From: Daniele Varrazzo <daniele.varrazzo@gmail.com>
Date: Tue, 14 Dec 2021 21:45:22 +0000 (+0100)
Subject: Fix Cursor.rowcount after an executemany hitting no result
X-Git-Tag: pool-3.1~74
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1b2829f91ba1809af00e913e24ee0d59f7c984f6;p=thirdparty%2Fpsycopg.git

Fix Cursor.rowcount after an executemany hitting no result

Close #178
---

diff --git a/docs/news.rst b/docs/news.rst
index db6e3bf5b..bb70910ba 100644
--- a/docs/news.rst
+++ b/docs/news.rst
@@ -19,6 +19,8 @@ Psycopg 3.0.7 (unreleased)
 
 - Fix crash in `~Cursor.executemany()` with no input sequence
   (:ticket:`#179`).
+- Fix wrong `~Cursor.rowcount` after an `~Cursor.executemany()` returning no
+  rows (:ticket:`#178`).
 
 
 Current release
diff --git a/psycopg/psycopg/cursor.py b/psycopg/psycopg/cursor.py
index 03db0a50b..ee3559510 100644
--- a/psycopg/psycopg/cursor.py
+++ b/psycopg/psycopg/cursor.py
@@ -231,7 +231,7 @@ class BaseCursor(Generic[ConnectionType, Row]):
         # Override rowcout for the first result. Calls to nextset() will change
         # it to the value of that result only, but we hope nobody will notice.
         # You haven't read this comment.
-        self._rowcount = nrows or -1
+        self._rowcount = nrows
         self._last_query = query
 
         for cmd in self._conn._prepared.get_maintenance_commands():
diff --git a/tests/test_cursor.py b/tests/test_cursor.py
index 42c8bed37..c4a4da872 100644
--- a/tests/test_cursor.py
+++ b/tests/test_cursor.py
@@ -291,6 +291,18 @@ def test_executemany_returning_rowcount(conn, execmany):
     assert cur.rowcount == 2
 
 
+def test_executemany_rowcount_no_hit(conn, execmany):
+    cur = conn.cursor()
+    cur.executemany("delete from execmany where id = %s", [(-1,), (-2,)])
+    assert cur.rowcount == 0
+    cur.executemany("delete from execmany where id = %s", [])
+    assert cur.rowcount == 0
+    cur.executemany(
+        "delete from execmany where id = %s returning num", [(-1,), (-2,)]
+    )
+    assert cur.rowcount == 0
+
+
 @pytest.mark.parametrize(
     "query",
     [
diff --git a/tests/test_cursor_async.py b/tests/test_cursor_async.py
index ef92692c6..dd9009b49 100644
--- a/tests/test_cursor_async.py
+++ b/tests/test_cursor_async.py
@@ -292,6 +292,18 @@ async def test_executemany_returning_rowcount(aconn, execmany):
     assert cur.rowcount == 2
 
 
+async def test_executemany_rowcount_no_hit(aconn, execmany):
+    cur = aconn.cursor()
+    await cur.executemany("delete from execmany where id = %s", [(-1,), (-2,)])
+    assert cur.rowcount == 0
+    await cur.executemany("delete from execmany where id = %s", [])
+    assert cur.rowcount == 0
+    await cur.executemany(
+        "delete from execmany where id = %s returning num", [(-1,), (-2,)]
+    )
+    assert cur.rowcount == 0
+
+
 @pytest.mark.parametrize(
     "query",
     [