From b5aed43f04b50b2e21bf2c370b859f9b8fbd0270 Mon Sep 17 00:00:00 2001
From: Ryan Dahl <ry@tinyclouds.org>
Date: Wed, 22 Dec 2010 18:30:56 -0800
Subject: [PATCH] Add better breakpoint text

---
 lib/_debugger.js | 145 ++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 119 insertions(+), 26 deletions(-)

diff --git a/lib/_debugger.js b/lib/_debugger.js
index 83bc6c8fba0..d1920943ae4 100644
--- a/lib/_debugger.js
+++ b/lib/_debugger.js
@@ -142,7 +142,10 @@ Client.prototype._onResponse = function(res) {
 
   if (res.headers.Type == 'connect') {
     // do nothing
+    console.log(res);
     this.emit('ready');
+  } else if (res.body && res.body.event == 'break') {
+    this.emit('break', res.body);
   } else if (cb) {
     this._reqCallbacks.splice(i, 1);
     cb(res.body);
@@ -214,33 +217,76 @@ Client.prototype.reqScripts = function(cb) {
 
 Client.prototype.reqContinue = function(cb) {
   this.req({ command: 'continue' } , function (res) {
-    if (cb) cb(res.body);
+    if (cb) cb(res);
   });
 };
 
 
 var helpMessage = "Commands: scripts, backtrace, version, eval, help, quit";
 
+function SourceUnderline(source_text, position) {
+  if (!source_text) {
+    return;
+  }
+
+  // Create an underline with a caret pointing to the source position. If the
+  // source contains a tab character the underline will have a tab character in
+  // the same place otherwise the underline will have a space character.
+  var underline = '';
+  for (var i = 0; i < position; i++) {
+    if (source_text[i] == '\t') {
+      underline += '\t';
+    } else {
+      underline += ' ';
+    }
+  }
+  underline += '^';
+
+  // Return the source line text with the underline beneath.
+  return source_text + '\n' + underline;
+}
+
+function SourceInfo(body) {
+  var result = '';
+
+  if (body.script) {
+    if (body.script.name) {
+      result += body.script.name;
+    } else {
+      result += '[unnamed]';
+    }
+  }
+  result += ' line ';
+  result += body.sourceLine + 1;
+  result += ' column ';
+  result += body.sourceColumn + 1;
+
+  return result;
+}
+
+
+
+
 
 function startInterface() {
 
-  var i = readline.createInterface(process.stdout);
+  var term = readline.createInterface(process.stdout);
   var stdin = process.openStdin();
   stdin.addListener('data', function(chunk) {
-    i.write(chunk);
+    term.write(chunk);
   });
 
   var prompt = 'debug> ';
 
-  i.setPrompt(prompt);
-  i.prompt();
+  term.setPrompt('debug> ');
+  term.prompt();
 
   var quitTried = false;
 
   function tryQuit() {
     if (quitTried) return;
     quitTried = true;
-    i.close();
+    term.close();
     console.log("debug done\n");
     if (c.writable) {
       c.reqContinue(function (res) {
@@ -251,45 +297,64 @@ function startInterface() {
     }
   }
 
-  i.on('SIGINT', tryQuit);
-  i.on('close', tryQuit);
+  term.on('SIGINT', tryQuit);
+  term.on('close', tryQuit);
+  c.on('close', function () {
+    process.exit(0);
+  });
 
-  i.on('line', function(cmd) {
+  term.on('line', function(cmd) {
     if (cmd == 'quit') {
       tryQuit();
     } else if (/^help/.test(cmd)) {
       console.log(helpMessage);
-      i.prompt();
+      term.prompt();
 
     } else if ('version' == cmd) {
       c.reqVersion(function (v) {
         console.log(v);
-        i.prompt();
+        term.prompt();
       });
 
-    } else if ('backtrace' == cmd || 'bt' == cmd) {
+    } else if (/^backtrace/.test(cmd) || /^bt/.test(cmd)) {
       c.reqBacktrace(function (bt) {
-        console.log(bt);
-        i.prompt();
+        if (/full/.test(cmd)) {
+          console.log(bt);
+        } else if (bt.totalFrames == 0) {
+          console.log('(empty stack)');
+        } else {
+          var result = 'Frames #' + bt.fromFrame +
+                       ' to #' + (bt.toFrame - 1) +
+                       ' of ' + bt.totalFrames + '\n';
+          for (j = 0; j < bt.frames.length; j++) {
+            if (j != 0) result += '\n';
+            result += bt.frames[j].text;
+          }
+          console.log(result);
+        }
+        term.prompt();
       });
 
-    } else if ('continue' == cmd || 'c' == cmd) {
+    } else if (/^continue/.test(cmd) || /^c/.test(cmd)) {
       c.reqContinue(function (res) {
-        console.log(res);
-        i.prompt();
+         // Wait for break point. (disable raw mode?)
       });
 
     } else if (/^scripts/.test(cmd)) {
       c.reqScripts(function (res) {
-        var text = res.map(function (x) { return x.text; });
-        console.log(text.join('\n'));
-        i.prompt();
+        if (/full/.test(cmd)) {
+          console.log(res);
+        } else {
+          var text = res.map(function (x) { return x.text; });
+          console.log(text.join('\n'));
+        }
+        term.prompt();
       });
 
     } else if (/^eval/.test(cmd)) {
       c.reqEval(cmd.slice(5), function (res) {
         console.log(res);
-        i.prompt();
+        term.prompt();
       });
 
     } else {
@@ -297,17 +362,45 @@ function startInterface() {
         // If it's not all white-space print this error message.
         console.log('Unknown command "%s". Try "help"', cmd);
       }
-      i.prompt();
+      term.prompt();
     }
   });
 
   c.on('unhandledResponse', function (res) {
     console.log("\r\nunhandled res:");
-    console.log(res.body);
-    i.prompt();
+    console.log(res);
+    term.prompt();
   });
 
-  i.on('close', function() {
-    stdin.destroy();
+  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;
+
+    console.log(result);
+
+    term.prompt();
   });
 }