Since 19.1: `CommonEngine` SSR App crashing in 19.1 when `UrlMatcher` is used

[denisyilmaz]

Command

serve

Is this a regression?

• Yes, this behavior used to work in the previous version

The previous version in which this bug was not present was

19.0

Description

Commit 6edb908 introduced a error message to indicate that UrlMatcher is not supported with SSR.
After further discussion in #29384 @alan-agius4 described that moving back to the CommonEngine might solve the issue, as only the AngularNodeAppEngine does not support the UrlMatcher in SSR Mode.

Minimal Reproduction

Unfortunately this is not resolving the issue. I created the following reproduction which shows that both applications (either with CommonEngine or AngularNodeAppEngine) are crashing as soon as a matcher function is used in the Router Config.

https://github.com/ynmstudio/bug-angular-19.1-commonengine-matcher-crash

CommonEngine

1. cd repro-app-commonengine
2. npm install
3. npm start

AngularNodeAppEngine

1. cd repro-app-appengine
2. npm install
3. npm start

Exception or Error

both applications fail with:

Error(s) occurred while extracting routes:
- The route '/' uses a route matcher which is not supported.
- The route '/' uses a route matcher which is not supported.

Your Environment

_                      _                 ____ _     ___
    / \   _ __   __ _ _   _| | __ _ _ __     / ___| |   |_ _|
   / △ \ | '_ \ / _` | | | | |/ _` | '__|   | |   | |    | |
  / ___ \| | | | (_| | |_| | | (_| | |      | |___| |___ | |
 /_/   \_\_| |_|\__, |\__,_|_|\__,_|_|       \____|_____|___|
                |___/
    

Angular CLI: 19.1.3
Node: 20.18.1
Package Manager: npm 10.8.2
OS: darwin arm64

Angular: 19.1.2
... animations, common, compiler, compiler-cli, core, forms
... platform-browser, platform-browser-dynamic, platform-server
... router

Package                         Version
---------------------------------------------------------
@angular-devkit/architect       0.1901.3
@angular-devkit/build-angular   19.1.3
@angular-devkit/core            19.1.3
@angular-devkit/schematics      19.1.3
@angular/cli                    19.1.3
@angular/ssr                    19.1.3
@schematics/angular             19.1.3
rxjs                            7.8.1
typescript                      5.7.3
zone.js                         0.15.0

Anything else relevant?

No response

[alan-agius4]

From the reproduction it seems that the issue is when using CommonEngine and having also prerendering enabled (https://github.com/ynmstudio/bug-angular-19.1-commonengine-matcher-crash/blob/0a4003ef1c1e914bdc485eed6a7a3df8e6801268/repro-app-commonengine/angular.json#L35), this causes the route extractor to be called and thus issue an error about the route matcher.

In this case, potentially we could omit the error.

[denisyilmaz]

@alan-agius4 i've added a repro-app-commonengine-without-prerender app to the reproduction. Even without the prerender option or with prerender: false the error is thrown.

[alan-agius4]

Spotted the issue and I have a fix in flight #29421