Auto merge of #23512 - oli-obk:result_ok_unwrap, r=alexcrichton

because then the call to `unwrap()` will not print the error object.

src/libcore/result.rs

@@ -78,7 +78,7 @@
 //! let bad_result: Result<int, int> = bad_result.or_else(|i| Ok(11));
 //!
 //! // Consume the result and return the contents with `unwrap`.
-//! let final_awesome_result = good_result.ok().unwrap();
+//! let final_awesome_result = good_result.unwrap();
 //! ```
 //!
 //! # Results must be used
@@ -460,7 +460,7 @@ impl<T, E> Result<T, E> {
     ///         line.trim_right().parse::<int>().unwrap_or(0)
     ///     });
     ///     // Add the value if there were no errors, otherwise add 0
-    ///     sum += val.ok().unwrap_or(0);
+    ///     sum += val.unwrap_or(0);
     /// }
     ///
     /// assert!(sum == 10);

src/librustc/middle/astencode.rs

@@ -43,6 +43,7 @@ use std::io::SeekFrom;
 use std::io::prelude::*;
 use std::num::FromPrimitive;
 use std::rc::Rc;
+use std::fmt::Debug;
 
 use rbml::reader;
 use rbml::writer::Encoder;
@@ -313,9 +314,11 @@ trait def_id_encoder_helpers {
     fn emit_def_id(&mut self, did: ast::DefId);
 }
 
-impl<S:serialize::Encoder> def_id_encoder_helpers for S {
+impl<S:serialize::Encoder> def_id_encoder_helpers for S
+    where <S as serialize::serialize::Encoder>::Error: Debug
+{
     fn emit_def_id(&mut self, did: ast::DefId) {
-        did.encode(self).ok().unwrap()
+        did.encode(self).unwrap()
     }
 }
 
@@ -325,15 +328,18 @@ trait def_id_decoder_helpers {
                          cdata: &cstore::crate_metadata) -> ast::DefId;
 }
 
-impl<D:serialize::Decoder> def_id_decoder_helpers for D {
+impl<D:serialize::Decoder> def_id_decoder_helpers for D
+    where <D as serialize::serialize::Decoder>::Error: Debug
+{
     fn read_def_id(&mut self, dcx: &DecodeContext) -> ast::DefId {
-        let did: ast::DefId = Decodable::decode(self).ok().unwrap();
+        let did: ast::DefId = Decodable::decode(self).unwrap();
         did.tr(dcx)
     }
 
     fn read_def_id_nodcx(&mut self,
-                         cdata: &cstore::crate_metadata) -> ast::DefId {
-        let did: ast::DefId = Decodable::decode(self).ok().unwrap();
+                         cdata: &cstore::crate_metadata)
+                         -> ast::DefId {
+        let did: ast::DefId = Decodable::decode(self).unwrap();
         decoder::translate_def_id(cdata, did)
     }
 }
@@ -1784,7 +1790,7 @@ impl<'a, 'tcx> rbml_decoder_decoder_helpers<'tcx> for reader::Decoder<'a> {
     fn read_closure_kind<'b, 'c>(&mut self, _dcx: &DecodeContext<'b, 'c, 'tcx>)
                                  -> ty::ClosureKind
     {
-        Decodable::decode(self).ok().unwrap()
+        Decodable::decode(self).unwrap()
     }
 
     fn read_closure_ty<'b, 'c>(&mut self, dcx: &DecodeContext<'b, 'c, 'tcx>)

src/librustc/middle/cfg/graphviz.rs

@@ -54,10 +54,10 @@ fn replace_newline_with_backslash_l(s: String) -> String {
 }
 
 impl<'a, 'ast> dot::Labeller<'a, Node<'a>, Edge<'a>> for LabelledCFG<'a, 'ast> {
-    fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new(&self.name[..]).ok().unwrap() }
+    fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new(&self.name[..]).unwrap() }
 
     fn node_id(&'a self, &(i,_): &Node<'a>) -> dot::Id<'a> {
-        dot::Id::new(format!("N{}", i.node_id())).ok().unwrap()
+        dot::Id::new(format!("N{}", i.node_id())).unwrap()
     }
 
     fn node_label(&'a self, &(i, n): &Node<'a>) -> dot::LabelText<'a> {

src/librustc/middle/infer/region_inference/graphviz.rs

@@ -69,13 +69,13 @@ pub fn maybe_print_constraints_for<'a, 'tcx>(region_vars: &RegionVarBindings<'a,
         return;
     }
 
