Fixes #1454 by setting the msrv

[patmuk]

Changes

• fixes [Bug] cargo install 'flutter_rust_bridge_codegen@^2.0.0-dev.2' has compilation errors #1454 by adding the MSRV to fab_codegen

Checklist

• An issue to be fixed by this PR is listed above.
• New tests are added to ensure new features are working. End-to-end tests are usually in the ./frb_example/pure_dart example, more specifically, rust/src/api/whatever.rs and test/api/whatever_test.dart. => test is in ci
• ./frb_internal precommit --mode slow (or fast) is run (it internal runs code generator, does auto formatting, etc).
• If this PR adds/changes features, documentations (in the ./website folder) are updated.
• CI is passing. (Operations are reproducible using corresponding ./frb_internal something commands shown in CI.)
  => all passes, except "Benchmark" jobs. They did not pass before this changes either.

Remark for PR creator

• The ci test installs "crate msrv", which verifies that the version set is correct. It can be used to find the correct version number as well - but that should be done locally, not in ci - as the MSRV usually doesn't change ofter. The ci fails only when the MSRV is not working anymore, by installing that version and running cargo check.
• This PR adds a MSRV to frb_codegen only, no other rust crates.
• There are two ways to specify the MSRV in the cargo.toml:
  • [platform.rust-version] (which I choose) and
  • [platform.metadata.MSRV]

[welcome]

Hi! Thanks for opening this pull request! 😄

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (0f344d2) 94.31% compared to head (a880abe) 99.20%.
Report is 304 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1463      +/-   ##
==========================================
+ Coverage   94.31%   99.20%   +4.88%     
==========================================
  Files         356      341      -15     
  Lines       13560    13141     -419     
==========================================
+ Hits        12789    13036     +247     
+ Misses        771      105     -666     

☔ View full report in Codecov by Sentry.
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[patmuk]

The ci build has some issues I would need some help with:

1. The job Test :: Flutter :: Native:: iOS fails!
   The error is

[   +7 ms] executing: xcrun simctl spawn 90F52CAA-A5C8-4946-8432-DF0D4EF688AC log stream --style json --predicate eventType = logEvent AND processImagePath ENDSWITH "Runner" AND (senderImagePath ENDSWITH "/Flutter" OR senderImagePath ENDSWITH "/libswiftCore.dylib" OR processImageUUID == senderImageUUID) AND NOT(eventMessage CONTAINS ": could not find icon for representation -> com.apple.") AND NOT(eventMessage BEGINSWITH "assertion failed: ") AND NOT(eventMessage CONTAINS " libxpc.dylib ")

I don't understand how the changes lead to that - probably rust 1.74.0 is not the MSRV, but we need a higher number? Which are you using as the default in ci?

2. The ci runs take much longer now! 53m! Though other (successful) runs take around 40 min - maybe that is a normal variation?

3. I introduced a few warnings we should get rid of. Probably I am using a wrong settings for

    - uses: actions/checkout@v2
    - name: Install Rust
      uses: actions-rs/toolchain@v1

?

The warnings are:

[Test :: FRB Codegen :: MSRV](https://github.com/fzyzcjy/flutter_rust_bridge/actions/runs/7282632799/job/19845306520)
The following actions uses node12 which is deprecated and will be forced to run on node16: actions/checkout@v2, actions-rs/toolchain@v1. For more info: https://github.blog/changelog/2023-06-13-github-actions-all-actions-will-run-on-node16-instead-of-node12-by-default/

[Test :: FRB Codegen :: MSRV](https://github.com/fzyzcjy/flutter_rust_bridge/actions/runs/7282632799/job/19845306520#step:3:30)
The `set-output` command is deprecated and will be disabled soon. Please upgrade to using Environment Files. For more information see: https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

(they are repeated a few times)

[patmuk]

oh, 1. could be because of #1464. Can you maybe verify that it runs locally? I haven't set up docker, etc.

[fzyzcjy]

1. could be because of Fix iOS CI which once in a while fails (flaky), while it works well locally #1464.

Usually, if one of the two ios test fails, it is just flaky, and ignore it. Also you can "bump" the CI by commiting some nonsense (e.g. a space change)

The ci runs take much longer now! 53m! Though other (successful) runs take around 40 min - maybe that is a normal variation?

No worries, run more as you progress, and we will see whether it is just a variation

The following actions uses node12

Again no worries until the last step. The existing CI has some warning as well due to 3rd party actions

[patmuk]

Ok, super - will do so!

[fzyzcjy]

Oh please ping me whenever I do not reply within a day! I did not see your reply above until now (when I open this page to refer to another issue).

[fzyzcjy]

Good job!

[fzyzcjy]

It may be great if we can lower the MSRV by fixing some trivial compile errors ;)

[patmuk]

Hmmm - I personally don't mind, as I like to use the latest version.
But I suggest opening another issue for that. In #1454 you can get an impression of what kind of changes would have to be made (that was with rust 1.71., the compiler complained about pup (crate) mostly).
I assume that would require a redesign of the modularization.
IMHO: Not worth it, would not do that unless somebody complains.

I got to the MSRV of 1.74.0 by using cargo msrv, which performs a bisect search. So it won't compile to anything lower without changes to the code.
I would leave it as it, and only of somebody raises an issue needing a lower version work on specifically supporting from that version on.

[fzyzcjy]

I suggest opening another issue for that

Sure! Then let's keep this PR simple and atomic.

[patmuk]

Oh please ping me whenever I do not reply within a day! I did not see your reply above until now (when I open this page to refer to another issue).

Surely! No worries, I thought you might have a Christmas break (if you celebrate it).

[patmuk]

Good job!

Thanks :) I am taking care of your remarks now.

[fzyzcjy]

Surely! No worries, I thought you might have a Christmas break (if you celebrate it).

No, as you can see from my github profile, I am on github 365 days per year ;)

[welcome]

Hi! Congrats on merging your first pull request! 🎉

[fzyzcjy]

@all-contributors please add @patmuk for code

[allcontributors]

@fzyzcjy

I've put up a pull request to add @patmuk! 🎉