Issue 12228 - Deprecate usage of 'this' and 'super' as types

dlang · May 31, 2018 · 3905312 · 3905312
1 parent c3993f9
commit 3905312
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Showing 19 changed files with 90 additions and 30 deletions.
diff --git a/changelog/deprecate_this_super_as_types.dd b/changelog/deprecate_this_super_as_types.dd
@@ -0,0 +1,33 @@
+Deprecate usage of `this` and `super` as types
+
+Prior to this release, `this` and `super` could be used as both data or types
+depending on the context.  Starting with this release using `this` or `super`
+as a type will result in a compiler error.
+
+---
+class C
+{
+    shared(this) x;    // Deprecation: Using `this` as a type is deprecated. Use `typeof(this)` instead
+}
+
+class D : C
+{
+    shared(super) a;   // Deprecation: Using `super` as a type is deprecated. Use `typeof(super)` instead
+    super b;           // Deprecation: Using `super` as a type is deprecated. Use `typeof(super)` instead
+}
+---
+
+Use `typeof(super)` or `typeof(this)` instead.
+
+---
+class C
+{
+    shared(typeof(this)) x;
+}
+
+class D : C
+{
+    shared(typeof(super)) a;
+    typeof(super) b;
+}
+---
diff --git a/src/dmd/apply.d b/src/dmd/apply.d
@@ -29,7 +29,7 @@ import dmd.visitor;
  */
 private extern (C++) final class PostorderExpressionVisitor : StoppableVisitor
 {
-    alias visit = super.visit;
+    alias visit = typeof(super).visit;
 public:
     StoppableVisitor v;
 

diff --git a/src/dmd/canthrow.d b/src/dmd/canthrow.d
@@ -39,7 +39,7 @@ extern (C++) bool canThrow(Expression e, FuncDeclaration func, bool mustNotThrow
     // stop walking if we determine this expression can throw
     extern (C++) final class CanThrow : StoppableVisitor
     {
-        alias visit = super.visit;
+        alias visit = typeof(super).visit;
         FuncDeclaration func;
         bool mustNotThrow;
 

diff --git a/src/dmd/delegatize.d b/src/dmd/delegatize.d
@@ -82,7 +82,7 @@ private void lambdaSetParent(Expression e, FuncDeclaration fd)
 {
     extern (C++) final class LambdaSetParent : StoppableVisitor
     {
-        alias visit = super.visit;
+        alias visit = typeof(super).visit;
         FuncDeclaration fd;
 
     public:
@@ -137,7 +137,7 @@ extern (C++) bool lambdaCheckForNestedRef(Expression e, Scope* sc)
 {
     extern (C++) final class LambdaCheckForNestedRef : StoppableVisitor
     {
-        alias visit = super.visit;
+        alias visit = typeof(super).visit;
     public:
         Scope* sc;
         bool result;

diff --git a/src/dmd/dinterpret.d b/src/dmd/dinterpret.d
@@ -261,7 +261,7 @@ struct CompiledCtfeFunction
     {
         extern (C++) final class VarWalker : StoppableVisitor
         {
-            alias visit = super.visit;
+            alias visit = typeof(super).visit;
         public:
             CompiledCtfeFunction* ccf;
 

diff --git a/src/dmd/expression.d b/src/dmd/expression.d
@@ -7061,7 +7061,7 @@ extern (C++) final class CondExp : BinExp
     {
         extern (C++) final class DtorVisitor : StoppableVisitor
         {
-            alias visit = super.visit;
+            alias visit = typeof(super).visit;
         public:
             Scope* sc;
             CondExp ce;

diff --git a/src/dmd/func.d b/src/dmd/func.d
@@ -68,7 +68,7 @@ enum BUILTIN : int
  */
 extern (C++) final class NrvoWalker : StatementRewriteWalker
 {
-    alias visit = super.visit;
+    alias visit = typeof(super).visit;
 public:
     FuncDeclaration fd;
     Scope* sc;
@@ -3174,7 +3174,7 @@ extern (C++) final class FuncLiteralDeclaration : FuncDeclaration
 
