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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
macro_rules! backends_map {
// one let statement per backend with mapped data
(
let map = |$backend:pat| $map:block;
$(
#[cfg($backend_cfg:meta)] let $pat:pat = map($expr:expr);
)*
) => {
$(
#[cfg($backend_cfg)]
let $pat = {
let $backend = $expr;
$map
};
)*
};
// one block statement per backend with mapped data
(
let map = |$backend:pat| $map:block;
$(
#[cfg($backend_cfg:meta)] map($expr:expr),
)*
) => {
$(
#[cfg($backend_cfg)]
{
let $backend = $expr;
$map
}
)*
};
// a struct constructor with one field per backend with mapped data
(
let map = |$backend:pat| $map:block;
$Struct:ident {
$(
#[cfg($backend_cfg:meta)] $ident:ident : map($expr:expr),
)*
}
) => {
$Struct {
$(
#[cfg($backend_cfg)]
$ident: {
let $backend = $expr;
$map
},
)*
}
};
}
#[test]
fn test_backend_macro() {
struct Foo {
#[cfg(any(
windows,
all(unix, not(any(target_os = "ios", target_os = "macos"))),
feature = "gfx-backend-vulkan",
))]
vulkan: u32,
#[cfg(any(target_os = "ios", target_os = "macos"))]
metal: u32,
#[cfg(windows)]
dx12: u32,
#[cfg(windows)]
dx11: u32,
}
// test struct construction
let test_foo: Foo = backends_map! {
let map = |init| { init - 100 };
Foo {
#[cfg(vulkan)] vulkan: map(101),
#[cfg(metal)] metal: map(102),
#[cfg(dx12)] dx12: map(103),
#[cfg(dx11)] dx11: map(104),
}
};
let mut vec = Vec::new();
// test basic statement-per-backend
backends_map! {
let map = |(id, chr)| {
vec.push((id, chr));
};
#[cfg(vulkan)]
map((test_foo.vulkan, 'a')),
#[cfg(metal)]
map((test_foo.metal, 'b')),
#[cfg(dx12)]
map((test_foo.dx12, 'c')),
#[cfg(dx11)]
map((test_foo.dx11, 'd')),
}
#[cfg(any(
windows,
all(unix, not(any(target_os = "ios", target_os = "macos"))),
feature = "gfx-backend-vulkan",
))]
assert!(vec.contains(&(1, 'a')));
#[cfg(any(target_os = "ios", target_os = "macos"))]
assert!(vec.contains(&(2, 'b')));
#[cfg(windows)]
assert!(vec.contains(&(3, 'c')));
#[cfg(windows)]
assert!(vec.contains(&(4, 'd')));
// test complex statement-per-backend
backends_map! {
let map = |(id, pred, code)| {
if pred(id) {
code();
}
};
#[cfg(vulkan)]
map((test_foo.vulkan, |v| v == 1, || println!("vulkan"))),
#[cfg(metal)]
map((test_foo.metal, |v| v == 2, || println!("metal"))),
#[cfg(dx12)]
map((test_foo.dx12, |v| v == 3, || println!("dx12"))),
#[cfg(dx11)]
map((test_foo.dx11, |v| v == 4, || println!("dx11"))),
}
// test struct construction 2
let test_foo_2: Foo = Foo {
#[cfg(vulkan)]
vulkan: 1,
#[cfg(metal)]
metal: 2,
#[cfg(dx12)]
dx12: 3,
#[cfg(dx11)]
dx11: 4,
};
#[cfg(vulkan)]
let var_vulkan = test_foo_2.vulkan;
#[cfg(metal)]
let var_metal = test_foo_2.metal;
#[cfg(dx12)]
let var_dx12 = test_foo_2.dx12;
#[cfg(dx11)]
let var_dx11 = test_foo_2.dx11;
backends_map! {
let map = |(id, chr, var)| { (chr, id, var) };
#[cfg(vulkan)]
let var_vulkan = map((test_foo_2.vulkan, 'a', var_vulkan));
#[cfg(metal)]
let var_metal = map((test_foo_2.metal, 'b', var_metal));
#[cfg(dx12)]
let var_dx12 = map((test_foo_2.dx12, 'c', var_dx12));
#[cfg(dx11)]
let var_dx11 = map((test_foo_2.dx11, 'd', var_dx11));
}
#[cfg(vulkan)]
{
println!("backend int: {:?}", var_vulkan);
}
#[cfg(metal)]
{
println!("backend int: {:?}", var_metal);
}
#[cfg(dx12)]
{
println!("backend int: {:?}", var_dx12);
}
#[cfg(dx11)]
{
println!("backend int: {:?}", var_dx11);
}
#[cfg(any(
windows,
all(unix, not(any(target_os = "ios", target_os = "macos"))),
feature = "gfx-backend-vulkan",
))]
let _ = var_vulkan;
#[cfg(any(target_os = "ios", target_os = "macos"))]
let _ = var_metal;
#[cfg(windows)]
let _ = var_dx12;
#[cfg(windows)]
let _ = var_dx11;
}
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