fix: abort callbacks after LanguageProvider.closeDocument called

Author: davidjb

packages/ace-linters/src/language-provider.ts

@@ -322,9 +322,13 @@ export class LanguageProvider {
                 if (!$timer)
                     $timer =
                         setTimeout(() => {
-                            let cursor = editor.getCursorPosition();
                             let sessionLanguageProvider = this.$getSessionLanguageProvider(editor.session);
+                            if (!sessionLanguageProvider) {
+                                $timer = undefined;
+                                return;
+                            }
 
+                            let cursor = editor.getCursorPosition();
                             this.$messageController.findDocumentHighlights(this.$getFileName(editor.session), fromPoint(cursor), sessionLanguageProvider.$applyDocumentHighlight);
                             $timer = undefined;
                         }, 50);
@@ -372,6 +376,11 @@ export class LanguageProvider {
             if (!actionTimer)
                 actionTimer =
                     setTimeout(() => {
+                        if (!this.$getSessionLanguageProvider(editor.session)) {
+                            actionTimer = undefined;
+                            return;
+                        }
+
                         //TODO: no need to send request on empty
                         let selection = editor.getSelection().getRange();
                         let cursor = editor.getCursorPosition();
@@ -508,6 +517,8 @@ export class LanguageProvider {
     }
 
     provideSignatureHelp(session: Ace.EditSession, position: Ace.Point, callback?: (signatureHelp: Tooltip | undefined) => void) {
+        if (!this.$getSessionLanguageProvider(session))
+            return;
         this.$messageController.provideSignatureHelp(this.$getFileName(session), fromPoint(position), (signatureHelp) => callback && callback(fromSignatureHelp(signatureHelp)));
     }
 

packages/ace-linters/tests/unit/language-provider.tests.ts

@@ -80,9 +80,9 @@ describe('LanguageProvider tests', () => {
                 },
                 completionResolve: true,
                 format: true,
-                documentHighlights: false,
+                documentHighlights: true,
                 signatureHelp: false,
-                codeActions: false
+                codeActions: true
             }
         });
         languageProvider.registerEditor(editor);
@@ -460,6 +460,15 @@ describe('LanguageProvider tests', () => {
 
     })
 
+    it('should not error from callbacks after closeDocument', (done) => {
+        languageProvider.closeDocument(editor.session);
+        expect(() => languageProvider.provideSignatureHelp(editor.session, null, null)).not.to.throw();
+
+        // Check for exceptions from changeSelection from documentHighlights and $provideCodeActions
+        editor.session.setValue("example");
+        setTimeout(done, 600);
+    })
+
     after(() => {
         client.removeAllListeners();
         ctx.removeAllListeners();