Fix Enter action will add incorrect number of newlines when triggered inside braces

.changes/next-release/bugfix-f4efde0c-8cd5-413c-af47-aaf1f38aa84d.json

@@ -0,0 +1,4 @@
+{
+  "type" : "bugfix",
+  "description" : "Fix hitting enter inside braces will produce an extra newline (#3270)"
+}

jetbrains-core/resources/META-INF/plugin.xml

@@ -320,7 +320,7 @@ with what features/services are supported.
         <registryKey key="aws.toolkit.developerMode" description="Enables features to facilitate development of the toolkit" restartRequired="false" defaultValue="false"/>
         <typedHandler implementation="software.aws.toolkits.jetbrains.services.codewhisperer.editor.CodeWhispererTypedHandler"/>
         <editorFactoryListener implementation="software.aws.toolkits.jetbrains.services.codewhisperer.editor.CodeWhispererEditorListener"/>
-        <editorActionHandler action="EditorEnter" implementationClass="software.aws.toolkits.jetbrains.services.codewhisperer.editor.CodeWhispererEnterHandler"/>
+        <editorActionHandler action="EditorEnter" implementationClass="software.aws.toolkits.jetbrains.services.codewhisperer.editor.CodeWhispererEnterHandler" order="first, before editorEnter"/>
         <actionPromoter order="last" implementation="software.aws.toolkits.jetbrains.services.codewhisperer.actions.CodeWhispererActionPromoter"/>
     </extensions>
 

jetbrains-core/src/software/aws/toolkits/jetbrains/services/codewhisperer/editor/CodeWhispererEnterHandler.kt

@@ -12,11 +12,11 @@ import software.aws.toolkits.jetbrains.services.codewhisperer.service.CodeWhispe
 import software.aws.toolkits.telemetry.CodewhispererAutomatedTriggerType
 import software.aws.toolkits.telemetry.CodewhispererTriggerType
 
-class CodeWhispererEnterHandler(originalHandler: EditorActionHandler) :
+class CodeWhispererEnterHandler(private val originalHandler: EditorActionHandler) :
     EnterHandler(originalHandler),
     CodeWhispererAutoTriggerHandler {
     override fun executeWriteAction(editor: Editor, caret: Caret?, dataContext: DataContext?) {
-        super.executeWriteAction(editor, caret, dataContext)
+        originalHandler.execute(editor, caret, dataContext)
         if (!CodeWhispererService.getInstance().canDoInvocation(editor, CodewhispererTriggerType.AutoTrigger)) {
             return
         }

jetbrains-core/tst/software/aws/toolkits/jetbrains/services/codewhisperer/CodeWhispererTestBase.kt

@@ -122,7 +122,7 @@ open class CodeWhispererTestBase {
         editorManager = CodeWhispererEditorManager.getInstance()
         settingsManager = CodeWhispererSettings.getInstance()
 
-        setPrompt(pythonFileName, pythonTestLeftContext)
+        setFileContext(pythonFileName, pythonTestLeftContext, "")
 
         originalExplorerActionState = stateManager.state
         originalSettings = settingsManager.state
@@ -178,10 +178,10 @@ open class CodeWhispererTestBase {
         assertThat(actual).isEqualTo(expected)
     }
 
-    fun setPrompt(filename: String, prompt: String) {
-        projectRule.fixture.configureByText(filename, prompt)
+    fun setFileContext(filename: String, leftContext: String, rightContext: String) {
+        projectRule.fixture.configureByText(filename, leftContext + rightContext)
         runInEdtAndWait {
-            projectRule.fixture.editor.caretModel.primaryCaret.moveToOffset(projectRule.fixture.editor.document.textLength)
+            projectRule.fixture.editor.caretModel.primaryCaret.moveToOffset(leftContext.length)
         }
     }
 }

jetbrains-core/tst/software/aws/toolkits/jetbrains/services/codewhisperer/CodeWhispererUserActionsTest.kt

@@ -15,13 +15,14 @@ import com.intellij.openapi.actionSystem.IdeActions.ACTION_EDITOR_TEXT_START_WIT
 import com.intellij.openapi.command.WriteCommandAction
 import com.intellij.openapi.ui.popup.JBPopup
 import com.intellij.testFramework.runInEdtAndWait
+import org.assertj.core.api.Assertions.assertThat
 import org.junit.Before
 import org.junit.Test
 import org.mockito.kotlin.any
 import org.mockito.kotlin.argumentCaptor
 import org.mockito.kotlin.timeout
-import org.mockito.kotlin.times
 import org.mockito.kotlin.verify
+import software.aws.toolkits.jetbrains.services.codewhisperer.CodeWhispererTestUtil.javaFileName
 import software.aws.toolkits.jetbrains.services.codewhisperer.CodeWhispererTestUtil.pythonFileName
 import software.aws.toolkits.jetbrains.services.codewhisperer.CodeWhispererTestUtil.pythonTestLeftContext
 import software.aws.toolkits.jetbrains.services.codewhisperer.explorer.CodeWhispererExplorerActionManager
@@ -104,9 +105,26 @@ class CodeWhispererUserActionsTest : CodeWhispererTestBase() {
         testHittingEnterAfterWhitespaceCharsShouldTriggerCodeWhisperer("$pythonTestLeftContext\n", 3)
     }
 
+    @Test
+    fun `test hitting enter inside braces in Java file should auto-trigger CodeWhisperer and keep the formatting correct`() {
+        val testLeftContext = "public class Test {\n    public static void main() {"
+        val testRightContext = "}\n}"
+        setFileContext(javaFileName, testLeftContext, testRightContext)
+        CodeWhispererExplorerActionManager.getInstance().setAutoEnabled(true)
+        projectRule.fixture.type('\n')
+        val expectedFileContext = "$testLeftContext\n        \n    $testRightContext"
+        assertThat(projectRule.fixture.editor.document.text).isEqualTo(expectedFileContext)
+        val popupCaptor = argumentCaptor<JBPopup>()
+        verify(popupManagerSpy, timeout(5000))
+            .showPopup(any(), any(), any(), any(), any(), popupCaptor.capture(), any(), any())
+        runInEdtAndWait {
+            popupManagerSpy.closePopup(popupCaptor.lastValue)
+        }
+    }
+
     private fun testHittingEnterAfterWhitespaceCharsShouldTriggerCodeWhisperer(prompt: String, times: Int) {
         CodeWhispererExplorerActionManager.getInstance().setAutoEnabled(true)
-        setPrompt(pythonFileName, prompt)
+        setFileContext(pythonFileName, prompt, "")
         projectRule.fixture.type('\n')
         val popupCaptor = argumentCaptor<JBPopup>()
         verify(popupManagerSpy, timeout(5000).atLeast(times))