Chart builder: filter/calculate transforms, data preview, and inline expression validation

src/app/stores/ChartBuilderStore.test.ts

@@ -140,6 +140,95 @@ describe('applyWarningFix', () => {
   });
 });
 
+describe('filters (1C)', () => {
+  test('addFilter seeds a predicate on the first column with its derived type', () => {
+    const id = seedDataset('S', [{ region: 'N', revenue: 5 }]);
+    cb().init(id);
+    cb().addFilter();
+    const f = cb().config.filters?.[0];
+    expect(f).toMatchObject({
+      mode: 'predicate',
+      field: 'region',
+      fieldType: 'nominal',
+      op: 'equal',
+    });
+  });
+
+  test('setFilterField re-derives the field type and clamps an out-of-range operator', () => {
+    const id = seedDataset('S', [{ region: 'N', revenue: 5 }]);
+    cb().init(id);
+    cb().addFilter();
+    const fid = cb().config.filters![0].id;
+    // Point at the measure, choose an ordering op, then point back at the category:
+    cb().setFilterField(fid, 'revenue');
+    cb().updateFilter(fid, { op: 'gt', value: '3' });
+    expect(cb().config.filters![0]).toMatchObject({ fieldType: 'quantitative', op: 'gt' });
+    cb().setFilterField(fid, 'region'); // gt is invalid on a category → resets to equal
+    expect(cb().config.filters![0]).toMatchObject({
+      field: 'region',
+      fieldType: 'nominal',
+      op: 'equal',
+    });
+  });
+
+  test('removeFilter drops the row', () => {
+    const id = seedDataset('S', [{ region: 'N' }]);
+    cb().init(id);
+    cb().addFilter();
+    cb().addFilter();
+    const first = cb().config.filters![0].id;
+    cb().removeFilter(first);
+    expect(cb().config.filters).toHaveLength(1);
+    expect(cb().config.filters![0].id).not.toBe(first);
+  });
+
+  test('setFilterMode toggles to expression and back, seeding a field on return', () => {
+    const id = seedDataset('S', [{ region: 'N', revenue: 5 }]);
+    cb().init(id);
+    cb().addFilter();
+    const fid = cb().config.filters![0].id;
+    cb().setFilterMode(fid, 'expression');
+    expect(cb().config.filters![0].mode).toBe('expression');
+    cb().setFilterMode(fid, 'predicate');
+    expect(cb().config.filters![0]).toMatchObject({ mode: 'predicate', field: 'region' });
+  });
+});
+
+describe('calculated fields (1C)', () => {
+  test('a calculated field becomes selectable on a channel, defaulting to quantitative', () => {
+    const id = seedDataset('S', [{ a: 1, b: 2 }]);
+    cb().init(id);
+    cb().addCalculate();
+    const cid = cb().config.calculates![0].id;
+    cb().updateCalculate(cid, { as: 'total', expr: 'datum.a + datum.b' });
+    cb().setChannelColumn('y', 'total');
+    expect(cb().config.encodings.y).toEqual({ field: 'total', type: 'quantitative' });
+  });
+
+  test('removing a calculated field clears any channel that referenced it', () => {
+    const id = seedDataset('S', [{ a: 1, b: 2 }]);
+    cb().init(id);
+    cb().addCalculate();
+    const cid = cb().config.calculates![0].id;
+    cb().updateCalculate(cid, { as: 'total', expr: 'datum.a + datum.b' });
+    cb().setChannelColumn('y', 'total');
+    cb().removeCalculate(cid);
+    expect(cb().config.calculates).toHaveLength(0);
+    expect(cb().config.encodings.y).toBeNull(); // pruned — its field no longer exists
+  });
+
+  test('renaming a referenced calculated field prunes the now-dangling channel', () => {
+    const id = seedDataset('S', [{ a: 1 }]);
+    cb().init(id);
+    cb().addCalculate();
+    const cid = cb().config.calculates![0].id;
+    cb().updateCalculate(cid, { as: 'doubled', expr: 'datum.a * 2' });
+    cb().setChannelColumn('x', 'doubled');
+    cb().updateCalculate(cid, { as: 'tripled' }); // the channel still points at "doubled"
+    expect(cb().config.encodings.x).toBeNull();
+  });
+});
+
 describe('createSnippet', () => {
   test('builds a linked snippet, activates it, and resets the builder', () => {
     const id = seedDataset('Sales', [