round() for int

Author: lausek

tests/snippets/numbers.py

@@ -15,6 +15,16 @@ class A(int):
 assert int(2).__floor__() == 2
 assert int(2).__round__() == 2
 assert int(2).__round__(3) == 2
+assert int(-2).__index__() == -2
+assert int(-2).__trunc__() == -2
+assert int(-2).__ceil__() == -2
+assert int(-2).__floor__() == -2
+assert int(-2).__round__() == -2
+assert int(-2).__round__(3) == -2
+
+assert round(10) == 10
+assert round(10, 2) == 10
+assert round(10, -1) == 10
 
 assert int(2).__bool__() == True
 assert int(0.5).__bool__() == False

vm/src/builtins.rs

@@ -664,7 +664,24 @@ fn builtin_repr(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     vm.to_repr(obj)
 }
 // builtin_reversed
-// builtin_round
+
+fn builtin_round(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
+    arg_check!(
+        vm,
+        args,
+        required = [(number, Some(vm.ctx.object()))],
+        optional = [(ndigits, None)]
+    );
+    if let Some(ndigits) = ndigits {
+        let ndigits = vm.call_method(ndigits, "__int__", vec![])?;
+        let rounded = vm.call_method(number, "__round__", vec![ndigits])?;
+        Ok(rounded)
+    } else {
+        // without a parameter, the result type is coerced to int
+        let rounded = &vm.call_method(number, "__round__", vec![])?;
+        Ok(vm.ctx.new_int(objint::get_value(rounded)))
+    }
+}
 
 fn builtin_setattr(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(
@@ -777,6 +794,7 @@ pub fn make_module(ctx: &PyContext) -> PyObjectRef {
     ctx.set_attr(&py_mod, "property", ctx.property_type());
     ctx.set_attr(&py_mod, "range", ctx.range_type());
     ctx.set_attr(&py_mod, "repr", ctx.new_rustfunc(builtin_repr));
+    ctx.set_attr(&py_mod, "round", ctx.new_rustfunc(builtin_round));
     ctx.set_attr(&py_mod, "set", ctx.set_type());
     ctx.set_attr(&py_mod, "setattr", ctx.new_rustfunc(builtin_setattr));
     ctx.set_attr(&py_mod, "staticmethod", ctx.staticmethod_type());

vm/src/obj/objint.rs

@@ -532,6 +532,7 @@ pub fn init(context: &PyContext) {
     context.set_attr(&int_type, "__floor__", context.new_rustfunc(int_pass_value));
     context.set_attr(&int_type, "__index__", context.new_rustfunc(int_pass_value));
     context.set_attr(&int_type, "__trunc__", context.new_rustfunc(int_pass_value));
+    context.set_attr(&int_type, "__int__", context.new_rustfunc(int_pass_value));
     context.set_attr(
         &int_type,
         "__floordiv__",