From d4859a55bc8f18f1834546af12a8d8f6a8802ebd Mon Sep 17 00:00:00 2001
From: Ryan Dahl <ry@tinyclouds.org>
Date: Thu, 30 Dec 2010 11:17:11 -0800
Subject: [PATCH] Wrap up debugger in one class

just for better readablity
---
 lib/_debugger.js | 526 +++++++++++++++++++++++++++++--------------------------
 1 file changed, 279 insertions(+), 247 deletions(-)

diff --git a/lib/_debugger.js b/lib/_debugger.js
index 07a02cc..e0bd3e1 100644
--- a/lib/_debugger.js
+++ b/lib/_debugger.js
@@ -6,96 +6,14 @@ var spawn = require('child_process').spawn;
 exports.port = 5858;
 
 exports.start = function () {
-  startInterface();
-
-  process.on('exit', function () {
-    if (child) child.kill();
-  });
+  var interface = new Interface();
 };
 
-var child;
-var c;
-var term;
+
 var args = process.argv.slice(2);
 args.unshift('--debug-brk');
 
 
-function tryConnect(cb) {
-  c = new Client();
-
-  process.stdout.write("connecting...");
-  c.connect(exports.port);
-  c.once('ready', function () {
-    process.stdout.write("ok\r\n");
-    if (cb) cb();
-  });
-
-  c.on('close', function () {
-    process.exit(0);
-  });
-
-  c.on('unhandledResponse', function (res) {
-    console.log("\r\nunhandled res:");
-    console.log(res);
-    term.prompt();
-  });
-
-  c.on('break', function (res) {
-    var result = '';
-    if (res.body.breakpoints) {
-      result += 'breakpoint';
-      if (res.body.breakpoints.length > 1) {
-        result += 's';
-      }
-      result += ' #';
-      for (var i = 0; i < res.body.breakpoints.length; i++) {
-        if (i > 0) {
-          result += ', #';
-        }
-        result += res.body.breakpoints[i];
-      }
-    } else {
-      result += 'break';
-    }
-    result += ' in ';
-    result += res.body.invocationText;
-    result += ', ';
-    result += SourceInfo(res.body);
-    result += '\n';
-    result += SourceUnderline(res.body.sourceLineText, res.body.sourceColumn);
-
-    c.currentSourceLine = res.body.sourceLine;
-    c.currentFrame = 0;
-    c.currentScript = res.body.script.name;
-
-    console.log(result);
-
-    term.prompt();
-  });
-}
-
-
-function killChild() {
-  if (c) {
-    c.destroy();
-  }
-
-  if (child) {
-    child.kill();
-    child = null;
-  }
-}
-
-
-function trySpawn(cb) {
-  killChild();
-
-  child = spawn(process.execPath, args, { customFds: [0, 1, 2] });
-
-  setTimeout(function () {
-    tryConnect(cb);
-  }, 1000);
-}
 
 //
 // Parser/Serializer for V8 debugger protocol
@@ -185,7 +103,7 @@ var NO_FRAME = -1;
 
 function Client() {
   net.Stream.call(this);
-  var protocol = this.protocol = new Protocol(c);
+  var protocol = this.protocol = new Protocol(this);
   this._reqCallbacks = [];
   var socket = this;
 
@@ -340,7 +258,7 @@ Client.prototype.listbreakpoints = function(cb) {
   });
 };
 
-// c.next(1, cb);
+// client.next(1, cb);
 Client.prototype.step = function(action, count, cb) {
   var req = {
     command: 'continue',
@@ -394,202 +312,316 @@ function SourceInfo(body) {
 }
 
 
-var restartQuestionPrompt = "The program being debugged has " +
-                            "been started already.\n" +
-                            "Start it from the beginning? (y or n): ";
+// This class is the readline-enabled debugger interface which is invoked on
+// "node debug"
+function Interface() {
+  var self = this;
+  var term = this.term = readline.createInterface(process.stdout);
+  var child;
+  var client;
+  var term;
 
