Issue #7444 - Borrowck permits moved values to be captured

src/libextra/dlist.rs

@@ -173,11 +173,11 @@ impl<T> Deque<T> for DList<T> {
                 let tail_own = match tail.prev.resolve() {
                     None => {
                         self.list_tail = Rawlink::none();
-                        self.list_head.swap_unwrap()
+                        self.list_head.take_unwrap()
                     },
                     Some(tail_prev) => {
                         self.list_tail = tail.prev;
-                        tail_prev.next.swap_unwrap()
+                        tail_prev.next.take_unwrap()
                     }
                 };
                 Some(tail_own.value)
@@ -465,7 +465,7 @@ impl<'self, A> ListInsertion<A> for MutDListIterator<'self, A> {
                     Some(prev) => prev,
                 };
                 let mut ins_node = ~Node{value: elt, next: None, prev: Rawlink::none()};
-                let node_own = prev_node.next.swap_unwrap();
+                let node_own = prev_node.next.take_unwrap();
                 ins_node.next = link_with_prev(node_own, Rawlink::some(ins_node));
                 prev_node.next = link_with_prev(ins_node, Rawlink::some(prev_node));
                 self.list.length += 1;

src/libextra/net/ip.rs

@@ -116,7 +116,7 @@ pub fn get_addr(node: &str, iotask: &iotask)
     let (output_po, output_ch) = stream();
     let mut output_ch = Some(SharedChan::new(output_ch));
     do str::as_buf(node) |node_ptr, len| {
-        let output_ch = output_ch.swap_unwrap();
+        let output_ch = output_ch.take_unwrap();
         debug!("slice len %?", len);
         let handle = create_uv_getaddrinfo_t();
         let handle_ptr: *uv_getaddrinfo_t = &handle;

src/libextra/smallintmap.rs

@@ -161,8 +161,8 @@ impl<V> SmallIntMap<V> {
     /// Visit all key-value pairs in reverse order
     pub fn each_reverse<'a>(&'a self, it: &fn(uint, &'a V) -> bool) -> bool {
         for uint::range_rev(self.v.len(), 0) |i| {
-            match self.v[i - 1] {
-              Some(ref elt) => if !it(i - 1, elt) { return false; },
+            match self.v[i] {
+              Some(ref elt) => if !it(i, elt) { return false; },
               None => ()
             }
         }

src/libextra/sync.rs

@@ -260,7 +260,7 @@ impl<'self> Condvar<'self> {
                             signal_waitqueue(&state.waiters);
                         }
                         // Enqueue ourself to be woken up by a signaller.
-                        let SignalEnd = SignalEnd.swap_unwrap();
+                        let SignalEnd = SignalEnd.take_unwrap();
                         state.blocked[condvar_id].tail.send(SignalEnd);
                     } else {
                         out_of_bounds = Some(state.blocked.len());
@@ -281,7 +281,7 @@ impl<'self> Condvar<'self> {
             // Unconditionally "block". (Might not actually block if a
             // signaller already sent -- I mean 'unconditionally' in contrast
             // with acquire().)
-            let _ = comm::recv_one(WaitEnd.swap_unwrap());
+            let _ = comm::recv_one(WaitEnd.take_unwrap());
         }
 
         // This is needed for a failing condition variable to reacquire the
@@ -353,7 +353,7 @@ impl<'self> Condvar<'self> {
                 }
             }
             do check_cvar_bounds(out_of_bounds, condvar_id, "cond.signal_on()") {
-                let queue = queue.swap_unwrap();
+                let queue = queue.take_unwrap();
                 broadcast_waitqueue(&queue)
             }
         }
@@ -1436,7 +1436,7 @@ mod tests {
         do x.write_downgrade |xwrite| {
             let mut xopt = Some(xwrite);
             do y.write_downgrade |_ywrite| {
-                y.downgrade(xopt.swap_unwrap());
+                y.downgrade(xopt.take_unwrap());
                 error!("oops, y.downgrade(x) should have failed!");
             }
         }

