issue-1224 Change to map_err instead of match

Author: jmg7173

vm/src/obj/objstr.rs

@@ -1230,25 +1230,20 @@ fn do_cformat_specifier(
             }
             Ok(format_spec.format_number(objint::get_value(&obj)))
         }
-        CFormatType::Float(_) => {
-            let result = if objtype::isinstance(&obj, &vm.ctx.float_type()) {
-                format_spec.format_float(objfloat::get_value(&obj))
-            } else if objtype::isinstance(&obj, &vm.ctx.int_type()) {
-                format_spec.format_float(objint::get_value(&obj).to_f64().unwrap())
-            } else {
-                let required_type_string = "an floating point or integer";
-                return Err(vm.new_type_error(format!(
-                    "%{} format: {} is required, not {}",
-                    format_spec.format_char,
-                    required_type_string,
-                    obj.class()
-                )));
-            };
-            match result {
-                Ok(transformed) => Ok(transformed),
-                Err(error) => Err(vm.new_not_implemented_error(error)),
-            }
+        CFormatType::Float(_) => if objtype::isinstance(&obj, &vm.ctx.float_type()) {
+            format_spec.format_float(objfloat::get_value(&obj))
+        } else if objtype::isinstance(&obj, &vm.ctx.int_type()) {
+            format_spec.format_float(objint::get_value(&obj).to_f64().unwrap())
+        } else {
+            let required_type_string = "an floating point or integer";
+            return Err(vm.new_type_error(format!(
+                "%{} format: {} is required, not {}",
+                format_spec.format_char,
+                required_type_string,
+                obj.class()
+            )));
         }
+        .map_err(|e| vm.new_not_implemented_error(e)),
         CFormatType::Character => {
             let char_string = {
                 if objtype::isinstance(&obj, &vm.ctx.int_type()) {