Editor: view-scoped data context — per-view dataset columns in hints and transforms

src/app/services/active-dataset.test.ts

@@ -0,0 +1,113 @@
+import { beforeEach, describe, expect, test } from 'vitest';
+import { createDataset } from '@core/dataset';
+import { useDatasetStore } from '../stores/DatasetStore';
+import { dataInfoAt } from './active-dataset';
+
+/** Seed a library dataset, profiled from inline rows. */
+function seed(name: string, rows: Record<string, unknown>[]): void {
+  useDatasetStore
+    .getState()
+    .add(createDataset({ name, data: rows, format: 'json', source: 'inline' }));
+}
+
+/** An offset inside the first occurrence of `marker` in `text`. */
+function at(text: string, marker: string): number {
+  return text.indexOf(marker) + 1;
+}
+
+const names = (cols: ReadonlyArray<{ name: string }>) => cols.map((c) => c.name).sort();
+
+beforeEach(() => {
+  useDatasetStore.getState().reset();
+});
+
+describe('dataInfoAt — view-scoped data context', () => {
+  test('resolves a library binding case-insensitively', () => {
+    seed('Sales', [{ region: 'W', revenue: 10 }]);
+    const text = '{ "data": { "name": "sales" }, "encoding": { "x": { "field": "MK" } } }';
+    const info = dataInfoAt(text, at(text, 'MK'));
+    expect(info.name).toBe('Sales');
+    expect(names(info.columnTypes)).toEqual(['region', 'revenue']);
+  });
+
+  test('each layer sees its own dataset, not a sibling view’s', () => {
+    seed('Sales', [{ region: 'W', revenue: 10 }]);
+    seed('Regions', [{ region: 'W', population: 100 }]);
+    const text = JSON.stringify(
+      {
+        layer: [
+          { data: { name: 'Sales' }, encoding: { x: { field: 'sales_mk' } } },
+          { data: { name: 'Regions' }, encoding: { y: { field: 'regions_mk' } } },
+        ],
+      },
+      null,
+      2,
+    );
+    const inLayer0 = dataInfoAt(text, at(text, 'sales_mk'));
+    const inLayer1 = dataInfoAt(text, at(text, 'regions_mk'));
+    expect(inLayer0.name).toBe('Sales');
+    expect(names(inLayer0.columnTypes)).toEqual(['region', 'revenue']);
+    expect(inLayer1.name).toBe('Regions');
+    expect(names(inLayer1.columnTypes)).toEqual(['population', 'region']);
+  });
+
+  test('a child without its own data inherits the parent binding', () => {
+    seed('Sales', [{ region: 'W', revenue: 10 }]);
+    const text = JSON.stringify(
+      { data: { name: 'Sales' }, layer: [{ encoding: { x: { field: 'mk' } } }] },
+      null,
+      2,
+    );
+    const info = dataInfoAt(text, at(text, '"mk"'));
+    expect(info.name).toBe('Sales');
+    expect(names(info.columnTypes)).toEqual(['region', 'revenue']);
+  });
+
+  test('profiles an inline binding (ghost dataset, no name)', () => {
+    const text =
+      '{ "data": { "values": [{ "a": 1, "b": 2 }] }, "encoding": { "x": { "field": "MK" } } }';
+    const info = dataInfoAt(text, at(text, 'MK'));
+    expect(info.name).toBeNull();
+    expect(names(info.columnTypes)).toEqual(['a', 'b']);
+  });
+
+  test('profiles a self-defined top-level datasets binding', () => {
+    const text = JSON.stringify(
+      {
+        datasets: { local: [{ c: 1, d: 2 }] },
+        data: { name: 'local' },
+        encoding: { x: { field: 'mk' } },
+      },
+      null,
+      2,
+    );
+    const info = dataInfoAt(text, at(text, '"mk"'));
+    expect(info.name).toBeNull();
+    expect(names(info.columnTypes)).toEqual(['c', 'd']);
+  });
+
+  test('offers ancestor-derived fields, not a sibling view’s', () => {
+    seed('Sales', [{ region: 'W', revenue: 10 }]);
+    const text = JSON.stringify(
+      {
+        data: { name: 'Sales' },
+        transform: [{ calculate: 'datum.revenue * 2', as: 'shared' }],
+        layer: [
+          { transform: [{ calculate: 'x', as: 'inner' }], encoding: { x: { field: 'mk0' } } },
+          { transform: [{ calculate: 'y', as: 'sibling' }], encoding: { y: { field: 'mk1' } } },
+        ],
+      },
+      null,
+      2,
+    );
+    const fields = dataInfoAt(text, at(text, 'mk0')).fields.map((f) => f.name);
+    expect(fields).toContain('shared'); // top-level (inherited)
+    expect(fields).toContain('inner'); // this view
+    expect(fields).not.toContain('sibling'); // the other layer
+  });
+
+  test('a url/generator binding yields no static columns', () => {
+    const url = '{ "data": { "url": "x.csv" }, "encoding": { "x": { "field": "MK" } } }';
+    expect(dataInfoAt(url, at(url, 'MK')).columnTypes).toEqual([]);
+  });
+});