From fef9727cce1f73b1ab3b307d3577d32f8b6ced1f Mon Sep 17 00:00:00 2001
From: Daniele Varrazzo <daniele.varrazzo@gmail.com>
Date: Sun, 26 Sep 2010 21:59:54 +0100
Subject: [PATCH] parse_hstore converted in class method.

---
 lib/extras.py         | 86 ++++++++++++++++++++++---------------------
 tests/types_extras.py |  7 ++--
 2 files changed, 48 insertions(+), 45 deletions(-)

diff --git a/lib/extras.py b/lib/extras.py
index 4b20bb64..7bfede5e 100644
--- a/lib/extras.py
+++ b/lib/extras.py
@@ -35,7 +35,7 @@ try:
 except:
     logging = None
 
-from psycopg2 import DATETIME, DataError, InterfaceError
+import psycopg2
 from psycopg2 import extensions as _ext
 from psycopg2.extensions import cursor as _cursor
 from psycopg2.extensions import connection as _connection
@@ -515,55 +515,57 @@ class HstoreAdapter(object):
         v.prepare(self.conn)
         return "hstore(%s, %s)" % (k.getquoted(), v.getquoted())
 
-_re_hstore = regex.compile(r"""
-    # hstore key:
-    "( # catch in quotes
-        (?: # many of
-            [^"] # either not a quote
-            # or a quote escaped, i.e. preceded by an odd number of backslashes
-            | [^\\] (?:\\\\)* \\"
-        )*
-    )"
-    \s*=>\s* # hstore value
-    (?:
-        NULL # the value can be null - not catched
-        # or the same quoted string of the key
-        | "((?:[^"] | [^\\] (?:\\\\)* \\" )*)"
-    )
-    (?:\s*,\s*|$) # pairs separated by comma or end of string.
-""", regex.VERBOSE)
+    _re_hstore = regex.compile(r"""
+        # hstore key:
+        "( # catch in quotes
+            (?: # many of
+                [^"] # either not a quote
+                # or a quote escaped, i.e. preceded by an odd number of backslashes
+                | [^\\] (?:\\\\)* \\"
+            )*
+        )"
+        \s*=>\s* # hstore value
+        (?:
+            NULL # the value can be null - not catched
+            # or the same quoted string of the key
+            | "((?:[^"] | [^\\] (?:\\\\)* \\" )*)"
+        )
+        (?:\s*,\s*|$) # pairs separated by comma or end of string.
+    """, regex.VERBOSE)
 
-def parse_hstore(s, cur):
-    """Parse an hstore representation in a Python string.
+    def parse(self, s, cur):
+        """Parse an hstore representation in a Python string.
 
-    The hstore is represented as something like::
+        The hstore is represented as something like::
 
-        "a"=>"1", "b"=>"2"
+            "a"=>"1", "b"=>"2"
 
-    with backslash-escaped strings.
-    """
-    if s is None:
-        return None
+        with backslash-escaped strings.
+        """
+        if s is None:
+            return None
 
-    rv = {}
-    start = 0
-    for m in _re_hstore.finditer(s):
-        if m is None or m.start() != start:
-            raise InterfaceError(
-                "error parsing hstore pair at char %d" % start)
-        k = m.group(1).decode("string_escape")
-        v = m.group(2)
-        if v is not None:
-            v = v.decode("string_escape")
+        rv = {}
+        start = 0
+        for m in self._re_hstore.finditer(s):
+            if m is None or m.start() != start:
+                raise psycopg2.InterfaceError(
+                    "error parsing hstore pair at char %d" % start)
+            k = m.group(1).decode("string_escape")
+            v = m.group(2)
+            if v is not None:
+                v = v.decode("string_escape")
 
-        rv[k] = v
-        start = m.end()
+            rv[k] = v
+            start = m.end()
 
-    if start < len(s):
-        raise InterfaceError(
-            "error parsing hstore: unparsed data after char %d" % start)
+        if start < len(s):
+            raise psycopg2.InterfaceError(
+                "error parsing hstore: unparsed data after char %d" % start)
 
-    return rv
+        return rv
+
+    parse = classmethod(parse)
 
 
 __all__ = filter(lambda k: not k.startswith('_'), locals().keys())
diff --git a/tests/types_extras.py b/tests/types_extras.py
index 559e6950..480312ba 100644
--- a/tests/types_extras.py
+++ b/tests/types_extras.py
@@ -158,10 +158,10 @@ class HstoreTestCase(unittest.TestCase):
         self.assertEqual(ii[3], ("E'd'", "E'%s'" % encc))
 
     def test_parse(self):
-        from psycopg2.extras import parse_hstore
+        from psycopg2.extras import HstoreAdapter
 
         def ok(s, d):
-            self.assertEqual(parse_hstore(s, None), d)
+            self.assertEqual(HstoreAdapter.parse(s, None), d)
 
         ok(None, None)
         ok('', {})
@@ -176,7 +176,8 @@ class HstoreTestCase(unittest.TestCase):
         ok(r'"a\\\\\""=>"1"', {r'a\\"': '1'})
 
         def ko(s):
-            self.assertRaises(psycopg2.InterfaceError, parse_hstore, s, None)
+            self.assertRaises(psycopg2.InterfaceError,
+                HstoreAdapter.parse, s, None)
 
         ko('a')
         ko('"a"')