fix: DH-17076 LayoutHints on TreeTables were not being applied (#2041)

- Related to DH-17076
- Needed a Core patch:
deephaven/deephaven-core#5555
- Tested using both the Groovy snippet from the ticket
- Fixes #2035

Author: mofojed

packages/iris-grid/src/IrisGridTableModelTemplate.ts

@@ -177,6 +177,8 @@ class IrisGridTableModelTemplate<
 
   private _columnHeaderGroups: ColumnHeaderGroup[] = [];
 
+  private _isColumnHeaderGroupsInitialized = false;
+
   private _movedColumns: MoveOperation[] | null = null;
 
   /**
@@ -224,11 +226,6 @@ class IrisGridTableModelTemplate<
     // These rows can be sparse, so using a map instead of an array.
     this.pendingNewDataMap = new Map();
     this.pendingNewRowCount = 0;
-
-    this.columnHeaderGroups = IrisGridUtils.parseColumnHeaderGroups(
-      this,
-      this.layoutHints?.columnGroups ?? []
-    ).groups;
   }
 
   close(): void {
@@ -926,10 +923,12 @@ class IrisGridTableModelTemplate<
   }
 
   get columnHeaderGroupMap(): Map<string, ColumnHeaderGroup> {
+    this.initializeColumnHeaderGroups();
     return this._columnHeaderGroupMap;
   }
 
   get columnHeaderGroups(): ColumnHeaderGroup[] {
+    this.initializeColumnHeaderGroups();
     return this._columnHeaderGroups;
   }
 
@@ -952,6 +951,16 @@ class IrisGridTableModelTemplate<
     this.columnHeaderMaxDepth = maxDepth;
     this.columnHeaderParentMap = parentMap;
     this._columnHeaderGroupMap = groupMap;
+    this._isColumnHeaderGroupsInitialized = true;
+  }
+
+  private initializeColumnHeaderGroups(): void {
+    if (!this._isColumnHeaderGroupsInitialized) {
+      this.columnHeaderGroups = IrisGridUtils.parseColumnHeaderGroups(
+        this,
+        this.layoutHints?.columnGroups ?? []
+      ).groups;
+    }
   }
 
   row(y: ModelIndex): R | null {

packages/iris-grid/src/IrisGridTestUtils.ts

@@ -100,14 +100,16 @@ class IrisGridTestUtils {
     columns = this.makeColumns(),
     groupedColumns: DhType.Column[] = [],
     size = 1000000000,
-    sort = []
+    sort = [],
+    layoutHints?: Partial<DhType.LayoutHints>
   ): DhType.TreeTable {
     // eslint-disable-next-line @typescript-eslint/no-explicit-any
     const table = new (this.dh as any).TreeTable({
       columns,
       groupedColumns,
       size,
       sort,
+      layoutHints,
     });
     table.copy = jest.fn(() => Promise.resolve(table));
     return table;

packages/iris-grid/src/IrisGridTreeTableModel.test.ts

@@ -4,7 +4,7 @@ import IrisGridTreeTableModel from './IrisGridTreeTableModel';
 
 const irisGridTestUtils = new IrisGridTestUtils(dh);
 
-describe('IrisGridTreeTableModel', () => {
+describe('IrisGridTreeTableModel virtual columns', () => {
   const expectedVirtualColumn = expect.objectContaining({
     name: '__DH_UI_GROUP__',
     displayName: 'Group',
@@ -27,3 +27,48 @@ describe('IrisGridTreeTableModel', () => {
     }
   );
 });
+
+describe('IrisGridTreeTableModel layoutHints', () => {
+  test('null layout hints by default', () => {
+    const columns = irisGridTestUtils.makeColumns();
+    const table = irisGridTestUtils.makeTreeTable(columns, columns);
+    const model = new IrisGridTreeTableModel(dh, table);
+
+    expect(model.layoutHints).toEqual(null);
+  });
+
+  test('layoutHints set on tree table', () => {
+    const columns = irisGridTestUtils.makeColumns();
+    const layoutHints = { hiddenColumns: ['X'], frozenColumns: ['Y'] };
+    const table = irisGridTestUtils.makeTreeTable(
+      columns,
+      columns,
+      100,
+      [],
+      layoutHints
+    );
+    const model = new IrisGridTreeTableModel(dh, table);
+
+    expect(model.layoutHints).toEqual(layoutHints);
+  });
+
+  test('layoutHints undefined (e.g. not set on the table)', () => {
+    const columns = irisGridTestUtils.makeColumns();
+    const table = irisGridTestUtils.makeTreeTable(columns, columns, 100, []);
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    (table as any).layoutHints = undefined;
+    const model = new IrisGridTreeTableModel(dh, table);
+
+    expect(model.layoutHints).toEqual(undefined);
+  });
+
+  test('layoutHints property does not exist should not crash', () => {
+    const columns = irisGridTestUtils.makeColumns();
+    const table = irisGridTestUtils.makeTreeTable(columns, columns, 100, []);
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    delete (table as any).layoutHints;
+    const model = new IrisGridTreeTableModel(dh, table);
+
+    expect(model.layoutHints).toEqual(undefined);
+  });
+});

packages/iris-grid/src/IrisGridTreeTableModel.ts

@@ -21,6 +21,15 @@ export interface UITreeRow extends UIRow {
   hasChildren: boolean;
   depth: number;
 }
+
+type LayoutTreeTable = DhType.TreeTable & {
+  layoutHints?: null | DhType.LayoutHints;
+};
+
+function isLayoutTreeTable(table: DhType.TreeTable): table is LayoutTreeTable {
+  return (table as LayoutTreeTable).layoutHints !== undefined;
+}
+
 class IrisGridTreeTableModel extends IrisGridTableModelTemplate<
   DhType.TreeTable,
   UITreeRow
@@ -231,6 +240,13 @@ class IrisGridTreeTableModel extends IrisGridTableModelTemplate<
     return [this.virtualColumns.length, this.groupedColumns.length];
   }
 
+  get layoutHints(): DhType.LayoutHints | null | undefined {
+    if (isLayoutTreeTable(this.table)) {
+      return this.table.layoutHints;
+    }
+    return undefined;
+  }
+
   get hasExpandableRows(): boolean {
     return true;
   }