Add support for empty column names in composite value types

7 files changed, 107 insertions, 67 deletions

diff --git a/odb/common.cxx b/odb/common.cxx
index 81a416b..667afc0 100644
--- a/odb/common.cxx
+++ b/odb/common.cxx
@@ -496,7 +496,9 @@ traverse_member (semantics::data_member& m, semantics::type& t)
   }
   else
   {
-    string name (column_prefix_ + column_name (m, key_prefix_, default_name_));
+    string name (
+      compose_name (
+        column_prefix_, column_name (m, key_prefix_, default_name_)));
 
     if (traverse_column (m, name, first_))
     {
diff --git a/odb/context.cxx b/odb/context.cxx
index 8335ec4..df94dfb 100644
--- a/odb/context.cxx
+++ b/odb/context.cxx
@@ -897,7 +897,7 @@ column_name (data_member_path const& mp) const
     if (composite_wrapper (utype (m)))
       r += object_columns_base::column_prefix (m);
     else
-      r += column_name (m);
+      r = compose_name (r, column_name (m));
   }
 
   return r;
@@ -928,6 +928,34 @@ column_name (semantics::data_member& m, string const& p, string const& d) const
 }
 
 string context::
+compose_name (string const& prefix, string const& name)
+{
+  string r (prefix);
+  size_t n (r.size ());
+
+  // Add an underscore unless one is already in the prefix or
+  // the name is empty. Similarly, remove it if it is there but
+  // the name is empty.
+  //
+  if (n != 0)
+  {
+    if (r[n - 1] != '_')
+    {
+      if (!name.empty ())
+        r += '_';
+    }
+    else
+    {
+      if (name.empty ())
+        r.resize (n - 1);
+    }
+  }
+
+  r += name;
+  return r;
+}
+
+string context::
 column_type (const data_member_path& mp, string const& kp, bool id)
 {
   if (kp.empty ())
diff --git a/odb/context.hxx b/odb/context.hxx
index e4b9418..f201596 100644
--- a/odb/context.hxx
+++ b/odb/context.hxx
@@ -564,6 +564,11 @@ public:
                string const& key_prefix,
                string const& default_name) const;
 
+  // Compose the name by inserting/removing an underscore, as necessary.
+  //
+  static string
+  compose_name (string const& prefix, string const& name);
+
   string
   column_type (const data_member_path&,
                string const& key_prefix = string (),
diff --git a/odb/relational/common.cxx b/odb/relational/common.cxx
index 1e1009d..3916184 100644
--- a/odb/relational/common.cxx
+++ b/odb/relational/common.cxx
@@ -42,20 +42,23 @@ namespace relational
     // public name.
     //
     string alias;
-
-    if (composite_wrapper (utype ((*id_member (c)))))
     {
-      string p (column_prefix (m, key_prefix_, default_name_));
+      string n;
+
+      if (composite_wrapper (utype (*id_member (c))))
+      {
+        n = column_prefix (m, key_prefix_, default_name_);
 
-      if (p.empty ())
-        p = public_name_db (m);
+        if (n.empty ())
+          n = public_name_db (m);
+        else
+          n.resize (n.size () - 1); // Remove trailing underscore.
+      }
       else
-        p.resize (p.size () - 1); // Remove trailing underscore.
+        n = column_name (m, key_prefix_, default_name_);
 
-      alias = column_prefix_ + p;
+      alias = compose_name (column_prefix_, n);
     }
-    else
-      alias = column_prefix_ + column_name (m, key_prefix_, default_name_);
 
     generate (alias, c);
   }
@@ -219,20 +222,23 @@ namespace relational
       // public name.
       //
       string alias;
-
-      if (composite_wrapper (utype ((*id_member (c)))))
       {
-        string p (column_prefix (m, key_prefix_, default_name_));
+        string n;
+
+        if (composite_wrapper (utype (*id_member (c))))
+        {
+          n = column_prefix (m, key_prefix_, default_name_);
 
