angular/packages/router
Andrew Scott 0960592d3d fix(router): pass outlet context to split to fix empty path named outlets
The `split` helper function in `packages/router/src/utils/config_matching.ts` was blind to the current outlet being processed. When encountering an empty path named outlet in the config, it would assume it needed to pull it in as a synthetic empty group, even if we were already in the process of resolving that very outlet!

When navigating to `/(secondary:component-copy)` with this config:

```typescript
{
  path: '',
  component: MainLayout,
  children: [
    { path: '', outlet: 'secondary', component: SecondaryComponent, children: [{path: 'component-copy'}] }
  ]
}
```

The router uses `MainLayout` as a pass-through and calls `split` on its children with segments `['component-copy']`.
`split` uses the `containsEmptyPathMatchesWithNamedOutlets` helper to determine if there are any candidate empty path named outlets to pull in. Because of this, it sees `{ path: '', outlet: 'secondary' }` and says: "Ah, an empty path named outlet! I must pull it in!"
Rather than falling through to standard segment matching, it returns `UrlSegmentGroup(segments: [], children: {secondary: emptyGroup})`.
The router then tries to process `primary` (with `[]` segments) and fails because the config only has `secondary`. It also tries to process `secondary` with the `emptyGroup`. While `{ path: '', outlet: 'secondary' }` matches the empty group, its child `{ path: 'component-copy' }` fails to match because the `emptyGroup` has no segments! So both branches fail, resulting in a `NoMatch` error for the entire navigation!

Pulling in empty path named outlets IS desired when they act as siblings to segments we are matching. This has worked before and continues to work!

```typescript
{
  path: 'a',
  children: [
    { path: 'b', component: ComponentB },
    { path: '', component: ComponentC, outlet: 'aux' }
  ]
}
```

When navigating to `a/b`, `split` sees segments `['b']` and the `aux` empty path. It pulls in `aux` so it gets instantiated alongside `b`. This is correct!

If we have a named outlet with a non-empty path under an empty path parent:

```typescript
{
  path: '',
  component: MainLayout,
  children: [
    { path: 'component-copy', outlet: 'secondary', component: ComponentE }
  ]
}
```

When we navigate to `/(secondary:component-copy)`:
- `split` uses `containsEmptyPathMatchesWithNamedOutlets` to see if there are any empty path named outlets. Since it only sees `path: 'component-copy'`, it returns `false`.
- It falls through to standard segment matching, which finds `component-copy` in the segments array and activates it flawlessly!

This worked perfectly before the fix because it didn't use `containsEmptyPathMatchesWithNamedOutlets`.

The fix passes the **current active outlet context** into `split`. If `split` finds an empty path named outlet that matches the outlet we are already processing, it ignores it as a pull-in candidate.

When evaluating `MainLayout` children for `secondary`:
- URL Segments left to process: `['component-copy']`
- Current Outlet: `secondary`
- `childConfig`: `[{ path: '', outlet: 'secondary' }]`

Previously, `split` saw the empty path and pulled it in as a synthetic empty group, breaking matching. Now, since `getOutlet(r) === outlet` (both are `secondary`), the fix ignores it. Instead of returning empty segments, it **falls through to standard segment matching**, which successfully find the `component-copy` segment!

When evaluating `ComponentA` children for `primary`:
- URL Segments left to process: `['b']`
- Current Outlet: `primary`
- `childConfig`: `[{ path: 'b' }, { path: '', outlet: 'aux' }]`

Since `getOutlet(aux) !== primary`, the fix **does not ignore it**. `split` pulls in `aux: emptyGroup` as a sibling, instantiating `ComponentC` alongside `ComponentB`. This preserves correct behavior for auxiliary outlets!

fixes #67708

(cherry picked from commit daa9b2a9d6)
2026-04-01 11:48:47 +02:00
..
docs feat(router): add controls for route cleanup 2026-01-05 14:43:56 -05:00
scripts refactor: move angular source to /packages rather than modules/@angular 2017-03-08 16:29:27 -08:00
src fix(router): pass outlet context to split to fix empty path named outlets 2026-04-01 11:48:47 +02:00
test fix(router): pass outlet context to split to fix empty path named outlets 2026-04-01 11:48:47 +02:00
testing refactor: prepare for required changeDetection prop on G3. 2026-03-20 15:52:42 -07:00
upgrade build: format md files 2025-11-06 10:03:05 -08:00
.gitignore refactor: move angular source to /packages rather than modules/@angular 2017-03-08 16:29:27 -08:00
BUILD.bazel build: Add dom-navigation types to router (#64905) 2025-11-06 17:42:04 +00:00
index.ts refactor: update license text to point to angular.dev (#57901) 2024-09-24 15:33:00 +02:00
package.json refactor(router): Build out integration with browser Navigation API (#64905) 2025-11-06 17:42:04 +00:00
PACKAGE.md build: format md files 2025-11-06 10:03:05 -08:00
public_api.ts refactor: update license text to point to angular.dev (#57901) 2024-09-24 15:33:00 +02:00
README.md build: format md files 2025-11-06 10:03:05 -08:00
tsconfig.json build: Add dom-navigation types to router (#64905) 2025-11-06 17:42:04 +00:00

Angular Router

Managing state transitions is one of the hardest parts of building applications. This is especially true on the web, where you also need to ensure that the state is reflected in the URL. In addition, we often want to split applications into multiple bundles and load them on demand. Doing this transparently isnt trivial.

The Angular router is designed to solve these problems. Using the router, you can declaratively specify application state, manage state transitions while taking care of the URL, and load components on demand.

Guide

Read the dev guide here.