test(frontend/history): column-filter regression suites (refs #166)

Adds two test files exercising the new History column-filter wiring:

* history-column-filters.test.ts — Purchase History table:
  numeric expr, categorical set, stacked AND, invalid expr (no-op),
  clear, and the term-as-stringified-categorical case.

* approval-queue-column-filters.test.ts — Approval Queue table:
  numeric expr (monthly_cost >= N), categorical set (payment in
  {…}), stacked AND across provider+created_by, invalid expr (no-op),
  the NaN-as-missing contract for null monthly_cost (so "= 0" and
  "> 0" don't coincidentally match unreported rows), and clear.

Both suites mock the heavy module transitive deps (api / navigation /
utils / state / confirmDialog / approval-details / toast / skeleton /
recommendations) so the pure column-filter helpers can be exercised
without standing up a DOM.

Author: cristim

frontend/src/__tests__/approval-queue-column-filters.test.ts

@@ -0,0 +1,125 @@
+/**
+ * Approval Queue column-filter regression suite (issue #166).
+ *
+ * Covers the inline per-column filters wired onto the Approval Queue
+ * table headers. Filterable columns: Provider, Account, Service, Term,
+ * Payment, Created by (categorical), Count, Monthly Cost, Upfront Cost,
+ * Monthly Savings (numeric). Status is excluded by design — the queue
+ * scope is already pending|notified.
+ *
+ * Tested matrix:
+ *   1. Numeric expr filter narrows by predicate (monthly_cost >= N).
+ *   2. Categorical set filter narrows by membership (payment in set).
+ *   3. Multiple filters AND together across columns.
+ *   4. Invalid numeric expression is skipped (no exception, no narrowing).
+ *   5. NaN-as-missing contract: monthly_cost == null produces NaN, which
+ *      fails every numeric predicate (not coincidentally matches "= 0").
+ *   6. Clearing returns a fresh clone of the input.
+ */
+
+import { applyApprovalQueueColumnFilters } from '../history';
+import type { HistoryPurchase } from '../types';
+import type { ApprovalQueueColumnFilters } from '../state';
+
+jest.mock('../api', () => ({}));
+jest.mock('../navigation', () => ({ switchTab: jest.fn() }));
+jest.mock('../utils', () => ({
+  formatCurrency: jest.fn((v) => `$${v ?? 0}`),
+  formatDate: jest.fn((v) => v),
+  formatTerm: jest.fn((y) => `${y} Year${y === 1 ? '' : 's'}`),
+  escapeHtml: jest.fn((s) => s ?? ''),
+}));
+jest.mock('../state', () => ({
+  subscribeProvider: jest.fn().mockReturnValue(() => {}),
+  subscribeAccount: jest.fn().mockReturnValue(() => {}),
+}));
+jest.mock('../confirmDialog', () => ({ confirmDialog: jest.fn() }));
+jest.mock('../approval-details', () => ({ buildApprovalDetailsBody: jest.fn() }));
+jest.mock('../toast', () => ({ showToast: jest.fn() }));
+jest.mock('../lib/skeleton', () => ({ showSkeletonRows: jest.fn(), teardownSkeleton: jest.fn() }));
+jest.mock('../recommendations', () => ({ getAccountName: jest.fn((id: string) => id) }));
+
+function mkRow(overrides: Partial<HistoryPurchase>): HistoryPurchase {
+  return {
+    purchase_id: 'p',
+    timestamp: '2024-01-01T00:00:00Z',
+    provider: 'aws',
+    service: 'ec2',
+    resource_type: 'reserved-instance',
+    region: 'us-east-1',
+    count: 1,
+    term: 1,
+    payment: 'all_upfront',
+    upfront_cost: 100,