src/libextra/treemap.rs

@@ -552,7 +552,7 @@ fn mutate_values<'r, K: TotalOrd, V>(node: &'r mut Option<~TreeNode<K, V>>,
 // Remove left horizontal link by rotating right
 fn skew<K: TotalOrd, V>(node: &mut ~TreeNode<K, V>) {
     if node.left.map_default(false, |x| x.level == node.level) {
-        let mut save = node.left.swap_unwrap();
+        let mut save = node.left.take_unwrap();
         swap(&mut node.left, &mut save.right); // save.right now None
         swap(node, &mut save);
         node.right = Some(save);
@@ -564,7 +564,7 @@ fn skew<K: TotalOrd, V>(node: &mut ~TreeNode<K, V>) {
 fn split<K: TotalOrd, V>(node: &mut ~TreeNode<K, V>) {
     if node.right.map_default(false,
       |x| x.right.map_default(false, |y| y.level == node.level)) {
-        let mut save = node.right.swap_unwrap();
+        let mut save = node.right.take_unwrap();
         swap(&mut node.right, &mut save.left); // save.left now None
         save.level += 1;
         swap(node, &mut save);
@@ -643,7 +643,7 @@ fn remove<K: TotalOrd, V>(node: &mut Option<~TreeNode<K, V>>,
           Equal => {
             if save.left.is_some() {
                 if save.right.is_some() {
-                    let mut left = save.left.swap_unwrap();
+                    let mut left = save.left.take_unwrap();
                     if left.right.is_some() {
                         heir_swap(save, &mut left.right);
                     } else {
@@ -653,13 +653,13 @@ fn remove<K: TotalOrd, V>(node: &mut Option<~TreeNode<K, V>>,
                     save.left = Some(left);
                     (remove(&mut save.left, key), true)
                 } else {
-                    let new = save.left.swap_unwrap();
+                    let new = save.left.take_unwrap();
                     let ~TreeNode{value, _} = replace(save, new);
-                    *save = save.left.swap_unwrap();
+                    *save = save.left.take_unwrap();
                     (Some(value), true)
                 }
             } else if save.right.is_some() {
-                let new = save.right.swap_unwrap();
+                let new = save.right.take_unwrap();
                 let ~TreeNode{value, _} = replace(save, new);
                 (Some(value), true)
             } else {

src/librustc/middle/borrowck/check_loans.rs

@@ -639,25 +639,23 @@ fn check_loans_in_fn<'a>(fk: &visit::fn_kind,
                                 span: span) {
         let cap_vars = this.bccx.capture_map.get(&closure_id);
         for cap_vars.iter().advance |cap_var| {
+            let var_id = ast_util::def_id_of_def(cap_var.def).node;
+            let var_path = @LpVar(var_id);
+            this.check_if_path_is_moved(closure_id, span,
+                                        MovedInCapture, var_path);
             match cap_var.mode {
-                moves::CapRef | moves::CapCopy => {
-                    let var_id = ast_util::def_id_of_def(cap_var.def).node;
-                    let lp = @LpVar(var_id);
-                    this.check_if_path_is_moved(closure_id, span,
-                                                MovedInCapture, lp);
-                }
+                moves::CapRef | moves::CapCopy => {}
                 moves::CapMove => {
-                    check_by_move_capture(this, closure_id, cap_var);
+                    check_by_move_capture(this, closure_id, cap_var, var_path);
                 }
             }
         }
         return;
 
         fn check_by_move_capture(this: @mut CheckLoanCtxt,
                                  closure_id: ast::node_id,
-                                 cap_var: &moves::CaptureVar) {
-            let var_id = ast_util::def_id_of_def(cap_var.def).node;
-            let move_path = @LpVar(var_id);
+                                 cap_var: &moves::CaptureVar,
+                                 move_path: @LoanPath) {
             let move_err = this.analyze_move_out_from(closure_id, move_path);
             match move_err {
                 MoveOk => {}

src/librustc/middle/const_eval.rs

@@ -165,10 +165,58 @@ pub fn classify(e: &expr,
 pub fn lookup_const(tcx: ty::ctxt, e: &expr) -> Option<@expr> {
     match tcx.def_map.find(&e.id) {
         Some(&ast::def_static(def_id, false)) => lookup_const_by_id(tcx, def_id),
+        Some(&ast::def_variant(enum_def, variant_def)) => lookup_variant_by_id(tcx,
+                                                                               enum_def,
+                                                                               variant_def),
         _ => None
     }
 }
 
