fix: Address datepicker issues

shiny/ui/_input_date.py

@@ -45,7 +45,7 @@ def input_date(
     value
         The starting date. Either a :class:`~datetime.date` object, or a string in
         `yyyy-mm-dd` format. If None (the default), will use the current date in the
-        client's time zone.
+        client's time zone. If an empty string is passed, the date picker will be blank.
     min
         The minimum allowed date. Either a :class:`~datetime.date` object, or a string in
         yyyy-mm-dd format.
@@ -310,6 +310,9 @@ def _date_input_tag(
 def _as_date_attr(x: Optional[date | str]) -> Optional[str]:
     if x is None:
         return None
-    if isinstance(x, date):
-        return str(x)
-    return str(date.fromisoformat(x))
+    if isinstance(x, str):
+        if len(x) == 0:
+            return x
+        x = date.fromisoformat(x)
+    # Using strftime here to ensure we just just a date, regardless of if H:M:S are included
+    return x.strftime("%Y-%m-%d")

shiny/ui/_input_update.py

@@ -464,7 +464,6 @@ def update_date(
         An input label.
     value
         The starting date. Either a `date()` object, or a string in yyyy-mm-dd format.
-        If ``None`` (the default), will use the current date in the client's time zone.
     min
         The minimum allowed value.
     max
@@ -475,14 +474,15 @@ def update_date(
 
     Note
     ----
-    {note}
+    You cannot update the value of a date input to `None` or an empty string.
 
     See Also
     --------
     * :func:`~shiny.ui.input_date`
     """
 
     session = require_active_session(session)
+
     msg = {
         "label": session._process_ui(label) if label is not None else None,
         "value": _as_date_attr(value),

tests/playwright/shiny/components/datepicker/app.py

@@ -0,0 +1,93 @@
+from datetime import date
+
+from dateutil.relativedelta import relativedelta
+
+from shiny import App, Inputs, Outputs, Session, reactive, render, ui
+
+min_date = date.fromisoformat("2011-11-04")
+max_date = min_date + relativedelta(days=10)
+
+# Our input requires strings to be in the format "YYYY-MM-DD"
+str_min = min_date.strftime("%Y-%m-%d")
+str_max = max_date.strftime("%Y-%m-%d")
+
+app_ui = ui.page_fluid(
+    ui.input_date(
+        "start_date_picker",
+        "Date Type Input:",
+        value=max_date,
+        min=min_date,
+        max=max_date,
+        format="dd.mm.yyyy",
+        language="en",
+    ),
+    ui.output_text("start"),
+    ui.input_date(
+        "min_date_picker",
+        "Date Type Input:",
+        value=min_date,
+        min=min_date,
+        max=max_date,
+        format="dd.mm.yyyy",
+        language="en",
+    ),
+    ui.output_text("min"),
+    ui.input_date(
+        "str_date_picker",
+        "String Type Input:",
+        value="2023-10-01",
+        min="2000-01-01",
+        max="2023-10-01",
+        format="dd-mm-yyyy",
+        language="en",
+    ),
+    ui.output_text("str_format"),
+    ui.input_date("none_date_picker", "None Type Input:"),
+    ui.output_text("none_format"),
+    ui.input_date(
+        "empty_date_picker",
+        "empty Type Input:",
+        value="",
+        min=None,
+        max=None,
+        format="dd-mm-yyyy",
+        language="en",
+    ),
+    ui.output_text("empty_format"),
+    ui.input_action_button("update", "Update Dates"),
+)
+
+
+def server(input: Inputs, output: Outputs, session: Session):
+    @render.text
+    def start():
+        return "Date Picker Value: " + str(input.start_date_picker())
+
+    @render.text
+    def min():
+        return "Date Picker Value: " + str(input.min_date_picker())
+
+    @render.text
+    def str_format():
+        return "Date Picker Value: " + str(input.str_date_picker())
+
+    @render.text
+    def none_format():
+        return "Date Picker Value: " + str(input.none_date_picker())
+
+    @render.text
+    def empty_format():
+        return "Date Picker Value: " + str(input.empty_date_picker())
+
+    @reactive.effect
+    @reactive.event(input.update, ignore_none=True, ignore_init=True)
+    def _():
+        d = date.fromisoformat("2011-11-05")
+        ui.update_date("start_date_picker", value=d)
+        ui.update_date("str_date_picker", value="2020-01-01")
+
+    # Note: You cannot update the value of a date input to None (it will be dropped).
+    # Note: You cannot update the value of a date input to an empty string. This is a Bootstrap Datepicker limitation.
+
+
+app = App(app_ui, server, debug=True)

tests/playwright/shiny/components/datepicker/test_datepicker.py

@@ -0,0 +1,59 @@
+import datetime
+
+from playwright.sync_api import Page
+
+from shiny.playwright import controller
+from shiny.run import ShinyAppProc
+
+
+def test_dynamic_navs(page: Page, local_app: ShinyAppProc) -> None:
+    page.goto(local_app.url)
+
+    # Check the initial state of the date picker where value = max
+    date1 = controller.InputDate(page, "start_date_picker")
+    date1.expect_value("14.11.2011")
+
+    # Can't find a way to inspect the actual display date in the datepicker,
+    # as even in the broken example, the correct attribute was still set.
+    # To work around this, we will check the displayed value to ensure the
+    # correct value is being passed to the server.
+    date_output = controller.OutputText(page, "start")
+    date_output.expect_value("Date Picker Value: 2011-11-14")
+
+    # Test the date picker with the min date = initial value (unchanged case)
+    date2 = controller.InputDate(page, "min_date_picker")
+    date2.expect_value("04.11.2011")
+
+    date_output2 = controller.OutputText(page, "min")
+    date_output2.expect_value("Date Picker Value: 2011-11-04")
+
+    # Test the date picker with the date set as a string instead of as a date object
+    date3 = controller.InputDate(page, "str_date_picker")
+    date3.expect_value("01-10-2023")
+
+    date_output3 = controller.OutputText(page, "str_format")
+    date_output3.expect_value("Date Picker Value: 2023-10-01")
+
+    # Test the date picker with a None value inputted
+    # None defaults to today's date
+    input = datetime.date.today().strftime("%Y-%m-%d")
+    date4 = controller.InputDate(page, "none_date_picker")
+    date4.expect_value(input)
+
+    date_output4 = controller.OutputText(page, "none_format")
+    date_output4.expect_value("Date Picker Value: " + input)
+
+    # Test the default value when an empty string is passed is correctly blank
+    date5 = controller.InputDate(page, "empty_date_picker")
+    date5.expect_value("")
+
+    date_output5 = controller.OutputText(page, "empty_format")
+    date_output5.expect_value("Date Picker Value: None")
+
+    controller.InputActionButton(page, "update").click()
+
+    date1.expect_value("05.11.2011")
+    date_output.expect_value("Date Picker Value: 2011-11-05")
+
+    date3.expect_value("01-01-2020")
+    date_output3.expect_value("Date Picker Value: 2020-01-01")