Variables button in arguments tab of run configurations throws an NPE when trying to add a dynamic variable for working directory

[Sai-krishna91]

Describe the bug
The variables button for working directory in the arguments tab of run configurations dialog doesn't work. After selecting a dynamic variable from the variables dialog, the text field for working directory is not updated.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'Run configurations' dialog
2. Create a launch config for 'C/C++ Application'
3. Select the arguments tab
4. Uncheck 'Use default' for working directory.
5. Click on 'Variables' button against the working directory field
6. From the Variables dialog, select any dynamic variable
7. The working directory text box is not updated

Expected behavior
The working directory text field should be updated with the selected dynamic variable

Screenshots

Desktop (please complete the following information):

• OS: Windows 10
• Browser: Google chrome
• Version: 114.0.5735.199

Additional context

[From the log]

!ENTRY org.eclipse.ui 4 0 2023-07-14 19:46:39.407
!MESSAGE Unhandled event loop exception
!STACK 0
java.lang.NullPointerException: Cannot invoke "org.eclipse.swt.widgets.Text.insert(String)" because "textField" is null
	at org.eclipse.cdt.launch.ui.CLaunchConfigurationTab.handleVariablesButtonSelected(CLaunchConfigurationTab.java:200)
	at org.eclipse.cdt.launch.ui.CLaunchConfigurationTab$1.widgetSelected(CLaunchConfigurationTab.java:186)
	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:4274)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1066)
	at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4072)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3660)
	at org.eclipse.jface.window.Window.runEventLoop(Window.java:823)
	at org.eclipse.jface.window.Window.open(Window.java:799)
	at org.eclipse.debug.internal.ui.launchConfigurations.LaunchConfigurationsDialog.open(LaunchConfigurationsDialog.java:1238)
	at org.eclipse.debug.ui.DebugUITools.lambda$1(DebugUITools.java:630)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:67)
	at org.eclipse.debug.ui.DebugUITools.openLaunchConfigurationDialogOnGroup(DebugUITools.java:636)
	at org.eclipse.debug.ui.DebugUITools.openLaunchConfigurationDialogOnGroup(DebugUITools.java:574)
	at org.eclipse.debug.ui.actions.OpenLaunchDialogAction.run(OpenLaunchDialogAction.java:85)
	at org.eclipse.jface.action.Action.runWithEvent(Action.java:474)
	at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:580)
	at org.eclipse.jface.action.ActionContributionItem.lambda$4(ActionContributionItem.java:414)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:89)
	at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4274)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1066)
	at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4072)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3660)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1155)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:338)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1046)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:155)
	at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:643)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:338)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:550)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:171)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:152)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:203)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:136)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:402)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:255)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:568)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:659)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:596)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1467)

!ENTRY org.eclipse.ui 4 0 2023-07-14 19:46:50.947
!MESSAGE Unhandled event loop exception
!STACK 0
java.lang.NullPointerException: Cannot invoke "org.eclipse.swt.widgets.Text.insert(String)" because "textField" is null
	at org.eclipse.cdt.launch.ui.CLaunchConfigurationTab.handleVariablesButtonSelected(CLaunchConfigurationTab.java:200)
	at org.eclipse.cdt.launch.ui.CLaunchConfigurationTab$1.widgetSelected(CLaunchConfigurationTab.java:186)
	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:4274)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1066)
	at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4072)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3660)
	at org.eclipse.jface.window.Window.runEventLoop(Window.java:823)
	at org.eclipse.jface.window.Window.open(Window.java:799)
	at org.eclipse.debug.internal.ui.launchConfigurations.LaunchConfigurationsDialog.open(LaunchConfigurationsDialog.java:1238)
	at org.eclipse.debug.ui.DebugUITools.lambda$1(DebugUITools.java:630)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:67)
	at org.eclipse.debug.ui.DebugUITools.openLaunchConfigurationDialogOnGroup(DebugUITools.java:636)
	at org.eclipse.debug.ui.DebugUITools.openLaunchConfigurationDialogOnGroup(DebugUITools.java:574)
	at org.eclipse.debug.ui.actions.OpenLaunchDialogAction.run(OpenLaunchDialogAction.java:85)
	at org.eclipse.jface.action.Action.runWithEvent(Action.java:474)
	at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:580)
	at org.eclipse.jface.action.ActionContributionItem.lambda$4(ActionContributionItem.java:414)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:89)
	at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4274)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1066)
	at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4072)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3660)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1155)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:338)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1046)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:155)
	at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:643)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:338)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:550)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:171)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:152)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:203)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:136)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:402)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:255)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:568)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:659)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:596)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1467)

[jonahgraham]

This has been broken for a very long time :-( - it regressed in commit 4a793c0 13 years ago. The fix is trivial and a PR is coming soon.

[jonahgraham]

Thanks @Sai-krishna91 for taking the time to report this issue. The next release should have a fix for this available. In the meantime I will have to trouble you to workaround the issue.

[Sai-krishna91]

Thanks @jonahgraham. As a workaround I can simply type in the dynamic variable. That is working. I will verify the fix in the next release. Is it okay to close this as you have checked in the fix?