Scope: Address logic flaw creating multiple parents

We adjust the parent scope explicitly for loops, if statements and
switch statements, but, due to a logic bug, we previously retained
the existing results provided by Element.getParentScope().

Author: lcartey

cpp/common/src/codingstandards/cpp/Scope.qll

@@ -38,10 +38,9 @@ module Internal {
     or
     exists(SwitchStmt switchStmt | switchStmt.getStmt() = e and result = switchStmt)
     or
-    not result.(Loop).getStmt() = e and
-    not result.(IfStmt).getThen() = e and
-    not result.(IfStmt).getElse() = e and
-    not result.(SwitchStmt).getStmt() = e and
+    not exists(Loop loop | loop.getStmt() = e) and
+    not exists(IfStmt ifStmt | ifStmt.getThen() = e or ifStmt.getElse() = e) and
+    not exists(SwitchStmt switchStmt | switchStmt.getStmt() = e) and
     if exists(e.getParentScope())
     then result = e.getParentScope()
     else (

cpp/common/test/library/codingstandards/cpp/scope/ParentScope.expected

@@ -33,7 +33,6 @@
 | test.cpp:11:25:11:25 | 1 | test.cpp:10:28:34:3 | { ... } |
 | test.cpp:11:28:11:30 | id1 | test.cpp:10:28:34:3 | { ... } |
 | test.cpp:11:28:11:32 | ... ++ | test.cpp:10:28:34:3 | { ... } |
-| test.cpp:11:35:33:5 | { ... } | test.cpp:10:28:34:3 | { ... } |
 | test.cpp:11:35:33:5 | { ... } | test.cpp:11:5:33:5 | for(...;...;...) ... |
 | test.cpp:12:7:32:7 | for(...;...;...) ... | test.cpp:11:35:33:5 | { ... } |
 | test.cpp:12:12:12:19 | declaration | test.cpp:11:35:33:5 | { ... } |
@@ -43,7 +42,6 @@
 | test.cpp:12:27:12:27 | 1 | test.cpp:11:35:33:5 | { ... } |
 | test.cpp:12:30:12:32 | id1 | test.cpp:11:35:33:5 | { ... } |
 | test.cpp:12:30:12:34 | ... ++ | test.cpp:11:35:33:5 | { ... } |
-| test.cpp:12:37:32:7 | { ... } | test.cpp:11:35:33:5 | { ... } |
 | test.cpp:12:37:32:7 | { ... } | test.cpp:12:7:32:7 | for(...;...;...) ... |
 | test.cpp:13:9:31:9 | { ... } | test.cpp:12:37:32:7 | { ... } |
 | test.cpp:14:11:14:18 | declaration | test.cpp:13:9:31:9 | { ... } |
@@ -52,17 +50,14 @@
 | test.cpp:16:15:16:17 | id1 | test.cpp:13:9:31:9 | { ... } |
 | test.cpp:16:15:16:22 | ... == ... | test.cpp:13:9:31:9 | { ... } |
 | test.cpp:16:22:16:22 | 0 | test.cpp:13:9:31:9 | { ... } |
-| test.cpp:16:25:18:11 | { ... } | test.cpp:13:9:31:9 | { ... } |
 | test.cpp:16:25:18:11 | { ... } | test.cpp:16:11:20:11 | if (...) ...  |
 | test.cpp:17:13:17:20 | declaration | test.cpp:16:25:18:11 | { ... } |
 | test.cpp:17:17:17:19 | id1 | test.cpp:16:25:18:11 | { ... } |
-| test.cpp:18:18:20:11 | { ... } | test.cpp:13:9:31:9 | { ... } |
 | test.cpp:18:18:20:11 | { ... } | test.cpp:16:11:20:11 | if (...) ...  |
 | test.cpp:19:13:19:20 | declaration | test.cpp:18:18:20:11 | { ... } |
 | test.cpp:19:17:19:19 | id1 | test.cpp:18:18:20:11 | { ... } |
 | test.cpp:21:11:25:11 | switch (...) ...  | test.cpp:13:9:31:9 | { ... } |
 | test.cpp:21:19:21:21 | id1 | test.cpp:13:9:31:9 | { ... } |
-| test.cpp:21:24:25:11 | { ... } | test.cpp:13:9:31:9 | { ... } |
 | test.cpp:21:24:25:11 | { ... } | test.cpp:21:11:25:11 | switch (...) ...  |
 | test.cpp:22:11:22:17 | case ...: | test.cpp:21:24:25:11 | { ... } |
 | test.cpp:22:16:22:16 | 0 | test.cpp:21:24:25:11 | { ... } |