-    let requested_output = env::var("RUST_REGION_GRAPH").ok();
+    let requested_output = env::var("RUST_REGION_GRAPH");
     debug!("requested_output: {:?} requested_node: {:?}",
            requested_output, requested_node);
 
     let output_path = {
         let output_template = match requested_output {
-            Some(ref s) if &**s == "help" => {
+            Ok(ref s) if &**s == "help" => {
                 static PRINTED_YET: AtomicBool = ATOMIC_BOOL_INIT;
                 if !PRINTED_YET.load(Ordering::SeqCst) {
                     print_help_message();
@@ -84,8 +84,8 @@ pub fn maybe_print_constraints_for<'a, 'tcx>(region_vars: &RegionVarBindings<'a,
                 return;
             }
 
-            Some(other_path) => other_path,
-            None => "/tmp/constraints.node%.dot".to_string(),
+            Ok(other_path) => other_path,
+            Err(_) => "/tmp/constraints.node%.dot".to_string(),
         };
 
         if output_template.len() == 0 {
@@ -171,7 +171,7 @@ impl<'a, 'tcx> ConstraintGraph<'a, 'tcx> {
 
 impl<'a, 'tcx> dot::Labeller<'a, Node, Edge> for ConstraintGraph<'a, 'tcx> {
     fn graph_id(&self) -> dot::Id {
-        dot::Id::new(&*self.graph_name).ok().unwrap()
+        dot::Id::new(&*self.graph_name).unwrap()
     }
     fn node_id(&self, n: &Node) -> dot::Id {
         let node_id = match self.node_ids.get(n) {

src/librustc_borrowck/borrowck/gather_loans/mod.rs

@@ -491,7 +491,7 @@ impl<'a, 'tcx, 'v> Visitor<'v> for StaticInitializerCtxt<'a, 'tcx> {
         if let ast::ExprAddrOf(mutbl, ref base) = ex.node {
             let param_env = ty::empty_parameter_environment(self.bccx.tcx);
             let mc = mc::MemCategorizationContext::new(&param_env);
-            let base_cmt = mc.cat_expr(&**base).ok().unwrap();
+            let base_cmt = mc.cat_expr(&**base).unwrap();
             let borrow_kind = ty::BorrowKind::from_mutbl(mutbl);
             // Check that we don't allow borrows of unsafe static items.
             if check_aliasability(self.bccx, ex.span, euv::AddrOf,

src/libstd/fs/mod.rs

@@ -1537,7 +1537,7 @@ mod tests {
     #[test]
     fn binary_file() {
         let mut bytes = [0; 1024];
-        StdRng::new().ok().unwrap().fill_bytes(&mut bytes);
+        StdRng::new().unwrap().fill_bytes(&mut bytes);
 
         let tmpdir = tmpdir();
 

src/libstd/io/cursor.rs

@@ -277,7 +277,7 @@ mod tests {
     fn read_to_end() {
         let mut reader = Cursor::new(vec!(0, 1, 2, 3, 4, 5, 6, 7));
         let mut v = Vec::new();
-        reader.read_to_end(&mut v).ok().unwrap();
+        reader.read_to_end(&mut v).unwrap();
         assert_eq!(v, [0, 1, 2, 3, 4, 5, 6, 7]);
     }
 

src/libstd/net/addr.rs

@@ -617,7 +617,7 @@ mod tests {
                  unique_local: bool, global: bool,
                  u_link_local: bool, u_site_local: bool, u_global: bool,
                  m_scope: Option<Ipv6MulticastScope>) {
-            let ip: Ipv6Addr = str_addr.parse().ok().unwrap();
+            let ip: Ipv6Addr = str_addr.parse().unwrap();
             assert_eq!(str_addr, ip.to_string());
 
             assert_eq!(ip.is_unspecified(), unspec);

src/libstd/old_io/fs.rs

@@ -1608,7 +1608,7 @@ mod test {
         use rand::{StdRng, Rng};
 
         let mut bytes = [0; 1024];
-        StdRng::new().ok().unwrap().fill_bytes(&mut bytes);
+        StdRng::new().unwrap().fill_bytes(&mut bytes);
 
