Typestate

src/comp/util/common.rs

@@ -1,10 +1,15 @@
+import std.map;
+import std.map.hashmap;
 import std._uint;
 import std._int;
 import std._vec;
 import std.option.none;
 import front.ast;
 import util.typestate_ann.ts_ann;
 
+import middle.fold;
+import middle.fold.respan;
+
 import std.io.stdout;
 import std.io.str_writer;
 import std.io.string_writer;
@@ -16,6 +21,7 @@ import pretty.pp.mkstate;
 type filename = str;
 type span = rec(uint lo, uint hi);
 type spanned[T] = rec(T node, span span);
+type flag = hashmap[str, ()];
 
 tag ty_mach {
     ty_i8;
@@ -98,9 +104,9 @@ fn uistr(uint i) -> str {
 
 fn elt_expr(&ast.elt e) -> @ast.expr { ret e.expr; }
 
-fn elt_exprs(vec[ast.elt] elts) -> vec[@ast.expr] {
+fn elt_exprs(&vec[ast.elt] elts) -> vec[@ast.expr] {
     auto f = elt_expr;
-    be _vec.map[ast.elt, @ast.expr](f, elts);
+    ret _vec.map[ast.elt, @ast.expr](f, elts);
 }
 
 fn field_expr(&ast.field f) -> @ast.expr { ret f.expr; }
@@ -115,26 +121,41 @@ fn plain_ann() -> ast.ann {
                    none[vec[@middle.ty.t]], none[@ts_ann]);
 }
 
-fn log_expr(&ast.expr e) -> () {
+fn expr_to_str(&ast.expr e) -> str {
   let str_writer s = string_writer();
   auto out_ = mkstate(s.get_writer(), 80u);
   auto out = @rec(s=out_,
                   comments=none[vec[front.lexer.cmnt]],
                   mutable cur_cmnt=0u);
-
   print_expr(out, @e);
-  log(s.get_str());
+  ret s.get_str();
 }
 
-fn log_block(&ast.block b) -> () {
+fn log_expr(&ast.expr e) -> () {
+    log(expr_to_str(e));
+}
+
+fn log_expr_err(&ast.expr e) -> () {
+    log_err(expr_to_str(e));
+}
+
+fn block_to_str(&ast.block b) -> str {
   let str_writer s = string_writer();
   auto out_ = mkstate(s.get_writer(), 80u);
   auto out = @rec(s=out_,
                   comments=none[vec[front.lexer.cmnt]],
                   mutable cur_cmnt=0u);
 
   print_block(out, b);
-  log(s.get_str());
+  ret s.get_str();
+}
+
+fn log_block(&ast.block b) -> () {
+    log(block_to_str(b));
+}
+
+fn log_block_err(&ast.block b) -> () {
+    log_err(block_to_str(b));
 }
 
 fn log_ann(&ast.ann a) -> () {
@@ -148,7 +169,7 @@ fn log_ann(&ast.ann a) -> () {
     }
 }
 
-fn log_stmt(ast.stmt st) -> () {
+fn stmt_to_str(&ast.stmt st) -> str {
   let str_writer s = string_writer();
   auto out_ = mkstate(s.get_writer(), 80u);
   auto out = @rec(s=out_,
@@ -163,9 +184,76 @@ fn log_stmt(ast.stmt st) -> () {
     }
     case (_) { /* do nothing */ }
   }
-  log(s.get_str());
+  ret s.get_str();
 }
 
+fn log_stmt(&ast.stmt st) -> () {
+    log(stmt_to_str(st));
+}
+
+fn log_stmt_err(&ast.stmt st) -> () {
+    log_err(stmt_to_str(st));
+}
+
+fn decl_lhs(@ast.decl d) -> ast.def_id {
+    alt (d.node) {
+        case (ast.decl_local(?l)) {
+            ret l.id;
+        }
+        case (ast.decl_item(?an_item)) {
+            alt (an_item.node) {
+                case (ast.item_const(_,_,_,?d,_)) {
+                    ret d;
+                }
+                case (ast.item_fn(_,_,_,?d,_)) {
+                    ret d;
+                }
+                case (ast.item_mod(_,_,?d)) {
+                    ret d;
+                }
+                case (ast.item_native_mod(_,_,?d)) {
+                    ret d;
+                }
+                case (ast.item_ty(_,_,_,?d,_)) {
+                    ret d;
+                }
+                case (ast.item_tag(_,_,_,?d,_)) {
+                    ret d;
+                }
+                case (ast.item_obj(_,_,_,?d,_)) {
+                    ret d.ctor; /* This doesn't really make sense */
+                }
+            }
+        } 
+    }
+}
+
+fn has_nonlocal_exits(&ast.block b) -> bool {
+    /* overkill, but just passing around a mutable bool doesn't seem
+       to work in rustboot */
+    auto has_exits = new_str_hash[()]();
+
+   fn set_break(&flag f, &span sp, ast.ann a) -> @ast.expr {
+        f.insert("foo", ());
+        ret @respan(sp, ast.expr_break(a));
+    }
+    fn set_cont(&flag f, &span sp, ast.ann a) -> @ast.expr {
+        f.insert("foo", ());
+        ret @respan(sp, ast.expr_cont(a));
+    }
+    fn check_b(&flag f) -> bool {
+        ret (f.size() == 0u);
+    }
+
+    auto fld0 = fold.new_identity_fold[flag]();
+
+    fld0 = @rec(fold_expr_break = bind set_break(_,_,_),
+                fold_expr_cont  = bind set_cont(_,_,_),
+                keep_going      = bind check_b(_) with *fld0);
+    fold.fold_block[flag](has_exits, fld0, b);
+
+    ret (has_exits.size() > 0u);
+}
 //
 // Local Variables:
 // mode: rust

