Android Studio Build Analyzer warns about "Always-Run Tasks"

[tmcguire]

It looks like the cargoBuild<Target> tasks are always run when running gradle, because they don't specify an output. See this screenshot from Android Studio:

[ncalexan]

I think this could be improved, but I don't quite know how to do it myself. What we need is to add some annotated fields to the CargoBuildTask instances and set them with the information from https://github.com/mozilla/rust-android-gradle/blob/6e553c13ef2d9bb40b58a7675b96e0757d1b0443/plugin/src/main/kotlin/com/nishtahir/CargoBuildTask.kt#L52-L67.

The hard thing here is having the dynamic values of the various configuration options set at the right times so that the annotated fields have the correct values when inspected.

[ncalexan]

I'll add that these tasks are expected to always run but to be very fast, because cargo build --target ... itself does input/output tracking.

[tmcguire]

Also the following warning is printed when running ./gradlew assembleDebug from command-line, I guess it's related:

> Task :<redacted>:cargoBuildArm
Property 'toolchain' is not annotated with an input or output annotation. This behaviour has been deprecated and is scheduled to be removed in Gradle 7.0. See https://docs.gradle.org/6.5/userguide/more_about_tasks.html#sec:up_to_date_checks for more details.```

I'll add that these tasks are expected to always run but to be very fast, because cargo build --target ... itself does input/output tracking.

Right, it is quite fast. I guess the issues for me are:

• Warnings in the project
• Even when cargo doesn't rebuild anything, we still see its output, making things a bit more verbose

[SupernaviX]

When I upgraded to Gradle 7, I wasn't able to build my project anymore because of this. It looks like input/output annotations are required by gradle now, not just recommended.

Edit: never mind! the new plugin version (0.9.0) somehow builds successfully.

[ncalexan]

~When I upgraded to Gradle 7, I wasn't able to build my project anymore because of this. It looks like input/output annotations are required by gradle now, not just recommended.~

Edit: never mind! the new plugin version (0.9.0) somehow builds successfully.

Woot woot! The new plugin version specifically added support for newer Gradle and Android-Gradle Plugin versions, so I'm thrilled that it's working as expected.

As to the actual content of this ticket, these always-run tasks are by design: only Cargo itself can determine if the task needs to run :(