fix the arity of predicate aliases

Author: erik-krogh

ql/src/codeql_ql/ast/Ast.qll

@@ -154,7 +154,14 @@ class Predicate extends TPredicate, AstNode {
   /**
    * Gets the number of parameters.
    */
-  int getArity() { result = count(getParameter(_)) }
+  int getArity() {
+    not this.(ClasslessPredicate).getAlias() instanceof PredicateExpr and
+    result = count(getParameter(_))
+    or
+    exists(PredicateExpr alias | alias = this.(ClasslessPredicate).getAlias() |
+      result = alias.getArity()
+    )
+  }
 
   /**
    * Gets the return type (if any) of the predicate.

ql/src/codeql_ql/ast/internal/Predicate.qll

@@ -240,6 +240,7 @@ module PredConsistency {
   query predicate noResolveCall(Call c) {
     not resolveCall(c, _) and
     not c instanceof NoneCall and
+    not c instanceof AnyCall and
     not c.getLocation().getFile().getAbsolutePath().regexpMatch(".*/(test|examples)/.*")
   }
 

ql/test/callgraph/Foo.qll

@@ -15,3 +15,19 @@ class Sub extends Foo {
 }
 
 query predicate test2() { any(Foo f).bar() }
+
+module Aliases {
+  predicate myThing2(int i, int j) { i = 2 and j = 3 }
+
+  predicate myThing0() { any() }
+
+  predicate alias0 = myThing0/0;
+
+  predicate alias2 = myThing2/2;
+
+  query predicate test3() {
+    alias2(3, 4) // doesn't work.
+    or
+    alias0() // <- works
+  }
+}

ql/test/callgraph/callgraph.expected

@@ -2,3 +2,7 @@
 | Foo.qll:10:21:10:25 | PredicateCall | Foo.qll:8:3:8:28 | ClassPredicate |
 | Foo.qll:14:30:14:40 | MemberCall | Foo.qll:10:3:10:27 | ClassPredicate |
 | Foo.qll:17:27:17:42 | MemberCall | Foo.qll:8:3:8:28 | ClassPredicate |
+| Foo.qll:29:5:29:16 | PredicateCall | Foo.qll:20:3:20:54 | myThing2 |
+| Foo.qll:29:5:29:16 | PredicateCall | Foo.qll:26:3:26:32 | alias2 |
+| Foo.qll:31:5:31:12 | PredicateCall | Foo.qll:22:3:22:32 | myThing0 |
+| Foo.qll:31:5:31:12 | PredicateCall | Foo.qll:24:3:24:32 | alias0 |