Today we're releasing the first Sublime Merge build of the year - Build 2047! This build brings plenty of new features and enhancements.

Continue reading the full post for more details.

From the first release of Sublime Merge, we talked about the simple joy of software that ‘gets it really right’. For our team it means going beyond the minimum, making software as good as it can be, and paying attention to the details.

It’s been almost two years since Sublime Merge was launched, and our focus hasn’t changed. Our aim for the newest update was to ‘get it really right’ when it comes to flexibility and customization.

Our community uses Sublime Merge in many different ways; from reviewing commits on a tablet, to writing thousands of lines of code on a desktop computer.

The latest version of Sublime Merge is packed full of upgrades, but we want to highlight some of the ways we’re giving you flexibility in the way you work. We’ve included the full list of changes at the bottom of this post (spoiler: there’s a lot)

• Repository-Level Tabs - use tabs to quickly navigate between multiple repositories
• Upgraded Commit UI - focus on what’s important with an upgraded commit UI
• Flexible Layouts - adapt the layout to fit your context and workflow
• Hardware Acceleration - harness your device's power with OpenGL rendering

To get started straight away, visit the download page.

Tabs. Tabs. Tabs.

As developers, we know that windows can be cumbersome. We want to give you the tools you need to focus on your work, not on managing windows.

The new update provides the flexibility to view all your projects in one window.

Repository Level Tabs

Upgraded Commit UI

We’ve re-worked the commit UI to support different workflows. You can now configure the commit message position, and toggle between individual files using file tabs. You’ll also notice the new file stats.

Upgraded Commit UI

Your Git Client. Your Layout.

With the wide variety of displays available today, it’s important to have a flexible layout that works for you. Starting today, you can simply select the layout that fits your set up. Whether you’re on your 4K desktop screen, your work laptop, or even a tablet, we’ve got you covered.

Flexible Layouts

Even Faster 🚀

We're excited to announce support for hardware acceleration in Sublime Merge. Powered by OpenGL, this will deliver significant rendering performance improvements on all platforms. It is enabled by default on MacOS, and can be controlled via the advanced section of the preferences.

What’s Next

Review Workflow

Many of us use Sublime Merge to manage and share our work, but some of us also use it to review work. File tabs have improved this process significantly, but there’s more work to do. Keep your eyes out for multiple improvements focused on improving your ability to review.

Image Diffs

If you’re using Git, chances are you’re working with images too. Just like code, it’s important to see what’s changed when modifying image files. We want to make reviewing image changes as seamless as reviewing code changes.

Plugin Support

It’s incredible to see what the community has built using the plugin system for Sublime Text. The plugin system offers the power and flexibility needed to truly personalize your experience. We know this is an important part of software that gets it really right, so we’ll be bringing it to Sublime Merge.

The Team Behind Sublime Merge

We’ve got big plans for the Sublime Merge team, and we’re full steam ahead! Our team is growing, and we’d like to welcome our new developer, David! You can thank him for features such as commit stats, the new console, and some great performance improvements in Sublime Merge.

Hello hello, I’m David, one of the software engineers at Sublime HQ. I’m usually the quiet guy that enjoys making silly jokes whenever I’m given the chance. As a programmer, I enjoy learning how to make traditional software, and writing clean compact code. In my own time I’ve been learning how to draw digitally.

Feedback

As always, we’re excited to hear your thoughts. We’ll be on the forum listening to any feedback. We also have an official bug tracker, where you can share your ideas for features.

Thank You

We know times are tough on a global scale at the moment, and our thoughts are with all of you. We’d like to take this time to thank you for your feedback and participation, whether it be on the forums or the Discord server. Through this, you have guided Sublime Merge to where it is today. We’re excited to continue delivering the best Git experience to you.

