fix: close Array.add_line output before the closing bracket

tests/test_items.py

@@ -529,6 +529,19 @@ def test_array_add_line() -> None:
     )
 
 
+def test_array_add_line_closes_the_last_line() -> None:
+    t = api.array()
+    t.add_line("foo", comment="bar")
+
+    assert (
+        t.as_string()
+        == """[
+    \"foo\", # bar
+]"""
+    )
+    assert parse(f"array = {t.as_string()}").unwrap() == {"array": ["foo"]}
+
+
 def test_array_add_line_multiline_comment_is_rejected() -> None:
     t = api.array()
     with pytest.raises(ValueError, match="line breaks"):

tomlkit/items.py

@@ -1547,6 +1547,15 @@ def add_line(
             new_values.append(
                 Comment(Trivia(indent=indent, comment=f"# {comment}", trail=""))
             )
+
+        if (
+            self._value
+            and self._value[-1].is_whitespace()
+            and self._value[-1].indent is not None
+            and self._value[-1].indent.s == "\n"
+        ):
+            self._value.pop()
+
         list.extend(self, data_values)
         if len(self._value) > 0:
             last_item = self._value[-1]
@@ -1566,6 +1575,8 @@ def add_line(
                 self._value.extend(self._group_values(new_values))
         else:
             self._value.extend(self._group_values(new_values))
+        if newline and (items or comment):
+            self._value.extend(self._group_values([Whitespace("\n")]))
         self._reindex()
 
     def clear(self) -> None: