Add cargo runner support in order to work with cross

[glehmann]

allow to use assert_cmd with cross

cross requires to use a runner to launch the binary. It configures cargo to run the binary
with that runner, so cargo run --bin foo works just fine, but assert_cmd doesn't do that
so the execution fails.

to test it on a x86_64 computer, just run cross -v test --target aarch64-unknown-linux-gnu

Fixes #139

[epage]

I'm not sure whether it's better to introduce a dependency on escargot or copy the escargot's method to get the target triplet as I did in this PR

For this, what you did is good enough

[epage]

the test mod_example is failing but this test seems to only test escargot's features

That should have turned it into a assert_cmd::Command to verify we can integrate with escargot.

[glehmann]

the test mod_example is failing but this test seems to only test escargot's features

That should have turned it into a assert_cmd::Command to verify we can integrate with escargot.

It seems to rather be a std::process::Command, but it doesn't matter much: when we have a command (from std or assert_cmd) we have lost the information that we're dealing with a binary generated by cargo. It seems dangerous to try to guess whether the runner should be used or not :-/ And in fact the Command we get is already started inside the escargot part — we don't even have a chance to update it before launching it.

The proper fix may be to add the runner support in escargot… not sure I'll have the time to do that soon.

Would you mind if I change the test to do nothing when running in cross? Something like:

diff --git a/tests/cargo.rs b/tests/cargo.rs
index 02ba3dc..35288ab 100644
--- a/tests/cargo.rs
+++ b/tests/cargo.rs
@@ -19,15 +19,19 @@ fn cargo_binary_with_empty_env() {
 
 #[test]
 fn mod_example() {
-    let bin_under_test = escargot::CargoBuild::new()
-        .bin("bin_fixture")
-        .current_release()
-        .current_target()
-        .run()
-        .unwrap();
-    let mut cmd = bin_under_test.command();
-    let output = cmd.unwrap();
-    println!("{:?}", output);
+    if std::env::var("CROSS_SYSROOT").is_ok() {
+        // not running this test on cross because escargot doesn't support the cargo target runner yet
+    } else {
+        let bin_under_test = escargot::CargoBuild::new()
+            .bin("bin_fixture")
+            .current_release()
+            .current_target()
+            .run()
+            .unwrap();
+        let mut cmd = bin_under_test.command();
+        let output = cmd.unwrap();
+        println!("{:?}", output);
+    }
 }
 
 #[test]

That way we can still make sure that the code is compiling for the chosen target, and roll back to the normal behavior once the runner support is added in escargot

[epage]

Would you mind if I change the test to do nothing when running in cross? Something like:

Feel free

[glehmann]

The fix for cross has been merged. If it's ok for you I think we can do the same with this PR :)

[glehmann]

@epage do you see any remaining things to fix in this PR?

[glehmann]

I'm fixing the clippy warning.
I'm not sure what I can do about the Lint Commits failure however.

[glehmann]

thanks :-)