feat(eslint-rules): add prefer-direct-reexport eslint rule

[Victor Genaev (mainframev)]

Adds a new workspace ESLint rule @nx/workspace-prefer-direct-reexport.

It flags exported bindings that are just an alias of something imported from another module, and points at the direct export … from form instead:

// flagged
import { renderToolbar_unstable } from '@fluentui/react-toolbar';
export const renderToolbar = renderToolbar_unstable;

// preferred
export { renderToolbar_unstable as renderToolbar } from '@fluentui/react-toolbar';

What detects

Aliasing an import through a local binding

// ❌ reported
import { renderBase } from 'pkg';
export const render = renderBase;

// ✅ preferred
export { renderBase as render } from 'pkg';

** Default import re-exported under a name**

// ❌ reported
import renderBase from 'pkg';
export const render = renderBase;

// ✅ preferred
export { default as render } from 'pkg';

Named import re-exported as default

// ❌ reported
import { renderBase } from 'pkg';
export default renderBase;

// ✅ preferred
export { renderBase as default } from 'pkg';

Namespace import re-exported under a name

// ❌ reported
import * as local from 'pkg';
export { local as publicName };

// ✅ preferred
export * as publicName from 'pkg';

Alias chains through intermediate bindings

// ❌ reported
import { renderBase } from 'pkg';
const localRender = renderBase;
export const render = localRender;

// ✅ preferred
export { renderBase as render } from 'pkg';

Identity function wrappers

// ❌ reported — forwards its arguments unchanged
import { renderBase } from 'pkg';
export const render = props => renderBase(props);

// ❌ reported
export function render(props, options) {
  return renderBase(props, options);
}

// ✅ preferred
export { renderBase as render } from 'pkg';

Type-only aliases

// ❌ reported
import type { BaseProps } from 'pkg';
export type Props = BaseProps;

// ✅ preferred
export type { BaseProps as Props } from 'pkg';

What it leaves alone

Anything that changes the public shape, is reassignable, or has no export … from equivalent:

// the annotation narrows the public signature — not an identity re-export
export const render = (value: unknown) => renderBase(value);

//  the type annotation is the public contract
type PublicSignature = typeof renderBase;
export const render: PublicSignature = renderBase;

// reassignable, so it is not a re-export
export let render = renderBase;

// wrapping changes runtime behaviour
export const render = async props => renderBase(props);
export function* render(props) {
  return renderBase(props);
}

// composed or instantiated types are new types
export type Props = BaseProps & OtherProps;
export type Props = BaseProps<any>;
export type Props<T> = BaseProps;
export interface Props extends BaseProps {}

// a member of a namespace, not the namespace itself
import * as upstream from 'pkg';
export const render = upstream.renderBase;

// no `export … from` form exists for a namespace as default
import * as local from 'pkg';
export default local;

Perf check

Measured on CI in a fork with two PRs differing only by this rule (baseline vs with rule). Full workspace lint, 247 projects, Nx cache disabled, ubuntu-latest, 3 runs each.

	Duration
Without rule	1148s
With rule	1149s
Delta	+1s (+0.09%)

Per-rule cost from ESLint's own profiler (TIMING=100) on react-components/react-button/library:

Rule	Time
@typescript-eslint/no-deprecated	570.837 ms
@nx/workspace-base-hook-no-forbidden-runtime	25.372 ms
@nx/workspace-prefer-direct-reexport	0.396 ms

[github-actions]

📊 Bundle size report

✅ No changes found

[github-actions]

Pull request demo site: URL

[Martin Hochel (Hotell)]

great addition to our harness, left some comments. ty

[Martin Hochel (Hotell)]

left some comments, nothing blocking