Modify configs earlier; Support sourceCompatibility

src/main/groovy/com/jaredsburrows/checkerframework/CheckerPlugin.groovy

@@ -35,22 +35,23 @@ final class CheckerPlugin implements Plugin<Project> {
 
   @Override void apply(Project project) {
     CheckerExtension userConfig = project.extensions.create("checkerFramework", CheckerExtension)
-
-    project.gradle.projectsEvaluated {
-      AppliedPlugin prereq = (ANDROID_IDS + "java").findResult(project.pluginManager.&findPlugin)
-      if (!prereq) LOG.warn('No android or java plugins found, checker compiler options will not be applied.')
-      else {
-        LOG.info('Found plugin {}, applying checker compiler options.', prereq.id)
+    boolean applied = false
+    (ANDROID_IDS + "java").each { id ->
+      project.pluginManager.withPlugin(id) {
+        LOG.info('Found plugin {}, applying checker compiler options.', id)
         configureProject(project, userConfig)
+        if (!applied) applied = true
       }
     }
+    project.gradle.projectsEvaluated {
+      if (!applied) LOG.warn('No android or java plugins found, checker compiler options will not be applied.')
+    }
   }
 
   private static configureProject(Project project, CheckerExtension userConfig) {
     JavaVersion javaVersion =
         project.extensions.findByName('android')?.compileOptions?.sourceCompatibility ?:
-        project.convention.findByName('jdk')?.sourceCompatibility ?:
-        JavaVersion.current()
+        project.property('sourceCompatibility')
 
     // Check for Java 7 or Java 8 to make sure to get correct annotations dependency
     def jdkVersion
@@ -89,23 +90,25 @@ final class CheckerPlugin implements Plugin<Project> {
     }
 
     // Apply checker to project
-    project.tasks.withType(AbstractCompile).all { compile ->
-      compile.options.annotationProcessorPath = project.configurations.checkerFramework
-      compile.options.compilerArgs = [
-        "-Xbootclasspath/p:${project.configurations.checkerFrameworkAnnotatedJDK.asPath}".toString()
-      ]
-      if (!userConfig.checkers.empty) {
-        compile.options.compilerArgs << "-processor" << userConfig.checkers.join(",")
-      }
+    project.gradle.projectsEvaluated {
+      project.tasks.withType(AbstractCompile).all { compile ->
+        compile.options.annotationProcessorPath = project.configurations.checkerFramework
+        compile.options.compilerArgs = [
+          "-Xbootclasspath/p:${project.configurations.checkerFrameworkAnnotatedJDK.asPath}".toString()
+        ]
+        if (!userConfig.checkers.empty) {
+          compile.options.compilerArgs << "-processor" << userConfig.checkers.join(",")
+        }
 
-      ANDROID_IDS.each { id ->
-        project.plugins.withId(id) {
-          options.bootClasspath = System.getProperty("sun.boot.class.path") + ":" + options.bootClasspath
-          options.bootClasspath = "${project.configurations.checkerFrameworkJavac.asPath}:".toString() + ":" + options.bootClasspath
+        ANDROID_IDS.each { id ->
+          project.plugins.withId(id) {
+            options.bootClasspath = System.getProperty("sun.boot.class.path") + ":" + options.bootClasspath
+            options.bootClasspath = "${project.configurations.checkerFrameworkJavac.asPath}:".toString() + ":" + options.bootClasspath
+          }
         }
+        options.fork = true
+        //        options.forkOptions.jvmArgs += ["-Xbootclasspath/p:${project.configurations.checkerFrameworkJavac.asPath}"]
       }
-      options.fork = true
-      //        options.forkOptions.jvmArgs += ["-Xbootclasspath/p:${project.configurations.checkerFrameworkJavac.asPath}"]
     }
   }
 }

src/test/groovy/com/jaredsburrows/checkerframework/CheckerPluginSpec.groovy

@@ -115,4 +115,68 @@ final class CheckerPluginSpec extends BaseSpecification {
     gradleVersion << TESTED_GRADLE_VERSIONS
   }
 
+  def 'with relevant plugin loaded subsequently, compiler settings are applied'() {
+    given:
+    buildFile <<
+      """
+        plugins {
+          id 'com.jaredsburrows.checkerframework'
+          id 'java'
+        }
+
+        repositories {
+          maven {
+            url "${getClass().getResource("/maven/").toURI()}"
+          }
+        }
+      """.stripIndent().trim()
+
+    when:
+    BuildResult result = GradleRunner.create()
+      .withGradleVersion(gradleVersion)
+      .withProjectDir(testProjectDir.root)
+      .withPluginClasspath()
+      .withArguments('--info')
+      .build()
+
+    then:
+    result.output.contains('applying checker compiler options')
+
+    where:
+    gradleVersion << TESTED_GRADLE_VERSIONS
+  }
+
+  def 'with resolved configuration dependencies, compilation settings are still applied'() {
+    given:
+    buildFile <<
+      """
+        plugins {
+          id 'com.jaredsburrows.checkerframework'
+          id 'java'
+          id 'application'
+        }
+
+        repositories {
+          maven {
+            url "${getClass().getResource("/maven/").toURI()}"
+          }
+        }
+        // Trigger resolution of compile classpath
+        println project.sourceSets.main.compileClasspath as List
+      """.stripIndent().trim()
+
+    when:
+    BuildResult result = GradleRunner.create()
+      .withGradleVersion(gradleVersion)
+      .withProjectDir(testProjectDir.root)
+      .withPluginClasspath()
+      .withArguments('--info')
+      .build()
+
+    then:
+    result.output.contains('applying checker compiler options')
+
+    where:
+    gradleVersion << TESTED_GRADLE_VERSIONS
+  }
 }