JS. `NoSuchElementException` is thrown in IDE when there are no functions in the JS-file

[alisevych]

Description

NoSuchElementException is thrown from GenerateTestsAction when there are no functions in the file

To Reproduce

1. Install the latest IU plugin built from unit-test-bot/rc3102023 branch in IntelliJ Idea Ultimate 2022.2.4 - take utbot-intellij-IU-2023.3.* artefact
2. Create a JavaScript project with sample code
3. Call Alt+Shift+U on hello.js

Expected behavior

UnitTestBot action should be not available for a file without functions.

Actual behavior

Two similar exceptions are thrown from rg.utbot.intellij.plugin.language.js.JsLanguageAssistant.getPsiTargets
java.util.NoSuchElementException: List is empty.

1. for GenerateTestsAction#update@keyboard shortcut
2. for GenerateTestsAction#update@ProjectViewPopup

Visual proofs (screenshots, logs, images)

GenerateTestsAction#update@keyboard shortcut (org.utbot.intellij.plugin.ui.actions.GenerateTestsAction), actionId=org.utbot.intellij.plugin.ui.actions.GenerateTestsAction, text='Generate Tests with UnitTestBot...'

java.util.NoSuchElementException: List is empty.
	at kotlin.collections.CollectionsKt___CollectionsKt.first(_Collections.kt:214)
	at org.utbot.intellij.plugin.language.js.JsLanguageAssistant.getPsiTargets(JsLanguageAssistant.kt:91)
	at org.utbot.intellij.plugin.language.js.JsLanguageAssistant.update(JsLanguageAssistant.kt:51)
	at org.utbot.intellij.plugin.ui.actions.GenerateTestsAction.update(GenerateTestsAction.kt:19)
	at com.intellij.openapi.actionSystem.ex.ActionUtil.lambda$performDumbAwareUpdate$0(ActionUtil.java:150)
	at com.intellij.openapi.actionSystem.ex.ActionUtil.performDumbAwareUpdate(ActionUtil.java:173)
	at com.intellij.openapi.actionSystem.impl.ActionUpdater.doUpdate(ActionUpdater.java:660)
	at com.intellij.openapi.actionSystem.impl.ActionUpdater.lambda$updateActionReal$4(ActionUpdater.java:128)
	at com.intellij.openapi.actionSystem.impl.ActionUpdater.lambda$computeOnEdt$6(ActionUpdater.java:211)
	at com.intellij.openapi.progress.ProgressManager.lambda$runProcess$0(ProgressManager.java:66)
	at com.intellij.openapi.progress.impl.CoreProgressManager.lambda$runProcess$2(CoreProgressManager.java:188)
	at com.intellij.openapi.progress.impl.CoreProgressManager.lambda$executeProcessUnderProgress$12(CoreProgressManager.java:608)
	at com.intellij.openapi.progress.impl.CoreProgressManager.registerIndicatorAndRun(CoreProgressManager.java:683)
	at com.intellij.openapi.progress.impl.CoreProgressManager.computeUnderProgress(CoreProgressManager.java:639)
	at com.intellij.openapi.progress.impl.CoreProgressManager.executeProcessUnderProgress(CoreProgressManager.java:607)
	at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:60)
	at com.intellij.openapi.progress.impl.CoreProgressManager.runProcess(CoreProgressManager.java:175)
	at com.intellij.openapi.progress.ProgressManager.runProcess(ProgressManager.java:66)
	at com.intellij.openapi.actionSystem.impl.ActionUpdater.lambda$computeOnEdt$7(ActionUpdater.java:207)
	at com.intellij.openapi.actionSystem.impl.ActionUpdateEdtExecutor.lambda$computeOnEdt$0(ActionUpdateEdtExecutor.java:45)
	at com.intellij.openapi.actionSystem.impl.Utils.lambda$runUpdateSessionForInputEvent$25(Utils.java:725)
	at com.intellij.openapi.actionSystem.impl.Utils.runLoopAndWaitForFuture(Utils.java:778)
	at com.intellij.openapi.actionSystem.impl.Utils.runUpdateSessionForInputEvent(Utils.java:723)
	at com.intellij.openapi.keymap.impl.IdeKeyEventDispatcher.lambda$processAction$4(IdeKeyEventDispatcher.java:629)
	at com.intellij.openapi.progress.ProgressManager.lambda$runProcess$0(ProgressManager.java:66)
	at com.intellij.openapi.progress.impl.CoreProgressManager.lambda$runProcess$2(CoreProgressManager.java:188)
	at com.intellij.openapi.progress.impl.CoreProgressManager.lambda$executeProcessUnderProgress$12(CoreProgressManager.java:608)
	at com.intellij.openapi.progress.impl.CoreProgressManager.registerIndicatorAndRun(CoreProgressManager.java:683)
	at com.intellij.openapi.progress.impl.CoreProgressManager.computeUnderProgress(CoreProgressManager.java:639)
	at com.intellij.openapi.progress.impl.CoreProgressManager.executeProcessUnderProgress(CoreProgressManager.java:607)
	at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:60)
	at com.intellij.openapi.progress.impl.CoreProgressManager.runProcess(CoreProgressManager.java:175)
	at com.intellij.openapi.progress.ProgressManager.runProcess(ProgressManager.java:66)
	at com.intellij.openapi.keymap.impl.IdeKeyEventDispatcher.processAction(IdeKeyEventDispatcher.java:627)
	at com.intellij.openapi.keymap.impl.IdeKeyEventDispatcher.processAction(IdeKeyEventDispatcher.java:606)
	at com.intellij.openapi.keymap.impl.IdeKeyEventDispatcher.processActionOrWaitSecondStroke(IdeKeyEventDispatcher.java:489)
	at com.intellij.openapi.keymap.impl.IdeKeyEventDispatcher.inInitState(IdeKeyEventDispatcher.java:478)
	at com.intellij.openapi.keymap.impl.IdeKeyEventDispatcher.dispatchKeyEvent(IdeKeyEventDispatcher.java:229)
	at com.intellij.ide.IdeEventQueue.dispatchKeyEvent(IdeEventQueue.java:824)
	at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.java:760)
	at com.intellij.ide.IdeEventQueue.lambda$dispatchEvent$6(IdeEventQueue.java:450)
	at com.intellij.openapi.progress.impl.CoreProgressManager.computePrioritized(CoreProgressManager.java:791)
	at com.intellij.ide.IdeEventQueue.lambda$dispatchEvent$7(IdeEventQueue.java:449)
	at com.intellij.openapi.application.TransactionGuardImpl.performActivity(TransactionGuardImpl.java:113)
	at com.intellij.ide.IdeEventQueue.performActivity(IdeEventQueue.java:624)
	at com.intellij.ide.IdeEventQueue.lambda$dispatchEvent$8(IdeEventQueue.java:447)
	at com.intellij.openapi.application.impl.ApplicationImpl.runIntendedWriteActionOnCurrentThread(ApplicationImpl.java:881)
	at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:493)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:207)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
	at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:92)

Environment

Seems to be environment independent.
Used: Windows 10 Pro, Node.js 18.14.2