I have tested it on Mac and Windows. On Mac works well.
On Windows, when it was updating to 2.3.1-rc.0 (from 2.3-beta.1), it got hung up or frozen, but this error has been common on Windows systems and I’ve got it before with other versions of Meteor (when create the first meteor app or update the Meteor version). So, I wouldn’t consider it as a new issue, just need to kill the process and run it again to solve it.
Once meteor app was updated, I ran it and I got this error:
"C:\Program Files\nodejs\node.exe" C:\Users\Steeltwins\AppData\Roaming\npm\node_modules\yarn\bin\yarn.js test
yarn run v1.22.10
$ meteor test --settings ./settings/settings-development.json --once --full-app --driver-package meteortesting:mocha
[[[[[ Tests ]]]]]
=> Started proxy.
=> [HMR] Dev server listening on port 3003.
=> Started MongoDB.
Browserslist: caniuse-lite is outdated. Please run next command `npm update`
W20210705-15:38:00.577(-5)? (STDERR) C:\Users\Steeltwins\AppData\Local\.meteor\packages\meteor-tool\2.3.1-rc.0\mt-os.windows.x86_64\dev_bundle\server-lib\node_modules\fibers\future.js:280
W20210705-15:38:00.657(-5)? (STDERR) throw(ex);
W20210705-15:38:00.657(-5)? (STDERR) ^
W20210705-15:38:00.658(-5)? (STDERR) TypeError: Cannot read property '_handleConnect' of undefined
W20210705-15:38:00.658(-5)? (STDERR) at exposeLivedata (packages\lamhieu_meteorx.js:26:25)
W20210705-15:38:00.659(-5)? (STDERR) at packages\lamhieu_meteorx.js:200:1
W20210705-15:38:00.659(-5)? (STDERR) at packages\lamhieu_meteorx.js:225:4
W20210705-15:38:00.659(-5)? (STDERR) at packages\lamhieu_meteorx.js:233:3
W20210705-15:38:00.660(-5)? (STDERR) at C:\Users\STEELT~1\AppData\Local\Temp\meteor-test-runopwor.np2jra\.meteor\local\build\programs\server\boot.js:401:38
W20210705-15:38:00.660(-5)? (STDERR) at Array.forEach (<anonymous>)
W20210705-15:38:00.661(-5)? (STDERR) at C:\Users\STEELT~1\AppData\Local\Temp\meteor-test-runopwor.np2jra\.meteor\local\build\programs\server\boot.js:226:21
W20210705-15:38:00.661(-5)? (STDERR) at C:\Users\STEELT~1\AppData\Local\Temp\meteor-test-runopwor.np2jra\.meteor\local\build\programs\server\boot.js:464:7
W20210705-15:38:00.661(-5)? (STDERR) at Function.run (C:\Users\STEELT~1\AppData\Local\Temp\meteor-test-runopwor.np2jra\.meteor\local\build\programs\server\profile.js:280:14)
W20210705-15:38:00.662(-5)? (STDERR) at C:\Users\STEELT~1\AppData\Local\Temp\meteor-test-runopwor.np2jra\.meteor\local\build\programs\server\boot.js:463:13
=> Started your app.
=> App running at: http://localhost:3000/
Type Control-C twice to stop.
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.
Process finished with exit code 1
After that, I ran
meteor update again and the error has gone:
Not updating the release, because this app is at a newer release (METEOR@2.3.1-rc.0) than the latest recommended release (METEOR@2.2.1).
Changes to your project's package version selections from updating package versions:
blaze-tools upgraded from 1.1.1 to 1.1.2
caching-html-compiler upgraded from 1.2.0 to 1.2.1
html-tools upgraded from 1.1.1 to 1.1.2
htmljs upgraded from 1.1.0 to 1.1.1
http upgraded from 1.4.3 to 1.4.4
lamhieu:meteorx removed from your project
meteortesting:mocha upgraded from 2.0.1 to 2.0.2
montiapm:agent upgraded from 2.42.0 to 2.43.1
montiapm:meteorx added, version 2.2.0
observe-sequence upgraded from 1.0.16 to 1.0.18
socialize:server-presence upgraded from 1.0.3 to 1.0.4
socialize:user-presence upgraded from 1.0.3 to 1.0.4
spacebars-compiler upgraded from 1.2.1 to 1.3.0
static-html upgraded from 1.3.0 to 1.3.2
templating-tools upgraded from 1.2.0 to 1.2.1
tunguska:reactive-aggregate upgraded from 1.3.3 to 1.3.6
Newer versions of the following indirect dependencies are available:
* http 1.4.4 (2.0.0 is available)
* meteortesting:mocha-core 8.0.1 (8.1.2 is available)
* spacebars 1.0.15 (1.2.0 is available)
These versions may not be compatible with your project.
To update one or more of these packages to their latest
compatible versions, pass their names to `meteor update`,
or just run `meteor update --all-packages`.
The error was due to lamhie:meteorx package, so this was replaced by monitapm:meteorx
IMHO It works fine this release.