Sublime Merge 2 Changelog

General

• New UI, including repository tabs
• GPU Rendering
• UI: Reworked Commit Dialog
• UI: Added repository tabs, to have multiple repositories open in a single window
• UI: Added file tabs when viewing the contents of a commit
• Implement commit signature creation and validation
• Added a lines changed indicator to commits
• Added command history, available from the Show Git Output icon in the tool bar
• Added commit message history, available from the dropdown arrow in the commit message box
• Added support for non-overlay scrollbars in diffs
• Added Resolve Ours / Resolve Theirs dropdown to unmerged files
• URLs in commit messages and git output can be opened via the context menu
• Left and Right keys can be used to expand/collapse merge commits
• Added Navigate/Go to Child
• Stash commands no longer supply -q by default, to work around a bug in Git 2.24
• Checking out a hidden ref will make the ref visible
• Add Recent Repositories to Welcome Page
• Search: Added before and after operators
• Added set_preference and toggle_preference commands
• Added gitflow publish support
• Preferences: Updating settings via the preferences dialog no longer clears comments in the settings file
• Preferences: Added Preferences entry for Ignore Whitespace in diffs
• Added checks for pushDefault and pushRemote when pushing
• Added Tools/Show Console
• Improved selection behavior while loading large repositories
• Improved menu auto hide behavior on Linux and Windows
• Improved performance with a very large number of untracked or modified files
• Improved performance in repositories with a large number of authors
• Running smerge without any arguments will focus the current window, if any
• Fixed not being able to commit when email is set to empty string
• Fixed a bug in destination path calculation in the clone dialog
• Fixed Create Tag with an empty message creating the tag incorrectly
• Fixed hunk staging using the wrong encoding in some scenarios
• Fixed shift+enter staging a file even when focus is in commit message box

Merge Tool

• Indentation settings are now automatically detected from the contents of the file
• Saving a file with unresolved conflicts will warn before saving
• Added a preference to trim trailing whitespace on save

GPU Rendering

• New hardware_acceleration setting will composite the UI on the GPU
• By default, GPU rendering is enabled on Mac, and disabled on Windows and Linux. This can be changed via the Preferences dialog.
• Details about the active GPU will be displayed in the Console

Git

• Git: Added support for smudge and clean filters, enabling Git LFS support
• Git: Improved handling of the working-tree-encoding attribute
• Git: Improved parsing of .gitattributes files
• Git: Added support for GUI encoding config
• Windows and Mac: Updated bundled Git to 2.26.2
• Windows: Fixed core.worktree support
• Submodules: Added Initialize All Submodules context menu
• Submodules: The location bar now indicates the value of HEAD for each submodule

Editor Control

• Expanded draw_white_space setting, supporting leading and trailing white space
• Unicode white space characters, such as the zero width no-break space, are now drawn as hex values. Controlled via draw_unicode_white_space setting.
• Spell Checking: Added support for languages with upper case characters after start of word
• Spell Checking: Updated dictionaries
• Spell Checking: Added support for non-utf8 dictionaries
• Spell Checking: System dictionaries are now available on Linux
• Spell Checking: Dictionaries in ~/Library/Spelling are now available on Mac
• Linux: Text drag and drop is now supported
• Linux: Added support for alternate font weight names
• Linux: Selection is no longer cleared when another application makes a selection

Text Commands

• Improved behavior of Wrap Paragraph
• Improved behavior of Swap Lines
• Added Selection/Expand Selection as a general mechanism to expand the selection
• Selection/Split into Lines will now split a selection into words if the selection doesn't contain any newlines
• Fixed swap_line_down not being able to swap an empty line onto the last line of a file

Input Handling

• Modifier key taps can now be used as part of a key binding. For example, ["ctrl", "ctrl"] will trigger when Ctrl is pressed twice without pressing any other keys in between.
• Linux: AltGr can now be used in key bindings via altgr
• Linux: Added a workaround for a touchscreen driver bug, which would cause right click and mouse scrolling to stop working
• Linux: When the menu is hidden, pressing alt will show it
• Linux: Improved compatibility with some keyboard layouts
• Mac: Fix Pinyin input
• Mac: Keypad keys can now be bound to as expected
• Mac: Improved compatibility with some keyboard layouts
• Windows, Linux: Hide mouse cursor when typing. Controlled via hide_pointer_while_typing setting.
• Windows, Linux: Fixed being unable to bind Ctrl+Break
• Windows: Improved IME support
• Windows, Linux: Added Shift+F10 key binding to open the context menu

