Description andrew 2005-04-06 05:03:20 EDT

Content assist fails when there is a string token beginning with an
escape sequence *below* the content assist point.

Given the following class:

class Test {
  void foo() {
    // content assist here fails
  }

  String X = "\n";

  void bar() {
    // content assist here succeeds
  }
}

When triggering content assist inside foo() with Ctrl+Space, Eclipse displays
the "Error Executing Command" popup ("The command for the key you pressed
failed"). The stack trace from .log is shown at the end of this report. Doing
the same inside bar() produces the expected selection box. 

Note that:
 - Moving the declaration of X above foo() in the file makes it succeed in both
   places.
 - Moving the declaration of X below bar() in the file makes it fail in both
   places.
 - Adding more escape sequences to X (e.g. "\n\n") makes it succeed regardless
   of location.
 - Changing the first character of X to something other than an escape sequence
   (e.g. "x\n") makes it succeed regardless of location.
 - Adding more characters after the escape sequence (other than more escapes,
   e.g. "\nabc") has no effect.
 - Changing the context in which the string token is used (e.g. Integer X =
   Integer.parseInt("\n");) has no effect.
 - Changing the scope of X such that foo() can't see it (e.g. putting it inside
   a static block, or inside bar()) makes it succeed regardless of location.

Platform(s):
 - Eclipse 3.1M6
 - Java 1.4.2_03-b02
 - Windows XP Pro SP2 and Solaris 8 (Motif)

I checked the same case in 3.1M5a on both platforms, and neither produced this
behaviour.

Stack Trace from .log:
!ENTRY org.eclipse.ui 4 4 2005-04-06 18:39:52.968
!MESSAGE The command for the key you pressed failed

!ENTRY org.eclipse.ui 4 0 2005-04-06 18:39:52.968
!MESSAGE The command for the key you pressed failed
!STACK 0
java.lang.NegativeArraySizeException
	at
org.eclipse.jdt.internal.compiler.parser.Scanner.getCurrentTokenSourceString(Scanner.java:501)
	at org.eclipse.jdt.internal.compiler.parser.Parser.consumeToken(Parser.java:6793)
	at
org.eclipse.jdt.internal.codeassist.impl.AssistParser.consumeToken(AssistParser.java:666)
	at
org.eclipse.jdt.internal.codeassist.complete.CompletionParser.consumeToken(CompletionParser.java:2235)
	at org.eclipse.jdt.internal.compiler.parser.Parser.parse(Parser.java:8377)
	at org.eclipse.jdt.internal.compiler.parser.Parser.parse(Parser.java:8560)
	at org.eclipse.jdt.internal.compiler.parser.Parser.parse(Parser.java:8525)
	at org.eclipse.jdt.internal.compiler.parser.Parser.dietParse(Parser.java:7343)
	at
org.eclipse.jdt.internal.codeassist.complete.CompletionParser.dietParse(CompletionParser.java:2905)
	at
org.eclipse.jdt.internal.codeassist.CompletionEngine.complete(CompletionEngine.java:1057)
	at org.eclipse.jdt.internal.core.Openable.codeComplete(Openable.java:119)
	at
org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:300)
	at
org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:293)
	at
org.eclipse.jdt.internal.ui.text.java.JavaCompletionProcessor.internalComputeCompletionProposals(JavaCompletionProcessor.java:335)
	at
org.eclipse.jdt.internal.ui.text.java.JavaCompletionProcessor.computeCompletionProposals(JavaCompletionProcessor.java:313)
	at
org.eclipse.jface.text.contentassist.ContentAssistant.computeCompletionProposals(ContentAssistant.java:1470)
	at
org.eclipse.jface.text.contentassist.CompletionProposalPopup.computeProposals(CompletionProposalPopup.java:250)
	at
org.eclipse.jface.text.contentassist.CompletionProposalPopup.access$7(CompletionProposalPopup.java:247)
	at
org.eclipse.jface.text.contentassist.CompletionProposalPopup$1.run(CompletionProposalPopup.java:206)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:69)
	at
org.eclipse.jface.text.contentassist.CompletionProposalPopup.showProposals(CompletionProposalPopup.java:201)
	at
org.eclipse.jface.text.contentassist.ContentAssistant.showPossibleCompletions(ContentAssistant.java:1319)
	at
org.eclipse.jdt.internal.ui.javaeditor.CompilationUnitEditor$AdaptedSourceViewer.doOperation(CompilationUnitEditor.java:183)
	at org.eclipse.ui.texteditor.ContentAssistAction$1.run(ContentAssistAction.java:82)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:69)
	at org.eclipse.ui.texteditor.ContentAssistAction.run(ContentAssistAction.java:80)
	at org.eclipse.jface.action.Action.runWithEvent(Action.java:996)
	at org.eclipse.ui.commands.ActionHandler.execute(ActionHandler.java:182)
	at
org.eclipse.ui.internal.handlers.LegacyHandlerWrapper.execute(LegacyHandlerWrapper.java:108)
	at org.eclipse.core.commands.Command.execute(Command.java:331)
	at
org.eclipse.core.commands.ParameterizedCommand.execute(ParameterizedCommand.java:396)
	at
org.eclipse.ui.internal.keys.WorkbenchKeyboard.executeCommand(WorkbenchKeyboard.java:452)
	at org.eclipse.ui.internal.keys.WorkbenchKeyboard.press(WorkbenchKeyboard.java:741)
	at
org.eclipse.ui.internal.keys.WorkbenchKeyboard.processKeyEvent(WorkbenchKeyboard.java:784)
	at
org.eclipse.ui.internal.keys.WorkbenchKeyboard.filterKeySequenceBindings(WorkbenchKeyboard.java:543)
	at
org.eclipse.ui.internal.keys.WorkbenchKeyboard.access$3(WorkbenchKeyboard.java:486)
	at
org.eclipse.ui.internal.keys.WorkbenchKeyboard$KeyDownFilter.handleEvent(WorkbenchKeyboard.java:110)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:82)
	at org.eclipse.swt.widgets.Display.filterEvent(Display.java:777)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:841)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:866)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:851)
	at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:879)
	at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:875)
	at org.eclipse.swt.widgets.Widget.wmChar(Widget.java:1182)
	at org.eclipse.swt.widgets.Control.WM_CHAR(Control.java:3126)
	at org.eclipse.swt.widgets.Control.windowProc(Control.java:3029)
	at org.eclipse.swt.widgets.Display.windowProc(Display.java:3466)
	at org.eclipse.swt.internal.win32.OS.DispatchMessageW(Native Method)
	at org.eclipse.swt.internal.win32.OS.DispatchMessage(OS.java:1625)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:2525)
	at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:1570)
	at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:1534)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:306)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:143)
	at org.eclipse.ui.internal.ide.IDEApplication.run(IDEApplication.java:103)
	at
org.eclipse.core.internal.runtime.PlatformActivator$1.run(PlatformActivator.java:228)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:344)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:156)
	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.core.launcher.Main.invokeFramework(Main.java:315)
	at org.eclipse.core.launcher.Main.basicRun(Main.java:268)
	at org.eclipse.core.launcher.Main.run(Main.java:942)
	at org.eclipse.core.launcher.Main.main(Main.java:926)