Auto-fix: Add support for 'use_while_loops'

Author: HugoGGuerrier

lkql_checker/share/lkql/use_while_loops.lkql

@@ -1,5 +1,27 @@
+import stdlib
+
+fun replace_by_while_loop(simple_loop, ctx) =
+    |" Replace the given ``simple_loop`` with an exit condition as first
+    |" statement with a while loop.
+    {
+        val negated_exit_cond = match simple_loop.f_stmts[1].f_cond_expr
+        | null => new Identifier("False")
+        | op@(RelationOp | UnOp(f_op: OpNot)) => stdlib.negate_op(op)
+        | e => new UnOp(new OpNot(), e);
+        ctx.remove(simple_loop.f_stmts[1])
+           .replace(
+               simple_loop,
+               new WhileLoopStmt(
+                   f_spec=new WhileLoopSpec(negated_exit_cond),
+                   f_stmts=simple_loop.f_stmts,
+                   f_end_name=simple_loop.f_end_name
+               )
+           )
+    }
+
 @check(message="simple LOOP may be replaced by a WHILE loop",
-       category="Style", subcategory="Programming Practice")
+       category="Style", subcategory="Programming Practice",
+       auto_fix=replace_by_while_loop)
 fun use_while_loops(node) =
     |" Flag simple loop statements that have the exit statement completing
     |" execution of such a loop as the first statement in their sequence of

testsuite/tests/checks/use_while_loops/test.out

@@ -16,3 +16,30 @@ loop1.adb:28:4: rule violation: simple LOOP may be replaced by a WHILE loop
 30 ||    end loop Local_Loop;
    ||_______________________^
 
+Patched "loop1.adb":
+====================
+
+procedure Loop1 (Str : in out String) is
+   J : Integer;
+begin
+   J := 0;
+   while J <=10 loop if Str (J) = ' ' then
+         Str (J) := 'a';
+         return;
+      end if;
+
+      J := J + 1;
+   end loop;loop           --  NOFLAG
+      null;
+   end loop;
+
+   Outer_Loop:
+   loop           --  NOFLAG
+      loop        --  NOFLAG
+         exit Outer_Loop when True;
+      end loop;
+   end loop Outer_Loop;
+
+   Local_Loop:
+   while False loop end loop Local_Loop;end Loop1;
+

testsuite/tests/checks/use_while_loops/test.yaml

@@ -1,3 +1,4 @@
 driver: 'checker'
 rule_name: use_while_loops
 project: 'prj.gpr'
+auto_fix: True