+pub fn lookup_variant_by_id(tcx: ty::ctxt,
+                            enum_def: ast::def_id,
+                            variant_def: ast::def_id)
+                       -> Option<@expr> {
+    fn variant_expr(variants: &[ast::variant], id: ast::node_id) -> Option<@expr> {
+        for variants.iter().advance |variant| {
+            if variant.node.id == id {
+                return variant.node.disr_expr;
+            }
+        }
+        None
+    }
+
+    if ast_util::is_local(enum_def) {
+        match tcx.items.find(&enum_def.node) {
+            None => None,
+            Some(&ast_map::node_item(it, _)) => match it.node {
+                item_enum(ast::enum_def { variants: ref variants }, _) => {
+                    variant_expr(*variants, variant_def.node)
+                }
+                _ => None
+            },
+            Some(_) => None
+        }
+    } else {
+        let maps = astencode::Maps {
+            root_map: @mut HashMap::new(),
+            method_map: @mut HashMap::new(),
+            vtable_map: @mut HashMap::new(),
+            write_guard_map: @mut HashSet::new(),
+            capture_map: @mut HashMap::new()
+        };
+        match csearch::maybe_get_item_ast(tcx, enum_def,
+            |a, b, c, d| astencode::decode_inlined_item(a, b, maps, /*bar*/ copy c, d)) {
+            csearch::found(ast::ii_item(item)) => match item.node {
+                item_enum(ast::enum_def { variants: ref variants }, _) => {
+                    variant_expr(*variants, variant_def.node)
+                }
+                _ => None
+            },
+            _ => None
+        }
+    }
+}
+
 pub fn lookup_const_by_id(tcx: ty::ctxt,
                           def_id: ast::def_id)
                        -> Option<@expr> {
@@ -237,13 +285,13 @@ pub enum const_val {
 }
 
 pub fn eval_const_expr(tcx: middle::ty::ctxt, e: &expr) -> const_val {
-    match eval_const_expr_partial(tcx, e) {
+    match eval_const_expr_partial(&tcx, e) {
         Ok(r) => r,
         Err(s) => tcx.sess.span_fatal(e.span, s)
     }
 }
 
-pub fn eval_const_expr_partial(tcx: middle::ty::ctxt, e: &expr)
+pub fn eval_const_expr_partial<T: ty::ExprTyProvider>(tcx: &T, e: &expr)
                             -> Result<const_val, ~str> {
     use middle::ty;
     fn fromb(b: bool) -> Result<const_val, ~str> { Ok(const_int(b as i64)) }
@@ -360,7 +408,7 @@ pub fn eval_const_expr_partial(tcx: middle::ty::ctxt, e: &expr)
         }
       }
       expr_cast(base, _) => {
-        let ety = ty::expr_ty(tcx, e);
+        let ety = tcx.expr_ty(e);
         let base = eval_const_expr_partial(tcx, base);
         match /*bad*/copy base {
             Err(_) => base,
@@ -390,8 +438,8 @@ pub fn eval_const_expr_partial(tcx: middle::ty::ctxt, e: &expr)
         }
       }
       expr_path(_) => {
-          match lookup_const(tcx, e) {
-              Some(actual_e) => eval_const_expr_partial(tcx, actual_e),
+          match lookup_const(tcx.ty_ctxt(), e) {
+              Some(actual_e) => eval_const_expr_partial(&tcx.ty_ctxt(), actual_e),
               None => Err(~"Non-constant path in constant expr")
           }
       }

src/librustc/middle/kind.rs

@@ -309,7 +309,7 @@ pub fn check_expr(e: @expr, (cx, v): (Context, visit::vt<Context>)) {
                        "explicit copy requires a copyable argument");
         }
         expr_repeat(element, count_expr, _) => {
-            let count = ty::eval_repeat_count(cx.tcx, count_expr);
+            let count = ty::eval_repeat_count(&cx.tcx, count_expr);
             if count > 1 {
                 let element_ty = ty::expr_ty(cx.tcx, element);
                 check_copy(cx, element_ty, element.span,