+    monthly_cost: 50,
+    estimated_savings: 30,
+    account_id: 'acct-1',
+    created_by_user_email: 'alice@example.com',
+    status: 'pending',
+    ...overrides,
+  };
+}
+
+const rows: HistoryPurchase[] = [
+  mkRow({ purchase_id: 'a', provider: 'aws',   account_id: 'acct-1', payment: 'all_upfront',     monthly_cost: 50,   estimated_savings: 30,  created_by_user_email: 'alice@example.com' }),
+  mkRow({ purchase_id: 'b', provider: 'aws',   account_id: 'acct-2', payment: 'no_upfront',      monthly_cost: 200,  estimated_savings: 100, created_by_user_email: 'bob@example.com' }),
+  mkRow({ purchase_id: 'c', provider: 'azure', account_id: 'acct-2', payment: 'partial_upfront', monthly_cost: null as unknown as number | undefined, estimated_savings: 60, created_by_user_email: 'alice@example.com' }),
+  mkRow({ purchase_id: 'd', provider: 'gcp',   account_id: 'acct-3', payment: 'all_upfront',     monthly_cost: 500,  estimated_savings: 250, created_by_user_email: 'carol@example.com' }),
+];
+
+describe('applyApprovalQueueColumnFilters', () => {
+  test('numeric expr: monthly_cost >= 200 narrows to expensive rows', () => {
+    const filters: ApprovalQueueColumnFilters = {
+      monthly_cost: { kind: 'expr', expr: '>=200' },
+    };
+    const out = applyApprovalQueueColumnFilters(rows, filters);
+    expect(out.map((r) => r.purchase_id)).toEqual(['b', 'd']);
+  });
+
+  test('categorical set: payment in {all_upfront} narrows to those rows', () => {
+    const filters: ApprovalQueueColumnFilters = {
+      payment: { kind: 'set', values: ['all_upfront'] },
+    };
+    const out = applyApprovalQueueColumnFilters(rows, filters);
+    expect(out.map((r) => r.purchase_id)).toEqual(['a', 'd']);
+  });
+
+  test('multiple filters AND together (provider=aws + created_by=alice)', () => {
+    const filters: ApprovalQueueColumnFilters = {
+      provider: { kind: 'set', values: ['aws'] },
+      created_by: { kind: 'set', values: ['alice@example.com'] },
+    };
+    const out = applyApprovalQueueColumnFilters(rows, filters);
+    expect(out.map((r) => r.purchase_id)).toEqual(['a']);
+  });
+
+  test('invalid numeric expression is skipped (filter is a no-op)', () => {
+    const filters: ApprovalQueueColumnFilters = {
+      savings: { kind: 'expr', expr: 'not-a-num' },
+    };
+    const out = applyApprovalQueueColumnFilters(rows, filters);
+    expect(out).toHaveLength(rows.length);
+  });
+
+  test('null monthly_cost fails every numeric predicate (NaN contract)', () => {
+    // Row c has monthly_cost: null. A "= 0" predicate must NOT match it,
+    // and a ">0" predicate must NOT match it either.
+    const eqZero: ApprovalQueueColumnFilters = {
+      monthly_cost: { kind: 'expr', expr: '0' },
+    };
+    expect(applyApprovalQueueColumnFilters(rows, eqZero).map((r) => r.purchase_id))
+      .not.toContain('c');
+
+    const gtZero: ApprovalQueueColumnFilters = {
+      monthly_cost: { kind: 'expr', expr: '>0' },
+    };
+    expect(applyApprovalQueueColumnFilters(rows, gtZero).map((r) => r.purchase_id))
+      .not.toContain('c');
+  });
+
+  test('clearing filters via empty record returns a fresh clone', () => {
+    const out = applyApprovalQueueColumnFilters(rows, {});
+    expect(out).toEqual(rows);
+    expect(out).not.toBe(rows);
+  });
+});

