Add hierarchical date row headers with expand/collapse

Author: mayagbarnes

README.md

@@ -275,7 +275,9 @@ Typed `date` and `datetime` fields are treated as hierarchy-capable dimensions w
 - Alternate grouping: `Week` is available from the header menu, but it is not part of the default drill path.
 - Explicit override precedence: explicit `date_grains[field]` beats interactive state, which beats the adaptive auto default.
 - Explicit opt-out: `date_grains[field] = None` preserves the raw/original date values for that field.
-- Hierarchical parent headers with +/- collapse/expand currently render on the **column axis**. Row-side temporal hierarchy parity is planned separately.
+- Hierarchical parent groups now render on **both axes**:
+  - on `columns`, parent headers such as `2024` or `Q1 2024` collapse/expand inline
+  - on `rows`, collapsing a parent replaces its visible descendants with one synthetic summary row
 
 ```python
 # Adaptive date hierarchy: grain chosen from the data's date range
@@ -326,7 +328,7 @@ Once a temporal field is active on an axis, open its header menu to:
 - switch directly to `Week`,
 - choose `Original` to persist a raw-date opt-out for that field.
 
-When a temporal field is on `columns`, parent headers such as `2024` or `Q1 2024` can be collapsed with the inline +/- toggle. This is a view-only collapse: the underlying leaf buckets remain the data/export contract.
+When a temporal field is on `columns`, parent headers such as `2024` or `Q1 2024` can be collapsed with the inline +/- toggle. When a temporal field is on `rows`, collapsing a parent replaces the visible child rows with one summary row for that parent. Both are view-only collapses: exports still emit the full expanded leaf-level table.
 
 Grouped buckets export as grouped labels such as `Jan 2024`, `Q1 2024`, or `2024-W03`; they are intentionally not exported as fake raw Excel dates.
 

e2e_playwright/e2e_utils.py

@@ -83,14 +83,13 @@
     "test_pivot_scalar_roundtrip",
 ]
 
+# Must match the exact order of st_pivot_table(key=...) calls in
+# pivot_table_interactions_app.py so get_pivot()'s nth() fallback matches
+# the right component when Streamlit does not emit a stable .st-key-* class.
 INTERACTIONS_PIVOT_KEYS = [
     "test_pivot",
     "test_pivot_subtotals",
     "test_pivot_cond_fmt",
-    "test_pivot_date_hierarchy",
-    "test_pivot_date_hierarchy_multidim",
-    "test_pivot_adaptive_year",
-    "test_pivot_adaptive_month",
     "test_pivot_locked",
     "test_pivot_locked_groups",
     "test_pivot_readonly",
@@ -101,6 +100,12 @@
     "test_pivot_per_measure_row_totals",
     "test_pivot_per_measure_col_totals",
     "test_pivot_col_groups",
+    "test_pivot_date_hierarchy",
+    "test_pivot_date_hierarchy_multidim",
+    "test_pivot_date_hierarchy_rows",
+    "test_pivot_date_hierarchy_rows_mixed",
+    "test_pivot_adaptive_year",
+    "test_pivot_adaptive_month",
     "test_pivot_drilldown_pagination",
     "test_pivot_drilldown_pagination_hybrid",
 ]

e2e_playwright/pivot_table_interactions_app.py

@@ -289,6 +289,30 @@ def render_app(data):
         on_config_change=noop,
     )
 
+    st.subheader("Date Hierarchy Rows Pivot")
+    st_pivot_table(
+        _make_date_hierarchy_data(),
+        key="test_pivot_date_hierarchy_rows",
+        rows=["order_date"],
+        columns=["region"],
+        values=["revenue"],
+        aggregation="sum",
+        interactive=True,
+        on_config_change=noop,
+    )
+
+    st.subheader("Date Hierarchy Mixed Rows Pivot")
+    st_pivot_table(
+        _make_date_hierarchy_data(),
+        key="test_pivot_date_hierarchy_rows_mixed",
+        rows=["region", "order_date"],
+        values=["revenue"],
+        aggregation="sum",
+        show_subtotals=["region"],
+        interactive=True,
+        on_config_change=noop,
+    )
+
     # Adaptive date grain: multi-year dataset -> auto-defaults to "year"
     st.subheader("Adaptive Grain (Multi-Year)")
     adaptive_year_df = pd.DataFrame(

e2e_playwright/pivot_table_interactions_test.py

@@ -457,6 +457,78 @@ def test_temporal_hierarchy_multidim_per_instance_collapse(page_at_app: Page):
     )
 
 
+def test_row_temporal_hierarchy_toggle_collapses_and_expands(page_at_app: Page):
+    """Row-side temporal parents collapse into a single synthetic summary row."""
