CPP: Clean up duplication in Adding365DaysPerYear.ql.

Author: geoffw0

cpp/ql/src/Likely Bugs/Leap Year/LeapYear.qll

@@ -258,22 +258,33 @@ class PossibleYearArithmeticOperationCheckConfiguration extends DataFlow::Config
   }
 
   override predicate isSource(DataFlow::Node source) {
-    exists( Expr e, Operation op |
-      e = source.asExpr() |
-      op.getAChild*().getValue().toInt()=365
-      and op.getAChild*() = e
-       )
+    exists(Operation op |
+      op = source.asExpr() |
+      op.getAChild*().getValue().toInt() = 365 and
+      not op.getParent() instanceof Expr
+    )
   }
- 
+
+  override predicate isAdditionalFlowStep(DataFlow::Node node1, DataFlow::Node node2) {
+    // flow from anything on the RHS of an assignment to a time/date structure to that
+    // assignment.
+    exists(StructLikeClass dds, FieldAccess fa, AssignExpr aexpr, Expr e |
+      e = node1.asExpr() and
+      aexpr = node2.asExpr() |
+      (dds instanceof FileTimeStruct or dds instanceof DateDataStruct)
+      and fa.getQualifier().getUnderlyingType() = dds
+      and aexpr.getLValue() = fa
+      and aexpr.getRValue().getAChild*() = e
+    )
+  }
+
   override predicate isSink(DataFlow::Node sink) {
-    exists( StructLikeClass dds, FieldAccess fa, AssignExpr aexpr, Expr e |
-       e = sink.asExpr() |
-         (dds instanceof FileTimeStruct
-           or dds instanceof DateDataStruct)
-        and fa.getQualifier().getUnderlyingType() = dds
-        and fa.isModified()
-        and aexpr.getAChild() = fa
-        and aexpr.getChild(1).getAChild*() = e
+    exists(StructLikeClass dds, FieldAccess fa, AssignExpr aexpr |
+      aexpr = sink.asExpr() |
+      (dds instanceof FileTimeStruct or dds instanceof DateDataStruct)
+      and fa.getQualifier().getUnderlyingType() = dds
+      and fa.isModified()
+      and aexpr.getLValue() = fa
     )
   }
 }

cpp/ql/test/query-tests/Likely Bugs/Leap Year/Adding365DaysPerYear/Adding365daysPerYear.expected

@@ -1,5 +1,3 @@
-| test.cpp:173:29:173:38 | qwLongTime | This arithmetic operation $@ uses a constant value of 365 ends up modifying the date/time located at $@, without considering leap year scenarios. | test.cpp:170:2:170:47 | ... += ... | ... += ... | test.cpp:173:29:173:38 | qwLongTime | qwLongTime |
-| test.cpp:174:30:174:39 | qwLongTime | This arithmetic operation $@ uses a constant value of 365 ends up modifying the date/time located at $@, without considering leap year scenarios. | test.cpp:170:2:170:47 | ... += ... | ... += ... | test.cpp:174:30:174:39 | qwLongTime | qwLongTime |
-| test.cpp:193:15:193:18 | days | This arithmetic operation $@ uses a constant value of 365 ends up modifying the date/time located at $@, without considering leap year scenarios. | test.cpp:193:15:193:18 | days | days | test.cpp:193:15:193:18 | days | days |
-| test.cpp:193:15:193:24 | ... / ... | This arithmetic operation $@ uses a constant value of 365 ends up modifying the date/time located at $@, without considering leap year scenarios. | test.cpp:193:15:193:24 | ... / ... | ... / ... | test.cpp:193:15:193:24 | ... / ... | ... / ... |
-| test.cpp:193:22:193:24 | 365 | This arithmetic operation $@ uses a constant value of 365 ends up modifying the date/time located at $@, without considering leap year scenarios. | test.cpp:193:22:193:24 | 365 | 365 | test.cpp:193:22:193:24 | 365 | 365 |
+| test.cpp:173:2:173:52 | ... = ... | This arithmetic operation $@ uses a constant value of 365 ends up modifying the date/time located at $@, without considering leap year scenarios. | test.cpp:170:2:170:47 | ... += ... | ... += ... | test.cpp:173:2:173:52 | ... = ... | ... = ... |
+| test.cpp:174:2:174:46 | ... = ... | This arithmetic operation $@ uses a constant value of 365 ends up modifying the date/time located at $@, without considering leap year scenarios. | test.cpp:170:2:170:47 | ... += ... | ... += ... | test.cpp:174:2:174:46 | ... = ... | ... = ... |
+| test.cpp:193:2:193:24 | ... = ... | This arithmetic operation $@ uses a constant value of 365 ends up modifying the date/time located at $@, without considering leap year scenarios. | test.cpp:193:2:193:24 | ... = ... | ... = ... | test.cpp:193:2:193:24 | ... = ... | ... = ... |