frontend/src/__tests__/history-column-filters.test.ts

@@ -0,0 +1,117 @@
+/**
+ * Purchase History column-filter regression suite (issue #166).
+ *
+ * Covers the inline per-column filters wired onto the Purchase History
+ * table headers. The existing Status chip-row remains the canonical
+ * filter for status — these tests exercise the new column-filter slice
+ * (provider/service/type/region/term + count/upfront_cost/savings).
+ *
+ * Tested matrix:
+ *   1. Numeric expr filter narrows by predicate (savings > N).
+ *   2. Categorical set filter narrows by membership (provider in set).
+ *   3. Multiple filters AND together across columns.
+ *   4. Invalid numeric expression is skipped (no exception, no narrowing).
+ *   5. Clearing a filter via setPurchaseHistoryColumnFilter(col, null)
+ *      restores the full slice.
+ *   6. Term column treats absent vs zero correctly — categorical-empty
+ *      filtering.
+ */
+
+import { applyPurchaseHistoryColumnFilters } from '../history';
+import type { HistoryPurchase } from '../types';
+import type { PurchaseHistoryColumnFilters } from '../state';
+
+// history.ts pulls in api/state/navigation transitively; the column-filter
+// helper is pure (operates on the passed-in rows + filter record), but the
+// module import path still resolves those — stub them out so the test runs
+// without an apiBase / DOM context.
+jest.mock('../api', () => ({}));
+jest.mock('../navigation', () => ({ switchTab: jest.fn() }));
+jest.mock('../utils', () => ({
+  formatCurrency: jest.fn((v) => `$${v ?? 0}`),
+  formatDate: jest.fn((v) => v),
+  formatTerm: jest.fn((y) => `${y} Year${y === 1 ? '' : 's'}`),
+  escapeHtml: jest.fn((s) => s ?? ''),
+}));
+jest.mock('../state', () => ({
+  subscribeProvider: jest.fn().mockReturnValue(() => {}),
+  subscribeAccount: jest.fn().mockReturnValue(() => {}),
+}));
+jest.mock('../confirmDialog', () => ({ confirmDialog: jest.fn() }));
+jest.mock('../approval-details', () => ({ buildApprovalDetailsBody: jest.fn() }));
+jest.mock('../toast', () => ({ showToast: jest.fn() }));
+jest.mock('../lib/skeleton', () => ({ showSkeletonRows: jest.fn(), teardownSkeleton: jest.fn() }));
+jest.mock('../recommendations', () => ({ getAccountName: jest.fn((id: string) => id) }));
+
+function mkRow(overrides: Partial<HistoryPurchase>): HistoryPurchase {
+  return {
+    purchase_id: 'p',
+    timestamp: '2024-01-01T00:00:00Z',
+    provider: 'aws',
+    service: 'ec2',
+    resource_type: 'reserved-instance',
+    region: 'us-east-1',
+    count: 1,
+    term: 1,
+    upfront_cost: 100,
+    estimated_savings: 50,
+    ...overrides,
+  };
+}
+
+const rows: HistoryPurchase[] = [
+  mkRow({ purchase_id: 'a', provider: 'aws',   service: 'ec2',  region: 'us-east-1', count: 1, term: 1, upfront_cost: 100,  estimated_savings: 50 }),
+  mkRow({ purchase_id: 'b', provider: 'aws',   service: 'rds',  region: 'us-west-2', count: 3, term: 3, upfront_cost: 500,  estimated_savings: 200 }),
+  mkRow({ purchase_id: 'c', provider: 'azure', service: 'ec2',  region: 'eu-west-1', count: 5, term: 1, upfront_cost: 1000, estimated_savings: 400 }),
+  mkRow({ purchase_id: 'd', provider: 'gcp',   service: 'ec2',  region: 'us-east-1', count: 2, term: 1, upfront_cost: 250,  estimated_savings: 80  }),
+];
+
+describe('applyPurchaseHistoryColumnFilters', () => {
+  test('numeric expr: savings > 100 narrows to high-saving rows', () => {
+    const filters: PurchaseHistoryColumnFilters = {
+      savings: { kind: 'expr', expr: '>100' },
+    };
+    const out = applyPurchaseHistoryColumnFilters(rows, filters);
+    expect(out.map((r) => r.purchase_id)).toEqual(['b', 'c']);
+  });
+
+  test('categorical set: provider in {aws, gcp} excludes azure', () => {
+    const filters: PurchaseHistoryColumnFilters = {
+      provider: { kind: 'set', values: ['aws', 'gcp'] },
+    };
+    const out = applyPurchaseHistoryColumnFilters(rows, filters);
+    expect(out.map((r) => r.purchase_id)).toEqual(['a', 'b', 'd']);
+  });
+
+  test('multiple filters AND together (provider=aws + savings >= 100)', () => {
+    const filters: PurchaseHistoryColumnFilters = {
+      provider: { kind: 'set', values: ['aws'] },
+      savings: { kind: 'expr', expr: '>=100' },
+    };
+    const out = applyPurchaseHistoryColumnFilters(rows, filters);
+    expect(out.map((r) => r.purchase_id)).toEqual(['b']);
+  });
+
+  test('invalid numeric expression is skipped (filter is a no-op)', () => {
+    const filters: PurchaseHistoryColumnFilters = {
+      savings: { kind: 'expr', expr: '>>nope' },
+    };
+    const out = applyPurchaseHistoryColumnFilters(rows, filters);
+    // Parse failure → filter ignored; full slice passes.
+    expect(out).toHaveLength(rows.length);
+  });
+
+  test('clearing filters via empty record returns a fresh clone', () => {
+    const out = applyPurchaseHistoryColumnFilters(rows, {});
+    expect(out).toEqual(rows);
+    expect(out).not.toBe(rows);
+  });
+
+  test('term filter uses categorical-set semantics with stringified values', () => {
+    const filters: PurchaseHistoryColumnFilters = {
+      term: { kind: 'set', values: ['3'] },
+    };
+    const out = applyPurchaseHistoryColumnFilters(rows, filters);
+    expect(out.map((r) => r.purchase_id)).toEqual(['b']);
+  });
+});