fix(#3426): build-time warning for unresolvable flow templates + guard the formula re-read

.changeset/flow-template-lint-and-hydrate-guards.md

@@ -0,0 +1,32 @@
+---
+"@objectstack/lint": patch
+"@objectstack/cli": patch
+"@objectstack/trigger-record-change": patch
+---
+
+fix(#3426): build-time warning for unresolvable flow template paths + guard the formula re-read
+
+Two follow-ups to #3426 (the formula/lookup `{record.<path>}` template gap that #3445 began closing).
+
+**Build-time signal (the issue's fallback ask).** `os validate` now flags a
+record-change flow node whose `{record.<path>}` template cannot resolve —
+turning the previous SILENT blank into an advisory warning. Two cases, via the
+new `@objectstack/lint` rule `validateFlowTemplatePaths`:
+
+- `flow-template-unknown-field` — `{record.<x>}` where `<x>` is neither a
+  declared field nor a system column (a typo like `{record.full_naem}`).
+- `flow-template-lookup-traversal` — `{record.<lookup>.<field>}`, a cross-object
+  hop the seeded record carries only as a scalar id (still unsupported; tracked
+  on #3426).
+
+Deliberately quiet: formula fields, bare lookup ids, numeric indexes into
+`multiple` lookups (#1872), `json` sub-paths, and system columns are NOT flagged,
+and flows bound to an object this stack does not define are skipped (no schema to
+compare against).
+
+**Hydration re-read guards.** The `trigger-record-change` computed-field re-read
+(#3445) is now (a) skipped when the object declares no `formula` field — the only
+thing it adds — via the engine's optional `getObjectConfig`, and (b) memoized per
+write on the shared HookContext, so N flows on one written record share ONE
+re-read instead of N. Any uncertainty falls back to the prior unconditional
+re-read (correctness over the optimization).

packages/cli/src/commands/validate.ts

@@ -19,6 +19,7 @@ import { validateCapabilityReferences } from '@objectstack/lint';
 import { validateVisibilityPredicates } from '@objectstack/lint';
 import { validateSecurityPosture } from '@objectstack/lint';
 import { validateFlowTriggerReadiness } from '@objectstack/lint';
+import { validateFlowTemplatePaths } from '@objectstack/lint';
 import { validateReadonlyFlowWrites } from '@objectstack/lint';
 import { preflightRequiredCapabilities, renderCapabilityMessage } from '../utils/capability-preflight.js';
 import {
@@ -428,6 +429,22 @@ export default class Validate extends Command {
         }
       }
 
+      // 3g-bis. Flow template path references (#3426): a `{record.<path>}` token
+      //     in a node template that names an unknown field, or hops through a
+      //     lookup relation the seeded record carries only as a scalar id, both
+      //     render a SILENT empty string at runtime. Advisory: the head object
+      //     may come from another package (skipped there), and the runtime still
+      //     produces output (a blank), so nothing is fully broken.
+      if (!flags.json) printStep('Checking flow template references...');
+      const flowTemplateFindings = validateFlowTemplatePaths(normalized as Record<string, unknown>);
+      const flowTemplateWarnings = flowTemplateFindings.filter((f) => f.severity === 'warning');
+      if (!flags.json) {
+        for (const w of flowTemplateWarnings.slice(0, 50)) {
+          console.log(chalk.yellow(`  ⚠ ${w.where}: ${w.message}`));
+          console.log(chalk.dim(`      ${w.hint}`));
+        }
+      }
+
       // 3e2. [#3425] Readonly flow-write guardrail. A `runAs:user` update_record
       //      that writes a static-`readonly` field is a SILENT no-op — the engine
       //      strips it from the UPDATE payload (#2948) yet the step reports
@@ -545,7 +562,7 @@ export default class Validate extends Command {
           valid: true,
           manifest: config.manifest,
           stats,
-          warnings: [...exprWarnings, ...widgetWarnings, ...actionRefWarnings, ...styleWarnings, ...jsxWarnings, ...capWarnings, ...flowReadinessWarnings, ...securityAdvisories, ...capProviderWarnings],
+          warnings: [...exprWarnings, ...widgetWarnings, ...actionRefWarnings, ...styleWarnings, ...jsxWarnings, ...capWarnings, ...flowReadinessWarnings, ...flowTemplateWarnings, ...securityAdvisories, ...capProviderWarnings],
           conversions: conversionNotices,
           specVersionGap: specGap,
           duration: timer.elapsed(),

packages/lint/src/index.ts

@@ -39,6 +39,16 @@ export type {
   FlowTriggerReadinessSeverity,
 } from './validate-flow-trigger-readiness.js';
 
+export {
+  validateFlowTemplatePaths,
+  FLOW_TEMPLATE_UNKNOWN_FIELD,
+  FLOW_TEMPLATE_LOOKUP_TRAVERSAL,
+} from './validate-flow-template-paths.js';
+export type {
+  FlowTemplatePathFinding,
+  FlowTemplatePathSeverity,
+} from './validate-flow-template-paths.js';
+
 export {
   validateReadonlyFlowWrites,
   FLOW_UPDATE_READONLY_FIELD,

packages/lint/src/validate-flow-template-paths.test.ts

@@ -0,0 +1,192 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+import { describe, it, expect } from 'vitest';
+import {
+  validateFlowTemplatePaths,
+  FLOW_TEMPLATE_UNKNOWN_FIELD,
+  FLOW_TEMPLATE_LOOKUP_TRAVERSAL,
+} from './validate-flow-template-paths.js';
+
+type AnyRec = Record<string, unknown>;
+
+/** A crm_lead object with a scalar, a formula, a lookup, and a multi-lookup. */
+const LEAD_OBJECT: AnyRec = {
+  name: 'crm_lead',
+  fields: {
+    first_name: { name: 'first_name', type: 'text' },
+    last_name: { name: 'last_name', type: 'text' },
+    company: { name: 'company', type: 'text' },
+    full_name: { name: 'full_name', type: 'formula' },
+    crm_account: { name: 'crm_account', type: 'lookup', reference_to: 'crm_account' },
+    target_channels: { name: 'target_channels', type: 'lookup', reference_to: 'channel', multiple: true },
+    payload: { name: 'payload', type: 'json' },
+  },
+};
+
+/** Build a record-change flow with one notify node carrying the given templates. */
+function flowWith(notify: AnyRec, objectName = 'crm_lead'): AnyRec {
+  return {
+    objects: [LEAD_OBJECT],
+    flows: [
+      {
+        name: 'notify_lead',
+        type: 'record_change',
+        nodes: [
+          { id: 'start', type: 'start', config: { objectName, triggerType: 'record-created' } },
+          { id: 'n1', type: 'notify', notify },
+        ],
+      },
+    ],
+  };
+}
+
+describe('validateFlowTemplatePaths', () => {
+  it('flags an unknown field in a {record.<x>} template (typo)', () => {
+    const findings = validateFlowTemplatePaths(
+      flowWith({ title: 'New lead: {record.full_naem}', body: 'x' }),
+    );
+    expect(findings).toHaveLength(1);
+    expect(findings[0].rule).toBe(FLOW_TEMPLATE_UNKNOWN_FIELD);
+    expect(findings[0].severity).toBe('warning');
+    expect(findings[0].message).toContain('full_naem');
+  });
+
+  it('flags a lookup cross-object hop {record.<lookup>.<field>}', () => {
+    const findings = validateFlowTemplatePaths(
+      flowWith({ title: 'From {record.crm_account.name}', body: 'x' }),
+    );
+    expect(findings).toHaveLength(1);
+    expect(findings[0].rule).toBe(FLOW_TEMPLATE_LOOKUP_TRAVERSAL);
+    expect(findings[0].message).toContain('crm_account.name');
+  });
+
+  it('does NOT flag a formula field (valid, hydrated since #3445)', () => {
+    const findings = validateFlowTemplatePaths(
+      flowWith({ title: 'New lead: {record.full_name}', body: '{record.company}' }),
+    );
+    expect(findings).toHaveLength(0);
+  });
+
+  it('does NOT flag a plain scalar field', () => {
+    const findings = validateFlowTemplatePaths(
+      flowWith({ title: '{record.first_name} {record.last_name}', body: '{record.company}' }),
+    );
+    expect(findings).toHaveLength(0);
+  });
+
+  it('does NOT flag a bare lookup id (no sub-path)', () => {
+    const findings = validateFlowTemplatePaths(
+      flowWith({ title: 'acct {record.crm_account}', body: 'x' }),
+    );
+    expect(findings).toHaveLength(0);
+  });
+
+  it('does NOT flag a numeric index into a multiple lookup (#1872)', () => {
+    const findings = validateFlowTemplatePaths(