src/comp/util/typestate_ann.rs

@@ -44,6 +44,10 @@ fn empty_poststate(uint num_vars) -> poststate {
   be true_precond(num_vars);
 }
 
+fn false_postcond(uint num_vars) -> postcond {
+    be bitv.create(num_vars, true);
+}
+
 fn empty_pre_post(uint num_vars) -> pre_and_post {
   ret(rec(precondition=empty_prestate(num_vars),
           postcondition=empty_poststate(num_vars)));
@@ -119,7 +123,7 @@ fn set_postcondition(&ts_ann a, &postcond p) -> () {
 
 // Sets all the bits in a's prestate to equal the
 // corresponding bit in p's prestate.
-fn set_prestate(&ts_ann a, &prestate p) -> bool {
+fn set_prestate(@ts_ann a, &prestate p) -> bool {
   ret bitv.copy(a.states.prestate, p);
 }
 
@@ -139,6 +143,13 @@ fn extend_poststate(&poststate p, &poststate new) -> bool {
   ret bitv.union(p, new);
 }
 
+// Clears the given bit in p
+fn relax_prestate(uint i, &prestate p) -> bool {
+    auto was_set = bitv.get(p, i);
+    bitv.set(p, i, false);
+    ret was_set;
+}
+
 fn ann_precond(&ts_ann a) -> precond {
   ret a.conditions.precondition;
 }
@@ -148,8 +159,12 @@ fn ann_prestate(&ts_ann a) -> prestate {
 }
 
 fn pp_clone(&pre_and_post p) -> pre_and_post {
-  ret rec(precondition=bitv.clone(p.precondition),
-          postcondition=bitv.clone(p.postcondition));
+  ret rec(precondition=clone(p.precondition),
+          postcondition=clone(p.postcondition));
+}
+
+fn clone(prestate p) -> prestate {
+    ret bitv.clone(p);
 }
 
 // returns true if a implies b

src/lib/_vec.rs

@@ -280,6 +280,21 @@ fn plus_option[T](&vec[T] v, &option.t[T] o) -> () {
     }
 }
 
+fn cat_options[T](&vec[option.t[T]] v) -> vec[T] {
+    let vec[T] res = vec();
+
+    for (option.t[T] o in v) {
+        alt (o) {
+            case (none[T]) { }
+            case (some[T](?t)) {
+                res += vec(t);
+            }
+        }
+    }
+
+    ret res;
+}
+
 // TODO: Remove in favor of built-in "freeze" operation when it's implemented.
 fn freeze[T](vec[mutable T] v) -> vec[T] {
     let vec[T] result = vec();

src/test/compile-fail/break-uninit.rs

@@ -0,0 +1,22 @@
+// xfail-boot
+// xfail-stage0
+// error-pattern:Unsatisfied precondition
+
+fn foo() -> int {
+  let int x;
+  let int i;
+
+  do {
+    i = 0;
+    break;
+    x = 0;
+  } while ((x = 0) != 0);
+
+  log(x);
+
+  ret 17;
+}
+
+fn main() {
+  log(foo());
+}

src/test/compile-fail/break-uninit2.rs

@@ -0,0 +1,22 @@
+// xfail-boot
+// xfail-stage0
+// error-pattern:Unsatisfied precondition
+
+fn foo() -> int {
+  let int x;
+  let int i;
+
+  do {
+    i = 0;
+    break;
+    x = 0;
+  } while (1 != 2);
+
+  log(x);
+
+  ret 17;
+}
+
+fn main() {
+  log(foo());
+}

src/test/run-pass/use-uninit-alt.rs

@@ -0,0 +1,21 @@
+fn foo[T](&myoption[T] o) -> int {
+  let int x = 5;
+
+  alt (o) {
+    case (none[T]) { }
+    case (some[T](?t)) {
+      x += 1;
+    }
+  }
+
+  ret x;
+}
+
+tag myoption[T] {
+  none;
+  some(T);
+}
+
+fn main() {
+  log(5);
+}

src/test/run-pass/use-uninit-alt2.rs

@@ -0,0 +1,21 @@
+fn foo[T](&myoption[T] o) -> int {
+  let int x;
+
+  alt (o) {
+    case (none[T]) { fail; }
+    case (some[T](?t)) {
+      x = 5;
+    }
+  }
+
+  ret x;
+}
+
+tag myoption[T] {
+  none;
+  some(T);
+}
+
+fn main() {
+  log(5);
+}