Eclipse: org.eclipse.epp.package.standard.feature.feature.group 4.4.2.20150219-0708
Spoofax: org.metaborg.spoofax.eclipse 1.5.0.20150422-172149
System: Linux amd64 3.16.0-34-generic

If I have a valid program (not an empty text file) and I try to insert a character at the beginning of the file, then most of the times it throws the following exception and the editor will hang:

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:3774)
        at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3412)
        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)
        at org.eclipse.equinox.launcher.Main.main(Main.java:1438)
    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.EditorUpdateJob$2.run(EditorUpdateJob.java:214)
        at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
        at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:136)
        ... 24 more

Submitted by Oskar van Rest on 23 April 2015 at 16:58

This happens when inserting, for example, a new line or a space (i.e. the resulting program is still valid) or when inserting a random symbol (i.e. the resulting program is invalid).

Fixed