add clientside input/output callback test

Author: chadaeschliman

tests/integration/clientside/assets/clientside.js

@@ -81,5 +81,22 @@ window.dash_clientside.clientside = {
 
     states_list_to_str: function(val0, val1, st0, st1) {
         return JSON.stringify(dash_clientside.callback_context.states_list);
+    },
+
+    input_output_callback: function(inputValue) {
+        const triggered = dash_clientside.callback_context.triggered;
+        if (triggered.length==0){
+            return inputValue;
+        } else {
+            return inputValue + 1;
+        }
+    },
+
+    input_output_follower: function(inputValue) {
+        if (!window.callCount) {
+            window.callCount = 0
+        }
+        window.callCount += 1;
+        return inputValue.toString();
     }
 };

tests/integration/clientside/test_clientside.py

@@ -683,3 +683,37 @@ def test_clsd013_clientside_callback_context_states_list(dash_duo):
             '{"id":{"in1":2},"property":"value","value":"test 2"}]]'
         ),
     )
+
+
+def test_clsd014_input_output_callback(dash_duo):
+    app = Dash(__name__, assets_folder="assets")
+
+    app.layout = html.Div(
+        [html.Div(id="input-text"), dcc.Input(id="input", type="number", value=0)]
+    )
+
+    app.clientside_callback(
+        ClientsideFunction(
+            namespace="clientside", function_name="input_output_callback"
+        ),
+        Output("input", "value"),
+        Input("input", "value"),
+    )
+
+    app.clientside_callback(
+        ClientsideFunction(
+            namespace="clientside", function_name="input_output_follower"
+        ),
+        Output("input-text", "children"),
+        Input("input", "value"),
+    )
+
+    dash_duo.start_server(app)
+
+    dash_duo.find_element("#input").send_keys("2")
+    dash_duo.wait_for_text_to_equal("#input-text", "3")
+    call_count = dash_duo.driver.execute_script("return window.callCount;")
+
+    assert call_count == 2, "initial + changed once"
+
+    assert dash_duo.get_logs() == []