Implement support for sys.path when loading modules.

sys.path is not initialized by rt_init(), that's left for platform-specific
startup code. (For example, bare metal port may have some hardcoded defaults,
and let user change sys.path directly; while port for OS with environment
feature can take path from environment). If it's not explicitly initialized,
modules will be imported only from a current directory.

1 files changed, 7 insertions, 1 deletions

diff --git a/py/runtime.c b/py/runtime.c
index c84a28e4c..6d3cbf85b 100644
--- a/py/runtime.c
+++ b/py/runtime.c
@@ -168,8 +168,14 @@ void rt_init(void) {
 
 #if MICROPY_CPYTHON_COMPAT
     // Precreate sys module, so "import sys" didn't throw exceptions.
-    mp_obj_new_module(MP_QSTR_sys);
+    mp_obj_t m_sys = mp_obj_new_module(MP_QSTR_sys);
+    // Avoid warning of unused var
+    (void)m_sys;
 #endif
+    // init sys.path
+    // for efficiency, left to platform-specific startup code
+    //sys_path = mp_obj_new_list(0, NULL);
+    //rt_store_attr(m_sys, MP_QSTR_path, sys_path);
 
     mp_module_micropython_init();