📝 Performant plain text editor for iOS with syntax highlighting, line numbers, invisible characters and much more.

Describe the bug Can't handle Korean input correctly

Screenshots

https://user-images.githubusercontent.com/7934444/166901295-93cb41aa-131d-4289-bab3-af121ad6d3c0.MOV

I came across another subtle difference in behaviour when switching to Runestone: When the TextView is not the first responder, programatically calling insertText with some text didn't do anything, while my previous implementation that used UITextView did append the text.

This PR changes the behaviour of TextView.insertText(_:) to also append the text at the end. I kept the behaviour of TextInputView.insertText(_:) the same (i.e., it will not insert the text if there's no marked or selected range) in case that this was on purpose.

Describe the bug Downloading the repo from GitHub and double clicking on Package.swift fails to build.

To Reproduce Download the repo from GitHub, double click Package.swift.

Expected behavior Builds.

Screenshots

I get a similar error when trying to open the Example project:

Additional context I checked Getting Started but I didn't see any additional steps spelled out. I'm not sure what I'm doing wrong

Is your feature request related to a problem? Please describe. The theme system allows specifying a single theme, which would be optimised for either light or dark mode. There doesn't yet seem a way to either set a single theme that supports both light and dark mode, or specify a theme per interface style.

Describe the solution you'd like This could be addressed by providing multiple themes, one per UIUserInterfaceStyle, or by providing support for themes that support multiple interface styles.

Describe alternatives you've considered

• I've tried adjusting the Color Set in my asset catalog to provide alternative colours for light and dark mode. This seems to work for a subset of colours, but notable not for the background colours. I'm also not sure if that's fully compatible with the internals of Runestone.
• Detect this on my view controllers, and then set the new theme.

Additional context I'm happy to provide a PR for this, but I'm not sure if this is desired and, if so, which approach would be the best fit for this framework.

Is your feature request related to a problem? Please describe. "The problem" is that Runestone uses font ligatures, so it joins characters like == != <= => <==> together.

Example: (with JetBrains Mono)

Describe the solution you'd like An option to disable font ligatures.

Describe alternatives you've considered /

Describe the bug Inserting characters to a TextView programmatically, for example from a keyboard input view with quick access special keys, seems to be done by calling insertText(_ text: String) method on TextView. This adds the characters and they appear, but the caret is not moved after the newly inserted characters but stays where it was, even though the implementation seems to attempt to move the caret.

Typing more characters using the native keyboard does move the caret after the new text. Also moving the caret using arrow keys does begin moving from the position where the caret was supposed to be. So it seems like the caret position (selectedRange?) has the correct value, but it is not reflected in the TextView after text insertion.

I also tried to move the caret programmatically, by adjusting selectedRange's location property, but it results in the caret being moved too many steps ahead.

To Reproduce

• Call textView.insertText("a") on an existing TextView instance.
• New characters appear but the caret stays in the same location before the inserted characters.

Expected behavior Caret should move to a position after the newly inserted characters.

Describe the bug Go to line doesn't scroll the line into safe area when virtual keyboard is visible

To Reproduce

• Open Example project
• In MainViewController, add a new action which always runs self?.contentView.textView.goToLine(50)
• Debug
• Open a document which contains more than 50 lines, scroll to the very top of the document
• Run the action
• Line 50 is revealed to the bottom of the viewport but it's covered by the visible virtual keyboard

Expected behavior Line 50 should be above the keyboard

Screenshots

Lastly thank you for the project, it reminds me of Codemirror and TextMate, both kind of become de factor standard on their own platform.

This is a great library and works really well, and I enjoyed the challenge of wrapping my head around Tree-sitter!

I'm using Runestone's TextView in a project that allows writing expressions including Xcode-like autocompletion that is anchored to the selected text. That requires the ability to subclass TextView (to intercept certain keystrokes for interacting with the autocompletion list) and to access the underlying UITextInput protocol (to get the rectangle of the selection, to put the autocompletion list next to it).

For consistency, I made the various methods that are overridden open or that provide UITextInput-like functionality.

Describe the bug When adding a TextView as a subview in a UIViewController in a Catalyst build there's an immediate crash when tapping into the TextView (and making first responder).

Error is: Runestone/TextInputView.swift:1287: Fatal error: Positions must be of type IndexedPosition looks like position is nil.

