diff --git a/TODO b/TODO
index 4022e0d..edac1bd 100644
--- a/TODO
+++ b/TODO
@@ -1,26 +1,25 @@
 MVP
 ===
 - lint everything
-- when fixing last issue, it doesn't co away.
 
 TODO
 ====
 - lint current file
 - [v] command clear all issues
 
 Long Term Desired Features
 ==========================
 - Fancy UIs for
     - arc patch
     - arc todo
     - arc unit
     - arc browse
     - arc paste (upload and download)
 - list open Differential in repo (for review)
 - get hovercard (content) for any object
 - push notifications from website ?
 - preview Remarkup
 - some magic to help the External Editor Link
 - arc lint: special-case some messages for better visibility (find more range/information.)
 - arc lint: support auto-fix (apply diff)
 - arc lint: `locations` field may be parsed into `relatedInformation`.
diff --git a/src/arc_lint.ts b/src/arc_lint.ts
index 60aa9d4..2635d3f 100644
--- a/src/arc_lint.ts
+++ b/src/arc_lint.ts
@@ -1,135 +1,138 @@
 import * as vscode from 'vscode';
 import * as execa from 'execa';
 import * as path from 'path';
 
 import { nonNeg } from './misc';
 import { ArcanistLintMessage } from './arcanist_types';
 import { setupCustomTranslators } from './arc_lint_translators';
 
 
 export function setup() {
     setupCustomTranslators(customLintTranslator);
     updateLintSeverityMap();
 }
 
 export function lintFile(document: vscode.TextDocument, errorCollection: vscode.DiagnosticCollection) {
     if (document.uri.scheme !== "file") { return; }
 
     function handleExecResult(value: execa.ExecaReturnValue<string>) {
-        if (!value.stdout) { return; }
+        if (!value.stdout) {
+            errorCollection.delete(document.uri);
+            return;
+        }
         try {
             const lintMessages = JSON.parse(value.stdout);
 
             for (const filename in lintMessages) {
                 // TODO: This only probably works because we call arc with a single file.
                 errorCollection.set(document.uri, lintJsonToDiagnostics(lintMessages[filename]));
             }
         } catch {
             console.log("ppfff");
         }
     }
 
     const filename = document.uri.path;
 
     execa(
         'arc', ['lint', '--output', 'json', '--', path.basename(filename)],
         { cwd: path.dirname(filename) },
     ).then(handleExecResult, handleExecResult);
 }
 
 /**
 input:
 ```
 {
     "line": 248,
     "char": 23,
     "code": "SPELL1",
     "severity": "warning",
     "name": "Possible Spelling Mistake",
     "description": "Possible spelling error. You wrote 'seperator', but did you mean 'separator'?",
     "original": "Seperator",
     "replacement": "Separator",
     "granularity": 1,
     "locations": [],
     "bypassChangedLineFiltering": null,
     "context": "    magic = COLOR_RED;\n    break;\n  case 30:\n    // printf(\"Record Seperator\");\n    magic = COLOR_BLUE;\n    break;\n  case 31:"
 }
 ```
 output:
 ```
 {
     code: '',
     message: 'cannot assign twice to immutable variable `x`',
     range: new vscode.Range(new vscode.Position(3, 4), new vscode.Position(3, 10)),
     severity: vscode.DiagnosticSeverity.Error,
     source: '',
     relatedInformation: [
         new vscode.DiagnosticRelatedInformation(new vscode.Location(document.uri, new vscode.Range(new vscode.Position(1, 8), new vscode.Position(1, 9))), 'first assignment to `x`')
     ]
 }
 ```
 
 Possible Extra features:
 - quick-fix to apply patch
 - try to get better message by parsing `description` field (per message code...)
 - `locations` may be parsed into `relatedInformation`.
 */
 export type LintTranslator = (lint: ArcanistLintMessage) => vscode.Diagnostic;
 let customLintTranslator: Map<String, LintTranslator> = new Map();
 
 
 export function defaultLintTranslator(lint: ArcanistLintMessage): vscode.Diagnostic {
     return {
         code: lint.code,
         message: message(lint),
         severity: severity(lint),
         source: 'arc lint',
         range: new vscode.Range(
             lint.line - 1, nonNeg(lint.char - 2), // it's an artificial 3-chars wide thing.
             lint.line - 1, lint.char + 1),
     };
 }
 
 function message(lint: ArcanistLintMessage) {
     if (lint.description) { return lint.name + ": " + lint.description; }
     return lint.name;
 }
 
 let lintSeverityMap: Map<String, vscode.DiagnosticSeverity>;
 export function updateLintSeverityMap(): void {
     let config = vscode.workspace.getConfiguration('arc-vscode.lint');
     let maxLevel: vscode.DiagnosticSeverity;
     switch (config.maxDiagnosticsLevel as string) {
         case 'hint': maxLevel = vscode.DiagnosticSeverity.Hint; break;
         case 'info': maxLevel = vscode.DiagnosticSeverity.Information; break;
         case 'warning': maxLevel = vscode.DiagnosticSeverity.Warning; break;
         case 'error':
         default:
             maxLevel = vscode.DiagnosticSeverity.Error; break;
     }
 
     function capped(level: vscode.DiagnosticSeverity): vscode.DiagnosticSeverity {
         return level > maxLevel ? level : maxLevel;
     }
 
     lintSeverityMap = new Map();
     lintSeverityMap.set('disabled', capped(vscode.DiagnosticSeverity.Hint));
     lintSeverityMap.set('autofix', capped(vscode.DiagnosticSeverity.Information));
     lintSeverityMap.set('advice', capped(vscode.DiagnosticSeverity.Information));
     lintSeverityMap.set('warning', capped(vscode.DiagnosticSeverity.Warning));
     lintSeverityMap.set('error', capped(vscode.DiagnosticSeverity.Error));
 }
 
 function severity(lint: ArcanistLintMessage): vscode.DiagnosticSeverity {
     return lintSeverityMap.get(lint.severity as string) || vscode.DiagnosticSeverity.Error;
 }
 
 
 function lintJsonToDiagnostics(lintResults: Array<ArcanistLintMessage>): vscode.Diagnostic[] {
     function translate(lint: ArcanistLintMessage): vscode.Diagnostic {
         let t = customLintTranslator.get(lint.code) || defaultLintTranslator;
         return t(lint);
     }
 
     return lintResults.map(translate);
 }