UI

• Added highlight_gutter and highlight_line_number settings
• Themes now have a style property for title_bar element, for better integration with OS "dark modes"
• Color Schemes: Added glow font option to color schemes
• Color Schemes: Added support for the underline font style
• Linux: Show sequential key bindings in the menu
• Linux: Fixed context menu position being slightly offset

Rendering

• Windows, Linux: Added support for per-display subpixel ordering
• Mac: Improved window resize performance
• Windows: Fixed rendering bug where other applications could cause persistent artifacts via window animations

Application Behavior

• Added Safe Mode, to simulate a clean install. Enabled by passing --safe-mode on the command line.
• Holding down Shift on Windows, or Option on macOS, will start Sublime Merge in Safe Mode
• Settings containing a UTF-8 BOM will no longer fail to load

Syntax Definitions

• Added ability to "branch" within syntax definitions, for non-deterministic or multi-line constructs
• Many syntax highlighting improvements, including significant improvements to:
  • Erlang, with thanks to deathaxe
• Improved syntax definition load time
• Fixed a performance issue with bounded repeats in regular expressions

When we implemented the git portion of Sublime Merge, we chose to use mmap for reading git object files. This turned out to be considerably more difficult than we had first thought. Using mmap in desktop applications has some serious caveats, and here's why:

You can follow along with the example project here.

Say you were reading some binary format, data you need throughout some application. You take the easiest approach and use a simple read to get the full contents of the file. You release your software and someone comes along and says: "I need to parse this 3GB file, but I only have 2GB of memory. Could you make it so that you're not using so much memory?". Of course you want to help them, so you do some searching and come to the conclusion that memory mapping is the perfect solution to this problem.

Memory mapped files work by mapping the full file into a virtual address space and then using page faults to determine which chunks to load into physical memory. In essence it allows you to access the file as if you had read the whole thing into memory, without actually doing so. Crucially it requires only a small change to the codebase:

And with that, you've fixed the memory usage issue. You've fixed the bug, people are happy and all is well until you get another support ticket. Your program is crashing with a SIGBUS.

Caveat 1: SIGBUS

SIGBUS (bus error) is a signal that happens when you try to access memory that has not been physically mapped. This is different to a SIGSEGV (segmentation fault) in that a segfault happens when an address is invalid, while a bus error means the address is valid but we failed to read/write.

As it turns out, the ticket comes from someone using a networked drive. Their network happened to disconnect while your memory mapped file was open, and since the file no longer existed the OS couldn't load it into ram for you and gave you a SIGBUS instead.

Because the OS is loading the file on demand, you now have this wonderful issue where any arbitrary read from an address into the memory mapped file can and will fail at some point.

Luckily on POSIX systems we have signal handlers, and SIGBUS is a signal we can handle. All you need to do is register a signal handler for SIGBUS when the program starts and jump back to our code to handle failures there.

Sadly our code actually has some edge cases we should consider:

Signal handlers are global, but signals themselves are per-thread. So you need to make sure you're not messing with any other threads by making all our data thread local. Let's also add some robustness by making sure we've called setjmp before longjmp.

Using setjmp and longjmping from a signal handler is actually unsafe. It seems to cause undefined behaviour, especially on MacOS. Instead we must use sigsetjmp and siglongjmp. Since we're jumping out of a signal handler, we need that signal handler to not block any future signals, so we must also pass SA_NODEFER to sigaction.

This is starting to get quite complicated, especially if you were to have multiple places where a SIGBUS could happen. Let's factor things out into functions to make the logic a little cleaner.

There, now you just need to remember to always call install_signal_handlers for every application, and wrap all file accesses with safe_mmap_try. Annoying, but manageable. So now you've covered POSIX systems, but what about Windows?

