run-make: port stdin-rustc to Rust-based rmake.rs

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -288,7 +288,6 @@ run-make/static-unwinding/Makefile
 run-make/staticlib-blank-lib/Makefile
 run-make/staticlib-dylib-linkage/Makefile
 run-make/std-core-cycle/Makefile
-run-make/stdin-non-utf8/Makefile
 run-make/suspicious-library/Makefile
 run-make/symbol-mangling-hashed/Makefile
 run-make/symbol-visibility/Makefile

tests/run-make/stdin-rustc/rmake.rs

@@ -0,0 +1,26 @@
+//! This test checks rustc `-` (stdin) support
+
+extern crate run_make_support;
+
+use run_make_support::{rustc, tmp_dir};
+
+const HELLO_WORLD: &str = r#"
+fn main() {
+    println!("Hello world!");
+}
+"#;
+
+const NOT_UTF8: &[u8] = &[0xff, 0xff, 0xff];
+
+fn main() {
+    let out_dir = tmp_dir();
+
+    // echo $HELLO_WORLD | rustc -
+    rustc().arg("-").stdin(HELLO_WORLD).run();
+    assert!(out_dir.join("rust_out").try_exists().unwrap());
+
+    // echo $NOT_UTF8 | rustc -
+    let output = rustc().arg("-").stdin(NOT_UTF8).run_fail();
+    let stderr = String::from_utf8(output.stderr).unwrap();
+    assert!(stderr.contains("error: couldn't read from stdin, as it did not contain valid UTF-8"));
+}