In a new language project created with the wizard, create an empty file, open it, write something then delete everything and editor crashes:

org.eclipse.swt.SWTException: Failed to execute runnable (java.lang.NullPointerException)
	at org.eclipse.swt.SWT.error(SWT.java:4441)
	at org.eclipse.swt.SWT.error(SWT.java:4356)
	at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:139)
	at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3994)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3671)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$9.run(PartRenderingEngine.java:1151)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1032)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:148)
	at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:636)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:579)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:135)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:380)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:235)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:497)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:648)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:603)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1465)
Caused by: java.lang.NullPointerException
	at org.eclipse.jface.text.source.AnnotationPainter.applyTextPresentation(AnnotationPainter.java:1022)
	at org.eclipse.jface.text.TextViewer.changeTextPresentation(TextViewer.java:4920)
	at org.metaborg.spoofax.eclipse.editor.SpoofaxEditor$3.run(SpoofaxEditor.java:245)
	at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
	at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:136)
	... 23 more

Eclipse: org.eclipse.epp.package.standard.feature.feature.group 4.4.2.20150219-0708
Spoofax: org.metaborg.spoofax.eclipse 1.5.0.20151022-100640-new-spoofax-plugin
System: Mac OS X x86_64 10.11.1

Submitted by Vlad Vergu on 22 October 2015 at 11:29

Probably a related error is this, which happens when trying to insert a line at line 0 pushing the existent content down:

org.eclipse.swt.SWTException: Failed to execute runnable (java.lang.IllegalArgumentException: Argument not valid)
	at org.eclipse.swt.SWT.error(SWT.java:4441)
	at org.eclipse.swt.SWT.error(SWT.java:4356)
	at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:139)
	at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3994)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3671)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$9.run(PartRenderingEngine.java:1151)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1032)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:148)
	at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:636)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:579)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:135)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:380)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:235)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:497)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:648)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:603)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1465)
Caused by: java.lang.IllegalArgumentException: Argument not valid
	at org.eclipse.swt.SWT.error(SWT.java:4422)
	at org.eclipse.swt.SWT.error(SWT.java:4356)
	at org.eclipse.swt.SWT.error(SWT.java:4327)
	at org.eclipse.swt.custom.StyledText.setStyleRanges(StyledText.java:9819)
	at org.eclipse.swt.custom.StyledText.setStyleRange(StyledText.java:9701)
	at org.eclipse.jface.text.TextViewer.addPresentation(TextViewer.java:4823)
	at org.eclipse.jface.text.TextViewer.changeTextPresentation(TextViewer.java:4933)
	at org.metaborg.spoofax.eclipse.editor.SpoofaxEditor$3.run(SpoofaxEditor.java:245)
	at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
	at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:136)
	... 23 more

Probably related to https://yellowgrass.org/issue/SpoofaxWithCore/11

The same happens when simply trying to type at 0:0

@Gohla probably.

Fixed