source maps Yury completed a prototype of scope and variable mapping. The proof of concept maps let and const variables from the generated scope into original scopes. This builds on the work to map minified variables where original variable names and original variable names are swapped at runtime. We think that we will be able to cover additional cases in 2018 so that users see the original variable names and values when they're paused! pretty printing Assaf hacked on pretty printing last week and it's now much better! The debugger now auto-pretty-prints minified sources. We'll have a preference for disabling it next week. Debugger also upgraded acorn, which has support for pretty printing template strings.

performance This week we landed the architectural performance work, which lets the debugger UI show initial pause data like pause line and frames, before fetching scopes and re-mapping locations.

We also landed a similar optimization where we no longer try to parse and traverse the files before showing the source text. Previously, the parser would block for up to 10 seconds while parsing large files. Yikes!

code health This week was a big week for code health. We upgraded to flow 57, added license headers to all of our files, and switched to using object spread universally.

Also, in an effort to reduce our bundle size, we dropped react-immutable-proptypes and stopped using devtools-launchpad for showing context menus. We're now using the launchpad in just one spot and should be able to remove it soon. When we do, the bundle size will get 20% smaller!

preview* We landed 3 big fixes for preview this week. The craziest bug was an issue, which Ted Campbell filed, 6 weeks ago where clicking a link in the scopes pane would literally navigate you away from the debugger and to the page as opposed to opening a new tab. This of course is terrible, because the debugger is NOT a browser.

Another, important fix was with showing local scopes. Jim blandy fixed a bug, which was introduced in August where the frame finished variables like return and thrown were no longer being shown. We now have unit test and integration test coverage to catch this in the future! The tests are really great too :)

The last item, is more of a fun feature than anything else. But because we parse the original source text with babel, it was possible that you could hover on a function param, which has a flow type. Previously we would highlight the type as well, but now we're smarter and just highlight the param. Check out a video of how Jason fixed it!

• we started optimistically clearing the pause state when we step, which eagerly clears the UI and prepares it for another step. We also defer fetching and mapping scopes when the debugger pauses, which makes the UI a bit snappier.
• We devoted some of our time to improving our airtable config. Airtable will allow us to better manage our open source work / github progress, as well as give us faster access to what has happened over the past week.
• The biggest fix we had this week was done by @nyrosmith, who noticed that our breakpoints were not responding when the page was reloaded. This turned out to be an issue with how breakpoints were being synced, and could have been avoided if we were stricter with our types!

• Wellington unified our search UX to create an editor style modal for searching for files, functions, variables, and jumping to a line. We now have helpful prefixes for changing modes: @, #, :.
• Lots of great UI polish
• Sped up stepping with large files

This week we had 25 contributors and 30+ PRs.

• Andrew helped us upgrade to flow 53
• Jiel helped us convert SVGs to background images
• Tohm blackboxed sources are now identified in the source tree
• Sneha Aligned the first tab with wide gutters
• Bomsy and James got jump to line to support scrolling to columns.

• New Go to line Modal, allowing users to go to a specific line in an open file
• Showing react classes in preview
• Improvements to the source tree panel including
  • Setting a root folder
  • Collapsing all nodes
• we managed a substantial refactoring of our editor, making it more modular and easy to work with for developers
• new docs were added regarding triaging and merge conflicts

• UCOSP Students
• UX/UI
• Shortcuts
• Preview
• Outline View
• Photon
• Project Search
• Watch Expressions
• Context Menu
• Map Minified variables
• List Workers
• Accessibility
• Breakpoints
• Infrastructure
• Performance

• AST Breakpoints landed the final changes for finding a breakpoint ast location and setting an ast location when a breakpoint is created. We should be able to land AST Breakpoints this week!
• Async Stepping landed the utilities for identifying async expressions, and the logical "next" statement to step to. Async Stepping will land in the next release.
• WASM We enabled wasm debugging in the new UI and it is now turned on in nightly. Debugging WASM source code in the native language (C, C++) is a blast.
• Worker List added a new Workers right sidebar pane and populating the pane with debuggee workers. The next step is to add the about:debugging util for launching a new toolbox.
• Mapping minified variables started working on mapping minified variables, which will show the "original" variable name in the scopes pane, and enable preview, watch expressions and the console to work with original * expressions.
• Project Search continued to polish project search. This week we fixed keyboard navigation of streaming results, and made result orders deterministic.
• Syncing CSS removed the theme's CSS class namespace, which will make it easy to sync themes with m-c.
• Accidental Breakpoints fixed and uplifted a bug to 56, where the debugger created new breakpoints when the user changed original code and reloaded.
• File Search improved file search performance and fixed a bug where the debugger would crash on large files.
• Empty Lines landed disabled empty lines where the debugger disables lines that do not have any executable code.
• Photon started styling the debugger for the new photon design. It is looking great!
• Welcome Box styled the welcome box and added some additional shortcuts.
• Release released a new version of the debugger to nightly, which included the last month of work. We'll start getting feedback on it now that it's in nightly.

