error handler and correct return for polyfill require

Author: Le0Developer

CHANGELOG.md

@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+
+- Fixed polyfill require not resetting recursion detection when an error occurs
+- Fixed polyfill require not returning `":preload:"`
+
 ## [0.3.1] - 2022-02-04
 
 ### Added

luapack.yue

@@ -176,10 +176,14 @@ export class Packer
                     writer\endwrap ->
                         writer\writeln 'error(("module not found %q"):format(modname), 2)'
                     writer\writeln "package.loaded[modname] = sentinel"
-                    writer\writeln 'local result = package.preload[modname](modname, ":preload:")'
+                    writer\writeln 'local success, result = pcall(package.preload[modname], modname, ":preload:")'
+                    writer\writeln "if not success then"
+                    writer\endwrap ->
+                        writer\writeln "package.loaded[modname] = nil" -- so it can be loaded again
+                        writer\writeln "error(result)" -- rethrow error
                     writer\writeln "if result == nil then result = true end"
                     writer\writeln "package.loaded[modname] = result"
-                    writer\writeln "return result"
+                    writer\writeln 'return result, ":preload:"'
 
         already_loaded = {}
         for package_name, content in pairs @loaded