App testing cheat sheet

Text elements

from streamlit.testing.v1 import AppTest at = AppTest.from_file("cheatsheet_app.py") # Headers assert "My app" in at.title[0].value assert "New topic" in at.header[0].value assert "Interesting sub-topic" in at.subheader[0].value assert len(at.divider) == 2 # Body / code assert "Hello, world!" in at.markdown[0].value assert "import streamlit as st" in at.code[0].value assert "A cool diagram" in at.caption[0].value assert "Hello again, world!" in at.text[0].value assert "\int a x^2 \,dx" in at.latex[0].value

Input widgets

from streamlit.testing.v1 import AppTest at = AppTest.from_file("cheatsheet_app.py") # button assert at.button[0].value == False at.button[0].click().run() assert at.button[0].value == True # checkbox assert at.checkbox[0].value == False at.checkbox[0].check().run() # uncheck() is also supported assert at.checkbox[0].value == True # color_picker assert at.color_picker[0].value == "#FFFFFF" at.color_picker[0].pick("#000000").run() # date_input assert at.date_input[0].value == datetime.date(2019, 7, 6) at.date_input[0].set_value(datetime.date(2022, 12, 21)).run() # form_submit_button - shows up just like a button assert at.button[0].value == False at.button[0].click().run() assert at.button[0].value == True # multiselect assert at.multiselect[0].value == ["foo", "bar"] at.multiselect[0].select("baz").unselect("foo").run() # number_input assert at.number_input[0].value == 5 at.number_input[0].increment().run() # radio assert at.radio[0].value == "Bar" assert at.radio[0].index == 3 at.radio[0].set_value("Foo").run() # selectbox assert at.selectbox[0].value == "Bar" assert at.selectbox[0].index == 3 at.selectbox[0].set_value("Foo").run() # select_slider assert at.select_slider[0].value == "Feb" at.select_slider[0].set_value("Mar").run() at.select_slider[0].set_range("Apr", "Jun").run() # slider assert at.slider[0].value == 2 at.slider[0].set_value(3).run() at.slider[0].set_range(4, 6).run() # text_area assert at.text_area[0].value == "Hello, world!" at.text_area[0].set_value("Hello, yourself!").run() # text_input assert at.text_input[0].value == "Hello, world!") at.text_input[0].set_value("Hello, yourself!").run() # time_input assert at.time_input[0].value == datetime.time(8, 45) at.time_input[0].set_value(datetime.time(12, 30)) # toggle assert at.toggle[0].value == False assert at.toggle[0].label == "Debug mode" at.toggle[0].set_value(True).run() assert at.toggle[0].value == True

Data elements

from streamlit.testing.v1 import AppTest at = AppTest.from_file("cheatsheet_app.py") # dataframe expected_df = pd.DataFrame([1, 2, 3]) assert at.dataframe[0].value.equals(expected_df) # metric assert at.metric[0].value == "9500" assert at.metric[0].delta == "1000" # json assert at.json[0].value == '["hi", {"foo": "bar"}]' # table table_df = pd.DataFrame([1, 2, 3]) assert at.table[0].value.equals(table_df)

Layouts and containers

from streamlit.testing.v1 import AppTest at = AppTest.from_file("cheatsheet_app.py") # sidebar at.sidebar.text_input[0].set_value("Jane Doe") # columns at.columns[1].markdown[0].value == "Hello, world!" # tabs at.tabs[2].markdown[0].value == "Hello, yourself!"

Chat elements

from streamlit.testing.v1 import AppTest at = AppTest.from_file("cheatsheet_app.py") # chat_input at.chat_input[0].set_value("Do you know any jokes?").run() # Note: chat_input value clears after every re-run (like in a real app) # chat_message assert at.chat_message[0].markdown[0].value == "Do you know any jokes?" assert at.chat_message[0].avatar == "user"

Status elements

from streamlit.testing.v1 import AppTest at = AppTest.from_file("cheatsheet_app.py") # exception assert len(at.exception) == 1 assert "TypeError" in at.exception[0].value # Other in-line alerts: success, info, warning, error assert at.success[0].value == "Great job!" assert at.info[0].value == "Please enter an API key to continue" assert at.warning[0].value == "Sorry, the passwords didn't match" assert at.error[0].value == "Something went wrong :(" # toast assert at.toast[0].value == "That was lit!" and at.toast[0].icon == "🔥"

Limitations

As of Streamlit 1.28, the following Streamlit features are not natively supported by AppTest. However, workarounds are possible for many of them by inspecting the underlying proto directly using AppTest.get(). We plan to regularly add support for missing elements until all features are supported.

• Chart elements (st.bar_chart, st.line_chart, etc)
• Media elements (st.image, st.video, st.audio)
• st.file_uploader
• st.data_editor
• st.expander
• st.status
• st.camera_input
• st.download_button
• st.link_button

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