C#: Re-factor NeutralCallable to include all neutrals and introduce NeutralSummaryCallable. Also include printing of the neutral kind in FlowSummaries testcase.

Author: michaelnebel

csharp/ql/lib/semmle/code/csharp/dataflow/internal/FlowSummaryImpl.qll

@@ -296,11 +296,21 @@ module Public {
     predicate hasProvenance(Provenance provenance) { provenance = "manual" }
   }
 
-  /** A callable where there is no flow via the callable. */
-  class NeutralCallable extends SummarizedCallableBase {
+  /**
+   * A callable where there is no flow via the callable.
+   */
+  class NeutralSummaryCallable extends NeutralCallable {
+    NeutralSummaryCallable() { this.getKind() = "summary" }
+  }
+
+  /**
+   * A callable that has a neutral model.
+   */
+  class NeutralCallable extends NeutralCallableBase {
+    private string kind;
     private Provenance provenance;
 
-    NeutralCallable() { neutralSummaryElement(this, provenance) }
+    NeutralCallable() { neutralElement(this, kind, provenance) }
 
     /**
      * Holds if the neutral is auto generated.
@@ -316,6 +326,11 @@ module Public {
      * Holds if the neutral has provenance `p`.
      */
     predicate hasProvenance(Provenance p) { p = provenance }
+
+    /**
+     * Gets the kind of the neutral.
+     */
+    string getKind() { result = kind }
   }
 }
 
@@ -1318,6 +1333,8 @@ module Private {
       /** Gets the string representation of this callable used by `neutral/1`. */
       abstract string getCallableCsv();
 
+      string getKind() { result = super.getKind() }
+
       string toString() { result = super.toString() }
     }
 
@@ -1364,6 +1381,7 @@ module Private {
       exists(RelevantNeutralCallable c |
         csv =
           c.getCallableCsv() // Callable information
+            + c.getKind() + ";" // kind
             + renderProvenanceNeutral(c) // provenance
       )
     }

csharp/ql/lib/semmle/code/csharp/dataflow/internal/FlowSummaryImplSpecific.qll

@@ -15,9 +15,15 @@ private import semmle.code.csharp.Unification
 private import semmle.code.csharp.dataflow.ExternalFlow
 private import semmle.code.csharp.dataflow.FlowSummary as FlowSummary
 
-class SummarizedCallableBase extends Callable {
-  SummarizedCallableBase() { this.isUnboundDeclaration() }
-}
+/**
+ * A class of callables that are candidates for flow summary modeling.
+ */
+class SummarizedCallableBase = UnboundCallable;
+
+/**
+ * A class of callables that are candidates for neutral modeling.
+ */
+class NeutralCallableBase = UnboundCallable;
 
 /**
  * A module for importing frameworks that define synthetic globals.
@@ -120,12 +126,12 @@ predicate summaryElement(Callable c, string input, string output, string kind, s
 }
 
 /**
- * Holds if a neutral summary model exists for `c` with provenance `provenace`,
- * which means that there is no flow through `c`.
+ * Holds if a neutral model exists for `c` of kind `kind`
+ * and with provenance `provenance`.
  */
-predicate neutralSummaryElement(Callable c, string provenance) {
+predicate neutralElement(Callable c, string kind, string provenance) {
   exists(string namespace, string type, string name, string signature |
-    neutralModel(namespace, type, name, signature, "summary", provenance) and
+    neutralModel(namespace, type, name, signature, kind, provenance) and
     c = interpretElement(namespace, type, false, name, signature, "")
   )
 }