From 98a9cb0b559c0c3ed98321e5e73ab931fcdc17c9 Mon Sep 17 00:00:00 2001
From: Asger F <asgerf@github.com>
Date: Fri, 29 Jul 2022 19:44:10 +0200
Subject: [PATCH] JS: Simplify type hierarchy for SourceNode

The charpred caused spurious type to appear
---
 .../ql/lib/semmle/javascript/dataflow/Sources.qll  | 14 +-------------
 .../RecursionPrevention/SourceNodeRange.expected   |  1 -
 .../RecursionPrevention/SourceNodeRange.ql         | 14 --------------
 3 files changed, 1 insertion(+), 28 deletions(-)
 delete mode 100644 javascript/ql/test/library-tests/RecursionPrevention/SourceNodeRange.expected
 delete mode 100644 javascript/ql/test/library-tests/RecursionPrevention/SourceNodeRange.ql

diff --git a/javascript/ql/lib/semmle/javascript/dataflow/Sources.qll b/javascript/ql/lib/semmle/javascript/dataflow/Sources.qll
index 73d3f9c96ac..8813b974add 100644
--- a/javascript/ql/lib/semmle/javascript/dataflow/Sources.qll
+++ b/javascript/ql/lib/semmle/javascript/dataflow/Sources.qll
@@ -33,13 +33,7 @@ private import semmle.javascript.internal.CachedStages
  * import("fs")
  * ```
  */
-class SourceNode extends DataFlow::Node {
-  SourceNode() {
-    this instanceof SourceNode::Range
-    or
-    none() and this instanceof SourceNode::Internal::RecursionGuard
-  }
-
+class SourceNode extends DataFlow::Node instanceof SourceNode::Range {
   /**
    * Holds if this node flows into `sink` in zero or more local (that is,
    * intra-procedural) steps.
@@ -340,12 +334,6 @@ module SourceNode {
       DataFlow::functionReturnNode(this, _)
     }
   }
-
-  /** INTERNAL. DO NOT USE. */
-  module Internal {
-    /** An empty class that some tests are using to enforce that SourceNode is non-recursive. */
-    abstract class RecursionGuard extends DataFlow::Node { }
-  }
 }
 
 private class NodeModuleSourcesNodes extends SourceNode::Range {
diff --git a/javascript/ql/test/library-tests/RecursionPrevention/SourceNodeRange.expected b/javascript/ql/test/library-tests/RecursionPrevention/SourceNodeRange.expected
deleted file mode 100644
index 59f6fd6e79b..00000000000
--- a/javascript/ql/test/library-tests/RecursionPrevention/SourceNodeRange.expected
+++ /dev/null
@@ -1 +0,0 @@
-| Success |
diff --git a/javascript/ql/test/library-tests/RecursionPrevention/SourceNodeRange.ql b/javascript/ql/test/library-tests/RecursionPrevention/SourceNodeRange.ql
deleted file mode 100644
index 03549a97873..00000000000
--- a/javascript/ql/test/library-tests/RecursionPrevention/SourceNodeRange.ql
+++ /dev/null
@@ -1,14 +0,0 @@
-/**
- * Test that fails to compile if the domain of `SourceNode::Range` depends on `SourceNode` (recursively).
- *
- * This tests adds a negative dependency `SourceNode --!--> SourceNode::Range`
- * so that the undesired edge `SourceNode::Range --> SourceNode` completes a negative cycle.
- */
-
-import javascript
-
-class BadSourceNodeRange extends DataFlow::SourceNode::Internal::RecursionGuard {
-  BadSourceNodeRange() { not this instanceof DataFlow::SourceNode::Range }
-}
-
-select "Success"