From 455c35b512895c19bf922c2b804d750d27cb8dbd Mon Sep 17 00:00:00 2001
From: Simon Willison <swillison@gmail.com>
Date: Mon, 8 May 2023 13:52:21 -0700
Subject: [PATCH] .convert(skip_false) option, refs #527

---
 sqlite_utils/db.py    |  3 ++-
 tests/test_convert.py | 10 ++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/sqlite_utils/db.py b/sqlite_utils/db.py
index 44d59da..3c5d91a 100644
--- a/sqlite_utils/db.py
+++ b/sqlite_utils/db.py
@@ -2618,6 +2618,7 @@ class Table(Queryable):
         where: Optional[str] = None,
         where_args: Optional[Union[Iterable, dict]] = None,
         show_progress: bool = False,
+        skip_false: bool = True,
     ):
         """
         Apply conversion function ``fn`` to every value in the specified columns.
@@ -2660,7 +2661,7 @@ class Table(Queryable):
 
             def convert_value(v):
                 bar.update(1)
-                if not v:
+                if skip_false and not v:
                     return v
                 return jsonify_if_needed(fn(v))
 
diff --git a/tests/test_convert.py b/tests/test_convert.py
index 31a9d28..9fd29c3 100644
--- a/tests/test_convert.py
+++ b/tests/test_convert.py
@@ -50,6 +50,16 @@ def test_convert_where(fresh_db, where, where_args):
     assert list(table.rows) == [{"id": 1, "title": "One"}, {"id": 2, "title": "TWO"}]
 
 
+def test_convert_skip_false(fresh_db):
+    table = fresh_db["table"]
+    table.insert_all([{"x": 0}, {"x": 1}])
+    assert table.get(1)["x"] == 0
+    assert table.get(2)["x"] == 1
+    table.convert("x", lambda x: x + 1, skip_false=False)
+    assert table.get(1)["x"] == 1
+    assert table.get(2)["x"] == 2
+
+
 @pytest.mark.parametrize(
     "drop,expected",
     (