-        if (p.empty ())
-          p = public_name_db (m);
+          if (n.empty ())
+            n = public_name_db (m);
+          else
+            n.resize (n.size () - 1); // Remove trailing underscore.
+        }
         else
-          p.resize (p.size () - 1); // Remove trailing underscore.
+          n = column_name (m, key_prefix_, default_name_);
 
-        alias = column_prefix_ + p;
+        alias = compose_name (column_prefix_, n);
       }
-      else
-        alias = column_prefix_ + column_name (m, key_prefix_, default_name_);
 
       string tag (escape (alias + "_alias_tag"));
       string const& fq_name (class_fq_name (c));
@@ -489,8 +495,9 @@ namespace relational
       // Simple id.
       //
       string type (t.fq_name (hint));
-      string column (column_prefix_ +
-                     column_name (m, key_prefix_, default_name_));
+      string column (
+        compose_name (
+          column_prefix_, column_name (m, key_prefix_, default_name_)));
 
       // For pointer_query_columns generate normal column mapping.
       //
diff --git a/odb/relational/model.hxx b/odb/relational/model.hxx
index 6ffffca..b3edd93 100644
--- a/odb/relational/model.hxx
+++ b/odb/relational/model.hxx
@@ -303,15 +303,11 @@ namespace relational
           if (p.empty ())
             p = public_name_db (m);
 
-          name = column_prefix_ + p;
+          name = compose_name (column_prefix_, p);
         }
 
-        // Add an underscore unless we already have one.
-        //
-        if (name[name.size () - 1] != '_')
-          name += '_';
-
-        model_.new_edge<sema_rel::unames> (table_, fk, name + "fk");
+        model_.new_edge<sema_rel::unames> (
+          table_, fk, compose_name (name, "fk"));
       }
 
     protected:
@@ -505,17 +501,14 @@ namespace relational
           // key code above.
           //
           // Note also that id_name can be a column prefix (if id is
-          // composite), in which case it can be empty and if not, then
-          // it will most likely already contain a trailing underscore.
+          // composite), in which case it can be empty. In this case
+          // we just fallback on the default name.
           //
           string id_name (column_name (m, "id", "object_id"));
 
           if (id_name.empty ())
             id_name = "object_id";
 
-          if (id_name[id_name.size () - 1] != '_')
-            id_name += '_';
-
           // Foreign key.
           //
           sema_rel::foreign_key& fk (
@@ -525,7 +518,8 @@ namespace relational
               false, // immediate
               sema_rel::foreign_key::cascade));
           fk.set ("cxx-location", m.location ());
-          model_.new_edge<sema_rel::unames> (t, fk, id_name + "fk");
+          model_.new_edge<sema_rel::unames> (
+            t, fk, compose_name (id_name, "fk"));
 
           // Get referenced columns.
           //
@@ -562,13 +556,16 @@ namespace relational
               id + ".id", sin->type, sin->method, sin->options);
             in->set ("cxx-location", sin->loc);
             model_.new_edge<sema_rel::unames> (
-              t, *in, (sin->name.empty () ? id_name + "i" : sin->name));
+              t,
+              *in,
+              (sin->name.empty () ? compose_name (id_name, "i") : sin->name));
           }
           else
           {
             in = &model_.new_node<sema_rel::index> (id + ".id");
             in->set ("cxx-location", m.location ());
-            model_.new_edge<sema_rel::unames> (t, *in, id_name + "i");
+            model_.new_edge<sema_rel::unames> (
+              t, *in, compose_name (id_name, "i"));
           }
 
           // All the columns we have in this table so far are for the
@@ -594,7 +591,9 @@ namespace relational
           instance<object_columns> oc (model_, t);
           oc->traverse (m, container_it (ct), "index", "index");
 
-          string col_name (column_name (m, "index", "index"));
+          // This is a simple value so the name cannot be empty.
+          //
+          string col (column_name (m, "index", "index"));
 
