diff --git a/src/IterableCodeExtractor.php b/src/IterableCodeExtractor.php
index a0e9b148..7edc3f6a 100644
--- a/src/IterableCodeExtractor.php
+++ b/src/IterableCodeExtractor.php
@@ -234,6 +234,8 @@ function ( $file, $key, $iterator ) use ( $include, $exclude, $extensions ) {
 			$filtered_files[] = Utils\normalize_path( $file->getPathname() );
 		}
 
+		sort( $filtered_files, SORT_NATURAL | SORT_FLAG_CASE );
+
 		return $filtered_files;
 	}
 }
diff --git a/tests/IterableCodeExtractorTest.php b/tests/IterableCodeExtractorTest.php
index bdca27f3..d5d29e76 100644
--- a/tests/IterableCodeExtractorTest.php
+++ b/tests/IterableCodeExtractorTest.php
@@ -110,4 +110,17 @@ public function test_can_override_exclude_by_include() {
 		$expected = static::$base . 'foo/bar/excluded/ignored.js';
 		$this->assertContains( $expected, $result );
 	}
+
+	public function test_can_return_all_directory_files_sorted() {
+		$result   = IterableCodeExtractor::getFilesFromDirectory( self::$base, [ '*' ], [], [ 'php', 'js' ] );
+		$expected = array(
+			static::$base . 'baz/includes/should_be_included.js',
+			static::$base . 'foo-plugin/foo-plugin.php',
+			static::$base . 'foo/bar/excluded/ignored.js',
+			static::$base . 'foo/bar/foo/bar/foo/bar/deep_directory_also_included.php',
+			static::$base . 'foo/bar/foofoo/included.js',
+			static::$base . 'hoge/should_NOT_be_included.js',
+		);
+		$this->assertEquals( $expected, $result );
+	}
 }