1 files changed, 51 insertions, 0 deletions
diff --git a/tests/ui-fulldeps/switch-stdout.rs b/tests/ui-fulldeps/switch-stdout.rs
new file mode 100644
index 00000000000..e9501a80930
--- /dev/null
+++ b/tests/ui-fulldeps/switch-stdout.rs
@@ -0,0 +1,51 @@
+// run-pass
+
+use std::env;
+use std::fs::File;
+use std::io::{Read, Write};
+use std::path::PathBuf;
+
+#[cfg(unix)]
+fn switch_stdout_to(file: File) {
+    use std::os::unix::prelude::*;
+
+    extern "C" {
+        fn dup2(old: i32, new: i32) -> i32;
+    }
+
+    unsafe {
+        assert_eq!(dup2(file.as_raw_fd(), 1), 1);
+    }
+}
+
+#[cfg(windows)]
+fn switch_stdout_to(file: File) {
+    use std::os::windows::prelude::*;
+
+    extern "system" {
+        fn SetStdHandle(nStdHandle: u32, handle: *mut u8) -> i32;
+    }
+
+    const STD_OUTPUT_HANDLE: u32 = (-11i32) as u32;
+
+    unsafe {
+        let rc = SetStdHandle(STD_OUTPUT_HANDLE, file.into_raw_handle() as *mut _);
+        assert!(rc != 0);
+    }
+}
+
+fn main() {
+    let path = PathBuf::from(env::var_os("RUST_TEST_TMPDIR").unwrap());
+    let path = path.join("switch-stdout-output");
+    let f = File::create(&path).unwrap();
+
+    println!("foo");
+    std::io::stdout().flush().unwrap();
+    switch_stdout_to(f);
+    println!("bar");
+    std::io::stdout().flush().unwrap();
+
+    let mut contents = String::new();
+    File::open(&path).unwrap().read_to_string(&mut contents).unwrap();
+    assert_eq!(contents, "bar\n");
+}