From fc9a595992a440ce0f7ef98f06eaa67f1b1a2715 Mon Sep 17 00:00:00 2001
From: "vs-code-engineering[bot]"
 <122617954+vs-code-engineering[bot]@users.noreply.github.com>
Date: Fri, 26 Jun 2026 18:28:43 +0000
Subject: [PATCH] fix: drop diagnostics with missing range at the language
 diagnostics boundary (fixes #323148) (#323153)
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* fix: drop diagnostics with missing range at the language diagnostics boundary

Other extensions can publish vscode.Diagnostic entries whose `range` is
undefined (violating the non-nullable `range: Range` type via an `any` cast).
These reach copilot verbatim through `vscode.languages.getDiagnostics()` and
crash the many consumers that dereference `diagnostic.range` - notably the
`LintErrors.getData` telemetry path that scans every extension's diagnostics
via `getAllDiagnostics()`. Sanitize at the boundary service so every consumer
is protected once, and log dropped entries so the producer stays diagnosable.

Fixes microsoft/vscode#323148

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix: Copilot - Test lint — use strict equality for range null/undefined check

The eqeqeq ESLint rule (configured as 'warn', enforced with --max-warnings=0)
flagged `range != null` in _dropMalformedDiagnostics. Replace the loose
equality with an explicit strict check that preserves the original semantics
of dropping diagnostics whose range is either null or undefined.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: vs-code-engineering[bot] <122617954+vs-code-engineering[bot]@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 .../vscode/languageDiagnosticsServiceImpl.ts  | 32 +++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/extensions/copilot/src/platform/languages/vscode/languageDiagnosticsServiceImpl.ts b/extensions/copilot/src/platform/languages/vscode/languageDiagnosticsServiceImpl.ts
index 5af945d1b66..6505f80f3ab 100644
--- a/extensions/copilot/src/platform/languages/vscode/languageDiagnosticsServiceImpl.ts
+++ b/extensions/copilot/src/platform/languages/vscode/languageDiagnosticsServiceImpl.ts
@@ -4,18 +4,46 @@
  *--------------------------------------------------------------------------------------------*/
 
 import * as vscode from 'vscode';
+import { ILogService } from '../../log/common/logService';
 import { AbstractLanguageDiagnosticsService } from '../common/languageDiagnosticsService';
 
 export class LanguageDiagnosticsServiceImpl extends AbstractLanguageDiagnosticsService {
 	private static ignoredSchemes = new Set(['git', 'chat-editing-snapshot-text-model', 'chat-editing-text-model']);
 	override onDidChangeDiagnostics: vscode.Event<vscode.DiagnosticChangeEvent> = vscode.languages.onDidChangeDiagnostics;
 
+	constructor(
+		@ILogService private readonly _logService: ILogService,
+	) {
+		super();
+	}
+
 	override getDiagnostics(resource: vscode.Uri): vscode.Diagnostic[] {
-		return vscode.languages.getDiagnostics(resource);
+		return this._dropMalformedDiagnostics(vscode.languages.getDiagnostics(resource));
 	}
 
 	override getAllDiagnostics(): [vscode.Uri, vscode.Diagnostic[]][] {
 		return vscode.languages.getDiagnostics()
-			.filter(([uri]) => !LanguageDiagnosticsServiceImpl.ignoredSchemes.has(uri.scheme));
+			.filter(([uri]) => !LanguageDiagnosticsServiceImpl.ignoredSchemes.has(uri.scheme))
+			.map(([uri, diagnostics]): [vscode.Uri, vscode.Diagnostic[]] => [uri, this._dropMalformedDiagnostics(diagnostics)]);
+	}
+
+	/**
+	 * Diagnostics are produced by arbitrary extensions and reach us verbatim through the
+	 * `vscode.languages.getDiagnostics` API. An extension can publish an entry that violates the
+	 * {@link vscode.Diagnostic} contract at runtime - most notably with a missing `range` assigned
+	 * through an `any` cast - and such an entry crashes the many consumers that dereference
+	 * `diagnostic.range`. Drop the malformed entries here, at the extension boundary, and surface
+	 * the occurrence so the underlying producer stays diagnosable.
+	 */
+	private _dropMalformedDiagnostics(diagnostics: vscode.Diagnostic[]): vscode.Diagnostic[] {
+		const valid = diagnostics.filter(diagnostic => {
+			const range: vscode.Range | null | undefined = diagnostic.range;
+			return range !== null && range !== undefined;
+		});
+		const dropped = diagnostics.length - valid.length;
+		if (dropped > 0) {
+			this._logService.warn(`[LanguageDiagnosticsService] Ignored ${dropped} diagnostic(s) with a missing range received from the diagnostics API.`);
+		}
+		return valid;
 	}
 }