         let tmpdir = tmpdir();
 

src/libstd/sync/mpsc/mod.rs

@@ -592,7 +592,7 @@ impl<T: Send> Sender<T> {
                                 // asleep (we're looking at it), so the receiver
                                 // can't go away.
                                 (*a.get()).send(t).ok().unwrap();
-                        token.signal();
+                                token.signal();
                                 (a, Ok(()))
                             }
                         }

src/libstd/sys/unix/backtrace.rs

@@ -454,7 +454,7 @@ fn output(w: &mut Write, idx: int, addr: *mut libc::c_void,
 #[allow(dead_code)]
 fn output_fileline(w: &mut Write, file: &[u8], line: libc::c_int,
                    more: bool) -> io::Result<()> {
-    let file = str::from_utf8(file).ok().unwrap_or("<unknown>");
+    let file = str::from_utf8(file).unwrap_or("<unknown>");
     // prior line: "  ##: {:2$} - func"
     try!(write!(w, "      {:3$}at {}:{}", "", file, line, HEX_WIDTH));
     if more {

src/libstd/sys/unix/fs.rs

@@ -391,7 +391,7 @@ mod tests {
         let mut reader = FileDesc::new(reader, true);
         let mut writer = FileDesc::new(writer, true);
 
-        writer.write(b"test").ok().unwrap();
+        writer.write(b"test").unwrap();
         let mut buf = [0; 4];
         match reader.read(&mut buf) {
             Ok(4) => {

src/libstd/sys/unix/helper_signal.rs

@@ -23,7 +23,7 @@ pub fn new() -> (signal, signal) {
 }
 
 pub fn signal(fd: libc::c_int) {
-    FileDesc::new(fd, false).write(&[0]).ok().unwrap();
+    FileDesc::new(fd, false).write(&[0]).unwrap();
 }
 
 pub fn close(fd: libc::c_int) {

src/libstd/sys/unix/timer.rs

@@ -204,7 +204,7 @@ fn helper(input: libc::c_int, messages: Receiver<Req>, _: ()) {
 
                 // drain the file descriptor
                 let mut buf = [0];
-                assert_eq!(fd.read(&mut buf).ok().unwrap(), 1);
+                assert_eq!(fd.read(&mut buf).unwrap(), 1);
             }
 
             -1 if os::errno() == libc::EINTR as i32 => {}

src/libstd/sys/windows/pipe.rs

@@ -757,10 +757,10 @@ impl UnixAcceptor {
 
 impl Clone for UnixAcceptor {
     fn clone(&self) -> UnixAcceptor {
-        let name = to_utf16(&self.listener.name).ok().unwrap();
+        let name = to_utf16(&self.listener.name).unwrap();
         UnixAcceptor {
             inner: self.inner.clone(),
-            event: Event::new(true, false).ok().unwrap(),
+            event: Event::new(true, false).unwrap(),
             deadline: 0,
             listener: UnixListener {
                 name: self.listener.name.clone(),

src/libstd/thread.rs

@@ -869,7 +869,7 @@ mod test {
             Err(e) => {
                 type T = &'static str;
                 assert!(e.is::<T>());
-                assert_eq!(*e.downcast::<T>().ok().unwrap(), "static string");
+                assert_eq!(*e.downcast::<T>().unwrap(), "static string");
             }
             Ok(()) => panic!()
         }
@@ -883,7 +883,7 @@ mod test {
             Err(e) => {
                 type T = String;
                 assert!(e.is::<T>());
-                assert_eq!(*e.downcast::<T>().ok().unwrap(), "owned string".to_string());
+                assert_eq!(*e.downcast::<T>().unwrap(), "owned string".to_string());
             }
             Ok(()) => panic!()
         }
@@ -897,9 +897,9 @@ mod test {
             Err(e) => {
                 type T = Box<Any + Send>;
                 assert!(e.is::<T>());
-                let any = e.downcast::<T>().ok().unwrap();
+                let any = e.downcast::<T>().unwrap();
                 assert!(any.is::<u16>());
-                assert_eq!(*any.downcast::<u16>().ok().unwrap(), 413);
+                assert_eq!(*any.downcast::<u16>().unwrap(), 413);
             }
             Ok(()) => panic!()
         }

