do not include entries from --dart-define-from-file files in the gradle config or environment during build

[andrewkolos]

Fixes #130599 and #136444

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[christopherfujino]

LGTM

[sbatezat]

Just want to mention, as Flutter team is locking every subject related to this big breaking change on GitHub and I'm not using Discord.

The name of this MR is wrong. @andrewkolos you do not have removed entries set with --dart-define-from-file, they are still there, under the 'dart-defines' property, encoded in Base64. Same on Apple side.

Proof of concept:

def dartEnvironmentVariables = [];
if (project.hasProperty('dart-defines')) {
    dartEnvironmentVariables = project.property('dart-defines')
        .split(',')
        .collectEntries { entry ->
            def pair = new String(entry.decodeBase64(), 'UTF-8').split('=')
            [(pair.first()): pair.last()]
        }
}

However, I agree that it was not normal to have different behavior between --dart-define && --dart-define-from-file. I have warned @TatsuUkraine about it here #114297 (comment) but my comment has not been taken into consideration.... many months later here we are.

There is discussions about adding a new key for native build, this is so ridiculous as:

• you only have to revert this commit or document the extraction done above...
• We want these properties available on both native & dart

cc @christopherfujino please take this into consideration

[andrewkolos]

Thanks for your concerns.

• you only have to revert this commit or document the extraction done above...
• We want these properties available on both native & dart

This has been already discussed at great length both on GitHub and offline amongst Flutter contributors. There are no plans to revert this change. Pinging folks is unlikely to change that. I'm also not inclined to document the above workaround. The existence of the definitions in these base64 encoded strings is an undocumented implementation detail (much like the behavior this PR removed). As I've mentioned before, this is not a breaking change per the Flutter project's breaking change policy, although I do believe this change should have been announced (which I've already conceded on another thread on this topic.)

Environment definitions can be set without the need for something like --dart-define-from-file, as I assume folks were already doing before the introduction of --dart-define-from-file. I do understand that it requires extra work to make sure these definitions are synchronized with the ones provided to --dart-define/--dart-define-from-file, but I imagine this is a sufficient workaround.

[andrewkolos]

The tracking issue for re-implementing this functionality is at #139289.