From 6d11fdcd18546cdd9bafd1f81b61ecc328654dd6 Mon Sep 17 00:00:00 2001
From: J Henry Waugh <jhwgh1968@protonmail.com>
Date: Tue, 11 Aug 2020 19:05:52 -0500
Subject: [PATCH] codegen: replace downcast_clone with more efficient mem::take

---
 codegen/src/function.rs | 19 +++++++++----------
 codegen/src/module.rs   |  8 ++++----
 2 files changed, 13 insertions(+), 14 deletions(-)

diff --git a/codegen/src/function.rs b/codegen/src/function.rs
index 7b28eeeb..ae50e45a 100644
--- a/codegen/src/function.rs
+++ b/codegen/src/function.rs
@@ -356,16 +356,15 @@ impl ExportedFn {
                             &syn::Type::Path(ref p) if p.path == str_type_path => {
                                 is_str_ref = true;
                                 quote_spanned!(arg_type.span()=>
-                                                   args[#i]
-                                                   .downcast_clone::<ImmutableString>()
-                                                   .unwrap())
+                                                   std::mem::take(args[#i])
+                                                   .clone().cast::<ImmutableString>())
                             }
                             _ => panic!("internal error: why wasn't this found earlier!?"),
                         },
                         _ => {
                             is_str_ref = false;
                             quote_spanned!(arg_type.span()=>
-                                            args[#i].downcast_clone::<#arg_type>().unwrap())
+                                           std::mem::take(args[#i]).clone().cast::<#arg_type>())
                         }
                     };
 
@@ -768,7 +767,7 @@ mod generate_tests {
                                     format!("wrong arg count: {} != {}",
                                             args.len(), 1usize), Position::none())));
                         }
-                        let arg0 = args[0usize].downcast_clone::<usize>().unwrap();
+                        let arg0 = std::mem::take(args[0usize]).clone().cast::<usize>();
                         Ok(Dynamic::from(do_something(arg0)))
                     }
 
@@ -808,7 +807,7 @@ mod generate_tests {
                                 format!("wrong arg count: {} != {}",
                                         args.len(), 1usize), Position::none())));
                     }
-                    let arg0 = args[0usize].downcast_clone::<usize>().unwrap();
+                    let arg0 = std::mem::take(args[0usize]).clone().cast::<usize>();
                     Ok(Dynamic::from(do_something(arg0)))
                 }
 
@@ -845,8 +844,8 @@ mod generate_tests {
                                     format!("wrong arg count: {} != {}",
                                             args.len(), 2usize), Position::none())));
                         }
-                        let arg0 = args[0usize].downcast_clone::<usize>().unwrap();
-                        let arg1 = args[1usize].downcast_clone::<usize>().unwrap();
+                        let arg0 = std::mem::take(args[0usize]).clone().cast::<usize>();
+                        let arg1 = std::mem::take(args[1usize]).clone().cast::<usize>();
                         Ok(Dynamic::from(add_together(arg0, arg1)))
                     }
 
@@ -891,7 +890,7 @@ mod generate_tests {
                                     format!("wrong arg count: {} != {}",
                                             args.len(), 2usize), Position::none())));
                         }
-                        let arg1 = args[1usize].downcast_clone::<usize>().unwrap();
+                        let arg1 = std::mem::take(args[1usize]).clone().cast::<usize>();
                         let arg0: &mut _ = &mut args[0usize].write_lock::<usize>().unwrap();
                         Ok(Dynamic::from(increment(arg0, arg1)))
                     }
@@ -938,7 +937,7 @@ mod generate_tests {
                                     format!("wrong arg count: {} != {}",
                                             args.len(), 1usize), Position::none())));
                         }
-                        let arg0 = args[0usize].downcast_clone::<ImmutableString>().unwrap();
+                        let arg0 = std::mem::take(args[0usize]).clone().cast::<ImmutableString>();
                         Ok(Dynamic::from(special_print(&arg0)))
                     }
 
diff --git a/codegen/src/module.rs b/codegen/src/module.rs
index 9db6a3cd..256ca062 100644
--- a/codegen/src/module.rs
+++ b/codegen/src/module.rs
@@ -371,7 +371,7 @@ mod generate_tests {
                                     format!("wrong arg count: {} != {}",
                                             args.len(), 1usize), Position::none())));
                         }
-                        let arg0 = args[0usize].downcast_clone::<INT>().unwrap();
+                        let arg0 = std::mem::take(args[0usize]).clone().cast::<INT>();
                         Ok(Dynamic::from(add_one_to(arg0)))
                     }
 
@@ -433,8 +433,8 @@ mod generate_tests {
                                     format!("wrong arg count: {} != {}",
                                             args.len(), 2usize), Position::none())));
                         }
-                        let arg0 = args[0usize].downcast_clone::<INT>().unwrap();
-                        let arg1 = args[1usize].downcast_clone::<INT>().unwrap();
+                        let arg0 = std::mem::take(args[0usize]).clone().cast::<INT>();
+                        let arg1 = std::mem::take(args[1usize]).clone().cast::<INT>();
                         Ok(Dynamic::from(add_together(arg0, arg1)))
                     }
 
@@ -605,7 +605,7 @@ mod generate_tests {
                                     format!("wrong arg count: {} != {}",
                                             args.len(), 1usize), Position::none())));
                         }
-                        let arg0 = args[0usize].downcast_clone::<ImmutableString>().unwrap();
+                        let arg0 = std::mem::take(args[0usize]).clone().cast::<ImmutableString>();
                         Ok(Dynamic::from(print_out_to(&arg0)))
                     }