+    page = page_at_app
+    container = (
+        page.locator(".st-key-test_pivot_date_hierarchy_rows")
+        .get_by_test_id("pivot-container")
+        .first
+    )
+    expect(container.get_by_test_id("pivot-table")).to_be_visible(timeout=15000)
+
+    expect(container.locator("thead").get_by_text("Quarter", exact=True)).to_be_visible(
+        timeout=5000
+    )
+    expect(container.get_by_text("Q1 2024")).to_be_visible(timeout=5000)
+    expect(container.get_by_text("Q4 2024")).to_be_visible(timeout=5000)
+
+    toggle_2024 = container.get_by_test_id("pivot-temporal-row-toggle-order_date-2024")
+    toggle_2024.click()
+
+    expect(container.get_by_text("Q1 2024")).to_be_hidden(timeout=5000)
+    expect(container.get_by_text("Q4 2024")).to_be_hidden(timeout=5000)
+    expect(container.get_by_test_id("pivot-temporal-parent-row")).to_be_visible(
+        timeout=5000
+    )
+    expect(
+        container.get_by_test_id("pivot-temporal-row-collapse-cell").first
+    ).to_be_visible(timeout=5000)
+
+    toggle_2024 = container.get_by_test_id("pivot-temporal-row-toggle-order_date-2024")
+    toggle_2024.click()
+    expect(container.get_by_text("Q1 2024")).to_be_visible(timeout=5000)
+    expect(container.get_by_text("Q4 2024")).to_be_visible(timeout=5000)
+
+
+def test_mixed_row_dimension_collapse_preserves_temporal_state(page_at_app: Page):
+    """Outer row-group collapse hides temporal parents and restores them on expand."""
+    page = page_at_app
+    container = (
+        page.locator(".st-key-test_pivot_date_hierarchy_rows_mixed")
+        .get_by_test_id("pivot-container")
+        .first
+    )
+    expect(container.get_by_test_id("pivot-table")).to_be_visible(timeout=15000)
+
+    us_2024_row = (
+        container.locator("tr").filter(has_text="US").filter(has_text="Q1 2024")
+    )
+    expect(us_2024_row).to_have_count(1, timeout=5000)
+    us_toggle = us_2024_row.locator(
+        '[data-testid="pivot-temporal-row-toggle-order_date-2024"]'
+    )
+    expect(us_toggle).to_be_visible(timeout=5000)
+    us_toggle.evaluate(
+        "el => { el.scrollIntoView({ block: 'center', inline: 'nearest' }); el.click(); }"
+    )
+    expect(container.get_by_text("Q1 2024")).to_have_count(1, timeout=10000)
+    expect(container.get_by_test_id("pivot-temporal-parent-row")).to_have_count(
+        1, timeout=10000
+    )
+
+    container.get_by_test_id("pivot-group-toggle-US").click()
+    expect(container.get_by_text("US Total")).to_be_visible(timeout=5000)
+    expect(container.get_by_test_id("pivot-temporal-parent-row")).to_have_count(
+        0, timeout=5000
+    )
+
+    container.get_by_test_id("pivot-group-toggle-US").click()
+    expect(container.get_by_test_id("pivot-temporal-parent-row")).to_have_count(
+        1, timeout=10000
+    )
+
+
 def test_drilldown_opens_on_cell_click(page_at_app: Page):
     """Clicking a data cell opens the drilldown panel with a detail table."""
     page = page_at_app
@@ -973,12 +1045,13 @@ def test_hierarchical_sort_preserves_parent_groups(page_at_app: Page):
     expect(region_headers.first).to_be_visible(timeout=5000)
     regions_before = [h.inner_text() for h in region_headers.all()]
 
-    container.get_by_test_id("header-menu-trigger-Category").click()
-    menu = container.get_by_test_id("header-menu-Category")
-    expect(menu).to_be_visible(timeout=5000)
-
-    menu.get_by_test_id("header-sort-key-asc").click()
-    page.wait_for_timeout(1500)
+    activate_sort_option(
+        page,
+        container.get_by_test_id("header-menu-trigger-Category"),
+        "header-menu-Category",
+        "header-sort-key-asc",
+    )
+    page.wait_for_timeout(500)
 
     regions_after = [h.inner_text() for h in region_headers.all()]
     assert regions_before == regions_after, (
@@ -1049,13 +1122,23 @@ def test_child_toggle_disabled_when_parent_collapsed(page_at_app: Page):
 
 
 def _open_drilldown_with_pagination(page: Page, pivot_key: str):
-    """Click the first data cell (Alpha × 2023 → 700 records) and wait for pagination."""
