Use more robust method of checking for headless

Author: ERSUCC

build.sbt

@@ -10,7 +10,7 @@ isSnapshot := true
 
 netLogoExtName      := "ls"
 netLogoClassManager := "org.nlogo.ls.LevelSpace"
-netLogoVersion      := "7.0.0-RC1-e8801f2"
+netLogoVersion      := "7.0.0-424b50b"
 netLogoTestExtras   += (baseDirectory.value / "test")
 
 Compile / scalaSource := baseDirectory.value / "src" / "main"

src/main/LevelSpace.scala

@@ -1,10 +1,8 @@
 package org.nlogo.ls
 
-import java.awt.GraphicsEnvironment
 import java.awt.event.{ ActionEvent, ActionListener }
 import java.lang.{ Double => JDouble }
 import java.util
-import java.util.Objects
 import java.util.concurrent.ConcurrentHashMap
 import javax.swing.JMenuItem
 
@@ -14,15 +12,13 @@ import org.nlogo.app.{ App, ToolsMenu }
 import org.nlogo.awt.EventQueue
 import org.nlogo.core.LogoList
 import org.nlogo.nvm.HaltException
-import org.nlogo.workspace.{ AbstractWorkspace, ExtensionManager => WorkspaceExtensionManager }
+import org.nlogo.workspace.AbstractWorkspace
 
 import scala.collection.immutable.ArraySeq
 import scala.jdk.CollectionConverters.ConcurrentMapHasAsScala
 
 object LevelSpace {
-  private var isHeadlessWorkspace = false
-  def isHeadless: Boolean =
-    isHeadlessWorkspace || GraphicsEnvironment.isHeadless || Objects.equals(System.getProperty("org.nlogo.preferHeadless"), "true")
+  var isHeadless = true
 
   @throws[ExtensionException]
   def castToId(id: Any): Int = id match {
@@ -207,14 +203,7 @@ class LevelSpace extends DefaultClassManager { // This can be accessed by both t
 
   @throws[ExtensionException]
   override def runOnce(em: ExtensionManager): Unit = {
-    // "Can't we just check the `org.nlogo.preferHeadless` property?"  Well, kind-of, but
-    // it turns out that doesn't get set automatically and there are a lot of ways to run
-    // NetLogo models headlessly that "forget" to do it.  It's safer to check if the
-    // workspace we're using is headless in addition to checking the property.  -Jeremy B
-    // July 2022
-    LevelSpace.isHeadlessWorkspace = em.isInstanceOf[WorkspaceExtensionManager] &&
-      em.asInstanceOf[WorkspaceExtensionManager].workspace.isInstanceOf[AbstractWorkspace] &&
-      em.asInstanceOf[WorkspaceExtensionManager].workspace.asInstanceOf[AbstractWorkspace].isHeadless
+    LevelSpace.isHeadless = !em.workspaceContext.workspaceGUI
 
     if (!LevelSpace.isHeadless) {
       modelManager = new BackingModelManager

src/test/Test.scala

@@ -1,7 +1,7 @@
 package org.nlogo.ls
 
+import java.io.File
+
 import org.nlogo.headless.TestLanguage
 
-class Tests extends TestLanguage(Seq(new java.io.File("tests.txt").getCanonicalFile)) {
-  System.setProperty("org.nlogo.preferHeadless", "true")
-}
+class Tests extends TestLanguage(Seq(new File("tests.txt").getCanonicalFile))

tests.txt

@@ -98,8 +98,8 @@ ls-set-name
 ls-path-of
   extensions [ ls ]
   O> ls:create-models 1 "extensions/ls/test/Blank.nlogox"
-  member? "extensions/ls/test/Blank.nlogox" ls:path-of 0 => true
-  member? "extensions/ls/test/Blank.nlogox" first ls:path-of [0] => true
+  member? "extensions/ls/test/Blank.nlogox" ls:path-of 0 or member? "extensions\\ls\\test\\Blank.nlogox" ls:path-of 0 => true
+  member? "extensions/ls/test/Blank.nlogox" first ls:path-of [0] or member? "extensions\\ls\\test\\Blank.nlogox" first ls:path-of [0] => true
 
 *ls-errors-propagate
   extensions [ ls ]