List remove, handle non exist element. Add new test

Author: janczer

tests/snippets/builtin_enumerate.py

@@ -5,6 +5,19 @@
 assert list(enumerate(['a', 'b', 'c'], -100)) == [(-100, 'a'), (-99, 'b'), (-98, 'c')]
 assert list(enumerate(['a', 'b', 'c'], 2**200)) == [(2**200, 'a'), (2**200 + 1, 'b'), (2**200 + 2, 'c')]
 
+a = list([1, 2, 3])
+assert len(a) == 3
+a.remove(1)
+assert len(a) == 2
+assert not 1 in a
+
+try:
+    a.remove(10)
+except ValueError:
+    pass
+else:
+    assert False, "Remove not exist element should raise ValueError"
+
 
 # test infinite iterator
 class Counter(object):

vm/src/obj/objlist.rs

@@ -417,9 +417,16 @@ fn list_remove(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     );
 
     let mut elements = get_mut_elements(list);
-    let i = elements.iter().position(|r| objbool::get_value(&vm._eq(needle.clone(), r.clone()).unwrap())).unwrap();
-    elements.remove(i);
-    Ok(vm.get_none())
+    let i = elements
+        .iter()
+        .position(|r| objbool::get_value(&vm._eq(needle.clone(), r.clone()).unwrap()));
+    if i.is_some() {
+        elements.remove(i.unwrap());
+        Ok(vm.get_none())
+    } else {
+        let needle_str = objstr::get_value(&vm.to_str(needle).unwrap());
+        Err(vm.new_value_error(format!("'{}' is not in list", needle_str)))
+    }
 }
 
 pub fn init(context: &PyContext) {