src/libsyntax/ext/deriving/encodable.rs

@@ -64,7 +64,7 @@
 //!     fn encode(&self, s: &mut S) -> Result<(), E> {
 //!         s.emit_struct("Spanned", 2, |this| {
 //!             this.emit_struct_field("node", 0, |this| self.node.encode(this))
-//!                 .ok().unwrap();
+//!                 .unwrap();
 //!             this.emit_struct_field("span", 1, |this| self.span.encode(this))
 //!         })
 //!     }
@@ -79,9 +79,9 @@
 //!         d.read_struct("Spanned", 2, |this| {
 //!             Ok(Spanned {
 //!                 node: this.read_struct_field("node", 0, |this| Decodable::decode(this))
-//!                     .ok().unwrap(),
+//!                     .unwrap(),
 //!                 span: this.read_struct_field("span", 1, |this| Decodable::decode(this))
-//!                     .ok().unwrap(),
+//!                     .unwrap(),
 //!             })
 //!         })
 //!     }

src/libsyntax/parse/lexer/mod.rs

@@ -623,7 +623,7 @@ impl<'a> StringReader<'a> {
         // find the integer representing the name
         self.scan_digits(base);
         let encoded_name : u32 = self.with_str_from(start_bpos, |s| {
-            num::from_str_radix(s, 10).ok().unwrap_or_else(|| {
+            num::from_str_radix(s, 10).unwrap_or_else(|_| {
                 panic!("expected digits representing a name, got {:?}, {}, range [{:?},{:?}]",
                       s, whence, start_bpos, self.last_pos);
             })
@@ -641,7 +641,7 @@ impl<'a> StringReader<'a> {
         let start_bpos = self.last_pos;
         self.scan_digits(base);
         let encoded_ctxt : ast::SyntaxContext = self.with_str_from(start_bpos, |s| {
-            num::from_str_radix(s, 10).ok().unwrap_or_else(|| {
+            num::from_str_radix(s, 10).unwrap_or_else(|_| {
                 panic!("expected digits representing a ctxt, got {:?}, {}", s, whence);
             })
         });

src/libterm/terminfo/mod.rs

@@ -181,21 +181,24 @@ impl<T: Write+Send+'static> TerminfoTerminal<T> {
             }
         };
 
-        let entry = open(&term[..]);
-        if entry.is_err() {
-            if env::var("MSYSCON").ok().map_or(false, |s| {
-                    "mintty.exe" == s
-                }) {
-                // msys terminal
-                return Some(box TerminfoTerminal {out: out,
-                                                  ti: msys_terminfo(),
-                                                  num_colors: 8} as Box<Terminal<T>+Send>);
-            }
-            debug!("error finding terminfo entry: {:?}", entry.err().unwrap());
-            return None;
-        }
+        let mut file = match open(&term[..]) {
+            Ok(f) => f,
+            Err(err) => return match env::var("MSYSCON") {
+                Ok(ref val) if &val[..] == "mintty.exe" => {
+                    // msys terminal
+                    Some(box TerminfoTerminal{
+                        out: out,
+                        ti: msys_terminfo(),
+                        num_colors: 8,
+                    } as Box<Terminal<T>+Send>)
+                },
+                _ => {
+                    debug!("error finding terminfo entry: {:?}", err);
+                    None
+                },
+            },
+        };
 
-        let mut file = entry.unwrap();
         let ti = parse(&mut file, false);
         if ti.is_err() {
             debug!("error parsing terminfo entry: {:?}", ti.err().unwrap());

src/test/run-pass/spawn2.rs

@@ -12,7 +12,7 @@ use std::thread;
 
 pub fn main() {
     let t = thread::spawn(move|| child((10, 20, 30, 40, 50, 60, 70, 80, 90)) );
-    t.join().ok().unwrap();
+    t.join().ok().unwrap(); // forget Err value, since it doesn't implement Debug
 }
 
 fn child(args: (int, int, int, int, int, int, int, int, int)) {

src/test/run-pass/unit-like-struct-drop-run.rs

@@ -26,6 +26,6 @@ pub fn main() {
         let _b = Foo;
     }).join();
 
-    let s = x.err().unwrap().downcast::<&'static str>().ok().unwrap();
+    let s = x.err().unwrap().downcast::<&'static str>().unwrap();
     assert_eq!(&**s, "This panic should happen.");
 }