fix sys path

Author: youknowone

src/lib.rs

@@ -169,14 +169,20 @@ fn run_rustpython(vm: &VirtualMachine, run_mode: RunMode) -> PyResult<()> {
 
     let scope = setup_main_module(vm)?;
 
+    // _PyPathConfig_ComputeSysPath0
     if !vm.state.config.settings.safe_path {
-        // TODO: The prepending path depends on running mode
-        // See https://docs.python.org/3/using/cmdline.html#cmdoption-P
-        vm.run_code_string(
-            vm.new_scope_with_builtins(),
-            "import sys; sys.path.insert(0, '')",
-            "<embedded>".to_owned(),
-        )?;
+        let path0: Option<String> = match &run_mode {
+            RunMode::Command(_) => Some(String::new()),
+            RunMode::Module(_) => env::current_dir()
+                .ok()
+                .and_then(|p| p.to_str().map(|s| s.to_owned())),
+            RunMode::Script(_) | RunMode::InstallPip(_) => None, // handled by run_script
+            RunMode::Repl => Some(String::new()),
+        };
+
+        if let Some(path) = path0 {
+            vm.insert_sys_path(vm.new_pyobj(path))?;
+        }
     }
 
     let site_result = vm.import("site", 0);