Caveat 2: Windows

Windows doesn't have mmap, but it does have MapViewOfFile. Both of these implement memory mapped files, but there's one important difference: Windows keeps a lock on the file, not allowing it to be deleted. Even with the Windows flag FILE_SHARE_DELETE deletion does not work. This is an issue when we expect another application to delete files from under us, such as git garbage collection.

One way around this with the windows API is to essentially disable the system file cache entirely, which just makes everything absurdly slow. The way Sublime Merge handles this is by releasing the memory mapped file on idle. Its not a pretty solution, but it works.

Windows also does not have a SIGBUS signal, but you can trivially use structured exception handling in safe_mmap_try instead:

Now all is well, your application functions on Windows. But then you decide that you would like some crash reporting, to make it easier to identify issues in the future. So you add Google Breakpad, but unbeknownst to you you've just broken Linux and MacOS again…

Caveat 3: 3rd Parties

The problem with using signal handlers is that they're global, across threads and libraries. If you have or have added a library like Breakpad that uses signals internally you're going to break your previously safe memory mapping.

Breakpad registers signal handlers at initialization time on Linux, including one for SIGBUS. These signal handlers override each other, so installation order is important. There is not a nice solution to these types of situations: You can't simply set and reset the signal handler in safe_mmap_try as that would break multithreaded applications. At Sublime HQ our solution was to turn an unhandled SIGBUS in our signal handler into a SIGSEGV. Not particularly elegant but it's a reasonable compromise.

On MacOS things get a little more complicated. XNU, the MacOS kernel, is based on Mach, one of the earliest microkernels. Instead of signals, Mach has an asynchronous, message based exception handling mechanism. For compatibility reasons signals are also supported, with Mach exceptions taking priority. If a library such as Breakpad registers for Mach exception messages, and handles those, it will prevent signals from being fired. This is of course at odds with our signal handling. The only workaround we've found so far involves patching Breakpad to not handle SIGBUS.

3rd party libraries are a problem because signals are global state accessible from everywhere. The only available solutions to this are unsatisfying workarounds.

Caveat 4: 32bit Support

Memory mapping may not use physical memory, but it does require virtual address space. On 32bit platforms your address space is ~4GB. So while your application may not use 4GB of memory, it will run out of address space if you try to memory map a too large file. This has the same result as being out of memory.

Sadly this doesn't have a workaround like the other issues, it is a hard limitation of how memory mapping works. You can now either rewrite the codebase to not memory map the whole file, live with crashes on 32bit systems or not support 32bit.

With Sublime Merge and Sublime Text 3.2 we took the "no 32bit support" route. Sublime Merge does not have a 32bit build available and Sublime Text disables git integration on 32bit versions.

An Alternative

I mentioned before that you can rewrite your code to not use memory mapping. Instead of passing around a long lived pointer into a memory mapped file all around the codebase, you can use functions such as pread to copy only the portions of the file that you require into memory. This is less elegant initially than using mmap, but it avoids all the problems you're otherwise going to have.

Through some quick benchmarks for the way Sublime Merge reads git object files, pread was around ⅔ as fast as mmap on linux. In hindsight it's difficult to justify using mmap over pread, but now the beast has been tamed and there's little reason to change any more.

If you think we've missed something or made a mistake, please leave us a message on the forums. We hope this helps some of you in your future endeavours. If you haven't already, check out our git client Sublime Merge.

The past year has been busy here at Sublime HQ. We've grown our engineering team, shipped Sublime Text 3.1 and released our second product, Sublime Merge. If you use Git and like the ethos of Sublime Text, we think you'll love it.

Today we're pushing out Sublime Text 3.2, which builds off of a bunch of work we've done in Sublime Merge. This includes: first-class Git integration, incremental diffing, new theme functionality and block caret support. Beyond that is a slew of other enhancements, stability improvements and performance gains. See the full changelog below for details.

Sublime Text 3.2 is available from the Download page.

Git status badges in the side bar and incremental diff markers in the gutter

Changelog

Git Integration New!

