Scala: use release flag. Clean up compiler options.

Author: SimY4

xpath-to-xml-scala/build-2.12.gradle

@@ -89,13 +89,12 @@ tasks.withType(ScalaCompile) {
                 '-Yno-adapted-args',                 // Do not adapt an argument list (either by inserting () or creating a tuple) to match the receiver.
                 '-Xsource:3',                        // Turn on future language features.
                 '-target:jvm-1.8',
+                '-opt:l:method',
+                '-opt:l:inline',
+                '-opt-inline-from:com.github.simy4.xpath.scala.navigator.**,com.github.simy4.xpath.scala.syntax.**',
         ]
-        if (!JavaVersion.current().isJava12Compatible()) {
-            additionalParameters += [
-                    '-opt:l:method',
-                    '-opt:l:inline',
-                    '-opt-inline-from:com.github.simy4.xpath.scala.navigator.**,com.github.simy4.xpath.scala.syntax.**',
-            ]
+        if (JavaVersion.current().isJava9Compatible()) {
+            additionalParameters << '-release' << '8'
         }
     }
 }

xpath-to-xml-scala/build-2.13.gradle

@@ -87,13 +87,12 @@ tasks.withType(ScalaCompile) {
                 '-Wnumeric-widen',                   // Warn when numerics are widened.
                 '-Xsource:3',                        // Turn on future language features.
                 '-target:jvm-1.8',
+                '-opt:l:method',
+                '-opt:l:inline',
+                '-opt-inline-from:com.github.simy4.xpath.scala.navigator.**,com.github.simy4.xpath.scala.syntax.**',
         ]
-        if (!JavaVersion.current().isJava12Compatible()) {
-            additionalParameters += [
-                    '-opt:l:method',
-                    '-opt:l:inline',
-                    '-opt-inline-from:com.github.simy4.xpath.scala.navigator.**,com.github.simy4.xpath.scala.syntax.**',
-            ]
+        if (!JavaVersion.current().isJava9Compatible()) {
+            additionalParameters << '-release' << '8'
         }
     }
 }

xpath-to-xml-scala/build-3.gradle

@@ -30,14 +30,6 @@ javadocJar {
     from scaladoc
 }
 
-scaladoc {
-    scalaDocOptions.with {
-        additionalParameters = [
-                '-language:macros,implicitConversions'
-        ]
-    }
-}
-
 tasks.withType(ScalaCompile) {
     scalaCompileOptions.with {
         deprecation = true
@@ -50,7 +42,11 @@ tasks.withType(ScalaCompile) {
                 '-language:macros,implicitConversions',
                 '-Xfatal-warnings',                     // Fail the compilation if there are any warnings.
                 '-source:3.1',                          // Turn on future language features.
-                '-Xtarget:8',
         ]
+        if (JavaVersion.current().isJava9Compatible()) {
+            additionalParameters << '-release' << '8'
+        } else {
+            additionalParameters << '-Xtarget:8'
+        }
     }
 }