[entropy.db.sql] rewrite type checking in insertDependencies()

metadata could be of list type (and not just tuple) in case of
data coming from websrv.

lib/entropy/db/sql.py

@@ -18,7 +18,8 @@ import threading
 
 from entropy.const import etpConst, const_debug_write, \
     const_debug_enabled, const_isunicode, const_convert_to_unicode, \
-    const_get_buffer, const_convert_to_rawstring, const_is_python3
+    const_get_buffer, const_convert_to_rawstring, const_is_python3, \
+    const_get_stringtype
 from entropy.exceptions import SystemDatabaseError, SPMError
 from entropy.spm.plugins.factory import get_default_instance as get_spm
 from entropy.output import bold, red
@@ -1684,12 +1685,14 @@ class EntropySQLRepository(EntropyRepositoryBase):
 
         def insert_list():
             deps = []
+
             for dep in depdata:
                 deptype = 0
-                if isinstance(dep, tuple):
-                    dep, deptype = dep
-                elif isinstance(depdata, dict):
+
+                if isinstance(depdata, dict):
                     deptype = depdata[dep]
+                elif not isinstance(dep, const_get_stringtype()):
+                    dep, deptype = dep
 
                 iddep = self._isDependencyAvailable(dep)
                 if iddep == -1: