1 files changed, 86 insertions, 0 deletions
diff --git a/toolkit/jetpack/sdk/console/traceback.js b/toolkit/jetpack/sdk/console/traceback.js
new file mode 100644
index 000000000..be0fb7b94
--- /dev/null
+++ b/toolkit/jetpack/sdk/console/traceback.js
@@ -0,0 +1,86 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+"use strict";
+
+module.metadata = {
+  "stability": "experimental"
+};
+
+const { Ci, components } = require("chrome");
+const { parseStack, sourceURI } = require("toolkit/loader");
+const { readURISync } = require("../net/url");
+
+function safeGetFileLine(path, line) {
+  try {
+    var scheme = require("../url").URL(path).scheme;
+    // TODO: There should be an easier, more accurate way to figure out
+    // what's the case here.
+    if (!(scheme == "http" || scheme == "https"))
+      return readURISync(path).split("\n")[line - 1];
+  } catch (e) {}
+  return null;
+}
+
+function nsIStackFramesToJSON(frame) {
+  var stack = [];
+
+  while (frame) {
+    if (frame.filename) {
+      stack.unshift({
+        fileName: sourceURI(frame.filename),
+        lineNumber: frame.lineNumber,
+        name: frame.name
+      });
+    }
+    frame = frame.caller;
+  }
+
+  return stack;
+};
+
+var fromException = exports.fromException = function fromException(e) {
+  if (e instanceof Ci.nsIException)
+    return nsIStackFramesToJSON(e.location);
+  if (e.stack && e.stack.length)
+    return parseStack(e.stack);
+  if (e.fileName && typeof(e.lineNumber == "number"))
+    return [{fileName: sourceURI(e.fileName),
+             lineNumber: e.lineNumber,
+             name: null}];
+  return [];
+};
+
+var get = exports.get = function get() {
+  return nsIStackFramesToJSON(components.stack.caller);
+};
+
+var format = exports.format = function format(tbOrException) {
+  if (tbOrException === undefined) {
+    tbOrException = get();
+    tbOrException.pop();
+  }
+
+  var tb;
+  if (typeof(tbOrException) == "object" &&
+      tbOrException.constructor.name == "Array")
+    tb = tbOrException;
+  else
+    tb = fromException(tbOrException);
+
+  var lines = ["Traceback (most recent call last):"];
+
+  tb.forEach(
+    function(frame) {
+      if (!(frame.fileName || frame.lineNumber || frame.name))
+      	return;
+
+      lines.push('  File "' + frame.fileName + '", line ' +
+                 frame.lineNumber + ', in ' + frame.name);
+      var sourceLine = safeGetFileLine(frame.fileName, frame.lineNumber);
+      if (sourceLine)
+        lines.push('    ' + sourceLine.trim());
+    });
+
+  return lines.join("\n");
+};