BaselineProfileRule.kt
/*
* Copyright 2021 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.benchmark.macro.junit4
import android.Manifest
import androidx.annotation.RequiresApi
import androidx.benchmark.macro.ExperimentalBaselineProfilesApi
import androidx.benchmark.macro.MacrobenchmarkScope
import androidx.benchmark.macro.collectBaselineProfile
import androidx.test.rule.GrantPermissionRule
import org.junit.rules.RuleChain
import org.junit.rules.TestRule
import org.junit.runner.Description
import org.junit.runners.model.Statement
/**
* A [TestRule] that collects Baseline Profiles to be embedded in your APK.
*
* These rules are used at install time to partially pre-compile your application code.
*
* ```
* @ExperimentalBaselineProfilesApi
* @RunWith(AndroidJUnit4::class)
* class BaselineProfileGenerator {
* @get:Rule
* val baselineProfileRule = BaselineProfileRule()
*
* @Test
* fun startup() = baselineProfileRule.collectBaselineProfile(
* packageName = "com.example.app"
* ) {
* pressHome()
* // This block defines the app's critical user journey. Here we are
* // interested in optimizing for app startup, but you can also navigate
* // and scroll through your most important UI.
* startActivityAndWait()
* }
* }
* ```
*
* See the [Baseline Profile Guide](https://developer.android.com/studio/profile/baselineprofiles)
* for more information on creating Baseline Profiles.
*/
@RequiresApi(28)
@ExperimentalBaselineProfilesApi
class BaselineProfileRule : TestRule {
private lateinit var currentDescription: Description
override fun apply(base: Statement, description: Description): Statement {
return RuleChain
.outerRule(GrantPermissionRule.grant(Manifest.permission.WRITE_EXTERNAL_STORAGE))
.around(::applyInternal)
.apply(base, description)
}
private fun applyInternal(base: Statement, description: Description) = object : Statement() {
override fun evaluate() {
currentDescription = description
base.evaluate()
}
}
/**
* Collects baseline profiles for a critical user journey.
* @param packageName Package name of the app for which profiles are to be generated.
* @param [profileBlock] defines the critical user journey.
*/
public fun collectBaselineProfile(
packageName: String,
profileBlock: MacrobenchmarkScope.() -> Unit
) {
collectBaselineProfile(
currentDescription.toUniqueName(),
packageName = packageName,
profileBlock = profileBlock
)
}
private fun Description.toUniqueName() = testClass.simpleName + "_" + methodName
}