errors << "From non-nullable to nullable breaking change"
                } else if (oldNullability && !newNullability) {
                    warnings << "Nullability changed from nullable to non-nullable"
                }
            } else if (oldNullability != newNullability) {
                errors << "Nullability breaking change"
            }

        } else if (member instanceof JApiConstructor) {

## Expected Behavior
<!--- If you're describing a bug, tell us what should happen -->
<!--- If you're suggesting a change/improvement, tell us how it should work -->

## Current Behavior
<!--- If describing a bug, tell us what happens instead of the expected behavior -->
<!--- If suggesting a change/improvement, explain the difference from current behavior -->

## Possible Solution

            """
        ) {
            assertHasErrors(
                "Field nonFinalField: Nullability breaking change.",
                "Field finalField: From non-nullable to nullable breaking change.",
                "Method com.example.Source.foo(): From non-null returning to null returning breaking change."
            )
            assertHasNoWarning()
            assertHasNoInformation()
        }
    }

    @Test

            listOf(
                Change("org.gradle.api.tasks.AbstractExecTask", "Method org.gradle.api.tasks.AbstractExecTask.getExecResult()"),
                Change("org.gradle.api.AntBuilder", "Class org.gradle.api.AntBuilder"),
                Change("org.gradle.api.file.SourceDirectorySet", "Method org.gradle.api.file.SourceDirectorySet.getOutputDir()"),

        def acceptedChange = changes.acceptedChanges.entrySet().iterator().next()
        def change = acceptedChange.key
        change.type == "org.gradle.api.initialization.ConfigurableIncludedBuild"
        change.member == "Implemented interface org.gradle.api.initialization.IncludedBuild"
        change.changes == ["Interface has been removed"]
        acceptedChange.value == "@Incubating interface has been removed"
    }

                "Method com.example.Source.plus(int,java.util.List): Breaking Kotlin modifier change.",
                "Method com.example.SourceKt.invoke(java.lang.String,int): Breaking Kotlin modifier change.",
                "Method com.example.SourceKt.invoke(long,int): Breaking Kotlin modifier change.",

#### What type of PR is this?

<!--
Add one of the following kinds:
/kind bug
/kind cleanup
/kind documentation
/kind feature

Optionally add one or more of the following kinds if applicable:
/kind api-change
/kind deprecation
/kind failing-test
/kind flake
/kind regression
-->

#### What this PR does / why we need it:

#### Which issue(s) this PR fixes:
<!--

  "durations" : [ {
    "testProject" : "largeJavaMultiProject",
    "linux" : 828
  } ]
}, {
  "scenario" : "org.gradle.performance.regression.buildcache.TaskOutputCachingJavaPerformanceTest.clean assemble for non-abi change with local cache",
  "durations" : [ {
    "testProject" : "largeJavaMultiProject",

    "groups" : [ {
      "testProject" : "largeJavaMultiProject",
      "coverage" : {
        "per_commit" : [ "linux", "windows", "macOs" ]
      }
    } ]
  }, {
    "testId" : "org.gradle.performance.regression.java.JavaIncrementalExecutionPerformanceTest.assemble for non-abi change",
    "groups" : [ {

  - 'API': 5.x/okhttp/okhttp3/
  - 'Change Logs':
    - 'Change Log': changelogs/changelog.md
    - '4.x Change Log': changelogs/changelog_4x.md
    - 'Upgrading to OkHttp 4': changelogs/upgrading_to_okhttp_4.md
    - '3.x Change Log': changelogs/changelog_3x.md
    - '2.x Change Log': changelogs/changelog_2x.md
    - '1.x Change Log': changelogs/changelog_1x.md
  - 'Contributing':