-function restartQuestion (cb) {
-  term.question(restartQuestionPrompt, function (answer) {
-    if (/^y(es)?$/i.test(answer)) {
-      cb(true);
-    } else if (/^n(o)?$/i.test(answer)) {
-      cb(false);
-    } else {
-      console.log("Please answer y or n.");
-      restartQuestion(cb);
-    }
+  process.on('exit', function () {
+    self.killChild();
   });
-}
-
-
-function printScripts () {
-  var text = '';
-  for (var id in c.scripts) {
-    var script = c.scripts[id];
-    if (typeof script == 'object' && script.name) {
-      text += script.name == c.currentScript ? '* ' : '  ';
-      text += script.name + '\n';
-    }
-  }
-  process.stdout.write(text);
-}
-
-
-function printNotConnected () {
-  console.log("Program not running. Try 'run'.");
-  term.prompt();
-}
-
-
-function startInterface() {
-
-  term = readline.createInterface(process.stdout);
 
   var stdin = process.openStdin();
   stdin.addListener('data', function(chunk) {
     term.write(chunk);
   });
 
-  var prompt = 'debug> ';
-
   term.setPrompt('debug> ');
   term.prompt();
 
-  var quitTried = false;
+  this.quitTried = false;
+
+
+  term.on('SIGINT', function () {
+    self.tryQuit();
+  });
 
-  function tryQuit() {
-    if (quitTried) return;
-    quitTried = true;
-    killChild();
-    term.close();
-    process.exit(0);
-  }
 
-  term.on('SIGINT', tryQuit);
-  term.on('close', tryQuit);
+  term.on('close', function () {
+    self.tryQuit();
+  });
 
   term.on('line', function(cmd) {
+
     // trim whitespace
     cmd = cmd.replace(/^\s*/, '').replace(/\s*$/, '');
+    self.handleCommand(cmd);
+  });
+}
 
-    if (cmd == 'quit' || cmd == 'q' || cmd == 'exit') {
-      tryQuit();
-
-    } else if (/^r(un)?/.test(cmd)) {
-      if (child) {
-        restartQuestion(function (yes) {
-          if (!yes) {
-            term.prompt();
-          } else {
-            console.log("restarting...");
-            trySpawn(function () {
-              c.reqContinue();
-            });
-          }
-        });
-      } else {
-        trySpawn(function () {
-          c.reqContinue();
-        });
-      }
 
-    } else if (/^help/.test(cmd)) {
-      console.log(helpMessage);
-      term.prompt();
+Interface.prototype.tryQuit = function() {
+  if (this.quitTried) return;
+  this.quitTried = true;
+  this.killChild();
+  this.term.close();
+  process.exit(0);
+};
 
-    } else if ('version' == cmd) {
-      if (!c) {
-        printNotConnected();
-        return;
-      }
-      c.reqVersion(function (v) {
-        console.log(v);
-        term.prompt();
-      });
 
-    } else if (/info +breakpoints/.test(cmd)) {
-      if (!c) {
-        printNotConnected();
-        return;
+Interface.prototype.handleBreak = function(r) {
+  var result = '';
+  if (r.breakpoints) {
+    result += 'breakpoint';
+    if (r.breakpoints.length > 1) {
+      result += 's';
+    }
+    result += ' #';
+    for (var i = 0; i < r.breakpoints.length; i++) {
+      if (i > 0) {
+        result += ', #';
       }
-      c.listbreakpoints(function (res) {
-        console.log(res);
-        term.prompt();
-      });
+      result += r.breakpoints[i];
+    }
+  } else {
+    result += 'break';
+  }
+  result += ' in ';
+  result += r.invocationText;
+  result += ', ';
+  result += SourceInfo(r);
+  result += '\n';
+  result += SourceUnderline(r.sourceLineText, r.sourceColumn);
 
