users = get_users( array(
+			'role' => 'editor',
+			'fields' => 'ids',
+		) );
+
+		$this->assertEqualSets( $editors, $users );
+	}
+
+
 	/**
 	 * @ticket 22212
 	 */