Fix the StopIteration issue in Python 3.7 (#971)

* Fix the StopIteration issue in Python 3.7

changelog.rst

@@ -8,6 +8,7 @@ Bug fixes:
 * Set default port in `connect_uri` when none is given. (Thanks: `Daniel Egger`_)
 * Fix for error listing databases (#951). (Thanks: `Irina Truong`_)
 * Enable Ctrl-Z to suspend the app (Thanks: `Amjith Ramanujam`_).
+* Fix StopIteration exception raised at runtime for Python 3.7 (Thanks: `Amjith Ramanujam`_).
 
 Internal:
 ---------

pgcli/packages/parseutils/tables.py

@@ -36,11 +36,11 @@ def extract_from_part(parsed, stop_at_punctuation=True):
                 for x in extract_from_part(item, stop_at_punctuation):
                     yield x
             elif stop_at_punctuation and item.ttype is Punctuation:
-                raise StopIteration
+                return
             # An incomplete nested select won't be recognized correctly as a
             # sub-select. eg: 'SELECT * FROM (SELECT id FROM user'. This causes
             # the second FROM to trigger this elif condition resulting in a
-            # StopIteration. So we need to ignore the keyword if the keyword
+            # `return`. So we need to ignore the keyword if the keyword
             # FROM.
             # Also 'SELECT * FROM abc JOIN def' will trigger this elif
             # condition. So we need to ignore the keyword JOIN and its variants
@@ -93,7 +93,7 @@ def extract_table_identifiers(token_stream, allow_functions=True):
             name = name.lower()
         return schema_name, name, alias
 
-
+    try:
         for item in token_stream:
             if isinstance(item, IdentifierList):
                 for identifier in item.get_identifiers():
@@ -117,6 +117,8 @@ def extract_table_identifiers(token_stream, allow_functions=True):
             elif isinstance(item, Function):
                 schema_name, real_name, alias = parse_identifier(item)
                 yield TableReference(None, real_name, alias, allow_functions)
+    except StopIteration:
+        return
 
 
 # extract_tables is inspired from examples in the sqlparse lib.