vscode: migrate to more type-safe assert impl

editors/code/src/installation/download_file.ts

@@ -2,8 +2,7 @@ import fetch from "node-fetch";
 import * as fs from "fs";
 import * as stream from "stream";
 import * as util from "util";
-import { strict as assert } from "assert";
+import { log, assert } from "../util";
-import { log } from "../util";
 
 const pipeline = util.promisify(stream.pipeline);
 

editors/code/src/installation/server.ts

@@ -1,13 +1,12 @@
 import * as vscode from "vscode";
 import * as path from "path";
-import { strict as assert } from "assert";
 import { promises as dns } from "dns";
 import { spawnSync } from "child_process";
 
 import { BinarySource } from "./interfaces";
 import { fetchArtifactReleaseInfo } from "./fetch_artifact_release_info";
 import { downloadArtifact } from "./download_artifact";
-import { log } from "../util";
+import { log, assert } from "../util";
 
 export async function ensureServerBinary(source: null | BinarySource): Promise<null | string> {
     if (!source) {

editors/code/src/util.ts

@@ -1,22 +1,26 @@
 import * as lc from "vscode-languageclient";
 import * as vscode from "vscode";
+import { strict as nodeAssert } from "assert";
 
-let enabled: boolean = false;
+export function assert(condition: unknown, explanation: string): asserts condition {
+    nodeAssert(condition, explanation);
+}
 
 export const log = {
+    enabled: true,
     debug(message?: any, ...optionalParams: any[]): void {
-        if (!enabled) return;
+        if (!log.enabled) return;
         // eslint-disable-next-line no-console
         console.log(message, ...optionalParams);
     },
     error(message?: any, ...optionalParams: any[]): void {
-        if (!enabled) return;
+        if (!log.enabled) return;
         debugger;
         // eslint-disable-next-line no-console
         console.error(message, ...optionalParams);
     },
     setEnabled(yes: boolean): void {
-        enabled = yes;
+        log.enabled = yes;
     }
 };