cpp: escape keywords in parameters #1419
Description
I bumped into this when generating bindings for wasi:http with the cpp generator.
The best fix appears to be to use the existing c escape function in C++ since it already includes C++ keywords in addition to C.
Simple repro:
// Test file for C++ code generation fixes:
// 1. C++ keyword escaping (parameter named 'this')
// 2. Forward declarations for resources
package test:cpp-http-owned;
world cpp-http-owned {
// Test 1: Resource with forward reference
// IncomingBody returns FutureTrailers (forward declaration needed)
import test-interface: interface {
resource incoming-body {
// Static method with 'this' parameter (C++ keyword)
finish: static func(this: incoming-body) -> future-trailers;
}
resource future-trailers {
get: func() -> option<string>;
}
resource request {
// Method that returns another resource (forward declaration test)
consume: func() -> incoming-body;
}
}
// Test 2: Export interface with Owned types
export test-exports: interface {
resource request-data {
constructor();
}
resource response {
constructor();
}
// Function requiring ::Owned syntax
handle: func(req: request-data, resp: response);
}
// More C++ keywords as parameters
export keyword-test: func(this: string, class: u32, template: bool) -> string;
}Testing if `/opt/wasi-sdk-28.0-arm64-macos/bin/wasm32-wasip2-clang++` works...
Running 82 codegen tests:
........................................................................F.........
------ Failure: tests/codegen/cpp-http-owned.wit --------
language: cpp
variant: cpp-http-owned.wit
error: failed to codegen test for `cpp` over "tests/codegen/cpp-http-owned.wit"
Caused by:
0: failed to verify generated bindings
1: command execution failed
command: "/opt/wasi-sdk-28.0-arm64-macos/bin/wasm32-wasip2-clang++" "/Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/bindings/cpp_http_owned.cpp" "-I" "/Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/bindings" "-I" "/Users/bhayes/repos/bytecodealliance/wit-bindgen/crates/cpp/test_headers" "-Wall" "-Wextra" "-Werror" "-Wc++-compat" "-Wno-unused-parameter" "-std=c++20" "-c" "-o" "/Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/tmp.o"
status: exit status: 1
stderr:
In file included from /Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/bindings/cpp_http_owned.cpp:11:
/Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/bindings/cpp_http_owned_cpp.h:21:67: error: invalid parameter name: 'this' is a keyword
21 | static FutureTrailers Finish(cpp_http_owned::IncomingBody&& this);
| ^
/Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/bindings/cpp_http_owned_cpp.h:53:41: error: invalid parameter name: 'this' is a keyword
53 | wit::string KeywordTest(wit::string this, uint32_t class, bool template);
| ^
/Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/bindings/cpp_http_owned_cpp.h:53:56: error: declaration of anonymous class must be a definition
53 | wit::string KeywordTest(wit::string this, uint32_t class, bool template);
| ^
/Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/bindings/cpp_http_owned_cpp.h:53:63: error: cannot combine with previous 'type-name' declaration specifier
53 | wit::string KeywordTest(wit::string this, uint32_t class, bool template);
| ^
/Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/bindings/cpp_http_owned_cpp.h:53:68: error: invalid parameter name: 'template' is a keyword
53 | wit::string KeywordTest(wit::string this, uint32_t class, bool template);
| ^
/Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/bindings/cpp_http_owned.cpp:68:112: error: invalid parameter name: 'this' is a keyword
68 | test::cpp_http_owned::FutureTrailers test::cpp_http_owned::IncomingBody::Finish(cpp_http_owned::IncomingBody&& this)
| ^
/Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/bindings/cpp_http_owned.cpp:70:66: error: invalid use of 'this' outside of a non-static member function
70 | auto ret = test_interfaceX00X5BstaticX5Dincoming_bodyX2Efinish(this.into_handle());
| ^
/Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/bindings/cpp_http_owned.cpp:113:113: error: too many arguments to function call, expected 2, have 3
113 | auto result1 = exports::cpp_http_owned::KeywordTest(wit::string((char const*)(arg0), len0), (uint32_t(arg2)), (bool(arg3)));
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^~~~~~~~~~~~
/Users/bhayes/repos/bytecodealliance/wit-bindgen/target/artifacts/codegen/cpp/cpp-http-owned.wit/bindings/cpp_http_owned_cpp.h:53:17: note: 'KeywordTest' declared here
53 | wit::string KeywordTest(wit::string this, uint32_t class, bool template);
| ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~
8 errors generated.
1 tests FAILED