Merge pull request DOCGroup#1551 from DOCGroup/plm_jira_333

Fix for issue DOCGroup#1550 - empty case evaluation on unions with enum discriminators
iguessthislldo · Jun 16, 2021 · eff3988 · eff3988
2 parents 84438e5 + 9b6353b
commit eff3988
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Showing 2 changed files with 37 additions and 9 deletions.
diff --git a/TAO/TAO_IDL/ast/ast_union_branch.cpp b/TAO/TAO_IDL/ast/ast_union_branch.cpp
@@ -181,22 +181,16 @@ AST_UnionBranch::label_list_length (void)
 void
 AST_UnionBranch::add_labels (AST_Union *u)
 {
+  const bool enum_labels = (u->udisc_type () == AST_Expression::EV_enum);
   for (UTL_LabellistActiveIterator i (this->pd_ll);
        !i.is_done ();
        i.next ())
     {
       if (AST_UnionLabel::UL_default == i.item ()->label_kind ())
         {
-          return;
+          continue;
         }
-    }
-
-  const bool enum_labels = (u->udisc_type () == AST_Expression::EV_enum);
 
-  for (UTL_LabellistActiveIterator i (this->pd_ll);
-       !i.is_done ();
-       i.next ())
-    {
       AST_Expression *ex = i.item ()->label_val ();
       UTL_ScopedName *n = ex->n ();
 

diff --git a/TAO/tests/IDLv4/annotations/annotation_tests.cpp b/TAO/tests/IDLv4/annotations/annotation_tests.cpp
@@ -4,7 +4,9 @@
 #include <ast_porttype.h>
 #include <ast_eventtype.h>
 #include <ast_component.h>
-
+#include <ast_union_branch.h>
+#include <ast_union_label.h>
+#include <ast_expression.h>
 #include <string>
 
 namespace {
@@ -1060,6 +1062,38 @@ annotation_tests ()
       }
   } catch (Failed const &) {}
 
+  /* -------------------------------------------------------------------------
+   * Empty union cases aliasing the default case must always be evaluated
+   * -------------------------------------------------------------------------
+   * When the union has an enum discriminator, and one or more empty cases
+   * acting as an alias to the default case the IDL compiler was failing to
+   * resolve the ordinal value for these empty labels and this causes trouble
+   * for at least OpenDDS.
+   *
+   * This test is designed to verify that the condition is corrected by
+   * parsing a specially crafted union and validating the value of the
+   * label aliasing the default case.
+   */
+  try {
+    Annotation_Test t ("empty union branch label");
+    AST_Union *test_union = t.run (
+               "enum disc {A, B, C};\n"
+               "union empty_union switch (disc) {\n"
+               "case A: long along;\n"
+               "case B: short bshort;\n"
+               "case C:\n"
+               "default: float cfloat;\n"
+               "};\n").assert_node<AST_Union>("::empty_union");
+    AST_Field **af = 0;
+    test_union->field(af, 2);
+    AST_UnionBranch *ub = dynamic_cast<AST_UnionBranch *>(*af);
+    AST_UnionLabel *ul = ub->label ();
+    if (ul->label_val()->ev()->u.ulval != 2)
+      {
+        t.failed("did not get the correct label value");
+      }
+  } catch (Failed const &) {}
+
   // Done, Print Overall Results
   Annotation_Test::results ();
 }