Add unit tests to check Derive macro output for expected error messages,
or for expected correct codegen output.
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
---
rust/qemu-api-macros/meson.build | 3 +
rust/qemu-api-macros/src/lib.rs | 3 +
rust/qemu-api-macros/src/tests.rs | 135 ++++++++++++++++++++++++++++++++++++++
rust/qemu-api-macros/src/utils.rs | 1 +
4 files changed, 142 insertions(+)
diff --git a/rust/qemu-api-macros/meson.build b/rust/qemu-api-macros/meson.build
index 8610ce1c8440c4b6e38a8462d4975bf76d72fb05..2152bcb99b30e4bdcc1c5b887b7903a37f6181c3 100644
--- a/rust/qemu-api-macros/meson.build
+++ b/rust/qemu-api-macros/meson.build
@@ -17,3 +17,6 @@ _qemu_api_macros_rs = rust.proc_macro(
qemu_api_macros = declare_dependency(
link_with: _qemu_api_macros_rs,
)
+
+rust.test('rust-qemu-api-macros-tests', _qemu_api_macros_rs,
+ suite: ['unit', 'rust'])
diff --git a/rust/qemu-api-macros/src/lib.rs b/rust/qemu-api-macros/src/lib.rs
index 4b30bea9eafc7924bf593113c3f42c5b1010c4b9..6c6e9b683f047f79cb377e6d30e23490f66bd711 100644
--- a/rust/qemu-api-macros/src/lib.rs
+++ b/rust/qemu-api-macros/src/lib.rs
@@ -15,6 +15,9 @@
mod bits;
use bits::BitsConstInternal;
+#[cfg(test)]
+mod tests;
+
fn get_fields<'a>(
input: &'a DeriveInput,
msg: &str,
diff --git a/rust/qemu-api-macros/src/tests.rs b/rust/qemu-api-macros/src/tests.rs
new file mode 100644
index 0000000000000000000000000000000000000000..dfca7d4838f141783472a4e728312aebeb9b5a8b
--- /dev/null
+++ b/rust/qemu-api-macros/src/tests.rs
@@ -0,0 +1,135 @@
+// Copyright 2025, Linaro Limited
+// Author(s): Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+use super::*;
+use quote::quote;
+
+macro_rules! derive_compile_fail {
+ ($derive_fn:ident, $input:expr, $error_msg:expr) => {{
+ let input: proc_macro2::TokenStream = $input;
+ let error_msg: &str = $error_msg;
+ let derive_fn: fn(input: syn::DeriveInput) -> Result<proc_macro2::TokenStream, MacroError> =
+ $derive_fn;
+
+ let input: syn::DeriveInput = syn::parse2(input).unwrap();
+ let result = derive_fn(input);
+ let MacroError::Message(err, _) = result.unwrap_err() else {
+ panic!()
+ };
+ assert_eq!(err, error_msg);
+ }};
+}
+
+macro_rules! derive_compile {
+ ($derive_fn:ident, $input:expr, $($expected:tt)*) => {{
+ let input: proc_macro2::TokenStream = $input;
+ let expected: proc_macro2::TokenStream = $($expected)*;
+ let derive_fn: fn(input: syn::DeriveInput) -> Result<proc_macro2::TokenStream, MacroError> =
+ $derive_fn;
+
+ let input: syn::DeriveInput = syn::parse2(input).unwrap();
+ let result = derive_fn(input).unwrap();
+ assert_eq!(result.to_string(), expected.to_string());
+ }};
+}
+
+#[test]
+fn test_derive_object() {
+ derive_compile_fail!(
+ derive_object_or_error,
+ quote! {
+ #[derive(Object)]
+ struct Foo {
+ _unused: [u8; 0],
+ }
+ },
+ "#[repr(C)] required for #[derive(Object)]"
+ );
+ derive_compile!(
+ derive_object_or_error,
+ quote! {
+ #[derive(Object)]
+ #[repr(C)]
+ struct Foo {
+ _unused: [u8; 0],
+ }
+ },
+ quote! {
+ ::qemu_api::assert_field_type!(
+ Foo,
+ _unused,
+ ::qemu_api::qom::ParentField<<Foo as ::qemu_api::qom::ObjectImpl>::ParentType>
+ );
+ ::qemu_api::module_init! {
+ MODULE_INIT_QOM => unsafe {
+ ::qemu_api::bindings::type_register_static(&<Foo as ::qemu_api::qom::ObjectImpl>::TYPE_INFO);
+ }
+ }
+ }
+ );
+}
+
+#[test]
+fn test_derive_tryinto() {
+ derive_compile_fail!(
+ derive_tryinto_or_error,
+ quote! {
+ #[derive(TryInto)]
+ struct Foo {
+ _unused: [u8; 0],
+ }
+ },
+ "#[repr(u8/u16/u32/u64) required for #[derive(TryInto)]"
+ );
+ derive_compile!(
+ derive_tryinto_or_error,
+ quote! {
+ #[derive(TryInto)]
+ #[repr(u8)]
+ enum Foo {
+ First = 0,
+ Second,
+ }
+ },
+ quote! {
+ impl Foo {
+ #[allow(dead_code)]
+ pub const fn into_bits(self) -> u8 {
+ self as u8
+ }
+
+ #[allow(dead_code)]
+ pub const fn from_bits(value: u8) -> Self {
+ match ({
+ const First: u8 = Foo::First as u8;
+ const Second: u8 = Foo::Second as u8;
+ match value {
+ First => core::result::Result::Ok(Foo::First),
+ Second => core::result::Result::Ok(Foo::Second),
+ _ => core::result::Result::Err(value),
+ }
