Broke out the class name detection to make it easier to test

Author: gsherwood

autoload.php

@@ -160,27 +160,55 @@ public static function loadFile($path)
                 return self::$loadedClasses[$path];
             }
 
-            $classes    = get_declared_classes();
-            $interfaces = get_declared_interfaces();
-            $traits     = get_declared_traits();
+            $classesBeforeLoad = [
+                'classes'    => get_declared_classes(),
+                'interfaces' => get_declared_interfaces(),
+                'traits'     => get_declared_traits(),
+            ];
 
             include $path;
 
-            $className  = null;
-            $newClasses = array_reverse(array_diff(get_declared_classes(), $classes));
-            // Since PHP 7.4 get_declared_classes() does not guarantee any order. That
-            // implies that parent classes aren't the first any more, rendering the
-            // array_reverse() technique futile for the loop & break code that follows.
-            // So, additionally, let's try to reduce the list of candidates by removing all
-            // the classes known to be "parents". That way, at the end, only the "main"
-            // class just included with remain.
+            $classesAfterLoad = [
+                'classes'    => get_declared_classes(),
+                'interfaces' => get_declared_interfaces(),
+                'traits'     => get_declared_traits(),
+            ];
+
+            $className = self::determineLoadedClass($classesBeforeLoad, $classesAfterLoad);
+
+            self::$loadedClasses[$path]    = $className;
+            self::$loadedFiles[$className] = $path;
+            return self::$loadedClasses[$path];
+
+        }//end loadFile()
+
+
+        /**
+         * Determine which class was loaded based on the before and after lists of loaded classes.
+         *
+         * @param array $classesBeforeLoad The classes/interfaces/traits before the file was included.
+         * @param array $classesAfterLoad  The classes/interfaces/traits after the file was included.
+         *
+         * @return string The fully qualified name of the class in the loaded file.
+         */
+        public static function determineLoadedClass($classesBeforeLoad, $classesAfterLoad)
+        {
+            $className = null;
+
+            $newClasses = array_diff($classesAfterLoad['classes'], $classesBeforeLoad['classes']);
+
+            // Since PHP 7.4 get_declared_classes() does not guarantee any order, making
+            // it impossible to use order to determine which is the parent an which is the child.
+            // Let's reduce the list of candidates by removing all the classes known to be "parents".
+            // That way, at the end, only the "main" class just included will remain.
             $newClasses = array_reduce(
                 $newClasses,
                 function ($remaining, $current) {
                     return array_diff($remaining, class_parents($current));
                 },
                 $newClasses
             );
+
             foreach ($newClasses as $name) {
                 if (isset(self::$loadedFiles[$name]) === false) {
                     $className = $name;
@@ -189,7 +217,7 @@ function ($remaining, $current) {
             }
 
             if ($className === null) {
-                $newClasses = array_reverse(array_diff(get_declared_interfaces(), $interfaces));
+                $newClasses = array_reverse(array_diff($classesAfterLoad['interfaces'], $classesBeforeLoad['interfaces']));
                 foreach ($newClasses as $name) {
                     if (isset(self::$loadedFiles[$name]) === false) {
                         $className = $name;
@@ -199,7 +227,7 @@ function ($remaining, $current) {
             }
 
             if ($className === null) {
-                $newClasses = array_reverse(array_diff(get_declared_traits(), $traits));
+                $newClasses = array_reverse(array_diff($classesAfterLoad['traits'], $classesBeforeLoad['traits']));
                 foreach ($newClasses as $name) {
                     if (isset(self::$loadedFiles[$name]) === false) {
                         $className = $name;
@@ -208,11 +236,9 @@ function ($remaining, $current) {
                 }
             }
 
-            self::$loadedClasses[$path]    = $className;
-            self::$loadedFiles[$className] = $path;
-            return self::$loadedClasses[$path];
+            return $className;
 
-        }//end loadFile()
+        }//end determineLoadedClass()
 
 
         /**