Python: Fix false positive for cyclic imports guarded by if False:.

Author: taus-semmle

python/ql/src/Imports/Cyclic.qll

@@ -22,7 +22,8 @@ predicate circular_import(ModuleValue m1, ModuleValue m2) {
 ModuleValue stmt_imports(ImportingStmt s) {
     exists(string name |
         result.importedAs(name) and not name = "__main__" |
-        name = s.getAnImportedModuleName()
+        name = s.getAnImportedModuleName() and
+        s.getASubExpression().pointsTo(result)
     )
 }
 

python/ql/test/query-tests/Imports/cyclic-module/module10.py

@@ -1,5 +1,9 @@
+from typing import TYPE_CHECKING
 
 if False:
     import module1
 
+if TYPE_CHECKING:
+    import module1
+
 x = 1

python/ql/test/query-tests/Imports/cyclic-module/typing.py

@@ -0,0 +1,2 @@
+TYPE_CHECKING = False
+