Merge pull request #5183 from AndrejMitrovic/fix-12558

Issue 12558 - Deprecate implicit catch statements
dlang · Jul 7, 2016 · 18e6844 · 18e6844
2 parents dd717cd + 9ebcbed
commit 18e6844
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Showing 6 changed files with 62 additions and 14 deletions.
diff --git a/src/func.d b/src/func.d
@@ -357,7 +357,7 @@ public:
              *      // equivalent with:
              *      //    s->body; scope(exit) nrvo_var->edtor;
              * as:
-             *      try { s->body; } catch(__o) { nrvo_var->edtor; throw __o; }
+             *      try { s->body; } catch(Throwable __o) { nrvo_var->edtor; throw __o; }
              *      // equivalent with:
              *      //    s->body; scope(failure) nrvo_var->edtor;
              */
@@ -373,7 +373,7 @@ public:
             }
 
             auto catches = new Catches();
-            auto ctch = new Catch(Loc(), null, id, handler);
+            auto ctch = new Catch(Loc(), getThrowable(), id, handler);
             ctch.internalCatch = true;
             ctch.semantic(sc); // Run semantic to resolve identifier '__o'
             catches.push(ctch);
@@ -3799,13 +3799,13 @@ extern (C++) class FuncDeclaration : Declaration
                 //printf("fdv->frequire: %s\n", fdv->frequire->toChars());
                 /* Make the call:
                  *   try { __require(); }
-                 *   catch { frequire; }
+                 *   catch (Throwable) { frequire; }
                  */
                 Expression eresult = null;
                 Expression e = new CallExp(loc, new VarExp(loc, fdv.fdrequire, false), eresult);
                 Statement s2 = new ExpStatement(loc, e);
 
-                auto c = new Catch(loc, null, null, sf);
+                auto c = new Catch(loc, getThrowable(), null, sf);
                 c.internalCatch = true;
                 auto catches = new Catches();
                 catches.push(c);

diff --git a/src/statement.d b/src/statement.d
@@ -90,6 +90,15 @@ Expression checkAssignmentAsCondition(Expression e)
     return e;
 }
 
+/// Return a type identifier reference to 'object.Throwable'
+TypeIdentifier getThrowable()
+{
+    auto tid = new TypeIdentifier(Loc(), Id.empty);
+    tid.addIdent(Id.object);
+    tid.addIdent(Id.Throwable);
+    return tid;
+}
+
 enum BE : int
 {
     BEnone = 0,
@@ -2295,7 +2304,7 @@ extern (C++) final class Catch : RootObject
 
     Catch syntaxCopy()
     {
-        auto c = new Catch(loc, type ? type.syntaxCopy() : null, ident, (handler ? handler.syntaxCopy() : null));
+        auto c = new Catch(loc, type ? type.syntaxCopy() : getThrowable(), ident, (handler ? handler.syntaxCopy() : null));
         c.internalCatch = internalCatch;
         return c;
     }

diff --git a/src/statementsem.d b/src/statementsem.d
@@ -194,7 +194,7 @@ private extern (C++) final class StatementSemanticVisitor : Visitor
                             }
 
                             auto catches = new Catches();
-                            auto ctch = new Catch(Loc(), null, id, handler);
+                            auto ctch = new Catch(Loc(), getThrowable(), id, handler);
                             ctch.internalCatch = true;
                             catches.push(ctch);
 
@@ -3441,11 +3441,11 @@ void semantic(Catch c, Scope* sc)
 
     if (!c.type)
     {
+        deprecation(c.loc, "catch statement without an exception " ~
+            "specification is deprecated; use catch(Throwable) for old behavior");
+
         // reference .object.Throwable
-        auto tid = new TypeIdentifier(Loc(), Id.empty);
-        tid.addIdent(Id.object);
-        tid.addIdent(Id.Throwable);
-        c.type = tid;
+        c.type = getThrowable();
     }
     c.type = c.type.semantic(c.loc, sc);
     if (c.type == Type.terror)

diff --git a/test/compilable/test12558.d b/test/compilable/test12558.d
@@ -0,0 +1,39 @@
+// REQUIRED_ARGS:
+/*
+TEST_OUTPUT:
+---
+compilable/test12558.d(16): Deprecation: catch statement without an exception specification is deprecated; use catch(Throwable) for old behavior
+compilable/test12558.d(21): Deprecation: catch statement without an exception specification is deprecated; use catch(Throwable) for old behavior
+---
+*/
+
+void main()
+{
+    auto handler = () { };
+
+    try {
+        assert(0);
+    } catch
+        handler();
+
+    try {
+        assert(0);
+    } catch {
+        handler();
+    }
+
+    // ensure diagnostics are not emitted for verioned-out blocks
+    version (none)
+    {
+        try {
+            assert(0);
+        } catch  // should not emit diagnostics
+            handler();
+
+        try {
+            assert(0);
+        } catch {  // ditto
+            handler();
+        }
+    }
+}
diff --git a/test/fail_compilation/fail23.d b/test/fail_compilation/fail23.d
@@ -13,7 +13,7 @@ void main()
     {
         break;
     }
-    catch
+    catch (Throwable)
     {
     }
 }
diff --git a/test/fail_compilation/fail2456.d b/test/fail_compilation/fail2456.d
@@ -93,18 +93,18 @@ void test2456b()
     scope(success)
     {
         try {}
-        catch {}    // NG
+        catch (Throwable) {}    // NG
     }
 
     scope(failure)
     {
         try {}
-        catch {}    // OK
+        catch (Throwable) {}    // OK
     }
 
     scope(exit)
     {
         try {}
-        catch {}    // NG
+        catch (Throwable) {}    // NG
     }
 }