• Files and folders in the sidebar will now display badges to indicate Git status
• Ignored files and folders are visually de-emphasized
• The current Git branch and number of modifications is displayed in the status bar
• Commands have been added to open a repository, see file or folder history, or blame a file in Sublime Merge
• Themes may customize the display of sidebar badges and status bar information
• The setting show_git_status allows disabling Git integration
• All file reads are done through a custom, high-performance Git library written for Sublime Merge
• Read the documentation

Incremental Diff New!

• All changes to a document are now represented by dedicated markers in the gutter
• Diff markers show added, modified and deleted lines
• The setting mini_diff controls incremental diff behavior
• In coordination with the new Git functionality, diffs can be calculated against HEAD or the index
• The git_diff_target setting controls base document source
• API methods View.set_reference_document() and View.reset_reference_document() allow controlling the diff
• The following diff-related commands were added:
  • Next Modification
  • Previous Modification
  • Revert Modification
• Full inline diffs of each change can be displayed via the right-click context menu, or keyboard shortcuts
• Inline diff presentation can be changed by customizing a color scheme
• Read the documentation

Editor Control

• Added block_caret setting
• Improve positioning and sizing of gutter icons in some situations
• Fixed draw_minimap_border setting not working
• Linux: Improved input method (IM) support - fcitx, ibus, etc
• Linux: Fixed a crash when using GTK_IM_MODULE=xim
• Linux: Tweaked behavior of up/down when on the first and last lines of a file to better match platform conventions
• Windows: Improved IME support

Themes/UI

• Enhanced the .sublime-theme format:
  • Added variables support and associated revised JSON format with variables key
  • Added extends keyword to have one theme derive from another
  • Colors may be specified via CSS syntax
• Improved performance with large numbers of rules in a .sublime-theme
• Linux: Moved to GTK3
• Linux: Various high DPI fixes
• Mac: Added Mojave support
• Mac: Add full support for macOS native tabs
• Mac: Ensure context menus are shown without scrolling
• Mac: Error message dialogs can now be closed with the escape key
• Mac: Improved window placement
• Mac: Improved resize performance
• Windows: Fixed minimized and maximized state not restoring
• Windows: Fixed a bug where auto complete entries would contain an ellipsis when not required

Text Rendering

• Support for Unicode 11.0
• Improved rendering of combining characters
• Fixed a caret positioning bug when non-trivial graphemes are present
• Fixed some cases of incorrect glyph positions on Windows and Mac
• Linux: Color glyphs are now drawn properly on light backgrounds
• Windows: Fixed a rendering issue with certain combining characters
• Windows: Fixed some fonts having an incorrect baseline

Color Schemes

• Added block_caret key to use in conjunction with block carets
• caret values now respect alpha as expected, rather than pre-blending against the background color
• Added the foreground_adjust property to rules with a background. Accepts CSS color mod adjusters to manipulate the saturation, lightness or opacity of the foreground color.

Syntax Highlighting

• Many syntax highlighting improvements, including significant improvements to:
  • Clojure, with thanks to Nelo Mitranim
  • D
  • Go, with thanks to Nelo Mitranim
  • Lua, with thanks to Thomas Smith
• Fixed a crash that could occur when nesting embed patterns in .sublime-syntax files
• Syntax Tests: Allow syntax test files to have a UTF-8 BOM

Files and Folders

• Improve performance of file watching for ignored paths on Windows and Mac
• Windows: Fixed Open File treating paths as case-sensitive
• Windows: Properly unlock directories after contained files are closed

API

• Added View.set_reference_document() and View.reset_reference_document() to control diff generation
• Phantoms are now drawn correctly in conjunction with draw_centered
• Various minor improvements related to plugin module loading and unloading
• Added support for hwb() colors to minihtml
• Added a custom min-contrast() adjuster for the CSS color mod function in minihtml
• Mac: Fixed a plugin_host crash when running a process that itself crashes

Miscellaneous

• Fixed a Goto Symbol in Project performance regression
• F21..F24 keys can now be bound
• Assorted minor fixes and stability improvements
• Linux: Improved behavior of --wait command line argument when Sublime Text isn't currently running

Sublime Merge, our Git Client and Merge Tool, is out now with improvements to the Merge Tool, Tree viewing, and Clone dialog. See the full post for more details.

