Fix EDT issue on CodeWhispererEditorListener

Author: rli

.changes/next-release/bugfix-c7239939-2067-469a-809e-594d2c95594b.json

@@ -0,0 +1,4 @@
+{
+  "type" : "bugfix",
+  "description" : "Fix 'Slow operations are prohibited on EDT.' when Amazon Q is determining if a file supports inline suggestions (#4823)"
+}

plugins/amazonq/codewhisperer/jetbrains-community/src/software/aws/toolkits/jetbrains/services/codewhisperer/editor/CodeWhispererEditorListener.kt

@@ -8,6 +8,7 @@ import com.intellij.openapi.editor.event.DocumentEvent
 import com.intellij.openapi.editor.event.EditorFactoryEvent
 import com.intellij.openapi.editor.event.EditorFactoryListener
 import com.intellij.openapi.editor.impl.EditorImpl
+import com.intellij.openapi.vfs.findPsiFile
 import com.intellij.psi.PsiDocumentManager
 import software.aws.toolkits.jetbrains.services.codewhisperer.explorer.isCodeWhispererEnabled
 import software.aws.toolkits.jetbrains.services.codewhisperer.language.programmingLanguage
@@ -17,27 +18,26 @@ import software.aws.toolkits.jetbrains.services.codewhisperer.telemetry.CodeWhis
 class CodeWhispererEditorListener : EditorFactoryListener {
     override fun editorCreated(event: EditorFactoryEvent) {
         val editor = (event.editor as? EditorImpl) ?: return
-        editor.project?.let { project ->
-            PsiDocumentManager.getInstance(project).getPsiFile(editor.document)?.programmingLanguage() ?. let { language ->
-                // If language is not supported by CodeWhisperer, no action needed
-                if (!language.isCodeCompletionSupported()) return
-                // If language is supported, install document listener for CodeWhisperer service
-                editor.document.addDocumentListener(
-                    object : BulkAwareDocumentListener {
-                        // TODO: Track only deletion changes within the current 5-min interval which will give
-                        // the most accurate code percentage data.
-                        override fun documentChanged(event: DocumentEvent) {
-                            if (!isCodeWhispererEnabled(project)) return
-                            CodeWhispererInvocationStatus.getInstance().documentChanged()
-                            CodeWhispererCodeCoverageTracker.getInstance(project, language).apply {
-                                activateTrackerIfNotActive()
-                                documentChanged(event)
-                            }
-                        }
-                    },
-                    editor.disposable
-                )
-            }
-        }
+        val project = editor.project ?: return
+
+        val language = editor.virtualFile.programmingLanguage()
+        // If language is not supported by CodeWhisperer, no action needed
+        if (!language.isCodeCompletionSupported()) return
+        // If language is supported, install document listener for CodeWhisperer service
+        editor.document.addDocumentListener(
+            object : BulkAwareDocumentListener {
+                // TODO: Track only deletion changes within the current 5-min interval which will give
+                // the most accurate code percentage data.
+                override fun documentChanged(event: DocumentEvent) {
+                    if (!isCodeWhispererEnabled(project)) return
+                    CodeWhispererInvocationStatus.getInstance().documentChanged()
+                    CodeWhispererCodeCoverageTracker.getInstance(project, language).apply {
+                        activateTrackerIfNotActive()
+                        documentChanged(event)
+                    }
+                }
+            },
+            editor.disposable
+        )
     }
 }