Does anyone know how you could create a custom lint rule that would fail if it catches a certain fun...

# android

[Chris Johnson]

Does anyone know how you could create a custom lint rule that would fail if it catches a certain function/function name being used anywhere outside a specified file?

[Chris Johnson]

If this is a channel for nothing but kotlin questions it should probably be renamed to something other than android 🙂 Not quite clear that it's only for kotlin related questions...

[Daniel B Duval]

This one is an interesting question for this one as Android’s custom lint is to be written in Kotlin and not Java 🙂

What you’d need to do is use a extension of Detector() that implements SourceCodeScanner

First, in your override of getApplicableUastTypes, you’d specify listOf(UIMethod::class.java)

Second, in your override of `createUastHandler`you’ll want to implement override fun visitMethod(node: UIMethod)

In this method, you’ll look at the node.name to see it has the method you do not want. The context.getLocation(node) will let you know where you are. You can decide to first look at the node or the location.

Just be aware of the scopes you pass into the Implementation. By default, TEST_SOURCES aren’t in there, so if you want tests, you need to add them.

You can find the official guide here - https://googlesamples.github.io/android-custom-lint-rules/api-guide.html

If you’re not already using custom lint, I’d also suggest that you put `lintPublish. project(':customLintProject')`and lintChecks project(':customLintProject') in a module that all your modules are dependent on in your build script. This will force all projects to pick it up and it can bring the checks into studio.

[Daniel B Duval]

Also, do be aware that if you write tests, the imports in anything you load in via lint().files needs to resolve. E.g., if you have

import androidx.compose.material.OutlinedButton

[Daniel B Duval]

You’ll need to stub it, e.g. https://googlesamples.github.io/android-custom-lint-rules/api-guide.html#lintcheckunittesting/librarydependenciesandstubs

[Chris Johnson]

Thank you for all the information! I'll be looking into these more 🔍