Allow ui.update_slider to handle non-numeric values

e2e/bugs/0648-update-slider-datetime-value/app.py

@@ -0,0 +1,34 @@
+import datetime
+
+from shiny import App, Inputs, Outputs, Session, reactive, render, ui
+
+start_time = datetime.datetime(2023, 7, 1, 0, 0, 0, 0, tzinfo=datetime.timezone.utc)
+end_time = start_time + datetime.timedelta(hours=1)
+
+app_ui = ui.page_fluid(
+    ui.input_slider(
+        "times",
+        "Times",
+        start_time,
+        end_time,
+        start_time,
+        time_format="%H:%M:%S",
+    ),
+    ui.output_text_verbatim("txt"),
+    ui.input_action_button("reset", "Jump to end"),
+)
+
+
+def server(input: Inputs, output: Outputs, session: Session):
+    @output
+    @render.text
+    def txt():
+        return input.times()
+
+    @reactive.Effect
+    @reactive.event(input.reset)
+    def reset_time():
+        ui.update_slider("times", value=end_time)
+
+
+app = App(app_ui, server)

e2e/bugs/0648-update-slider-datetime-value/test_update_slider_datetime_value.py

@@ -0,0 +1,14 @@
+from conftest import ShinyAppProc
+from controls import InputActionButton, OutputTextVerbatim
+from playwright.sync_api import Page
+
+
+def test_slider_app(page: Page, local_app: ShinyAppProc) -> None:
+    page.goto(local_app.url)
+
+    btn_reset = InputActionButton(page, "reset")
+    out_txt = OutputTextVerbatim(page, "txt")
+
+    out_txt.expect_value("2023-07-01 00:00:00")
+    btn_reset.loc.click()
+    out_txt.expect_value("2023-07-01 01:00:00")

shiny/ui/_input_update.py

@@ -776,7 +776,7 @@ def update_slider(
 
     # Get any non-None value to see if the `data-type` may need to change
     val = value[0] if isinstance(value, tuple) else value
-    present_val = next((x for x in [val, min, max]), None)
+    present_val = next((x for x in [val, min, max] if x is not None), None)
 
     data_type = None if present_val is None else _slider_type(present_val)
     if time_format is None and data_type and data_type[0:4] == "date":
@@ -785,10 +785,16 @@ def update_slider(
     min_num = None if min is None else _as_numeric(min)
     max_num = None if max is None else _as_numeric(max)
     step_num = None if step is None else _as_numeric(step)
+    if isinstance(value, tuple):
+        value_num = [_as_numeric(x) for x in value]
+    elif value is not None:
+        value_num = _as_numeric(value)
+    else:
+        value_num = None
 
     msg = {
         "label": label,
-        "value": value,
+        "value": value_num,
         "min": min_num,
         "max": max_num,
         "step": step_num,