Rust: Move variable consistency check into AstConsistency.qll

Author: hvitved

rust/ql/consistency-queries/VariableConsistency.ql

@@ -73,6 +73,14 @@ query predicate multiplePositions(Element parent, int pos1, int pos2, string acc
   pos1 != pos2
 }
 
+/**
+ * Holds if `va` is a variable access that refers to multiple variables.
+ */
+query predicate multipleVariableTargets(VariableAccess va, Variable v1) {
+  va = v1.getAnAccess() and
+  strictcount(va.getVariable()) > 1
+}
+
 /**
  * Gets counts of abstract syntax tree inconsistencies of each type.
  */
@@ -98,4 +106,7 @@ int getAstInconsistencyCounts(string type) {
   or
   type = "Multiple positions" and
   result = count(Element e | multiplePositions(_, _, _, _, e) | e)
+  or
+  type = "Multiple variable targets" and
+  result = count(VariableAccess va | multipleVariableTargets(va, _) | va)
 }

rust/ql/lib/codeql/rust/internal/AstConsistency.qll

@@ -4,4 +4,5 @@
 | Multiple positions | 0 |
 | Multiple primary QL classes | 0 |
 | Multiple toStrings | 0 |
+| Multiple variable targets | 0 |
 | No location | 0 |