Python: Port UninitializedLocal.ql

Uses the new ExceptionTypes machinery. No test changes.

python/ql/lib/semmle/python/dataflow/new/internal/DataFlowDispatch.qll

@@ -2322,6 +2322,11 @@ module ExceptionTypes {
     BaseException() { name = "BaseException" }
   }
 
+  /** The builtin `NameError` exception type. */
+  class NameError extends BuiltinExceptType {
+    NameError() { name = "NameError" }
+  }
+
   /**
    * Holds if the exception edge from `r` to `handler` is unlikely because
    * none of the exception types that `r` may raise are handled by `handler`.

python/ql/src/Variables/UninitializedLocal.ql

@@ -12,7 +12,7 @@
  */
 
 import python
-private import LegacyPointsTo
+private import semmle.python.dataflow.new.internal.DataFlowDispatch
 import Undefined
 
 predicate uninitialized_local(NameNode use) {
@@ -21,16 +21,16 @@ predicate uninitialized_local(NameNode use) {
   ) and
   (
     any(Uninitialized uninit).taints(use) and
-    PointsToInternal::reachableBlock(use.getBasicBlock(), _)
+    Reachability::likelyReachable(use.getBasicBlock())
     or
     not exists(EssaVariable var | var.getASourceUse() = use)
   )
 }
 
 predicate explicitly_guarded(NameNode u) {
-  exists(Try t |
+  exists(Try t, ExceptionTypes::NameError nameError |
     t.getBody().contains(u.getNode()) and
-    t.getAHandler().getType().(ExprWithPointsTo).pointsTo(ClassValue::nameError())
+    nameError.getAUse().asExpr() = t.getAHandler().getType()
   )
 }