Sublime Text 3.2 will be coming very soon now, featuring Git integration and more.

Sublime HQ's Git Client, Sublime Merge, is out now with Interactive Rebase, a new Contents View, and Word Wrap - see the full post for more details.

While we continue to add more features and polish to the default Sublime Merge experience, we know that developers love the ability to tweak their tools. Sublime Merge is built on the same foundation as Sublime Text, so you can tweak key bindings, menus, command palette entries, and even the look and feel of the UI.

To assist, we’ve just rolled out a number of pages of documentation for users who wish to customize Sublime Merge to look and function a little differently. In addition, we’ve added a new documentation section for the dev builds of Sublime Text. It covers all of the features we added during the development of Sublime Merge.

Sublime Merge Build 1070 is out now with Commit Folding - see the full post for more details.

Just a quick post about what we're going to be adding to Sublime Merge. This isn't a comprehensive list, but it should give an indication of what we're focusing on right now.

• Branch Visualization. Sublime Merge itself handles large repositories well, but there's more the UI could do to help users with a lot of branches on the go. We've got some nice things cooking for this that will be coming in the near future. Stay tuned!
• Submodule Management. Sublime Merge understands submodules, but doesn't provide any UI for managing them. We'll be changing that soon.
• Tabs. Tabs have been frequently requested by users working on several repositories at once. The Switch Repository functionality (under the File menu) helps with this, but tabs have their own benefits, so they're on their way.
• Git Flow Integration. Git Flow is a branching strategy with an accompanying set of command line tools. We've had a lot of requests for UI support here, so it'll be making it in too.
• Interactive Rebase. Sublime Merge currently supports editing commit messages and squashing commits (available from the commit context menu). We'll be adding extra commit wrangling functionality, including reordering commits, moving commits between branches, and amending arbitrary commits.
• Plugins. Sublime Text style plugins are on our radar. This isn't at the top of the list, but they're coming.

We'll also be getting a new Sublime Text Dev Build out this week, rolling in all the updates from Sublime Merge, including the updated theming system and Mojave support.

(You can download Sublime Merge from https://www.sublimemerge.com/download)

There's a company that makes photography accessories, called Really Right Stuff. They make lovely equipment, but what I really like is the name. It embodies the idea of building something that goes beyond the minimum: making it as good as it can be, paying attention to the details, and getting it really right.

When it comes to software, getting it really right goes beyond functionality. The feel, aesthetics, and performance all have to be there.

There's a real pleasure using software that gets it really right, as a lot of the time, it doesn't. We're all too familiar with clunky layouts, unresponsive buttons, choppy scrolling, tedious splash screens, and flickering on every interaction.

After typing git add -p in the terminal one too many times, I thought to myself: we've got some pretty great tech in Sublime Text. What if we used it to build a Git client? Could we make it fast? Could we make it buttery smooth, without flickering or blocking? Could we make something that's really, really right?

Today, I'd like to introduce Sublime Merge. It combines the UI engine of Sublime Text, with a from-scratch implementation of Git*. The result is, to us at least, something pretty special.

Sublime Merge - Commit Dialog

You can download Sublime Merge, and try it for yourself - there's no time limit, no accounts, no metrics, and no tracking. The evaluation version is fully functional, but is restricted to the light theme only. Individual purchases are buy once, use forever, with 3 years of updates included in the purchase. Business licenses are available on a subscription basis. Sublime Merge runs on Windows, Mac and Linux.

It's still early days for Sublime Merge - it has only been used by us and our small team of beta testers so far. We'd love to hear what you think. We'll be on the Forums listening to any feedback - let us know how you get on with it!

* We have a custom implementation of Git for reading repositories, which drives a lot of our high performance functionality. However we defer to Git itself for operations that mutate the repository (Staging, Committing, Checking out branches, etc).