Bridge binary incompatibility in Gradle 4.3 for TaskInputs#property()

* Fixes #34

Author: mannodermaus

android-junit5/src/main/groovy/de/mannodermaus/gradle/plugins/junit5/GroovyInterop.groovy

@@ -1,8 +1,10 @@
 package de.mannodermaus.gradle.plugins.junit5
 
 import com.android.annotations.NonNull
+import com.android.annotations.Nullable
 import com.android.build.gradle.api.BaseVariant
 import com.android.build.gradle.internal.variant.BaseVariantData
+import org.gradle.api.tasks.TaskInputs
 import org.junit.platform.gradle.plugin.FiltersExtension
 import org.junit.platform.gradle.plugin.SelectorsExtension
 
@@ -15,6 +17,27 @@ class GroovyInterop {
   // No instances
   private GroovyInterop() { throw new AssertionError() }
 
+  /**
+   * Add the provided key-value pair to the given TaskInputs object.
+   * Gradle 4.3 included a binary-incompatible change to this method's
+   * return type, which fails for clients running older versions of the
+   * build system.
+   *
+   * Refer to the related issue on GitHub:
+   * https://github.com/mannodermaus/android-junit5/issues/34
+   *
+   * FIXME Once the plugin's minimal Gradle version reaches 4.3, remove this.
+   *
+   * @param inputs TaskInputs to update
+   * @param key Key of the property to set
+   * @param value Value of the property to set
+   * @return Self reference with a backwards-compatible type
+   */
+  @NonNull
+  static TaskInputs taskInputs_safeProperty(TaskInputs inputs, String key, @Nullable Object value) {
+    return inputs.property(key, value) as TaskInputs
+  }
+
   /**
    * Obtains the VariantData of the provided Variant.
    * BaseVariant#variantData is protected

android-junit5/src/main/kotlin/de/mannodermaus/gradle/plugins/junit5/Interop.kt

@@ -2,6 +2,7 @@ package de.mannodermaus.gradle.plugins.junit5
 
 import com.android.build.gradle.api.BaseVariant
 import com.android.build.gradle.internal.variant.BaseVariantData
+import org.gradle.api.tasks.TaskInputs
 import org.junit.platform.gradle.plugin.FiltersExtension
 import org.junit.platform.gradle.plugin.SelectorsExtension
 
@@ -23,3 +24,6 @@ fun FiltersExtension.getExcludeClassNamePatterns(): List<String> =
 
 val BaseVariant.variantData: BaseVariantData
   get() = GroovyInterop.baseVariant_variantData(this)
+
+fun TaskInputs.safeProperty(key: String, value: Any?) =
+    GroovyInterop.taskInputs_safeProperty(this, key, value)

android-junit5/src/main/kotlin/de/mannodermaus/gradle/plugins/junit5/tasks/UnitTest.kt

@@ -16,6 +16,7 @@ import de.mannodermaus.gradle.plugins.junit5.junit5Info
 import de.mannodermaus.gradle.plugins.junit5.packages
 import de.mannodermaus.gradle.plugins.junit5.providers.DirectoryProvider
 import de.mannodermaus.gradle.plugins.junit5.providers.classDirectories
+import de.mannodermaus.gradle.plugins.junit5.safeProperty
 import de.mannodermaus.gradle.plugins.junit5.selectors
 import de.mannodermaus.gradle.plugins.junit5.tags
 import de.mannodermaus.gradle.plugins.junit5.variantData
@@ -147,24 +148,24 @@ open class AndroidJUnit5UnitTest : JavaExec() {
     private fun configureTaskInputs(
         task: AndroidJUnit5UnitTest,
         junit5: AndroidJUnitPlatformExtension) {
-      task.inputs.property("enableStandardTestTask", junit5.enableStandardTestTask)
-      task.inputs.property("configurationParameters", junit5.configurationParameters)
-      task.inputs.property("selectors.uris", junit5.selectors.uris)
-      task.inputs.property("selectors.files", junit5.selectors.files)
-      task.inputs.property("selectors.directories", junit5.selectors.directories)
-      task.inputs.property("selectors.packages", junit5.selectors.packages)
-      task.inputs.property("selectors.classes", junit5.selectors.classes)
-      task.inputs.property("selectors.methods", junit5.selectors.methods)
-      task.inputs.property("selectors.resources", junit5.selectors.resources)
-      task.inputs.property("selectors.modules", junit5.selectors.modules)
-      task.inputs.property("filters.engines.include", junit5.filters.engines.include)
-      task.inputs.property("filters.engines.exclude", junit5.filters.engines.exclude)
-      task.inputs.property("filters.tags.include", junit5.filters.tags.include)
-      task.inputs.property("filters.tags.exclude", junit5.filters.tags.exclude)
-      task.inputs.property("filters.includeClassNamePatterns",
+      task.inputs.safeProperty("enableStandardTestTask", junit5.enableStandardTestTask)
+      task.inputs.safeProperty("configurationParameters", junit5.configurationParameters)
+      task.inputs.safeProperty("selectors.uris", junit5.selectors.uris)
+      task.inputs.safeProperty("selectors.files", junit5.selectors.files)
+      task.inputs.safeProperty("selectors.directories", junit5.selectors.directories)
+      task.inputs.safeProperty("selectors.packages", junit5.selectors.packages)
+      task.inputs.safeProperty("selectors.classes", junit5.selectors.classes)
+      task.inputs.safeProperty("selectors.methods", junit5.selectors.methods)
+      task.inputs.safeProperty("selectors.resources", junit5.selectors.resources)
+      task.inputs.safeProperty("selectors.modules", junit5.selectors.modules)
+      task.inputs.safeProperty("filters.engines.include", junit5.filters.engines.include)
+      task.inputs.safeProperty("filters.engines.exclude", junit5.filters.engines.exclude)
+      task.inputs.safeProperty("filters.tags.include", junit5.filters.tags.include)
+      task.inputs.safeProperty("filters.tags.exclude", junit5.filters.tags.exclude)
+      task.inputs.safeProperty("filters.includeClassNamePatterns",
           junit5.filters.getIncludeClassNamePatterns())
-      task.inputs.property("filters.packages.include", junit5.filters.packages.include)
-      task.inputs.property("filters.packages.exclude", junit5.filters.packages.exclude)
+      task.inputs.safeProperty("filters.packages.include", junit5.filters.packages.include)
+      task.inputs.safeProperty("filters.packages.exclude", junit5.filters.packages.exclude)
 
       junit5.logManager?.let {
         task.systemProperty("java.util.logging.manager", junit5.logManager)