src/librustc/middle/trans/tvec.rs

@@ -420,7 +420,7 @@ pub fn write_content(bcx: block,
                     return expr::trans_into(bcx, element, Ignore);
                 }
                 SaveIn(lldest) => {
-                    let count = ty::eval_repeat_count(bcx.tcx(), count_expr);
+                    let count = ty::eval_repeat_count(&bcx.tcx(), count_expr);
                     if count == 0 {
                         return bcx;
                     }
@@ -512,7 +512,7 @@ pub fn elements_required(bcx: block, content_expr: &ast::expr) -> uint {
         },
         ast::expr_vec(ref es, _) => es.len(),
         ast::expr_repeat(_, count_expr, _) => {
-            ty::eval_repeat_count(bcx.tcx(), count_expr)
+            ty::eval_repeat_count(&bcx.tcx(), count_expr)
         }
         _ => bcx.tcx().sess.span_bug(content_expr.span,
                                      "Unexpected evec content")

src/librustc/middle/ty.rs

@@ -4232,42 +4232,57 @@ pub fn normalize_ty(cx: ctxt, t: t) -> t {
     return t_norm;
 }
 
+pub trait ExprTyProvider {
+    pub fn expr_ty(&self, ex: &ast::expr) -> t;
+    pub fn ty_ctxt(&self) -> ctxt;
+}
+
+impl ExprTyProvider for ctxt {
+    pub fn expr_ty(&self, ex: &ast::expr) -> t {
+        expr_ty(*self, ex)
+    }
+
+    pub fn ty_ctxt(&self) -> ctxt {
+        *self
+    }
+}
+
 // Returns the repeat count for a repeating vector expression.
-pub fn eval_repeat_count(tcx: ctxt, count_expr: &ast::expr) -> uint {
+pub fn eval_repeat_count<T: ExprTyProvider>(tcx: &T, count_expr: &ast::expr) -> uint {
     match const_eval::eval_const_expr_partial(tcx, count_expr) {
       Ok(ref const_val) => match *const_val {
         const_eval::const_int(count) => if count < 0 {
-            tcx.sess.span_err(count_expr.span,
-                              "expected positive integer for \
-                               repeat count but found negative integer");
+            tcx.ty_ctxt().sess.span_err(count_expr.span,
+                                        "expected positive integer for \
+                                         repeat count but found negative integer");
             return 0;
         } else {
             return count as uint
         },
         const_eval::const_uint(count) => return count as uint,
         const_eval::const_float(count) => {
-            tcx.sess.span_err(count_expr.span,
-                              "expected positive integer for \
-                               repeat count but found float");
+            tcx.ty_ctxt().sess.span_err(count_expr.span,
+                                        "expected positive integer for \
+                                         repeat count but found float");
             return count as uint;
         }
         const_eval::const_str(_) => {
-            tcx.sess.span_err(count_expr.span,
-                              "expected positive integer for \
-                               repeat count but found string");
+            tcx.ty_ctxt().sess.span_err(count_expr.span,
+                                        "expected positive integer for \
+                                         repeat count but found string");
             return 0;
         }
         const_eval::const_bool(_) => {
-            tcx.sess.span_err(count_expr.span,
-                              "expected positive integer for \
-                               repeat count but found boolean");
+            tcx.ty_ctxt().sess.span_err(count_expr.span,
+                                        "expected positive integer for \
+                                         repeat count but found boolean");
             return 0;
         }
       },
       Err(*) => {
-        tcx.sess.span_err(count_expr.span,
-                          "expected constant integer for repeat count \
-                           but found variable");
+        tcx.ty_ctxt().sess.span_err(count_expr.span,
+                                    "expected constant integer for repeat count \
+                                     but found variable");
         return 0;
       }
     }

src/librustc/middle/typeck/astconv.rs

@@ -479,7 +479,7 @@ pub fn ast_ty_to_ty<AC:AstConv, RS:region_scope + Copy + 'static>(
         }
       }
       ast::ty_fixed_length_vec(ref a_mt, e) => {
-        match const_eval::eval_const_expr_partial(tcx, e) {
+        match const_eval::eval_const_expr_partial(&tcx, e) {
           Ok(ref r) => {
             match *r {
               const_eval::const_int(i) =>