Change the sigs of set_print/set_panic to allow restoring the default objects

Author: brson

src/librustc_driver/lib.rs

@@ -1075,7 +1075,7 @@ pub fn monitor<F: FnOnce() + Send + 'static>(f: F) {
     }
 
     let thread = cfg.spawn(move || {
-         io::set_panic(box err);
+         io::set_panic(Some(box err));
          f()
      });
 
@@ -1121,7 +1121,7 @@ fn exit_on_err() -> ! {
     // Panic so the process returns a failure code, but don't pollute the
     // output with some unnecessary panic messages, we've already
     // printed everything that we needed to.
-    io::set_panic(box io::sink());
+    io::set_panic(Some(box io::sink()));
     panic!();
 }
 

src/librustdoc/test.rs

@@ -228,7 +228,7 @@ fn runtest(test: &str, cratename: &str, cfgs: Vec<String>, libs: SearchPaths,
     let codemap = Rc::new(CodeMap::new());
     let emitter = errors::emitter::EmitterWriter::new(box Sink(data.clone()),
                                                       Some(codemap.clone()));
-    let old = io::set_panic(box Sink(data.clone()));
+    let old = io::set_panic(Some(box Sink(data.clone())));
     let _bomb = Bomb(data.clone(), old.unwrap_or(box io::stdout()));
 
     // Compile the code

src/libstd/io/stdio.rs

@@ -593,11 +593,11 @@ impl<'a> Write for StderrLock<'a> {
                      with a more general mechanism",
            issue = "0")]
 #[doc(hidden)]
-pub fn set_panic(sink: Box<Write + Send>) -> Option<Box<Write + Send>> {
+pub fn set_panic(sink: Option<Box<Write + Send>>) -> Option<Box<Write + Send>> {
     use panicking::LOCAL_STDERR;
     use mem;
     LOCAL_STDERR.with(move |slot| {
-        mem::replace(&mut *slot.borrow_mut(), Some(sink))
+        mem::replace(&mut *slot.borrow_mut(), sink)
     }).and_then(|mut s| {
         let _ = s.flush();
         Some(s)
@@ -617,10 +617,10 @@ pub fn set_panic(sink: Box<Write + Send>) -> Option<Box<Write + Send>> {
                      with a more general mechanism",
            issue = "0")]
 #[doc(hidden)]
-pub fn set_print(sink: Box<Write + Send>) -> Option<Box<Write + Send>> {
+pub fn set_print(sink: Option<Box<Write + Send>>) -> Option<Box<Write + Send>> {
     use mem;
     LOCAL_STDOUT.with(move |slot| {
-        mem::replace(&mut *slot.borrow_mut(), Some(sink))
+        mem::replace(&mut *slot.borrow_mut(), sink)
     }).and_then(|mut s| {
         let _ = s.flush();
         Some(s)

src/libtest/lib.rs

@@ -1200,8 +1200,8 @@ pub fn run_test(opts: &TestOpts,
 
                 let result_guard = cfg.spawn(move || {
                     if !nocapture {
-                        io::set_print(box Sink(data2.clone()));
-                        io::set_panic(box Sink(data2));
+                        io::set_print(Some(box Sink(data2.clone())));
+                        io::set_panic(Some(box Sink(data2)));
                     }
                     testfn()
                 })
@@ -1213,8 +1213,8 @@ pub fn run_test(opts: &TestOpts,
         } else {
             let oldio = if !nocapture {
                 Some((
-                    io::set_print(box Sink(data2.clone())),
-                    io::set_panic(box Sink(data2))
+                    io::set_print(Some(box Sink(data2.clone()))),
+                    io::set_panic(Some(box Sink(data2)))
                 ))
             } else {
                 None
@@ -1227,12 +1227,8 @@ pub fn run_test(opts: &TestOpts,
             }));
 
             if let Some((printio, panicio)) = oldio {
-                if let Some(printio) = printio {
-                    io::set_print(printio);
-                }
-                if let Some(panicio) = panicio {
-                    io::set_panic(panicio);
-                }
+                io::set_print(printio);
+                io::set_panic(panicio);
             };
 
             let test_result = calc_result(&desc, result);

src/test/run-pass/task-stderr.rs

@@ -30,7 +30,7 @@ fn main() {
     let data = Arc::new(Mutex::new(Vec::new()));
     let sink = Sink(data.clone());
     let res = thread::Builder::new().spawn(move|| -> () {
-        io::set_panic(Box::new(sink));
+        io::set_panic(Some(Box::new(sink)));
         panic!("Hello, world!")
     }).unwrap().join();
     assert!(res.is_err());