• Finished move to JSX for all of our components
• Improved testing of intermittents, we now have a script that finds them
• Progress on the AST breakpoints -- we have added a util and tests for finding ast locations. Next step, add to breakpoint syncing
• Improved breakpoints syncing -- we can now delete breakpoints that move outside of a source

• the search combination keys for text are now displayed and style
• Added copy functionality to the context menu of the editor

• new release this week will include project search and outline view
• empty line gutters are no longer going to be clickable: PR
• Async/await stepping is in progress. Jaideep did a lot of great work.
• Improved development experience for windows users
• Source tree now handles files and folders with the same name in a reasonable manner
• Source tree has also been generally cleaned up
• Debugger uses the Object Inspector from Core (same as the console)

• We're switching to JSX
• Project Search is getting close
• Lots of test and code quality fixes
• Lots of small paper cut fixes

• UI Polish
• Bug Fixes
• Project Search

• lots of polish as we prepare for releasing in 56
• breakpoints are more stable
• project text search is getting closer
• wasm support is coming to the debugger

lots happened since the last update:

• Edge Cases: pretty print, symmetric breakpoints, …
• Performance: stepping, preview
• UI: New symbol modal, full project text search
• Experiments: Call Site Breakpoints, Async stepping

• Flow Review
• Tests Review

It's been a quieter week than last week. This weeks highlights include:

• new UI improvements to search (thank you to @ruturajv!
• some new documentation
• WTR runner

We focused this week on getting lots of bugfixes and community prs in

• Nightly is up to date with the latest debugger updates
• new styling for the Outline View, big thanks to @amelzer
• searchbar had a lot of improvements
• lots of dependencies were updated, thanks to @zaggy
• further work on getting more frameworks included on our framework frames. Thanks to @andreicristianpetcu

This was a really great week for QA improvements as the debugger is getting more stable each week.

• We now disable out of scope lines when the debugger pauses.
• We have huge updates to preview - it's faster, more consistent, and works for HTML elements
• Breakpoints are kept in sync as code changes. Big thanks to codehag
• We're chipping away at two new features: Outline View and Project Search

We focused this week on UI polish, bug fixing, and performance as we focus on getting ready for the June 15th Firefox 55 release.

• Intelligently place preview popups and tooltips
• Add an option for disabling Framework Frames
• Polish the search bar
• Speed up stepping performance

Here are some highlights from the week:

• 💛 Function highlighting
• 🚓 License checking for our dependencies
• 💅 Lots of UI polish

One of the most interesting debugger questions is what happens when the debugger stops? This post is a quick run-through that will give you some context so that you can dig in and answer your own questions.

• Adam dramatically improved our startup performance. pr
• Ryan completed the heroic and insane project of getting babel working with HTML inline JS. pr
• Diéssica jumped in and polished our Tabs UI
• We started converting our Prop Types to Flow Props. Thanks Mateusz and others for the help kicking this off!
• We added several new Jest component tests. Big thanks to Andrei for tackling async component updates. It was not an easy task!
• We re-added storybook this week and wrote our first stories for Frames and Tabs! The stories are also being tested on CI with the great percy.io.

• 🚅 Column Breakpoints
• 🍝 Framework Frames
• 💬 Watch Expressions
• 🍝 Copy Call Stack

• 🌽 We started working on proper code folding
• 🔍 landed support for getter values

• 📙 Framework Frames
• 🔍 Previewing Windows
• 🐜 Component + Integration Tests

• 🐜 Bucket Window Properties
• 👀 Display popover intelligently
• 👶 Formatting Functions

• 💠 Highlighting libraries
• ✉️ Simplifying Function Names
• 🍝 Collapsing Library frames
• 👶 Naming Library frames
• ◾ Blackboxing libraries

• ◾ Blackboxing
• 😘 ES6
• 👀 Preview
• ☎️ client

• 🔍 Function Search
• 🚥 Code Coverage

• 💅 Prettier
• 🔴 Persisted Breakpoints

• 😈 Jest
• 🔍 File Search
• 👀 Preview

• 🔍 Function Search
• 🌖 Dark Theme Polish

• 🔴 Testing Improvements
• 🐜 Lots of bug squashing