Add a test for unit test of proc-macro crate

test-cargo-miri/run-test.py

@@ -102,7 +102,7 @@ def test_cargo_miri_test():
     )
     test("`cargo miri test` (subcrate, no isolation)",
         cargo_miri("test") + ["-p", "subcrate"],
-        "test.subcrate.stdout.ref", "test.stderr-empty.ref",
+        "test.subcrate.stdout.ref", "test.stderr-proc-macro.ref",
         env={'MIRIFLAGS': "-Zmiri-disable-isolation"},
     )
 

test-cargo-miri/subcrate/Cargo.toml

@@ -4,6 +4,10 @@ version = "0.1.0"
 authors = ["Miri Team"]
 edition = "2018"
 
+[lib]
+proc-macro = true
+doctest = false
+
 [[bin]]
 name = "subcrate"
 path = "main.rs"

test-cargo-miri/subcrate/src/lib.rs

@@ -0,0 +1,2 @@
+#[cfg(test)]
+compile_error!("Miri should not touch me");

test-cargo-miri/test.stderr-proc-macro.ref

@@ -0,0 +1 @@
+Running unit tests of `proc-macro` crates is not currently supported by Miri.