some minor changes

README.md

@@ -79,6 +79,8 @@ The plugin is still on an early stage, check [ISSUES.md](./ISSUES.md) for known
   - (Windows) `$HOME\AppData\Local\JetBrains\<Product>\log\idea.log`
   - (Macos) `~/Library/Caches/<Product>/log/idea.log`
 - If the IDE is freezing, try check also the `threadDumps-freeze-***` files under the log folder.
+
+For showing debug/trace log, add `lean4ij:all` in `MENU > Help > Diagnostic Tools > Debug Log Settings` and restart, see [How-to-enable-debug-logging-in-IntelliJ-IDEA](https://youtrack.jetbrains.com/articles/SUPPORT-A-43/How-to-enable-debug-logging-in-IntelliJ-IDEA) for more docs.
 
 ## Acknowledgments
 

src/main/kotlin/lean4ij/language/Lean4PsiFile.kt

@@ -15,6 +15,6 @@ class Lean4PsiFile(viewProvider: FileViewProvider) : PsiFileBase(viewProvider, L
     }
 
     override fun toString(): String {
-        return "Lean4 Psi File"
+        return "Lean4PsiFile($virtualFile)"
     }
 }

src/main/kotlin/lean4ij/lsp/LeanLanguageServerFactory.kt

@@ -61,7 +61,7 @@ class LeanLanguageServerFactory : LanguageServerFactory, LanguageServerEnablemen
                 completionFeature = LeanLSPCompletionFeature()
             }
             // waiting for lsp4ij https://github.com/redhat-developer/lsp4ij/pull/586
-            /*override*/ fun isEnabled(file: VirtualFile): Boolean {
+            override fun isEnabled(file: VirtualFile): Boolean {
                 return FileEditorManager.getInstance(project).selectedTextEditor?.let {
                     it.virtualFile == file
                 }?: false

src/main/kotlin/lean4ij/lsp/data/InteractiveDiagnosticsParams.kt

@@ -1,6 +1,5 @@
 package lean4ij.lsp.data
 
-import io.kinference.ndarray.extensions.inferType
 import lean4ij.util.Constants
 import org.eclipse.lsp4j.TextDocumentIdentifier