Remove 'supervise' mode in favor of 'watch' mode

There's no point in keeping the process alive on 'watch' mode, but
being unable to reload on any file changes. Before this fix, we would
need to use 'watch' and 'supervise' modes together to achieve this.

This fix makes 'watch' mode behave like 'supervise' mode, but getting
rid of the latter.

Readme.md

@@ -23,7 +23,7 @@ wds --inspect some-test.test.ts
 
 - Builds and runs TypeScript really fast (using [`swc`](https://github.com/swc-project/swc) or [`esbuild`](https://github.com/evanw/esbuild))
 - Incrementally rebuilds only what has changed in the `--watch` mode, and restarts the process when files change
-- Supervises the node.js process with `--supervise` to keep incremental context around on process crash, and can restart on demand in the `--commands` mode
+- Execute commands on demand with the `--commands` mode
 - Plays nice with node.js command line flags like `--inspect` or `--prof`
 - Produces sourcemaps which Just Work™️ by default for debugging with many editors (VSCode, IntelliJ, etc)
 - Monorepo aware, allowing for different configuration per package and only compiling what is actually required from the monorepo context

src/Options.ts

@@ -7,7 +7,6 @@ export interface RunOptions {
   argv: string[];
   terminalCommands: boolean;
   reloadOnChanges: boolean;
-  supervise: boolean;
   useEsbuild: boolean;
 }
 

src/Supervisor.ts

@@ -46,7 +46,7 @@ export class Supervisor extends EventEmitter {
 
     this.process.on("message", (value) => this.emit("message", value));
     this.process.on("exit", (code, signal) => {
-      if (signal !== "SIGKILL" && this.options.supervise) {
+      if (signal !== "SIGKILL") {
         log.warn(`process exited with ${code}`);
       }
     });

src/bench/bench.ts

@@ -36,11 +36,10 @@ function monitorLogs(childProcess: ChildProcess): Promise<ChildProcessResult> {
   });
 }
 
-function spawnOnce(args: { supervise?: boolean; filename: string; esbuild: boolean }): ChildProcess {
+function spawnOnce(args: { watch?: boolean; filename: string; esbuild: boolean }): ChildProcess {
   const extraArgs = [];
 
-  if (args.supervise) {
-    extraArgs.push("--supervise");
+  if (args.watch) {
     extraArgs.push("--watch");
   }
 
@@ -158,7 +157,7 @@ export async function benchReload(args: BenchArgs): Promise<void> {
 
   process.stdout.write(`Starting reload benchmark (pid=${process.pid})\n`);
 
-  const childProcess = spawnOnce({ supervise: true, filename: filepath, esbuild: args.esbuild });
+  const childProcess = spawnOnce({ watch: true, filename: filepath, esbuild: args.esbuild });
   const _ignoreInitialBoot = await monitorLogs(childProcess);
 
   for (let i = 0; i < args.runs; i++) {

src/index.ts

@@ -33,12 +33,6 @@ export const cli = async () => {
       description: "Trigger restarts by watching for changes to required files",
       default: true,
     })
-    .option("supervise", {
-      alias: "s",
-      type: "boolean",
-      description: "Supervise and restart the process when it exits indefinitely",
-      default: false,
-    })
     .option("esbuild", {
       type: "boolean",
       description: "Use esbuild instead of sec",
@@ -49,7 +43,6 @@ export const cli = async () => {
     argv: args._ as any,
     terminalCommands: args.commands,
     reloadOnChanges: args.watch,
-    supervise: args.supervise,
     useEsbuild: args.esbuild,
   });
 };
@@ -157,7 +150,7 @@ export const wds = async (options: RunOptions) => {
   await startIPCServer(serverSocketPath, project);
 
   // kickoff the first child process
-  options.supervise && log.info(`Supervision starting for command: node ${options.argv.join(" ")}`);
+  options.reloadOnChanges && log.info(`Supervision starting for command: node ${options.argv.join(" ")}`);
   await project.invalidateBuildSetAndReload();
 
   process.on("SIGINT", () => {
@@ -170,9 +163,14 @@ export const wds = async (options: RunOptions) => {
   });
 
   project.supervisor.process.on("exit", (code) => {
-    log.debug(`child process exited with code ${code}, ${options.supervise ? "not exiting because supervise mode" : "exiting..."}`);
-    if (!options.supervise) {
-      project.shutdown(code ?? 1);
+    const logShutdown = (explanation: string) => {
+      log.debug(`child process exited with code ${code}, ${explanation}`);
+    };
+    if (options.reloadOnChanges) {
+      logShutdown("not exiting because we're on 'watch' mode");
+      return;
     }
+    logShutdown("shutting down project since it's no longer needed...");
+    project.shutdown(code ?? 1);
   });
 };

test/reload/test.sh

@@ -9,12 +9,12 @@ trap "kill -9 0" INT TERM
 trap 'kill $(jobs -p)' EXIT
 
 # run a server in the background
-$DIR/../../pkg/wds.bin.js $@ --supervise --commands $DIR/run-scratch.ts &
+$DIR/../../pkg/wds.bin.js $@ --commands $DIR/run-scratch.ts &
 
 max_retry=5
 counter=0
 
-set +e 
+set +e
 until curl -s localhost:8080 | grep "World"
 do
    sleep 1
@@ -39,4 +39,4 @@ done
 
 echo "Made new request to reloaded server"
 
-exit 0
+exit 0