Skip to content

Make data-carrying enums emit #[derive(Debug)] on the Rust side #209

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
amsam0 wants to merge 4 commits into
base: master
Choose a base branch
from
Open

Make data-carrying enums emit #[derive(Debug)] on the Rust side #209

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
3b37099
fix: derive(Debug) on the Rust side even if one of the variants has data
amsam0 Apr 7, 2023
c8e853c
fix: don't generate Debug functions in C header and Swift if any vari…
amsam0 Apr 7, 2023
9ee0b05
docs: move comment
amsam0 Apr 7, 2023
cc1e577
Merge branch 'chinedufn:master' into derive-debug-fixes
amsam0 Aug 12, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 3 additions & 1 deletion crates/swift-bridge-ir/src/codegen/generate_c_header.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -164,7 +164,9 @@ typedef struct {option_ffi_name} {{ bool is_some; {ffi_name} val; }} {option_ffi
variants += &variant;
}

let derive_debug_impl = if ty_enum.derive.debug {
let derive_debug_impl = if ty_enum.derive.debug
&& !ty_enum.has_one_or_more_variants_with_data()
{
format!("void* {ffi_name}$Debug({ffi_name} this);")
} else {
"".to_string()
Expand Down
33 changes: 19 additions & 14 deletions crates/swift-bridge-ir/src/codegen/generate_rust_tokens/shared_enum.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -140,22 +140,27 @@ impl SwiftBridgeModule {
// User derives
let mut derive_impl_ffi_bridges = vec![];

// We currently only allow derive(Debug) on non data carrying enums in order
// to prevent a potential memory safety issue.
// https://github.com/chinedufn/swift-bridge/pull/194#discussion_r1134386788
if shared_enum.derive.debug && !shared_enum.has_one_or_more_variants_with_data() {
if shared_enum.derive.debug {
// We don't want to confuse the developer if one of our variants has data and Debug isn't derived,
// so we still want to derive(Debug) on the Rust side.
// TODO: push a warning if one of our variants has data?
derives.push(quote! {::std::fmt::Debug});

// __swift_bridge__$SomeEnum$Debug
let export_name = format!("{}$Debug", shared_enum.ffi_name_string());
// __swift_bridge__SomeEnum_Debug
let fn_name = format_ident!("{}_Debug", enum_ffi_name);
derive_impl_ffi_bridges.push(quote! {
#[export_name = #export_name]
pub extern "C" fn #fn_name(this: #enum_ffi_name) -> *mut swift_bridge::string::RustString {
swift_bridge::string::RustString(format!("{:?}", this.into_rust_repr())).box_into_raw()
}
});
// We currently only allow derive(Debug) on non data carrying enums in order
// to prevent a potential memory safety issue.
// https://github.com/chinedufn/swift-bridge/pull/194#discussion_r1134386788
if !shared_enum.has_one_or_more_variants_with_data() {
// __swift_bridge__$SomeEnum$Debug
let export_name = format!("{}$Debug", shared_enum.ffi_name_string());
// __swift_bridge__SomeEnum_Debug
let fn_name = format_ident!("{}_Debug", enum_ffi_name);
derive_impl_ffi_bridges.push(quote! {
#[export_name = #export_name]
pub extern "C" fn #fn_name(this: #enum_ffi_name) -> *mut swift_bridge::string::RustString {
swift_bridge::string::RustString(format!("{:?}", this.into_rust_repr())).box_into_raw()
}
});
}
}

let vec_support = if shared_enum.has_one_or_more_variants_with_data() {
Expand Down
15 changes: 8 additions & 7 deletions crates/swift-bridge-ir/src/codegen/generate_swift/shared_enum.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -145,18 +145,19 @@ extension {enum_name}: Vectorizable {{
)
};

let derive_debug_impl = if shared_enum.derive.debug {
format!(
r#"
let derive_debug_impl =
if shared_enum.derive.debug && !shared_enum.has_one_or_more_variants_with_data() {
format!(
r#"
extension {enum_name}: CustomDebugStringConvertible {{
public var debugDescription: String {{
RustString(ptr: __swift_bridge__${enum_name}$Debug(self.intoFfiRepr())).toString()
}}
}}"#
)
} else {
"".to_string()
};
)
} else {
"".to_string()
};

let swift_enum = format!(
r#"public enum {enum_name} {{{variants}}}
Expand Down