Remove unused cancellation from build (microsoft#50658)

Author: jakebailey

package-lock.json

@@ -90,7 +90,6 @@
         "mocha-fivemat-progress-reporter": "latest",
         "ms": "^2.1.3",
         "node-fetch": "^2.6.7",
-        "prex": "^0.4.7",
         "source-map-support": "latest",
         "typescript": "^4.8.2",
         "vinyl": "latest",

package.json

@@ -6,7 +6,6 @@ const path = require("path");
 const mkdirP = require("mkdirp");
 const log = require("fancy-log");
 const cmdLineOptions = require("./options");
-const { CancellationToken } = require("prex");
 const { exec } = require("./utils");
 const { findUpFile } = require("./findUpDir");
 
@@ -22,9 +21,8 @@ exports.localTest262Baseline = "internal/baselines/test262/local";
  * @param {string} defaultReporter
  * @param {boolean} runInParallel
  * @param {boolean} watchMode
- * @param {import("prex").CancellationToken} [cancelToken]
  */
-async function runConsoleTests(runJs, defaultReporter, runInParallel, watchMode, cancelToken = CancellationToken.none) {
+async function runConsoleTests(runJs, defaultReporter, runInParallel, watchMode) {
     let testTimeout = cmdLineOptions.timeout;
     const tests = cmdLineOptions.tests;
     const inspect = cmdLineOptions.break || cmdLineOptions.inspect;
@@ -38,7 +36,6 @@ async function runConsoleTests(runJs, defaultReporter, runInParallel, watchMode,
     const shardId = +cmdLineOptions.shardId || undefined;
     if (!cmdLineOptions.dirty) {
         await cleanTestDirs();
-        cancelToken.throwIfCancellationRequested();
     }
 
     if (fs.existsSync(testConfigFile)) {
@@ -121,9 +118,7 @@ async function runConsoleTests(runJs, defaultReporter, runInParallel, watchMode,
 
     try {
         setNodeEnvToDevelopment();
-        const { exitCode } = await exec(process.execPath, args, {
-            cancelToken,
-        });
+        const { exitCode } = await exec(process.execPath, args);
         if (exitCode !== 0) {
             errorStatus = exitCode;
             error = new Error(`Process exited with status code ${errorStatus}.`);
@@ -132,8 +127,8 @@ async function runConsoleTests(runJs, defaultReporter, runInParallel, watchMode,
             // finally, do a sanity check and build the compiler with the built version of itself
             log.info("Starting sanity check build...");
             // Cleanup everything except lint rules (we'll need those later and would rather not waste time rebuilding them)
-            await exec("gulp", ["clean-tsc", "clean-services", "clean-tsserver", "clean-lssl", "clean-tests"], { cancelToken });
-            const { exitCode } = await exec("gulp", ["local", "--lkg=false"], { cancelToken });
+            await exec("gulp", ["clean-tsc", "clean-services", "clean-tsserver", "clean-lssl", "clean-tests"]);
+            const { exitCode } = await exec("gulp", ["local", "--lkg=false"]);
             if (exitCode !== 0) {
                 errorStatus = exitCode;
                 error = new Error(`Sanity check build process exited with status code ${errorStatus}.`);

scripts/build/tests.js

@@ -14,7 +14,6 @@ const ts = require("../../lib/typescript");
 const chalk = require("chalk");
 const which = require("which");
 const { spawn } = require("child_process");
-const { CancellationToken, CancelError, Deferred } = require("prex");
 const { Readable, Duplex } = require("stream");
 
 /**
@@ -25,26 +24,17 @@ const { Readable, Duplex } = require("stream");
  *
  * @typedef ExecOptions
  * @property {boolean} [ignoreExitCode]
- * @property {import("prex").CancellationToken} [cancelToken]
  * @property {boolean} [hidePrompt]
  * @property {boolean} [waitForExit=true]
  */
 async function exec(cmd, args, options = {}) {
     return /**@type {Promise<{exitCode: number}>}*/(new Promise((resolve, reject) => {
-        const { ignoreExitCode, cancelToken = CancellationToken.none, waitForExit = true } = options;
-        cancelToken.throwIfCancellationRequested();
+        const { ignoreExitCode, waitForExit = true } = options;
 
         if (!options.hidePrompt) log(`> ${chalk.green(cmd)} ${args.join(" ")}`);
         const proc = spawn(which.sync(cmd), args, { stdio: waitForExit ? "inherit" : "ignore" });
-        const registration = cancelToken.register(() => {
-            log(`${chalk.red("killing")} '${chalk.green(cmd)} ${args.join(" ")}'...`);
-            proc.kill("SIGINT");
-            proc.kill("SIGTERM");
-            reject(new CancelError());
-        });
         if (waitForExit) {
             proc.on("exit", exitCode => {
-                registration.unregister();
                 if (exitCode === 0 || ignoreExitCode) {
                     resolve({ exitCode });
                 }
@@ -53,7 +43,6 @@ async function exec(cmd, args, options = {}) {
                 }
             });
             proc.on("error", error => {
-                registration.unregister();
                 reject(error);
             });
         }
@@ -395,6 +384,15 @@ function rm(dest, opts) {
 }
 exports.rm = rm;
 
+class Deferred {
+    constructor() {
+        this.promise = new Promise((resolve, reject) => {
+            this.resolve = resolve;
+            this.reject = reject;
+        });
+    }
+}
+
 class Debouncer {
     /**
      * @param {number} timeout