From: Daniele Varrazzo <daniele.varrazzo@gmail.com>
Date: Tue, 21 Sep 2021 15:55:52 +0000 (+0100)
Subject: Raise a friendly exception if None is passed to register_*()
X-Git-Tag: 3.0~73
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=97c64f57c5de7fe30b3c5cccae2822851cb3840a;p=thirdparty%2Fpsycopg.git

Raise a friendly exception if None is passed to register_*()

The most likely cause is fetching info and the object is not found.
Suggest that that's what happened instead of throwing an AttributeError
or anything else random.
---

diff --git a/psycopg/psycopg/types/composite.py b/psycopg/psycopg/types/composite.py
index 7a754dc40..c80111875 100644
--- a/psycopg/psycopg/types/composite.py
+++ b/psycopg/psycopg/types/composite.py
@@ -217,6 +217,13 @@ def register_composite(
         the composite into a Python object.
     """
 
+    # A friendly error warning instead of an AttributeError in case fetch()
+    # failed and it wasn't noticed.
+    if not info:
+        raise TypeError(
+            "no info passed. Is the requested composite available?"
+        )
+
     # Register arrays and type info
     info.register(context)
 
diff --git a/psycopg/psycopg/types/hstore.py b/psycopg/psycopg/types/hstore.py
index f39bec47a..e45b9414f 100644
--- a/psycopg/psycopg/types/hstore.py
+++ b/psycopg/psycopg/types/hstore.py
@@ -107,6 +107,10 @@ def register_hstore(
     :param context: The context where to register the adapters. If `!None`,
         register it globally.
     """
+    # A friendly error warning instead of an AttributeError in case fetch()
+    # failed and it wasn't noticed.
+    if not info:
+        raise TypeError("no info passed. Is the 'hstore' extension loaded?")
 
     # Register arrays and type info
     info.register(context)
diff --git a/psycopg/psycopg/types/range.py b/psycopg/psycopg/types/range.py
index 6c353b5e5..59fa04dd3 100644
--- a/psycopg/psycopg/types/range.py
+++ b/psycopg/psycopg/types/range.py
@@ -442,6 +442,10 @@ def register_range(
     Register loaders so that loading data of this type will result in a `Range`
     with bounds parsed as the right subtype.
     """
+    # A friendly error warning instead of an AttributeError in case fetch()
+    # failed and it wasn't noticed.
+    if not info:
+        raise TypeError("no info passed. Is the requested range available?")
 
     # Register arrays and type info
     info.register(context)
diff --git a/tests/types/test_composite.py b/tests/types/test_composite.py
index cfc2c91e3..cb1125754 100644
--- a/tests/types/test_composite.py
+++ b/tests/types/test_composite.py
@@ -327,3 +327,8 @@ def test_callable_dumper_not_registered(conn, testcomp):
     # but the loader is registered
     cur = conn.execute("select '(foo,42,3.14)'::testcomp")
     assert cur.fetchone()[0] == ("foo", 42, 3.14, 3.14)
+
+
+def test_no_info_error(conn):
+    with pytest.raises(TypeError, match="composite"):
+        register_composite(None, conn)
diff --git a/tests/types/test_hstore.py b/tests/types/test_hstore.py
index 5c951548f..337d12a32 100644
--- a/tests/types/test_hstore.py
+++ b/tests/types/test_hstore.py
@@ -97,3 +97,8 @@ def test_roundtrip_array(hstore, conn):
     register_hstore(TypeInfo.fetch(conn, "hstore"), conn)
     samp1 = conn.execute("select %s", (samp,)).fetchone()[0]
     assert samp1 == samp
+
+
+def test_no_info_error(conn):
+    with pytest.raises(TypeError, match="hstore.*extension"):
+        register_hstore(None, conn)
diff --git a/tests/types/test_range.py b/tests/types/test_range.py
index 9ed018c15..2860cac8f 100644
--- a/tests/types/test_range.py
+++ b/tests/types/test_range.py
@@ -667,3 +667,8 @@ class TestRangeObject:
         expected = "[2010-01-01 00:00:00-05:00, 2011-01-01 00:00:00-05:00)"
         result = str(r)
         assert result == expected
+
+
+def test_no_info_error(conn):
+    with pytest.raises(TypeError, match="range"):
+        register_range(None, conn)