Make all self nodes LocalSourceNodes

Author: hvitved

ruby/ql/lib/codeql/ruby/dataflow/internal/DataFlowPrivate.qll

@@ -236,7 +236,7 @@ private module Cached {
     // for `self`. At that point, the `self`s returned by `trackInstance`
     // in `DataFlowDispatch.qll` should refer to the post-update node,
     // and we can remove this case.
-    n instanceof SelfArgumentNode
+    n.asExpr().getExpr() instanceof Self
     or
     not localFlowStepTypeTracker+(any(Node e |
         e instanceof ExprNode

ruby/ql/test/library-tests/modules/callgraph.expected

@@ -2,6 +2,8 @@ getTarget
 | calls.rb:2:5:2:14 | call to puts | calls.rb:87:5:87:17 | puts |
 | calls.rb:5:1:5:3 | call to foo | calls.rb:1:1:3:3 | foo |
 | calls.rb:5:1:5:3 | call to foo | calls.rb:71:1:75:3 | foo |
+| calls.rb:8:5:8:14 | call to puts | calls.rb:87:5:87:17 | puts |
+| calls.rb:11:1:11:8 | call to bar | calls.rb:7:1:9:3 | bar |
 | calls.rb:13:1:13:8 | call to foo | calls.rb:1:1:3:3 | foo |
 | calls.rb:13:1:13:8 | call to foo | calls.rb:71:1:75:3 | foo |
 | calls.rb:22:5:22:15 | call to singleton_m | calls.rb:17:5:17:29 | singleton_m |
@@ -84,8 +86,6 @@ getTarget
 | private.rb:28:1:28:12 | call to public | private.rb:5:3:6:5 | public |
 | private.rb:30:1:30:15 | call to private_on_main | private.rb:21:1:22:3 | private_on_main |
 unresolvedCall
-| calls.rb:8:5:8:14 | call to puts |
-| calls.rb:11:1:11:8 | call to bar |
 | calls.rb:19:5:19:14 | call to instance_m |
 | calls.rb:20:5:20:19 | call to instance_m |
 | calls.rb:26:1:26:12 | call to instance_m |