C++: Combine the usings tests and add detail about classes.

Author: geoffw0

cpp/ql/test/library-tests/usings/Usings1.expected

@@ -1,7 +1,7 @@
-| templates.cpp:9:5:9:14 | using declaration |
-| usings.cpp:8:1:8:11 | using declaration |
-| usings.cpp:9:1:9:17 | using namespace N |
-| usings.cpp:18:3:18:13 | using declaration |
-| usings.cpp:21:5:21:14 | using declaration |
-| usings.cpp:34:3:34:20 | using declaration |
-| usings.cpp:42:5:42:22 | using declaration |
+| templates.cpp:9:5:9:14 | using declaration | UsingDeclarationEntry, enclosingElement:std |
+| usings.cpp:8:1:8:11 | using declaration | UsingDeclarationEntry, enclosingElement:(global namespace) |
+| usings.cpp:9:1:9:17 | using namespace N | UsingDirectiveEntry, enclosingElement:(global namespace) |
+| usings.cpp:18:3:18:13 | using declaration | UsingDeclarationEntry, enclosingElement:D |
+| usings.cpp:21:5:21:14 | using declaration | UsingDeclarationEntry, enclosingElement:{ ... } |
+| usings.cpp:34:3:34:20 | using declaration | UsingDeclarationEntry, enclosingElement:TD |
+| usings.cpp:42:5:42:22 | using declaration | UsingDeclarationEntry, enclosingElement:nsbar |

cpp/ql/test/library-tests/usings/Usings1.ql

@@ -1,4 +1,14 @@
 import cpp
 
+string describe(UsingEntry ue) {
+  ue instanceof UsingDeclarationEntry and
+  result = "UsingDeclarationEntry"
+  or
+  ue instanceof UsingDirectiveEntry and
+  result = "UsingDirectiveEntry"
+  or
+  result = "enclosingElement:" + ue.getEnclosingElement().toString()
+}
+
 from UsingEntry ue
-select ue
+select ue, concat(describe(ue), ", ")