Fix NPE when Find action is unavailable in Breakpoints view

[mx990]

The Find action may be unavailable when the focus is outside the Breakpoints view, which leads to an NPE in fillContextMenu.

This adds a null and enablement check for the Find action to resolve the problem.

Fixes #2558

[github-actions]

Test Results

 1 980 files  +1 926   1 980 suites  +1 926   1h 32m 8s ⏱️ + 57m 19s
 4 750 tests +  204   4 726 ✅ +  203   24 💤 + 1  0 ❌ ±0 
14 250 runs  +2 016  14 068 ✅ +1 993  182 💤 +23  0 ❌ ±0 

Results for commit 4a502e1. ± Comparison against base commit fce9709.

This pull request removes 4543 and adds 4747 tests. Note that renamed tests count towards both.

org.eclipse.ant.tests.core.tests.FrameworkTests ‑ testAntClasspathEntryFromUrl
org.eclipse.ant.tests.core.tests.FrameworkTests ‑ testClasspathOrdering
org.eclipse.ant.tests.core.tests.FrameworkTests ‑ testClasspathOrderingDeprecated
org.eclipse.ant.tests.core.tests.FrameworkTests ‑ testGetTargets
org.eclipse.ant.tests.core.tests.FrameworkTests ‑ testGlobalProperty
org.eclipse.ant.tests.core.tests.FrameworkTests ‑ testGlobalPropertyFile
org.eclipse.ant.tests.core.tests.FrameworkTests ‑ testGlobalPropertyFileWithMinusDTakingPrecedence
org.eclipse.ant.tests.core.tests.FrameworkTests ‑ testIncludeAntRuntime
org.eclipse.ant.tests.core.tests.FrameworkTests ‑ testNoDefaultTarget
org.eclipse.ant.tests.core.tests.FrameworkTests ‑ testSettingAntHome
…

AllCompareTests AsyncExecTests ‑ testCancelOnRequeue
AllCompareTests AsyncExecTests ‑ testQueueAdd
AllCompareTests AsyncExecTests ‑ testWorker
AllCompareTests CompareFileRevisionEditorInputTest ‑ testPrepareCompareInputWithNonLocalResourceTypedElements
AllCompareTests CompareUIPluginTest ‑ testFindContentViewerDescriptorForTextType_StreamAccessor
AllCompareTests CompareUIPluginTest ‑ testFindContentViewerDescriptor_TextType_NotStreamAccessor
AllCompareTests CompareUIPluginTest ‑ testFindContentViewerDescriptor_UnknownType
AllCompareTests ContentMergeViewerTest ‑ testFFFX
AllCompareTests ContentMergeViewerTest ‑ testFFTX
AllCompareTests ContentMergeViewerTest ‑ testFFXF
…

This pull request removes 23 skipped tests and adds 24 skipped tests. Note that renamed tests count towards both.

org.eclipse.core.internal.expressions.tests.ExpressionTests ‑ testSubTypeTiming
org.eclipse.core.tests.internal.builders.BuilderCycleTest ‑ testNeedRebuild
org.eclipse.core.tests.internal.preferences.EclipsePreferencesTest ‑ _testRemoveDeletesFile
org.eclipse.core.tests.internal.preferences.PreferencesServiceTest ‑ testApplyWithTransfers
org.eclipse.core.tests.resources.CharsetTest ‑ testBug67606
org.eclipse.core.tests.resources.CharsetTest ‑ testCopyFileCopiesCharset
org.eclipse.core.tests.resources.LinkedResourceSyncMoveAndCopyTest ‑ testCopyFolderWithLinksToNonExistingLocations_withShallow
org.eclipse.core.tests.resources.ResourceAttributeTest ‑ testRefreshExecutableOnFolder
org.eclipse.core.tests.resources.refresh.RefreshJobTest ‑ testBigRecursionDeepRefresh
org.eclipse.core.tests.resources.refresh.RefreshJobTest ‑ testSmallRecursionRefresh
…

AllExpressionTests ExpressionTests ‑ testSubTypeTiming
AllTipsTests TipTest ‑ testGetImage
AutomatedResourceTests AllBuilderTests BuilderCycleTest ‑ testNeedRebuild
AutomatedResourceTests AllRefreshTests RefreshJobTest ‑ testBigRecursionDeepRefresh
AutomatedResourceTests AllRefreshTests RefreshJobTest ‑ testSmallRecursionRefresh
AutomatedResourceTests AllRefreshTests RefreshJobTest ‑ testUnrelatedRule(TestInfo)
AutomatedResourceTests AllRegressionTests Bug_032076 ‑ testFileBugOnLinux
AutomatedResourceTests AllRegressionTests Bug_032076 ‑ testFolderBugOnLinux
AutomatedResourceTests AllRegressionTests Bug_032076 ‑ testProjectBugOnLinux(Path)
AutomatedResourceTests AllRegressionTests Bug_079398 ‑ testBug79398
…

[elsazac]

LGTM

[elsazac]

Merging this now;

[fedejeanne]

Hi @mx990, thank you for the fix!

Question: there are other usages of the method getAction(...) and also other calls with the exact same parameter here:

Do you know if those are safe?

[mx990]

Hi @fedejeanne, thank you for pointing me to those other locations!

I was able to produce a similar exception in the Expressions view:

java.lang.NullPointerException: Cannot invoke "org.eclipse.jface.action.IAction.setImageDescriptor(org.eclipse.jface.resource.ImageDescriptor)" because "action" is null
	at org.eclipse.debug.internal.ui.views.expression.ExpressionView.fillContextMenu(ExpressionView.java:87)
	at org.eclipse.jface.action.MenuManager.fireAboutToShow(MenuManager.java:337)

I was also able to produce an error in the Variables view, which does have a null check but logs an exception:

java.lang.IllegalStateException: No action found for id: find, fGlobalActionMap: {selectAll=null, find=org.eclipse.debug.internal.ui.viewers.model.VirtualFindAction@5cca5ff3, copy=org.eclipse.ui.internal.ViewPluginAction@2fcad739, paste=null}
	at org.eclipse.debug.internal.ui.views.variables.VariablesView.fillContextMenu(VariablesView.java:1109)
	at org.eclipse.jface.action.MenuManager.fireAboutToShow(MenuManager.java:337)

I was unable to produce an exception or error in either the Modules or Launch view, but it may still be sensible to also add corresponding null checks there.

[mx990]

I have created an additional PR #2562 to fix the NPE in the Expressions view. Please let me know if I should also change the other locations.

[fedejeanne]

Great, thank you for looking into it! No need to change the one in the Variables View on my account. @iloveeclipse since you made that change back then (e583bf6) WDYT?