-    } else if (/^backtrace/.test(cmd) || /^bt/.test(cmd)) {
-      if (!c) {
-        printNotConnected();
-        return;
-      }
-      c.reqBacktrace(function (bt) {
-        if (/full/.test(cmd)) {
-          console.log(bt);
-        } else if (bt.totalFrames == 0) {
-          console.log('(empty stack)');
+  this.client.currentSourceLine = r.sourceLine;
+  this.client.currentFrame = 0;
+  this.client.currentScript = r.script.name;
+
+  console.log(result);
+
+  this.term.prompt();
+};
+
+
+Interface.prototype.handleCommand = function(cmd) {
+  var self = this;
+
+  var client = this.client;
+  var term = this.term;
+
+  if (cmd == 'quit' || cmd == 'q' || cmd == 'exit') {
+    self.tryQuit();
+
+  } else if (/^r(un)?/.test(cmd)) {
+    if (self.child) {
+      self.restartQuestion(function (yes) {
+        if (!yes) {
+          term.prompt();
         } else {
-          var result = '';
-          for (j = 0; j < bt.frames.length; j++) {
-            if (j != 0) result += '\n';
-            result += bt.frames[j].text;
-          }
-          console.log(result);
+          console.log("restarting...");
+          self.trySpawn();
         }
-        term.prompt();
       });
+    } else {
+      self.trySpawn();
+    }
 
-    } else if (cmd == 'scripts' || cmd == 'scripts full') {
-      if (!c) {
-        printNotConnected();
-        return;
-      }
-      printScripts();
+  } else if (/^help/.test(cmd)) {
+    console.log(helpMessage);
+    term.prompt();
+
+  } else if ('version' == cmd) {
+    if (!client) {
+      self.printNotConnected();
+      return;
+    }
+    client.reqVersion(function (v) {
+      console.log(v);
       term.prompt();
+    });
 
-    } else if (/^continue/.test(cmd) || /^c/.test(cmd)) {
-      if (!c) {
-        printNotConnected();
-        return;
-      }
-      c.reqContinue(function (res) {
-        // Wait for break point. (disable raw mode?)
-      });
+  } else if (/info +breakpoints/.test(cmd)) {
+    if (!client) {
+      self.printNotConnected();
+      return;
+    }
+    client.listbreakpoints(function (res) {
+      console.log(res);
+      term.prompt();
+    });
 
-    } else if (/^next/.test(cmd) || /^n/.test(cmd)) {
-      if (!c) {
-        printNotConnected();
-        return;
+  } else if (/^backtrace/.test(cmd) || /^bt/.test(cmd)) {
+    if (!client) {
+      self.printNotConnected();
+      return;
+    }
+    client.reqBacktrace(function (bt) {
+      if (/full/.test(cmd)) {
+        console.log(bt);
+      } else if (bt.totalFrames == 0) {
+        console.log('(empty stack)');
+      } else {
+        var result = '';
+        for (j = 0; j < bt.frames.length; j++) {
+          if (j != 0) result += '\n';
+          result += bt.frames[j].text;
+        }
+        console.log(result);
       }
-      c.step('next', 1, function (res) {
-        // Wait for break point. (disable raw mode?)
-      });
+      term.prompt();
+    });
 
-    } else if (/^step/.test(cmd) || /^s/.test(cmd)) {
-      if (!c) {
-        printNotConnected();
-        return;
-      }
-      c.step('in', 1, function (res) {
-        // Wait for break point. (disable raw mode?)
-      });
+  } else if (cmd == 'scripts' || cmd == 'scripts full') {
+    if (!client) {
+      self.printNotConnected();
+      return;
+    }
+    self.printScripts();
+    term.prompt();
 
