* limitations under the License.
 */

package gradlebuild.binarycompatibility

import org.gradle.kotlin.dsl.*
import org.gradle.testkit.runner.BuildResult
import org.gradle.testkit.runner.GradleRunner
import org.gradle.testkit.runner.UnexpectedBuildFailure
import org.hamcrest.CoreMatchers
import org.hamcrest.MatcherAssert.assertThat
import org.junit.Assert.assertFalse
import org.junit.Assert.assertTrue

import okhttp3.internal.threadFactory

/**
 * A set of worker threads that are shared among a set of task queues.
 *
 * Use [INSTANCE] for a task runner that uses daemon threads. There is not currently a shared
 * instance for non-daemon threads.
 *
 * The task runner is also responsible for releasing held threads when the library is unloaded.
 * This is for the benefit of container environments that implement code unloading.
 *

    val os = Os.LINUX
    val buildTypeThis = this
    val testProject = "smallJavaMultiProject"

    fun BuildSteps.gradleStep(tasks: List<String>) {
        gradleWrapper {
            name = "GRADLE_RUNNER"
            gradleParams = (
                tasks +
                    buildToolGradleParameters(isContinue = false)
                ).joinToString(separator = " ")
            skipConditionally()
        }
    }

lipracer, Louis Sugy, Lu Teng, Mahmoud Abuzaina, Malcolm Slaney, Malik Shahzad Muzaffar, Marek Šuppa, Matt Conley, Michael Melesse, Milos Puzovic, mohantym, Nathan John Sircombe, Nathan Luehr, Nilesh Agarwalla, Patrice Vignola, peterjc123, Philip Turner, Rajeshwar Reddy T, Robert Kalmar, Rodrigo Formigone, Rohit Santhanam, rui, Sachin Muradi, Saduf2019, sandip, Scott Leishman, Serge Panev, Shi,Guangyong, Srinivasan Narayanamoorthy, stanley, Steven I Reeves, stevenireeves, sushreebarsa, Tamas Bela...

[2020-01-01 00:00:00] << 0x00000003   288 DATA
[2020-01-01 00:00:00] << 0x00000003     0 DATA          END_STREAM
[2020-01-01 00:00:00] << 0x00000000     8 GOAWAY
[2020-01-01 00:00:05] << 0x00000000     8 GOAWAY
```

### Task Runner Logging 

This logs task enqueues, starts, and finishes.

```
[2020-01-01 00:00:00] Q10000 scheduled after   0 µs: OkHttp ConnectionPool
[2020-01-01 00:00:00] Q10000 starting              : OkHttp ConnectionPool

    killProcessStep(KILL_LEAKED_PROCESSES_FROM_PREVIOUS_BUILDS, os, arch)

    (1..10).forEach { idx ->
        steps {
            gradleWrapper {
                name = "GRADLE_RUNNER_$idx"
                tasks = "%$testTaskParameterName% -PrerunAllTests --tests %$testNameParameterName% %$testTaskOptionsParameterName%"
                gradleParams = parameters

        "CODEQL_JAVA_HOME",
        "CODEQL_EXTRACTOR_JAVA_SCRATCH_DIR",
        "CODEQL_ACTION_RUN_MODE",
        "CODEQL_ACTION_VERSION",
        "CODEQL_DIST",
        "CODEQL_PLATFORM",
        "CODEQL_RUNNER"
    )

    private
    val architecture = System.getProperty("os.arch").toLowerCase()

    val isCiServer = CI_ENVIRONMENT_VARIABLE in System.getenv()
    val isTravis = "TRAVIS" in System.getenv()

  /** How many times a new task has been started. Guarded by [TaskRunner.lock]. */
  private var contextSwitchCount = 0

  /** Guarded by [TaskRunner.lock]. */
  private var activeThreads = 0

  /** A task runner that posts tasks to this fake. Tasks won't be executed until requested. */
  val taskRunner: TaskRunner =
    TaskRunner(
      object : TaskRunner.Backend {
        override fun execute(
          taskRunner: TaskRunner,

class ConnectionPoolTest {
  private val routePlanner = FakeRoutePlanner()
  private val factory = routePlanner.factory
  private val taskFaker = routePlanner.taskFaker
  private val peer = MockHttp2Peer()

  /** The fake task runner prevents the cleanup runnable from being started.  */
  private val addressA = factory.newAddress("a")
  private val routeA1 = factory.newRoute(addressA)
  private val addressB = factory.newAddress("b")

Everyone before you is waiting for their burgers to be ready before leaving the counter because each of the 8 cashiers goes and prepares the burger right away before getting the next order.

<img src="/img/async/parallel-burgers/parallel-burgers-01.png" class="illustration">