Merge pull request #355 from NLincoln/compliant-complex-repr

repr() of complex numbers is compliant with cpython

tests/snippets/basic_types.py

@@ -44,6 +44,9 @@ assert int() == 0
 a = complex(2, 4)
 assert type(a) is complex
 assert type(a + a) is complex
+assert repr(a) == '(2+4j)'
+a = 10j
+assert repr(a) == '10j'
 
 a = 1
 assert a.conjugate() == a

vm/src/obj/objcomplex.rs

@@ -85,5 +85,10 @@ fn complex_conjugate(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
 fn complex_repr(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(vm, args, required = [(obj, Some(vm.ctx.complex_type()))]);
     let v = get_value(obj);
-    Ok(vm.new_str(v.to_string()))
+    let repr = if v.re == 0. {
+        format!("{}j", v.im)
+    } else {
+        format!("({}+{}j)", v.re, v.im)
+    };
+    Ok(vm.new_str(repr))
 }