[maps-android] store japicmp report to compare against (#6451)

---------

Co-authored-by: Ramon <[email protected]>
GitOrigin-RevId: 9a1e22a9a47aa04d793e55ebfe0dc7a73a730e8f

Author: 2 people

mapbox-convention-plugin/src/main/kotlin/com/mapbox/maps/gradle/plugins/extensions/MapboxJApiCmpExtension.kt

@@ -9,6 +9,9 @@ import japicmp.model.JApiField
 import japicmp.model.JApiMethod
 import javassist.CtMethod
 import me.champeau.gradle.japicmp.JapicmpTask
+import me.champeau.gradle.japicmp.report.RichReportData
+import me.champeau.gradle.japicmp.report.RichReportRenderer
+import me.champeau.gradle.japicmp.report.Severity
 import me.champeau.gradle.japicmp.report.Violation
 import me.champeau.gradle.japicmp.report.stdrules.AbstractRecordingSeenMembers
 import me.champeau.gradle.japicmp.report.stdrules.BinaryIncompatibleRule
@@ -21,6 +24,7 @@ import org.gradle.api.publish.maven.MavenPublication
 import org.gradle.api.tasks.Exec
 import org.gradle.kotlin.dsl.property
 import org.gradle.language.base.plugins.LifecycleBasePlugin
+import java.io.File
 import java.nio.file.Files
 import javax.inject.Inject
 
@@ -198,8 +202,9 @@ public abstract class MapboxJApiCmpExtension @Inject constructor(objects: Object
         addDefaultRules.set(true)
         addSetupRule(RecordSeenMembersSetup::class.java)
         addRule(InternalFilterRule::class.java)
-        destinationDir.set(rootProject.layout.buildDirectory.dir("reports/japi/"))
-        reportName.set("${project.path.drop(1)}.html")
+        destinationDir.set(rootProject.layout.projectDirectory.dir("japicmp-report/"))
+        reportName.set("${project.path.drop(1)}.txt")
+        renderer(CompatibilityReportRenderer::class.java)
       }
 
       htmlOutputFile.set(
@@ -208,6 +213,33 @@ public abstract class MapboxJApiCmpExtension @Inject constructor(objects: Object
     }
   }
 
+  /**
+   * Custom renderer to write compatibility violations to a file.
+   */
+  internal class CompatibilityReportRenderer : RichReportRenderer {
+    override fun render(
+      destinationDir: File?,
+      data: RichReportData?
+    ) {
+      // we only care about breaking changes
+      // otherwise report might be noisy since japicmp will report info and accepted changes too
+      val violations = data?.violations?.map { it.value }?.flatten()
+        ?.filter { it.severity == Severity.error }
+        ?.sortedBy { it.toString() }
+
+      if (violations.isNullOrEmpty()) {
+        // remove destination file as it'll be empty otherwise
+        destinationDir?.delete()
+        return
+      }
+      destinationDir?.bufferedWriter().use { writer ->
+        violations.forEach { violation ->
+          writer?.appendLine(violation.toString())
+        }
+      }
+    }
+  }
+
   internal companion object {
     private val semverRegex = "^(0|[1-9]\\d*)\\.(0|[1-9]\\d*)\\.(0|[1-9]\\d*)".toRegex()
   }