Quickfix for disallowed keyword 'var' does not work

[jthoene]

The quickfix for the disallowed keyword 'var', which should replace the Variable Definition. Throws the following exception:

org.eclipse.emf.common.util.WrappedException: java.lang.IllegalStateException
	at org.eclipse.xtext.ui.editor.quickfix.IssueResolution.apply(IssueResolution.java:78)
	at org.eclipse.xtext.ui.editor.quickfix.QuickAssistCompletionProposal.apply(QuickAssistCompletionProposal.java:36)
	at org.eclipse.xtext.ui.editor.hover.AnnotationWithQuickFixesHover$AnnotationInformationControl.apply(AnnotationWithQuickFixesHover.java:536)
	at org.eclipse.xtext.ui.editor.hover.AnnotationWithQuickFixesHover$AnnotationInformationControl.access$2(AnnotationWithQuickFixesHover.java:513)
	at org.eclipse.xtext.ui.editor.hover.AnnotationWithQuickFixesHover$AnnotationInformationControl$5.widgetSelected(AnnotationWithQuickFixesHover.java:507)
	at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:252)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:89)
	at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4131)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1056)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1080)
	at org.eclipse.swt.widgets.Widget.sendSelectionEvent(Widget.java:1097)
	at org.eclipse.swt.widgets.Link.wmNotifyChild(Link.java:696)
	at org.eclipse.swt.widgets.Control.wmNotify(Control.java:5785)
	at org.eclipse.swt.widgets.Composite.wmNotify(Composite.java:1988)
	at org.eclipse.swt.widgets.Control.WM_NOTIFY(Control.java:5351)
	at org.eclipse.swt.widgets.Control.windowProc(Control.java:4815)
	at org.eclipse.swt.widgets.Display.windowProc(Display.java:4778)
	at org.eclipse.swt.internal.win32.OS.CallWindowProc(Native Method)
	at org.eclipse.swt.widgets.Link.callWindowProc(Link.java:160)
	at org.eclipse.swt.widgets.Widget.wmLButtonUp(Widget.java:1933)
	at org.eclipse.swt.widgets.Control.WM_LBUTTONUP(Control.java:5164)
	at org.eclipse.swt.widgets.Control.windowProc(Control.java:4796)
	at org.eclipse.swt.widgets.Display.windowProc(Display.java:4770)
	at org.eclipse.swt.internal.win32.OS.DispatchMessage(Native Method)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3545)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1173)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:338)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1062)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:155)
	at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:635)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:338)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:559)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:155)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:203)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:137)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:107)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:400)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:255)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:660)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:597)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1468)
	at org.eclipse.equinox.launcher.Main.main(Main.java:1441)
Caused by: java.lang.IllegalStateException
	at org.eclipse.xtext.serializer.sequencer.AbstractSyntacticSequencer.enterAssignedParserRuleCall(AbstractSyntacticSequencer.java:353)
	at org.eclipse.xtext.serializer.acceptor.SequenceFeeder.acceptEObjectRuleCall(SequenceFeeder.java:324)
	at org.eclipse.xtext.serializer.acceptor.SequenceFeeder.acceptRuleCall(SequenceFeeder.java:353)
	at org.eclipse.xtext.serializer.acceptor.SequenceFeeder.accept(SequenceFeeder.java:247)
	at org.eclipse.xtext.serializer.sequencer.BacktrackingSemanticSequencer.accept(BacktrackingSemanticSequencer.java:451)
	at org.eclipse.xtext.serializer.sequencer.BacktrackingSemanticSequencer.createSequence(BacktrackingSemanticSequencer.java:511)
	at com.yakindu.solidity.serializer.SoliditySemanticSequencer.sequence_VariableDefinition(SoliditySemanticSequencer.java:2016)
	at com.yakindu.solidity.serializer.SoliditySemanticSequencer.sequence(SoliditySemanticSequencer.java:337)
	at org.eclipse.xtext.serializer.sequencer.AbstractSemanticSequencer.createSequence(AbstractSemanticSequencer.java:67)
	at org.eclipse.xtext.serializer.acceptor.SequenceFeeder.acceptEObjectRuleCall(SequenceFeeder.java:326)
	at org.eclipse.xtext.serializer.acceptor.SequenceFeeder.acceptRuleCall(SequenceFeeder.java:353)
	at org.eclipse.xtext.serializer.acceptor.SequenceFeeder.accept(SequenceFeeder.java:264)
	at org.eclipse.xtext.serializer.sequencer.BacktrackingSemanticSequencer.accept(BacktrackingSemanticSequencer.java:444)
	at org.eclipse.xtext.serializer.sequencer.BacktrackingSemanticSequencer.createSequence(BacktrackingSemanticSequencer.java:511)
	at com.yakindu.solidity.serializer.SoliditySemanticSequencer.sequence_Block(SoliditySemanticSequencer.java:598)
	at com.yakindu.solidity.serializer.SoliditySemanticSequencer.sequence(SoliditySemanticSequencer.java:189)
	at org.eclipse.xtext.serializer.sequencer.AbstractSemanticSequencer.createSequence(AbstractSemanticSequencer.java:67)
	at org.eclipse.xtext.serializer.impl.Serializer.serialize(Serializer.java:118)
	at org.eclipse.xtext.serializer.impl.Serializer.serializeToRegions(Serializer.java:140)
	at org.eclipse.xtext.serializer.impl.Serializer.serialize(Serializer.java:146)
	at org.eclipse.xtext.serializer.impl.Serializer.serialize(Serializer.java:180)
	at org.eclipse.xtext.serializer.impl.Serializer.serializeReplacement(Serializer.java:211)
	at org.eclipse.xtext.ui.editor.model.edit.DefaultTextEditComposer.getObjectEdits(DefaultTextEditComposer.java:176)
	at org.eclipse.xtext.ui.editor.model.edit.DefaultTextEditComposer.getTextEdit(DefaultTextEditComposer.java:146)
	at org.eclipse.xtext.ui.editor.model.edit.DefaultTextEditComposer.endRecording(DefaultTextEditComposer.java:129)
	at org.eclipse.xtext.ui.editor.model.edit.ReconcilingUnitOfWork.exec(ReconcilingUnitOfWork.java:57)
	at org.eclipse.xtext.ui.editor.model.edit.ReconcilingUnitOfWork.exec(ReconcilingUnitOfWork.java:1)
	at org.eclipse.xtext.resource.OutdatedStateManager.exec(OutdatedStateManager.java:91)
	at org.eclipse.xtext.ui.editor.model.XtextDocument$XtextDocumentLocker.modify(XtextDocument.java:434)
	at org.eclipse.xtext.ui.editor.model.XtextDocument.internalModify(XtextDocument.java:167)
	at org.eclipse.xtext.ui.editor.model.XtextDocument.modify(XtextDocument.java:160)
	at org.eclipse.xtext.ui.editor.model.edit.SemanticModificationWrapper.apply(SemanticModificationWrapper.java:32)
	at org.eclipse.xtext.ui.editor.quickfix.IssueResolution.apply(IssueResolution.java:76)
	... 46 more

After some further investigation by me, it seems like the Sequencer does not accept the typeSpecifier set by the quickfix for the replacing VariableDefinition.

Solidity example code to reproduce the problem:

pragma solidity ^0.5.9;
			
contract Test {
    function return0() pure public returns (bool)
    {
        var x = true;
        return x;
    }
}