+ }) {
+ Ok(x) => x,
+ Err(_) => panic!("invalid value for Foo"),
+ }
+ }
+ }
+
+ impl core::convert::TryFrom<u8> for Foo {
+ type Error = u8;
+
+ #[allow(ambiguous_associated_items)]
+ fn try_from(value: u8) -> Result<Self, u8> {
+ const First: u8 = Foo::First as u8;
+ const Second: u8 = Foo::Second as u8;
+ match value {
+ First => core::result::Result::Ok(Foo::First),
+ Second => core::result::Result::Ok(Foo::Second),
+ _ => core::result::Result::Err(value),
+ }
+ }
+ }
+ }
+ );
+}
diff --git a/rust/qemu-api-macros/src/utils.rs b/rust/qemu-api-macros/src/utils.rs
index 02c91aed7f6a6d33075bbaa8b4fec4536da94e60..6287d06090b60e7fc1da7fbd563d44effcc0039c 100644
--- a/rust/qemu-api-macros/src/utils.rs
+++ b/rust/qemu-api-macros/src/utils.rs
@@ -5,6 +5,7 @@
use proc_macro2::Span;
use quote::quote_spanned;
+#[derive(Debug)]
pub enum MacroError {
Message(String, Span),
ParseError(syn::Error),
--
2.47.2On Fri, Jul 04, 2025 at 01:26:58PM +0300, Manos Pitsidianakis wrote:
> Date: Fri, 04 Jul 2025 13:26:58 +0300
> From: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
> Subject: [PATCH 2/2] rust/qemu-api-macros: add unit tests
> X-Mailer: b4 0.14.2
>
> Add unit tests to check Derive macro output for expected error messages,
> or for expected correct codegen output.
>
> Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
> ---
> rust/qemu-api-macros/meson.build | 3 +
> rust/qemu-api-macros/src/lib.rs | 3 +
> rust/qemu-api-macros/src/tests.rs | 135 ++++++++++++++++++++++++++++++++++++++
> rust/qemu-api-macros/src/utils.rs | 1 +
> 4 files changed, 142 insertions(+)
>
> diff --git a/rust/qemu-api-macros/meson.build b/rust/qemu-api-macros/meson.build
> index 8610ce1c8440c4b6e38a8462d4975bf76d72fb05..2152bcb99b30e4bdcc1c5b887b7903a37f6181c3 100644
> --- a/rust/qemu-api-macros/meson.build
> +++ b/rust/qemu-api-macros/meson.build
> @@ -17,3 +17,6 @@ _qemu_api_macros_rs = rust.proc_macro(
> qemu_api_macros = declare_dependency(
> link_with: _qemu_api_macros_rs,
> )
> +
> +rust.test('rust-qemu-api-macros-tests', _qemu_api_macros_rs,
> + suite: ['unit', 'rust'])
> diff --git a/rust/qemu-api-macros/src/lib.rs b/rust/qemu-api-macros/src/lib.rs
> index 4b30bea9eafc7924bf593113c3f42c5b1010c4b9..6c6e9b683f047f79cb377e6d30e23490f66bd711 100644
> --- a/rust/qemu-api-macros/src/lib.rs
> +++ b/rust/qemu-api-macros/src/lib.rs
> @@ -15,6 +15,9 @@
> mod bits;
> use bits::BitsConstInternal;
>
> +#[cfg(test)]
> +mod tests;
> +
> fn get_fields<'a>(
> input: &'a DeriveInput,
> msg: &str,
> diff --git a/rust/qemu-api-macros/src/tests.rs b/rust/qemu-api-macros/src/tests.rs
> new file mode 100644
> index 0000000000000000000000000000000000000000..dfca7d4838f141783472a4e728312aebeb9b5a8b
> --- /dev/null
> +++ b/rust/qemu-api-macros/src/tests.rs
> @@ -0,0 +1,135 @@
> +// Copyright 2025, Linaro Limited
> +// Author(s): Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +
> +use super::*;
> +use quote::quote;
> +
> +macro_rules! derive_compile_fail {
> + ($derive_fn:ident, $input:expr, $error_msg:expr) => {{
> + let input: proc_macro2::TokenStream = $input;
> + let error_msg: &str = $error_msg;
> + let derive_fn: fn(input: syn::DeriveInput) -> Result<proc_macro2::TokenStream, MacroError> =
> + $derive_fn;
> +
> + let input: syn::DeriveInput = syn::parse2(input).unwrap();
> + let result = derive_fn(input);
> + let MacroError::Message(err, _) = result.unwrap_err() else {
> + panic!()
> + };
> + assert_eq!(err, error_msg);
> + }};
> +}
> +
> +macro_rules! derive_compile {
> + ($derive_fn:ident, $input:expr, $($expected:tt)*) => {{
> + let input: proc_macro2::TokenStream = $input;
> + let expected: proc_macro2::TokenStream = $($expected)*;
> + let derive_fn: fn(input: syn::DeriveInput) -> Result<proc_macro2::TokenStream, MacroError> =
> + $derive_fn;
> +
> + let input: syn::DeriveInput = syn::parse2(input).unwrap();
> + let result = derive_fn(input).unwrap();
> + assert_eq!(result.to_string(), expected.to_string());
> + }};
> +}
Good examples to test macros. LGTM,
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
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