test(command,wasm): column width, row-header width and column group labels follow displays (improvise-cq1q.12)

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VdfEGXA7aJ6ftMsCc9PJze

context/code/core.md

@@ -1796,6 +1796,13 @@ messages and the view title say (improvise-cq1q.13). A display change alone does
 not move `layout_fingerprint`, so it resets no cursor; no production path changes
 one yet.
 
+`AxisFrame::cat_displays` is projected and validated, but nothing paints it yet
+(the corner label has no consumer); that is a gap to close when one does, not a
+bug. The new wire fields carry no `serde(default)`, so a payload from before this
+change is refused: deliberate, since zero is a claim and not an absence (the same
+reason as `AxisFrame::first`), and bundles are stamped so a client and host
+cannot differ.
+
 **`.improv` neither writes nor reads a display in this step.** A saved file still
 carries keys only, so a display set in memory is lost on save; display persists
 only with the new version literal (improvise-cq1q.5).

context/test-evidence/core.md

@@ -2122,3 +2122,24 @@ From Copilot's finding on #336: `item_displays` is a parallel list on a wire typ
 that derives `Deserialize`. The control parses a well-formed axis first; then a
 shorter list and an absent one beside `items: Some(..)` are each refused with the
 "item displays" message. Without the `try_from` the same JSON parses.
+
+### ui::viewport::tests::a_column_is_as_wide_as_the_display_its_header_draws
+
+From the Opus review of #336: `header_level_seed` could measure keys and the
+suite stayed green. The fixture's column display ("Januaryyyyy", 11) is far longer
+than its key ("Jan") and the cell, so the 5-column minimum cannot hide it. Rival:
+the seed reads `tuple` instead of `display`; the width is 5, not 12, and this test
+fails.
+
+### ui::viewport::tests::the_row_header_is_as_wide_as_the_display_its_rows_draw
+
+Rival: `compute_row_header_width` reads `tuple`. That width drives `visible_cols`
+on the keypress path (the improvise-gtn7.1 shape: a scroll measured elsewhere than
+it is drawn), so a key measurement lets the cursor scroll to an undrawn column.
+The display "Eastern Seaboard" against the key "E" gives 17, not the 4 minimum.
+
+### render::tests::a_column_group_header_is_painted_by_its_display
+
+Rival: `col_groups` labels a run with `g.name`. The browser test for group displays
+covered row groups only; this one folds a column frame whose group "Q1" is shown as
+"First quarter" and fails on the key.

crates/improvise-command/src/ui/viewport.rs

@@ -253,6 +253,51 @@ mod tests {
     use crate::view::Axis;
     use crate::workbook::Workbook;
 
+    /// One row and one column, each item shown under a display far longer than its
+    /// key and than the cell, so the 5-column minimum cannot hide a key measurement.
+    fn long_displays() -> Workbook {
+        let mut wb = Workbook::new("T");
+        wb.add_category("Type").unwrap();
+        wb.add_category("Month").unwrap();
+        wb.add_item("Type", "E").unwrap();
+        wb.add_item("Month", "Jan").unwrap();
+        wb.model.set_cell(
+            CellKey::new(vec![
+                ("Type".into(), "E".into()),
+                ("Month".into(), "Jan".into()),
+            ]),
+            CellValue::Number(1.0),
+        );
+        wb.model
+            .category_mut("Type")
+            .unwrap()
+            .set_item_display("E", "Eastern Seaboard");
+        wb.model
+            .category_mut("Month")
+            .unwrap()
+            .set_item_display("Jan", "Januaryyyyy");
+        wb
+    }
+
+    #[test]
+    fn a_column_is_as_wide_as_the_display_its_header_draws() {
+        let wb = long_displays();
+        let layout = GridLayout::new(&wb.model, wb.active_view());
+        let plan = FormatPlan::of(&wb.model, wb.active_view());
+        let widths = compute_col_widths(&wb.model, &layout, &plan);
+        assert_eq!(widths, vec!["Januaryyyyy".len() as u16 + 1]);
+    }
+
+    #[test]
+    fn the_row_header_is_as_wide_as_the_display_its_rows_draw() {
+        let wb = long_displays();
+        let layout = GridLayout::new(&wb.model, wb.active_view());
+        assert_eq!(
+            compute_row_header_width(&layout),
+            "Eastern Seaboard".len() as u16 + 1
+        );
+    }
+
     /// Q1 = {Jan, Feb} collapsed, Q2 = {Apr}; F0 = Revenue and F(i) = F(i-1) twice.
     fn folded_chain() -> Workbook {
         let mut wb = Workbook::new("T");

crates/improvise-wasm-client/src/render.rs

@@ -959,6 +959,33 @@ mod tests {
         assert_eq!(model.categories[1].label, "Eastern Seaboard");
     }
 
+    #[test]
+    fn a_column_group_header_is_painted_by_its_display() {
+        use improvise_protocol::{AxisFrame, FrameGroup};
+        let mut client = init();
+        let state = client.state_mut();
+        state.fold(&Command::Project(Projection::Grid(GridUpdate::ColFrame(
+            AxisFrame {
+                cats: vec!["Month".into()],
+                cat_displays: vec!["Period".into()],
+                first: 0,
+                entries: vec![
+                    FrameEntry::Group(FrameGroup {
+                        level: 0,
+                        depth: 0,
+                        name: "Q1".into(),
+                        display: "First quarter".into(),
+                        collapsed: false,
+                    }),
+                    item("Jan"),
+                ],
+            },
+        ))));
+        let groups = client.model().col_groups;
+        assert_eq!(groups.len(), 1);
+        assert_eq!(groups[0].label.as_deref(), Some("First quarter"));
+    }
+
     fn client_with_panels() -> Client {
         let mut client = init();
         client