Embedded test harness for Rust no_std

Only supports ARM Cortex-M semi-hosting for now.

How to use

Add embedded_test_harness and testmacro = { git = "https://github.com/yhql/testmacro"} to Cargo.toml dev-dependencies.

Then you may write tests following this template:

```Rust

![no_std]

![cfgattr(test, nomain)]

![reexporttestharnessmain = "testmain"]

![feature(customtestframeworks)]

![testrunner(testrunner)]

use panic_semihosting as _;

[cfg(test)]

use embeddedtestharness::test_runner;

[cfg(test)]

mod tests { use testmacro::testitem as test; use embeddedtest_harness::TestType;

#[test]
fn it_works() {
    let result = 2 + 2;
    assert_eq!(result, 4);
}

}

/// _start is the entrypoint specified in the linker

[no_mangle]

pub fn start() -> ! { #[cfg(test)] testmain();

loop {}

} ```

References