Fix issue #21630 - non-static range foreach ignores enum and alias

Author: Bolpat

compiler/src/dmd/parse.d

@@ -5575,6 +5575,7 @@ class Parser(AST, Lexer = dmd.lexer.Lexer) : Lexer
         }
 
         TOK op = token.value;
+        Loc aliasOrEnumLoc;
 
         nextToken();
         check(TOK.leftParenthesis);
@@ -5617,10 +5618,12 @@ class Parser(AST, Lexer = dmd.lexer.Lexer) : Lexer
 
                 case TOK.enum_:
                     stc = STC.manifest;
+                    aliasOrEnumLoc = token.loc;
                     goto Lagain;
 
                 case TOK.alias_:
                     storageClass = appendStorageClass(storageClass, STC.alias_);
+                    aliasOrEnumLoc = token.loc;
                     nextToken();
                     break;
 
@@ -5705,6 +5708,16 @@ class Parser(AST, Lexer = dmd.lexer.Lexer) : Lexer
             AST.Expression upr = parseExpression();
             check(TOK.rightParenthesis);
             Loc endloc;
+            if (is(Foreach == AST.Statement) && (p.storageClass & STC.alias_))
+            {
+                error(aliasOrEnumLoc, "cannot use `alias` with a range `foreach`");
+                eSink.errorSupplemental(aliasOrEnumLoc, "use `static foreach` instead");
+            }
+            if (is(Foreach == AST.Statement) && (p.storageClass & STC.manifest))
+            {
+                error(aliasOrEnumLoc, "cannot use `enum` with a range `foreach`");
+                eSink.errorSupplemental(aliasOrEnumLoc, "use `static foreach` instead");
+            }
             static if (is(Foreach == AST.Statement) || is(Foreach == AST.StaticForeachStatement))
             {
                 AST.Statement _body = parseStatement(0, null, &endloc);

compiler/test/fail_compilation/issue21630.d

@@ -0,0 +1,18 @@
+/+
+TEST_OUTPUT:
+---
+fail_compilation/issue21630.d(14): Error: cannot use `enum` with a range `foreach`
+fail_compilation/issue21630.d(15): Error: cannot use `alias` with a range `foreach`
+fail_compilation/issue21630.d(16): Error: cannot use `enum` with a range `foreach`
+fail_compilation/issue21630.d(17): Error: cannot use `alias` with a range `foreach`
+---
++/
+
+void main()
+{
+    enum a = [1, 2, 3];
+    foreach(enum i; a) { } // error
+    foreach(alias i; a) { } // error
+    foreach(enum i; 0 .. 3) {  } // error
+    foreach(alias i; 0 .. 3) {  } // error
+}