-    } else if (/^print/.test(cmd) || /^p/.test(cmd)) {
-      if (!c) {
-        printNotConnected();
-        return;
-      }
-      var i = cmd.indexOf(' ');
-      if (i < 0) {
-        console.log("print [expression]");
+  } else if (/^c(ontinue)?/.test(cmd)) {
+    if (!client) {
+      self.printNotConnected();
+      return;
+    }
+    client.reqContinue(function (res) {
+      // Wait for break point. (disable raw mode?)
+    });
+
+  } else if (/^next/.test(cmd) || /^n/.test(cmd)) {
+    if (!client) {
+      self.printNotConnected();
+      return;
+    }
+    client.step('next', 1, function (res) {
+      // Wait for break point. (disable raw mode?)
+    });
+
+  } else if (/^step/.test(cmd) || /^s/.test(cmd)) {
+    if (!client) {
+      self.printNotConnected();
+      return;
+    }
+    client.step('in', 1, function (res) {
+      // Wait for break point. (disable raw mode?)
+    });
+
+  } else if (/^print/.test(cmd) || /^p/.test(cmd)) {
+    if (!client) {
+      self.printNotConnected();
+      return;
+    }
+    var i = cmd.indexOf(' ');
+    if (i < 0) {
+      console.log("print [expression]");
+      term.prompt();
+    } else {
+      cmd = cmd.slice(i);
+      client.reqEval(cmd, function (res) {
+        if (res) {
+          console.log(res.text);
+        } else {
+          console.log(res);
+        }
         term.prompt();
-      } else {
-        cmd = cmd.slice(i);
-        c.reqEval(cmd, function (res) {
-          if (res) {
-            console.log(res.text);
-          } else {
-            console.log(res);
-          }
-          term.prompt();
-        });
-      }
+      });
+    }
+
+  } else {
+    if (!/^\s*$/.test(cmd)) {
+      // If it's not all white-space print this error message.
+      console.log('Unknown command "%s". Try "help"', cmd);
+    }
+    term.prompt();
+  }
+};
+
+
+var restartQuestionPrompt = "The program being debugged has " +
+                            "been started already.\n" +
+                            "Start it from the beginning? (y or n): ";
 
+Interface.prototype.restartQuestion = function(cb) {
+  var self = this;
+  this.term.question(restartQuestionPrompt, function (answer) {
+    if (/^y(es)?$/i.test(answer)) {
+      cb(true);
+    } else if (/^n(o)?$/i.test(answer)) {
+      cb(false);
     } else {
-      if (!/^\s*$/.test(cmd)) {
-        // If it's not all white-space print this error message.
-        console.log('Unknown command "%s". Try "help"', cmd);
-      }
-      term.prompt();
+      console.log("Please answer y or n.");
+      self.restartQuestion(cb);
     }
   });
-}
+};
+
+
+Interface.prototype.killChild = function() {
+  if (this.client) {
+    this.client.destroy();
+    this.client = null;
+  }
+
+  if (this.child) {
+    this.child.kill();
+    this.child = null;
+  }
+};
+
+
+Interface.prototype.trySpawn = function(cb) {
+  this.killChild();
+
+  this.child = spawn(process.execPath, args, { customFds: [0, 1, 2] });
+
+  var self = this;
+  setTimeout(function () {
+    process.stdout.write("connecting...");
+    var client = self.client = new Client();
+    client.connect(exports.port);
+
+    client.once('ready', function () {
+      process.stdout.write("ok\r\n");
+
+      // since we did debug-brk, we're hitting a break point immediately
+      // continue before anything else.
+      client.reqContinue();
+
+      if (cb) cb();
+    });
+
+    client.on('close', function () {
+      console.log("\nprogram terminated");
+      self.client = null;
+      self.killChild();
+      self.term.prompt();
+    });
+
+    client.on('unhandledResponse', function (res) {
+      console.log("\r\nunhandled res:");
+      console.log(res);
+      self.term.prompt();
+    });
+
+    client.on('break', function (res) {
+      self.handleBreak(res.body);
+    });
+  }, 100);
+};
+
+
+Interface.prototype.printNotConnected = function() {
+  console.log("Program not running. Try 'run'.");
+  this.term.prompt();
+};
+
+
+Interface.prototype.printScripts = function() {
+  var client = this.client;
+  var text = '';
+  for (var id in client.scripts) {
+    var script = client.scripts[id];
+    if (typeof script == 'object' && script.name) {
+      text += script.name == client.currentScript ? '* ' : '  ';
+      text += script.name + '\n';
+    }
+  }
+  process.stdout.write(text);
+};
+
+
+
-- 
2.7.4