+      flowWith({ title: 'ch {record.target_channels.0}', body: 'x' }),
+    );
+    expect(findings).toHaveLength(0);
+  });
+
+  it('does NOT flag a sub-path into a json field', () => {
+    const findings = validateFlowTemplatePaths(
+      flowWith({ title: '{record.payload.foo}', body: 'x' }),
+    );
+    expect(findings).toHaveLength(0);
+  });
+
+  it('does NOT flag system/audit columns', () => {
+    const findings = validateFlowTemplatePaths(
+      flowWith({ title: '{record.id} {record.created_at} {record.owner}', body: 'x' }),
+    );
+    expect(findings).toHaveLength(0);
+  });
+
+  it('ignores non-record tokens (flow vars, NOW(), $User)', () => {
+    const findings = validateFlowTemplatePaths(
+      flowWith({ title: '{some_var.field} {NOW()} {$User.Email}', body: 'x' }),
+    );
+    expect(findings).toHaveLength(0);
+  });
+
+  it('skips a flow whose object is not defined in this stack', () => {
+    const findings = validateFlowTemplatePaths({
+      objects: [LEAD_OBJECT],
+      flows: [
+        {
+          name: 'external',
+          type: 'record_change',
+          nodes: [
+            { id: 'start', type: 'start', config: { objectName: 'sys_user', triggerType: 'record-created' } },
+            { id: 'n1', type: 'notify', notify: { title: '{record.anything.deep}', body: 'x' } },
+          ],
+        },
+      ],
+    });
+    expect(findings).toHaveLength(0);
+  });
+
+  it('skips non-record-triggered flows', () => {
+    const findings = validateFlowTemplatePaths({
+      objects: [LEAD_OBJECT],
+      flows: [
+        {
+          name: 'manual',
+          type: 'screen',
+          nodes: [
+            { id: 'start', type: 'start', config: {} },
+            { id: 'n1', type: 'notify', notify: { title: '{record.full_naem}', body: 'x' } },
+          ],
+        },
+      ],
+    });
+    expect(findings).toHaveLength(0);
+  });
+
+  it('dedupes a repeated bad reference to one finding per node', () => {
+    const findings = validateFlowTemplatePaths(
+      flowWith({ title: '{record.full_naem}', body: 'again {record.full_naem}' }),
+    );
+    expect(findings).toHaveLength(1);
+  });
+
+  it('resolves objectName from the typed start block too', () => {
+    const findings = validateFlowTemplatePaths({
+      objects: [LEAD_OBJECT],
+      flows: [
+        {
+          name: 'typed_start',
+          type: 'record_change',
+          nodes: [
+            { id: 'start', type: 'start', start: { objectName: 'crm_lead', triggerType: 'record-created' } },
+            { id: 'n1', type: 'notify', notify: { title: '{record.crm_account.name}', body: 'x' } },
+          ],
+        },
+      ],
+    });
+    expect(findings).toHaveLength(1);
+    expect(findings[0].rule).toBe(FLOW_TEMPLATE_LOOKUP_TRAVERSAL);
+  });
+
+  it('detects references in freeform config and other node types (http url)', () => {
+    const findings = validateFlowTemplatePaths({
+      objects: [LEAD_OBJECT],
+      flows: [
+        {
+          name: 'webhook',
+          type: 'record_change',
+          nodes: [
+            { id: 'start', type: 'start', config: { objectName: 'crm_lead', triggerType: 'record-created' } },
+            { id: 'h1', type: 'http', http: { url: 'https://x.test/{record.full_naem}', method: 'GET' } },
+          ],
+        },
+      ],
+    });
+    expect(findings).toHaveLength(1);
+    expect(findings[0].rule).toBe(FLOW_TEMPLATE_UNKNOWN_FIELD);
+  });
+
+  it('returns empty when there are no flows', () => {
+    expect(validateFlowTemplatePaths({ objects: [LEAD_OBJECT] })).toHaveLength(0);
+  });
+});