Script Panel Refactoring

From FirebugWiki

This page summarizes refactoring the Firebug debugger to use JSD2 and adding support for remote JavaScript debugging. Issue 5421 tracks the actual changes done.

Contents 1 Goals 2 Resources 3 Related Issues 4 JSD2 API Requirements 4.1 Not Ready in JSD2 5 Script Panel Architecture

Goals

• Adopt JSD2 (get rid of all JSD1 APIs)
• Support remote debugging

Resources

Firebug Wiki:

• HTTP Monitor
• Firebug 1.7 BTI
• Net Panel Architecture Review

Mozilla Wiki:

• Debugger
• Debugger Client API
• JS Debugger API Guide
• JS Debugger API Reference
• DevTools Debugger
• Remote Debugging Protocol

Related Issues

• Issue 5421: Implement JSD2

JSD2 API Requirements

The following list summarizes the high-level features that Firebug needs to support. It should be verified that all the features can re-implemented on top of JSD2 before starting the refactoring.

• List of scripts available on selected tab (including static, events and evaluated scripts) including iframes → Debugger.findScripts()
• Stepping (into, over, out, resume, current line)
• Support for debugger; keyword → Debugger.onDebuggerStatement()
• Support for breakpoints (add, remove, enable, disabled, conditional, list of existing breakpoints) → Debugger.Script methods
• Recognize executable lines
• Dynamic eval in a frame (used e.g. by the Watch Side Panel when the debugger is halted) → Debugger.Frame.eval() and Debugger.Frame.evalWithBindings()
• Get stack frames (including passed arguments) → Debugger.getNewestFrame() and Debugger.Frame.older
• Scope chain variable exploring (with & closure scopes). It should be possible to see all values. → Debugger.Frame.environment
• Break on next call
• Profiling (was part of JSD1)
• Tracking (break on) throw/catch/error → Debugger.onThrow() and Debugger.onError()
• Tracking (monitoring) function calls
• Freezing page UI if debugger is halted (including timeouts, intervals and worker threads)

Not Ready in JSD2

• There is not source for evals.
• new Function scripts?
• Meta bug: Implement a script Debugger
  • As soon as this one is fixed
  • Profiling is unrelated to JSD2. What is the plan here?
  • Tracking (break on) throw/catch/error; also what is the plan?
• Conditional breakpoints (bug 740825)

Script Panel Architecture

The Script panel needs to be built on top of JSD2, remote protocol and Firebug remote architecture. Remoting is already supported by HTTP Monitor and both components should share the same approaches and API.

TBD