Fix flaky CacheProviderTest (#8684)

javaagent-tooling/src/test/groovy/io/opentelemetry/javaagent/tooling/CacheProviderTest.groovy

@@ -7,7 +7,6 @@ package io.opentelemetry.javaagent.tooling
 
 import io.opentelemetry.javaagent.tooling.muzzle.AgentCachingPoolStrategy
 import net.bytebuddy.description.type.TypeDescription
-import net.bytebuddy.dynamic.ClassFileLocator
 import net.bytebuddy.pool.TypePool
 import spock.lang.Specification
 
@@ -39,6 +38,8 @@ class CacheProviderTest extends Specification {
  expect:
  key1.hashCode() == key2.hashCode()
  key1.equals(key2)
+ // ensures that loader isn't collected
+ loader != null
  }
 
  def "key different ref equivalence"() {
@@ -56,6 +57,8 @@ class CacheProviderTest extends Specification {
 
  key1.hashCode() == key2.hashCode()
  key1.equals(key2)
+ // ensures that loader isn't collected
+ loader != null
  }
 
  def "key mismatch -- same loader - diff name"() {
@@ -70,6 +73,8 @@ class CacheProviderTest extends Specification {
  // not strictly guaranteed -- but important for performance
  fooKey.hashCode() != barKey.hashCode()
  !fooKey.equals(barKey)
+ // ensures that loader isn't collected
+ loader != null
  }
 
  def "key mismatch -- same name - diff loader"() {
@@ -89,6 +94,9 @@ class CacheProviderTest extends Specification {
  // not strictly guaranteed -- but important for performance
  fooKey1.hashCode() != fooKey2.hashCode()
  !fooKey1.equals(fooKey2)
+ // ensures that loader isn't collected
+ loader1 != null
+ loader2 != null
  }
 
  def "test basic caching"() {
@@ -105,6 +113,8 @@ class CacheProviderTest extends Specification {
  then:
  // not strictly guaranteed, but fine for this test
  cacheProvider.find("foo") != null
+ // ensures that loader isn't collected
+ loader != null
  }
 
  def "test loader equivalence"() {
@@ -125,6 +135,9 @@ class CacheProviderTest extends Specification {
  cacheProvider1B.find("foo") != null
 
  cacheProvider1A.find("foo").is(cacheProvider1B.find("foo"))
+
+ // ensures that loader isn't collected
+ loader1 != null
  }
 
  def "test loader separation"() {
@@ -147,26 +160,17 @@ class CacheProviderTest extends Specification {
  cacheProvider2.find("foo") != null
 
  !cacheProvider1.find("foo").is(cacheProvider2.find("foo"))
+
+ // ensures that loader isn't collected
+ loader1 != null
+ loader2 != null
  }
 
  static newVoid() {
- return new TypePool.Resolution.Simple(TypeDescription.VOID)
+ return new TypePool.Resolution.Simple(TypeDescription.ForLoadedType.of(void.class))
  }
 
  static newClassLoader() {
  return new URLClassLoader([] as URL[], (ClassLoader) null)
  }
-
- static newLocator() {
- return new ClassFileLocator() {
- @Override
- ClassFileLocator.Resolution locate(String name) throws IOException {
- return null
- }
-
- @Override
- void close() throws IOException {
- }
- }
- }
 }