Add some basic test infrastructure

tests/test.py

@@ -0,0 +1,68 @@
+from streamlit.testing.v1 import AppTest
+
+from pathlib import Path
+
+import re
+
+app_file_path = Path(__file__).resolve().parent.parent / 'main.py'
+assert app_file_path.is_file()
+
+
+def test_custom_css():
+    at = AppTest.from_file(script_path=str(app_file_path), default_timeout=100.0).run()
+    css_container = at.main[0]
+    assert len(css_container) == 1
+    assert r'Targeting the tab button with a specific attribute and its inner <p> tag' in css_container.markdown[0].value
+
+
+def test_landing_page():
+    at = AppTest.from_file(script_path=str(app_file_path), default_timeout=100.0).run()
+
+    # The head container should only contain a title
+    cont_head = at.main[1]
+    assert len(cont_head) == 1
+    assert cont_head.title[0].body == 'Explore the Distribution Zoo'
+
+    # The body container should contain three cols
+    cont_body = at.main[2]
+    assert len(cont_body) == 1
+    assert len(cont_body.columns) == 3
+
+    # First col contains cont uni
+    current_col = cont_body.columns[0]
+    assert current_col.subheader[0].body == 'Continuous Univariate'
+    assert current_col.button[0].label == 'Normal'
+    assert current_col.button[1].label == 'Gamma'
+
+    # Second col contains disc uni
+    current_col = cont_body.columns[1]
+    assert current_col.subheader[0].body == 'Discrete Univariate'
+
+    # Third col contains multi
+    current_col = cont_body.columns[2]
+    assert current_col.subheader[0].body == 'Multivariate'
+
+    # The footer contains author and analytics
+    cont_foot = at.main[3]
+
+    author_subheader = cont_foot.subheader[0]
+    assert author_subheader.body == 'Authors:'
+    assert 'Ben Lambert' in cont_foot.markdown[0].value
+    assert 'Fergus Cooper' in cont_foot.markdown[0].value
+
+    analytics_subheader = cont_foot.subheader[1]
+    assert analytics_subheader.body == 'Analytics:'
+
+    match = re.search(r'Last month: used by (\d+) people over (\d+) sessions in (\d+) countries', cont_foot.markdown[1].value)
+    assert match is not None
+    people, sessions, countries = map(int, match.groups())
+    assert people > 0
+    assert sessions > 0
+    assert countries > 0
+
+    match = re.search(r'Since created: used by (\d+) people over (\d+) sessions in (\d+) countries', cont_foot.markdown[1].value)
+    assert match is not None
+    people, sessions, countries = map(int, match.groups())
+    assert people > 16123
+    assert sessions > 29586
+    assert countries > 132