Use semver ranges

Author: rbuckton

Gulpfile.js

@@ -24,10 +24,9 @@ const baselineAccept = require("./scripts/build/baselineAccept");
 const cmdLineOptions = require("./scripts/build/options");
 const exec = require("./scripts/build/exec");
 const browserify = require("./scripts/build/browserify");
-const debounce = require("./scripts/build/debounce");
 const prepend = require("./scripts/build/prepend");
 const { removeSourceMaps } = require("./scripts/build/sourcemaps");
-const { CancelSource, CancelError } = require("./scripts/build/cancellation");
+const { CancellationTokenSource, CancelError, delay, Semaphore } = require("prex");
 const { libraryTargets, generateLibs } = require("./scripts/build/lib");
 const { runConsoleTests, cleanTestDirs, writeTestConfigFile, refBaseline, localBaseline, refRwcBaseline, localRwcBaseline } = require("./scripts/build/tests");
 
@@ -556,35 +555,61 @@ gulp.task(
     "Watches for changes to the build inputs for built/local/run.js, then executes runtests-parallel.",
     ["build-rules", "watch-runner", "watch-services", "watch-lssl"],
     () => {
-        /** @type {CancelSource | undefined} */
-        let runTestsSource;
-
-        const fn = debounce(() => {
-            runTests().catch(error => {
-                if (error instanceof CancelError) {
+        const runTestsSemaphore = new Semaphore(1);
+        const fn = async () => {
+            try {
+                // Ensure only one instance of the test runner is running at any given time.
+                if (runTestsSemaphore.count > 0) {
+                    await runTestsSemaphore.wait();
+                    try {
+                        // Wait for any concurrent recompilations to complete...
+                        try {
+                            await delay(100);
+                            while (project.hasRemainingWork()) {
+                                await project.waitForWorkToComplete();
+                                await delay(500);
+                            }
+                        }
+                        catch (e) {
+                            if (e instanceof CancelError) return;
+                            throw e;
+                        }
+
+                        // cancel any pending or active test run if a new recompilation is triggered
+                        const runTestsSource = new CancellationTokenSource();
+                        project.waitForWorkToStart().then(() => {
+                            runTestsSource.cancel();
+                        });
+                    
+                        if (cmdLineOptions.tests || cmdLineOptions.failed) {
+                            await runConsoleTests(runJs, "mocha-fivemat-progress-reporter", /*runInParallel*/ false, /*watchMode*/ true, runTestsSource.token);
+                        }
+                        else {
+                            await runConsoleTests(runJs, "min", /*runInParallel*/ true, /*watchMode*/ true, runTestsSource.token);
+                        }
+                    }
+                    finally {
+                        runTestsSemaphore.release();
+                    }
+                }
+            }
+            catch (e) {
+                if (e instanceof CancelError) {
                     log.warn("Operation was canceled");
                 }
                 else {
-                    log.error(error);
+                    log.error(e);
                 }
-            });
-        }, /*timeout*/ 100, { max: 500 });
+            }
+        };
 
-        gulp.watch(watchPatterns, () => project.wait(runTestsSource && runTestsSource.token).then(fn));
+        gulp.watch(watchPatterns, (e) => fn());
 
         // NOTE: gulp.watch is far too slow when watching tests/cases/**/* as it first enumerates *every* file
         const testFilePattern = /(\.ts|[\\/]tsconfig\.json)$/;
         fs.watch("tests/cases", { recursive: true }, (_, file) => {
-            if (testFilePattern.test(file)) project.wait(runTestsSource && runTestsSource.token).then(fn);
+            if (testFilePattern.test(file)) fn();
         });
-
-        function runTests() {
-            if (runTestsSource) runTestsSource.cancel();
-            runTestsSource = new CancelSource();
-            return cmdLineOptions.tests || cmdLineOptions.failed
-                ? runConsoleTests(runJs, "mocha-fivemat-progress-reporter", /*runInParallel*/ false, /*watchMode*/ true, runTestsSource.token)
-                : runConsoleTests(runJs, "min", /*runInParallel*/ true, /*watchMode*/ true, runTestsSource.token);
-        }
     });
 
 gulp.task("clean-built", /*help*/ false, [`clean:${diagnosticInformationMapTs}`], () => del(["built"]));

package.json

@@ -81,6 +81,7 @@
         "mocha": "latest",
         "mocha-fivemat-progress-reporter": "latest",
         "plugin-error": "latest",
+        "prex": "^0.4.3",
         "q": "latest",
         "remove-internal": "^2.9.2",
         "run-sequence": "latest",

scripts/build/cancellation.js

@@ -3,7 +3,7 @@ const cp = require("child_process");
 const log = require("fancy-log"); // was `require("gulp-util").log (see https://github.com/gulpjs/gulp-util)
 const isWin = /^win/.test(process.platform);
 const chalk = require("./chalk");
-const { CancelToken, CancelError } = require("./cancellation");
+const { CancelError } = require("prex");
 
 module.exports = exec;
 
@@ -15,24 +15,28 @@ module.exports = exec;
  *
  * @typedef ExecOptions
  * @property {boolean} [ignoreExitCode]
- * @property {CancelToken} [cancelToken]
+ * @property {import("prex").CancellationToken} [cancelToken]
  */
 function exec(cmd, args, options = {}) {
     return /**@type {Promise<{exitCode: number}>}*/(new Promise((resolve, reject) => {
+        if (options.cancelToken) {
+            options.cancelToken.throwIfCancellationRequested();
+        }
+    
         log(`> ${chalk.green(cmd)} ${args.join(" ")}`);
         // TODO (weswig): Update child_process types to add windowsVerbatimArguments to the type definition
         const subshellFlag = isWin ? "/c" : "-c";
         const command = isWin ? [possiblyQuote(cmd), ...args] : [`${cmd} ${args.join(" ")}`];
         const ex = cp.spawn(isWin ? "cmd" : "/bin/sh", [subshellFlag, ...command], { stdio: "inherit", windowsVerbatimArguments: true });
-        const subscription = options.cancelToken && options.cancelToken.subscribe(() => {
+        const subscription = options.cancelToken && options.cancelToken.register(() => {
             log(`${chalk.red("killing")} '${chalk.green(cmd)} ${args.join(" ")}'...`);
             ex.kill("SIGINT");
             ex.kill("SIGTERM");
             ex.kill();
             reject(new CancelError());
         });
         ex.on("exit", exitCode => {
-            subscription && subscription.unsubscribe();
+            if (subscription) subscription.unregister();
             if (exitCode === 0 || options.ignoreExitCode) {
                 resolve({ exitCode });
             }
@@ -41,7 +45,7 @@ function exec(cmd, args, options = {}) {
             }
         });
         ex.on("error", error => {
-            subscription && subscription.unsubscribe();
+            if (subscription) subscription.unregister();
             reject(error);
         });
     }));