feat: run & restart

Author: Jan Krems

examples/three-lines.js

@@ -0,0 +1,4 @@
+'use strict';
+let x = 1;
+x = x + 1;
+module.exports = x;

lib/internal/inspect-protocol.js

@@ -213,6 +213,10 @@ class Client extends EventEmitter {
 
   callMethod(method, params) {
     return new Promise((resolve, reject) => {
+      if (!this._socket) {
+        reject(new Error('Use `run` to start the app again.'));
+        return;
+      }
       const data = { id: ++this._lastId, method, params };
       this._pending[data.id] = (error, result) => {
         if (error) reject(unpackError(error));
@@ -257,6 +261,9 @@ class Client extends EventEmitter {
 
       this._socket = socket;
       socket.on('data', this.handleChunk);
+      socket.on('close', () => {
+        this.emit('close');
+      });
 
       Promise.all([
         this.callMethod('Runtime.enable'),

lib/internal/inspect-repl.js

@@ -199,13 +199,26 @@ function createRepl(inspector) {
   let repl; // eslint-disable-line prefer-const
   let lastCommand;
 
+  // Things we want to keep around
   const history = { control: [], debug: [] };
-  const knownScripts = {};
   const watchedExpressions = [];
   const knownBreakpoints = [];
 
+  // Things we need to reset when the app restarts
+  let knownScripts;
   let currentBacktrace;
   let selectedFrame;
+  let exitDebugRepl;
+
+  function resetOnStart() {
+    knownScripts = {};
+    currentBacktrace = null;
+    selectedFrame = null;
+
+    if (exitDebugRepl) exitDebugRepl();
+    exitDebugRepl = null;
+  }
+  resetOnStart();
 
   const print = inspector.print.bind(inspector);
 
@@ -594,6 +607,14 @@ function createRepl(inspector) {
 
   function initializeContext(context) {
     copyOwnProperties(context, {
+      get run() {
+        return inspector.run();
+      },
+
+      get restart() {
+        return inspector.run();
+      },
+
       get cont() {
         handleResumed();
         return Debugger.resume();
@@ -654,7 +675,7 @@ function createRepl(inspector) {
 
         const oldContext = repl.context;
 
-        function exitDebugRepl() {
+        exitDebugRepl = () => {
           // Restore all listeners
           process.nextTick(() => {
             listeners.forEach((listener) => {
@@ -675,7 +696,9 @@ function createRepl(inspector) {
 
           repl.rli.removeListener('SIGINT', exitDebugRepl);
           repl.removeListener('exit', exitDebugRepl);
-        }
+
+          exitDebugRepl = null;
+        };
 
         // Exit debug repl on SIGINT
         repl.rli.on('SIGINT', exitDebugRepl);
@@ -733,6 +756,14 @@ function createRepl(inspector) {
       repl.rli.emit('SIGINT');
     });
 
+    inspector.client.on('close', () => {
+      resetOnStart();
+    });
+
+    inspector.client.on('ready', () => {
+      // TODO: restore breakpoints
+    });
+
     return repl;
   };
 }

lib/node-inspect.js

@@ -200,6 +200,9 @@ class NodeInspector {
     if (!this.paused) {
       this.repl.displayPrompt(true);
     }
+    if (/Waiting for the debugger to disconnect\.\.\.\n$/.test(text)) {
+      this.killChild();
+    }
   }
 }
 

test/cli/launch.test.js

@@ -27,3 +27,49 @@ test('examples/empty.js', (t) => {
       t.equal(code, 0, 'exits with success');
     });
 });
+
+test('run after quit / restart', (t) => {
+  const cli = startCLI(['examples/three-lines.js']);
+
+  function onFatal(error) {
+    cli.quit();
+    throw error;
+  }
+
+  return cli.waitFor(/break/)
+    .then(() => cli.waitForPrompt())
+    .then(() => cli.stepCommand('n'))
+    .then(() => {
+      t.match(cli.output, 'break in examples/three-lines.js:2',
+        'steps to the 2nd line');
+    })
+    .then(() => cli.command('cont'))
+    .then(() => cli.waitFor(/disconnect/))
+    .then(() => {
+      t.match(cli.output, 'Waiting for the debugger to disconnect',
+        'the child was done');
+    })
+    .then(() => cli.command('cont'))
+    .then(() => cli.waitFor(/start the app/))
+    .then(() => {
+      t.match(cli.output, 'Use `run` to start the app again');
+    })
+    .then(() => cli.stepCommand('run'))
+    .then(() => cli.waitForPrompt())
+    .then(() => {
+      t.match(cli.output, 'break in examples/three-lines.js:1',
+        'is back at the beginning');
+    })
+    .then(() => cli.stepCommand('n'))
+    .then(() => {
+      t.match(cli.output, 'break in examples/three-lines.js:2',
+        'steps to the 2nd line');
+    })
+    .then(() => cli.stepCommand('restart'))
+    .then(() => {
+      t.match(cli.output, 'break in examples/three-lines.js:1',
+        'is back at the beginning');
+    })
+    .then(() => cli.quit())
+    .then(null, onFatal);
+});