           // Index. See if we have a custom index.
           //
@@ -609,18 +608,21 @@ namespace relational
               id + ".index", sin->type, sin->method, sin->options);
             in->set ("cxx-location", sin->loc);
             model_.new_edge<sema_rel::unames> (
-              t, *in, (sin->name.empty () ? col_name + "_i" : sin->name));
+              t,
+              *in,
+              (sin->name.empty () ? compose_name (col, "i") : sin->name));
           }
           else
           {
             in = &model_.new_node<sema_rel::index> (id + ".index");
             in->set ("cxx-location", m.location ());
-            model_.new_edge<sema_rel::unames> (t, *in, col_name + "_i");
+            model_.new_edge<sema_rel::unames> (
+              t, *in, compose_name (col, "i"));
           }
 
           model_.new_edge<sema_rel::contains> (
             *in,
-            dynamic_cast<column&> (t.find (col_name)->nameable ()),
+            dynamic_cast<column&> (t.find (col)->nameable ()),
             (sin != 0 ? sin->members.back ().options : ""));
         }
 
diff --git a/odb/relational/processor.cxx b/odb/relational/processor.cxx
index f496a0d..64987a2 100644
--- a/odb/relational/processor.cxx
+++ b/odb/relational/processor.cxx
@@ -2172,13 +2172,7 @@ namespace relational
             if (in.name.empty ())
               in.name = public_name_db (*in.members.front ().path.back ());
 
-            // In case of a composite member, column_name() return a column
-            // prefix which already includes the trailing underscore.
-            //
-            if (in.name[in.name.size () - 1] != '_')
-              in.name += '_';
-
-            in.name += 'i';
+            in.name = compose_name (in.name, "i");
           }
 
           ++i;
diff --git a/odb/relational/source.hxx b/odb/relational/source.hxx
index 2b2c90e..a1f1190 100644
--- a/odb/relational/source.hxx
+++ b/odb/relational/source.hxx
@@ -186,22 +186,21 @@ namespace relational
 
             if (!table_name_.empty ())
             {
+              string n;
+
               if (composite_wrapper (idt))
               {
-                string p (column_prefix (m, key_prefix_, default_name_));
+                n = column_prefix (m, key_prefix_, default_name_);
 
-                if (p.empty ())
-                  p = public_name_db (m);
+                if (n.empty ())
+                  n = public_name_db (m);
                 else
-                  p.resize (p.size () - 1); // Remove trailing underscore.
-
-                table = column_prefix_ + p;
+                  n.resize (n.size () - 1); // Remove trailing underscore.
               }
               else
-                table = column_prefix_ +
-                  column_name (m, key_prefix_, default_name_);
+                n = column_name (m, key_prefix_, default_name_);
 
-              table = quote_id (table);
+              table = quote_id (compose_name (column_prefix_, n));
             }
 
             instance<object_columns> oc (table, sk_, sc_);
@@ -410,7 +409,7 @@ namespace relational
                 tbl = quote_id (i->table);
                 col += tbl;
                 col += '.';
-                col += quote_id (column_name (i->member_path));
+                col += column_qname (i->member_path);
                 break;
               }
             }
@@ -591,20 +590,23 @@ namespace relational
         // fall back on the member's public name.
         //
         string alias;
-
-        if (composite_wrapper (utype (*id_member (c))))
         {
-          string p (column_prefix (m, key_prefix_, default_name_));
+          string n;
+
+          if (composite_wrapper (utype (*id_member (c))))
+          {
+            n = column_prefix (m, key_prefix_, default_name_);
 
-          if (p.empty ())
-            p = public_name_db (m);
+            if (n.empty ())
+              n = public_name_db (m);
+            else
+              n.resize (n.size () - 1); // Remove trailing underscore.
+          }
           else
-            p.resize (p.size () - 1); // Remove trailing underscore.
+            n = column_name (m, key_prefix_, default_name_);
 
-          alias = column_prefix_ + p;
+          alias = compose_name (column_prefix_, n);
         }
-        else
-          alias = column_prefix_ + column_name (m, key_prefix_, default_name_);
 
         semantics::class_* poly_root (polymorphic (c));
         bool poly (poly_root != 0);