Replying to myself, here's the relevant diff:

- If an option is `mandatory` but not provided, the parser throws an
- [`ArgParserException`][ArgParserException].
+ If an option is `mandatory` but not provided, the results object throws an
+ [`ArgumentError`][ArgumentError] on retrieval.

(From this change)

(According to pub, package:args got published "2 hours ago", which matches the time of the first change that failed in flutter/packages)

What is different between --changelog and --version?

How come this test is not failing in a similar fashion? fails if --version is missing (L78)

Ah, good catch. It turns out that test is subtly wrong, because changelog is blank, and that's also a failure case. So the test is failing with a UsageException thrown by our code because changelog is blank and that's evidently happening before the ArgumentError. I'll add a fix to that test.

Linux/Window repo_tools_tests fails with args: 2.4.2. Is CI engine uses tools different from flutter/packages main?
but flutter/packages are bundled with tools depending on args: ^2.1.0 and sdk: '>=2.14.0 <4.0.0'

So i suggest for universal:

      Error? commandError;
      Exception? commandException;
      await runCapturingPrint(runner, <String>[
        'update-release-info',
        '--version=next',
      ], errorHandler: (Error e) {
        commandError = e;
      }, exceptionHandler: (Exception e) {
        commandException = e;
      });

      expect(
        commandError is ArgumentError || commandException is UsageException,
        isTrue,
      );

flutter/packages are bundled with tools depending on args: ^2.1.0

Can we update the dependency to args: ^2.4.2?

flutter/packages are bundled with tools depending on args: ^2.1.0

Can we update the dependency to args: ^2.4.2?

I considered that when writing the PR, but it requires Dart 2.19, so we'd have to drop the 3.3 legacy tests. I was just going to ignore this since we unit test the tools on master.

Linux/Window repo_tools_tests fails with args: 2.4.2.

That is what this PR fixes, as discussed in previous comments.

Is CI engine uses tools different from flutter/packages main?

I don't understand the question.

So i suggest for universal

Why? Who is running the flutter/packages repo tools' unit tests with Flutter 3.3 or earlier?

I have my PR and i trying to deal with tool/test.

1. Error log shows arg_results.dart 70:7 - it is from args: 2.4.2, but in my PR there is unchanged args: ^2.1.0

2. Also it show source of expect error as test/update_release_info_command_test.dart 54

3. But there is my PR peace of tools, and there is no significal code at line 54:

So, CI runs not PR's tools, and checks no PR's code.

LUCI had some kind of meltdown so everything is red, but I re-ran the repo_tools_tests runs and they are green. Since this is only tool unit test, and thus incapable of affecting anything else, landing with red tests to fix the tree.

I have my PR and i trying to deal with tool/test.

The only way to deal with out-of-band failures is to wait for them to be fixed (as has now happened), then rebase/merge the latest main.

1. Error log shows arg_results.dart 70:7 - it is from args: 2.4.2, but in my PR there is unchanged args: ^2.1.0

Yes, ^2.1.0 includes 2.4.2 in its range.

So, CI runs not PR's tools, and checks no PR's code.

I don't understand how you reached that conclusion, but it is not correct.