+    """Click the Alpha × 2023 data cell (700 raw rows) and wait for pagination."""
     container = get_pivot(page, pivot_key)
     expect(container.get_by_test_id("pivot-table")).to_be_visible(timeout=15000)
-    container.get_by_test_id("pivot-data-cell").first.evaluate("el => el.click()")
+    # Pin the cell by row label so DOM/column order quirks (e.g. WebKit) cannot
+    # hit a different bucket than the 700-row Alpha/2023 intersection.
+    alpha_row = container.get_by_test_id("pivot-data-row").filter(has_text="Alpha")
+    expect(alpha_row).to_have_count(1, timeout=10000)
+    cell = alpha_row.get_by_test_id("pivot-data-cell").first
+    cell.scroll_into_view_if_needed()
+    expect(cell).to_be_visible(timeout=5000)
+    cell.evaluate("el => el.click()")
     panel = page.get_by_test_id("drilldown-panel")
     expect(panel).to_be_visible(timeout=10000)
-    expect(page.get_by_test_id("drilldown-pagination")).to_be_visible(timeout=10000)
+    expect(panel).to_contain_text("700", timeout=15000)
+    pagination = page.get_by_test_id("drilldown-pagination")
+    pagination.scroll_into_view_if_needed()
+    expect(pagination).to_be_visible(timeout=10000)
     return container, panel
 
 
@@ -1135,6 +1218,8 @@ def test_adaptive_grain_multi_year_defaults_to_year(page_at_app: Page):
         .first
     )
     expect(container.get_by_test_id("pivot-table")).to_be_visible(timeout=15000)
+    # Year is the auto grain but hierarchy metadata is skipped for grain === "year",
+    # so the corner header still uses the combined dimension label.
     header = container.locator("th").filter(has_text="order_date (Year)")
     expect(header).to_be_visible(timeout=10000)
 
@@ -1148,5 +1233,7 @@ def test_adaptive_grain_3month_defaults_to_month(page_at_app: Page):
         .first
     )
     expect(container.get_by_test_id("pivot-table")).to_be_visible(timeout=15000)
-    header = container.locator("th").filter(has_text="order_date (Month)")
-    expect(header).to_be_visible(timeout=10000)
+    # Month grain uses hierarchy [year, quarter, month] on row headers.
+    expect(container.get_by_test_id("pivot-row-dim-label-order-date-2")).to_have_text(
+        "Month", timeout=10000
+    )

streamlit_app.py

@@ -1471,16 +1471,17 @@
 available as an alternate grouping. Period-over-period display modes
 (previous-period, previous-year) are unlocked automatically.
 
-For this release, the Excel/Power BI-style parent header collapse/expand UI is
-available on the **column axis**. Exports still keep the full leaf-level date
-columns even when a parent date header is collapsed in the view.
+The Excel/Power BI-style parent collapse/expand UI now works on **both axes**.
+On columns, parent headers collapse into summary columns. On rows, collapsing a
+parent replaces its visible descendants with one synthetic summary row. Exports
+still keep the full leaf-level date structure regardless of collapse state.
 
 **Try it:**
 - In the first table, notice the adaptive default grain based on the data range.
 - Open the `order_date` header menu to drill up/down, switch to Week, or choose Original.
-- Use the +/- toggle on a parent date header to collapse a year/quarter group on the column axis.
+- Use the +/- toggle on a parent date group to collapse or expand it on either axis.
 - Open the `Revenue` value header menu to switch between raw values and period comparisons.
-- Compare the other tables for explicit override, global opt-out, and per-field opt-out.
+- Compare the other tables for explicit override, global opt-out, per-field opt-out, and the row-side collapse example in the bottom-right.
 
 **API parameters used:** `auto_date_hierarchy`, `date_grains`, `show_values_as`
 """
@@ -1553,7 +1554,7 @@
         auto_date_hierarchy=False,
     )
 
-date_col_5, _ = st.columns(2)
+date_col_5, date_col_6 = st.columns(2)
 
 with date_col_5:
     st.caption("Per-field Original opt-out")
@@ -1568,6 +1569,20 @@
         date_grains={"ship_date": None},
     )
 
+with date_col_6:
+    st.caption(
+        "Row-side hierarchy with collapsible parent rows (click the +/- in the row headers)"
+    )
+    st_pivot_table(
+        df_dates,
+        key="date_hierarchy_rows",
+        rows=["order_date"],
+        columns=["region"],
+        values=["Revenue"],
+        aggregation="sum",
+        show_totals=True,
+    )
+
 with st.expander("View Code"):
     st.code(
         """
@@ -1615,6 +1630,14 @@
     values=["Revenue"],
     date_grains={"ship_date": None},
 )
+
+st_pivot_table(
+    df_dates,
+    key="date_hierarchy_rows",
+    rows=["order_date"],
+    columns=["region"],
+    values=["Revenue"],
+)
 """,
         language="python",
     )