From 276f2e7e6cf0149d56ca72c780e963938feb7206 Mon Sep 17 00:00:00 2001 From: Matt Corallo Date: Fri, 17 Jun 2022 21:00:39 +0000 Subject: [PATCH] Check whether the fields of an enum are clonable before implementing clone --- c-bindings-gen/src/main.rs | 51 ++++++++++++++++++++++++++++++++------ 1 file changed, 43 insertions(+), 8 deletions(-) diff --git a/c-bindings-gen/src/main.rs b/c-bindings-gen/src/main.rs index 76938ba..b9dba8c 100644 --- a/c-bindings-gen/src/main.rs +++ b/c-bindings-gen/src/main.rs @@ -1594,8 +1594,37 @@ fn writeln_enum<'a, 'b, W: std::io::Write>(w: &mut W, e: &'a syn::ItemEnum, type let mut needs_free = false; let mut constr = Vec::new(); + let mut is_clonable = true; - writeln!(w, "#[must_use]\n#[derive(Clone)]\n#[repr(C)]\npub enum {} {{", e.ident).unwrap(); + for var in e.variants.iter() { + if let syn::Fields::Named(fields) = &var.fields { + needs_free = true; + for field in fields.named.iter() { + if export_status(&field.attrs) == ExportStatus::TestOnly { continue; } + + let mut ty_checks = Vec::new(); + types.write_c_type(&mut ty_checks, &field.ty, Some(&gen_types), false); + if !types.is_clonable(&String::from_utf8(ty_checks).unwrap()) { + is_clonable = false; + } + } + } else if let syn::Fields::Unnamed(fields) = &var.fields { + for field in fields.unnamed.iter() { + let mut ty_checks = Vec::new(); + types.write_c_type(&mut ty_checks, &field.ty, Some(&gen_types), false); + let ty = String::from_utf8(ty_checks).unwrap(); + if ty != "" && !types.is_clonable(&ty) { + is_clonable = false; + } + } + } + } + + if is_clonable { + writeln!(w, "#[derive(Clone)]").unwrap(); + types.crate_types.set_clonable(format!("{}::{}", types.module_path, e.ident)); + } + writeln!(w, "#[must_use]\n#[repr(C)]\npub enum {} {{", e.ident).unwrap(); for var in e.variants.iter() { assert_eq!(export_status(&var.attrs), ExportStatus::Export); // We can't partially-export a mirrored enum writeln_docs(w, &var.attrs, "\t"); @@ -1803,9 +1832,13 @@ fn writeln_enum<'a, 'b, W: std::io::Write>(w: &mut W, e: &'a syn::ItemEnum, type } } - write_conv!(format!("to_native(&self) -> native{}", e.ident), false, true); + if is_clonable { + write_conv!(format!("to_native(&self) -> native{}", e.ident), false, true); + } write_conv!(format!("into_native(self) -> native{}", e.ident), false, false); - write_conv!(format!("from_native(native: &native{}) -> Self", e.ident), true, true); + if is_clonable { + write_conv!(format!("from_native(native: &native{}) -> Self", e.ident), true, true); + } write_conv!(format!("native_into(native: native{}) -> Self", e.ident), true, false); writeln!(w, "}}").unwrap(); @@ -1813,11 +1846,13 @@ fn writeln_enum<'a, 'b, W: std::io::Write>(w: &mut W, e: &'a syn::ItemEnum, type writeln!(w, "/// Frees any resources used by the {}", e.ident).unwrap(); writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", e.ident, e.ident).unwrap(); } - writeln!(w, "/// Creates a copy of the {}", e.ident).unwrap(); - writeln!(w, "#[no_mangle]").unwrap(); - writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", e.ident, e.ident, e.ident).unwrap(); - writeln!(w, "\torig.clone()").unwrap(); - writeln!(w, "}}").unwrap(); + if is_clonable { + writeln!(w, "/// Creates a copy of the {}", e.ident).unwrap(); + writeln!(w, "#[no_mangle]").unwrap(); + writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", e.ident, e.ident, e.ident).unwrap(); + writeln!(w, "\torig.clone()").unwrap(); + writeln!(w, "}}").unwrap(); + } w.write_all(&constr).unwrap(); write_cpp_wrapper(cpp_headers, &format!("{}", e.ident), needs_free, None); } -- 2.30.2