         extern (C++) final class RetWalker : StatementRewriteWalker
         {
-            alias visit = super.visit;
+            alias visit = typeof(super).visit;
         public:
             Scope* sc;
             Type tret;

diff --git a/src/dmd/inlinecost.d b/src/dmd/inlinecost.d
@@ -287,7 +287,7 @@ public:
         {
             extern (C++) final class LambdaInlineCost : StoppableVisitor
             {
-                alias visit = super.visit;
+                alias visit = typeof(super).visit;
                 InlineCostVisitor icv;
 
             public:

diff --git a/src/dmd/nogc.d b/src/dmd/nogc.d
@@ -29,7 +29,7 @@ import dmd.visitor;
  */
 extern (C++) final class NOGCVisitor : StoppableVisitor
 {
-    alias visit = super.visit;
+    alias visit = typeof(super).visit;
 public:
     FuncDeclaration f;
     bool err;

diff --git a/src/dmd/parse.d b/src/dmd/parse.d
@@ -2872,11 +2872,6 @@ final class Parser(AST) : Lexer
                     }
                 default:
                     {
-                        // Deprecated in 2018-04.
-                        // Change to error in 2019-04.
-                        // @@@DEPRECATED_2019-04@@@.
-                        if (token.value == TOK.this_)
-                            deprecation("`this` cannot be used as a parameter type. Use `typeof(this)` instead");
                         stc = storageClass & (AST.STC.in_ | AST.STC.out_ | AST.STC.ref_ | AST.STC.lazy_);
                         // if stc is not a power of 2
                         if (stc & (stc - 1) && !(stc == (AST.STC.in_ | AST.STC.ref_)))

diff --git a/src/dmd/sapply.d b/src/dmd/sapply.d
@@ -27,7 +27,7 @@ import dmd.visitor;
  */
 extern (C++) final class PostorderStatementVisitor : StoppableVisitor
 {
-    alias visit = super.visit;
+    alias visit = typeof(super).visit;
 public:
     StoppableVisitor v;
 

diff --git a/src/dmd/sideeffect.d b/src/dmd/sideeffect.d
@@ -35,7 +35,7 @@ extern (C++) bool isTrivialExp(Expression e)
 {
     extern (C++) final class IsTrivialExp : StoppableVisitor
     {
-        alias visit = super.visit;
+        alias visit = typeof(super).visit;
     public:
         extern (D) this()
         {
@@ -68,7 +68,7 @@ extern (C++) bool hasSideEffect(Expression e)
 {
     extern (C++) final class LambdaHasSideEffect : StoppableVisitor
     {
-        alias visit = super.visit;
+        alias visit = typeof(super).visit;
     public:
         extern (D) this()
         {

diff --git a/src/dmd/statement.d b/src/dmd/statement.d
@@ -176,7 +176,7 @@ extern (C++) abstract class Statement : RootObject
     {
         extern (C++) final class UsesEH : StoppableVisitor
         {
-            alias visit = super.visit;
+            alias visit = typeof(super).visit;
         public:
             override void visit(Statement s)
             {
@@ -215,7 +215,7 @@ extern (C++) abstract class Statement : RootObject
     {
         extern (C++) final class ComeFrom : StoppableVisitor
         {
-            alias visit = super.visit;
+            alias visit = typeof(super).visit;
         public:
             override void visit(Statement s)
             {
@@ -254,7 +254,7 @@ extern (C++) abstract class Statement : RootObject
     {
         extern (C++) final class HasCode : StoppableVisitor
         {
-            alias visit = super.visit;
+            alias visit = typeof(super).visit;
         public:
             override void visit(Statement s)
             {

diff --git a/src/dmd/typesem.d b/src/dmd/typesem.d
@@ -1510,7 +1510,7 @@ extern(C++) Expression getProperty(Type t, const ref Loc loc, Identifier ident,
 
 private extern (C++) final class GetPropertyVisitor : Visitor
 {
-    alias visit = super.visit;
+    alias visit = typeof(super).visit;
     Loc loc;
     Identifier ident;
     int flag;
@@ -2056,7 +2056,7 @@ extern(C++) void resolve(Type mt, const ref Loc loc, Scope* sc, Expression* pe,
 
 private extern(C++) final class ResolveVisitor : Visitor
 {
-    alias visit = super.visit;
+    alias visit = typeof(super).visit;
     Loc loc;
     Scope* sc;
     Expression* pe;
@@ -2238,6 +2238,16 @@ private extern(C++) final class ResolveVisitor : Visitor
         //printf("TypeIdentifier::resolve(sc = %p, idents = '%s')\n", sc, mt.toChars());
         if ((mt.ident.equals(Id._super) || mt.ident.equals(Id.This)) && !hasThis(sc))
         {
+            // @@@DEPRECATED_v2.086@@@.
+            if (mt.ident.equals(Id._super))
+            {
+                deprecation(mt.loc, "Using `super` as a type is deprecated. Use `typeof(super)` instead");
+            }
+            // @@@DEPRECATED_v2.086@@@.
+            if (mt.ident.equals(Id.This))
+            {
+                deprecation(mt.loc, "Using `this` as a type is deprecated. Use `typeof(this)` instead");
+            }
             AggregateDeclaration ad = sc.getStructClassScope();
             if (ad)
             {
@@ -2549,7 +2559,7 @@ extern(C++) Expression dotExp(Type mt, Scope* sc, Expression e, Identifier ident
 
 private extern(C++) final class DotExpVisitor : Visitor
 {
-    alias visit = super.visit;
+    alias visit = typeof(super).visit;
     Scope *sc;
     Expression e;
     Identifier ident;

diff --git a/test/compilable/test15785.d b/test/compilable/test15785.d
@@ -18,5 +18,5 @@ class Derived : Base, IBase2
         // IBase2.faz(); // doesn't work yet due to a bug in checkAccess
     }
 
-    super.T t;
+    typeof(super).T t;
 }
diff --git a/test/fail_compilation/fail18228.d b/test/fail_compilation/fail18228.d
@@ -2,8 +2,8 @@
 /*
 TEST_OUTPUT:
 ---
-fail_compilation/fail18228.d(12): Deprecation: `this` cannot be used as a parameter type. Use `typeof(this)` instead
-fail_compilation/fail18228.d(13): Deprecation: `this` cannot be used as a parameter type. Use `typeof(this)` instead
+fail_compilation/fail18228.d(12): Deprecation: Using `this` as a type is deprecated. Use `typeof(this)` instead
+fail_compilation/fail18228.d(13): Deprecation: Using `this` as a type is deprecated. Use `typeof(this)` instead
 ---
 */
 

diff --git a/test/fail_compilation/test12228.d b/test/fail_compilation/test12228.d
@@ -0,0 +1,22 @@
+/*
+REQUIRED_ARGS: -de
+TEST_OUTPUT:
+---
+fail_compilation/test12228.d(14): Deprecation: Using `this` as a type is deprecated. Use `typeof(this)` instead
+fail_compilation/test12228.d(19): Error: no property `x` for type `object.Object`
+fail_compilation/test12228.d(20): Deprecation: Using `super` as a type is deprecated. Use `typeof(super)` instead
+fail_compilation/test12228.d(21): Deprecation: Using `super` as a type is deprecated. Use `typeof(super)` instead
+---
+*/
+
+class C
+{
+    shared(this) x;
+}
+
+class D : C
+{
+    alias x = typeof(super).x;
+    shared(super) a;
+    super b;
+}
diff --git a/test/fail_compilation/test13867.d b/test/fail_compilation/test13867.d
@@ -15,14 +15,14 @@ extern (C++) class Y : Base {
     override void blah(){}
 }
 class Z : Base {
-    alias blah = super.blah;
+    alias blah = typeof(super).blah;
     override void blah(){}//Error
 }
 class O : Base {
     extern (C++) override void blah(){}
 }
 extern (C++) class OK : Base {
-    alias blah = super.blah;
+    alias blah = typeof(super).blah;
     override void blah(){}
 }
 

diff --git a/test/fail_compilation/test15785b.d b/test/fail_compilation/test15785b.d
@@ -12,7 +12,7 @@ import imports.test15785;
 
 class Derived : Base, IBase2
 {
-    super.T t;
+    typeof(super).T t;
     Base.T t2;
     IBase2.T t3;
 }