Screenshots

Closes #34

• When isEditable is true, text is still selectable and users are able to copy the text.
• When isSelectable is true then the user will not be able to do anything to the text.

Describe the bug Double digit line numbers truncate with a font size greater or equal to 20

To Reproduce

1. Open the Example project.
2. Navigate to OneDarkTheme.swift.
3. Set the font to a size of 20 or greater.
4. Run the project
5. Set theme to One Dark
6. Enter enough new lines to see 10 rows

Expected behavior

• Line numbers don't truncate.
• Line number gutter increases in width to accommodate the double digits at the larger font size.

Screenshots

Is your feature request related to a problem? Please describe. Folding code blocks would be a very nice addition 😋

Describe the solution you'd like Clicking an arrow or plus/minus sign would toggle expanding (unfold) and collapsing (fold) of an user selected code block. This allows the user to manage large amounts of text while viewing only those subsections that are currently of interest.

Reference https://en.wikipedia.org/wiki/Code_folding

Is your feature request related to a problem? Please describe. Swift Playgrounds (iPad in my case but should be applicable on Mac as well) cannot import packages that have C code included.

Describe the solution you'd like I haven’t looked deeply into the implementation but I’d hope for either of the following:

1. A separate package for the editor vs the language parsers
2. Perhaps the language/C code could be provided via a pre-compiled package instead?

Again, I may be over-simplifying the solution as I’m not familiar enough to understand the problem atm.

Describe alternatives you've considered Atm, I have to move the project to Xcode if I want to include this package (which I do), but I’m holding off on the editor bits for now because everything else can be built successfully on iPad.

Additional context Thank you for open sourcing such a high quality editor. I’ve worked on this kind of thing before and its an truly a huge undertaking, you’ve done an incredible job! I’ve bought your Runestone app as well and its become a huge part of my daily workflow 👌

It doesn’t have language support for some things (like XML) but I noticed I can still open it as plain text which is great 👍

Multicursor support is difficult if not impossible to implement in touch-based text editors, but since iPads support both keyboard and mouse/trackpad it would be a nice feature to have when, e.g., a Magic Keyboard is attached.

It'd be great to have an option on gutter layout to specify a minimum width. Specifically to solve the text view "jumping" when hitting double (or more) digits. This would be especially nice if code is less than 3 digits.

Describe the bug

I've integrated Runestone into one of my apps, where it gets displayed in a SwiftUI view using UIHostingView. I'm seeing some occasional crashes which seem to come from the OperationQueue in TreeSitterInternalLanguageMode.

I am not sure how to best address this. Any advice would be appreciated.

To Reproduce

No reliably steps to reproduce yet, as it's not deterministic.

Additional context

Sample stacktrace from an iPad Pro running iOS 15.5 (19F77), from the main thread:

Thread 0#0	(null) in objc_release ()
#1	(null) in -[NSOperationQueue dealloc] ()
#2	(null) in TreeSitterInternalLanguageMode.__deallocating_deinit ()
#3	(null) in _swift_release_dealloc ()
#4	(null) in bool swift::HeapObjectSideTableEntry::decrementStrong<(swift::PerformDeinit)1>(unsigned int) ()
#5	(null) in IndentController.__deallocating_deinit ()
#6	(null) in _swift_release_dealloc ()
#7	(null) in @objc TextInputView.__ivar_destroyer ()
#8	(null) in object_cxxDestructFromClass(objc_object*, objc_class*) ()
#9	(null) in objc_destructInstance ()
#10	(null) in _objc_rootDealloc ()
#11	(null) in -[UIResponder dealloc] ()
#12	(null) in -[UIView dealloc] ()
#13	(null) in @objc TextView.__ivar_destroyer ()
#14	(null) in object_cxxDestructFromClass(objc_object*, objc_class*) ()
#15	(null) in objc_destructInstance ()
#16	(null) in _objc_rootDealloc ()
#17	(null) in -[UIResponder dealloc] ()
#18	(null) in -[UIView dealloc] ()
#19	(null) in -[UIScrollView dealloc] ()
#20	(null) in @objc PlatformViewHost.__ivar_destroyer ()
#21	(null) in object_cxxDestructFromClass(objc_object*, objc_class*) ()
#22	(null) in objc_destructInstance ()
#23	(null) in _objc_rootDealloc ()
#24	(null) in -[UIResponder dealloc] ()
#25	(null) in -[UIView dealloc] ()
#26	(null) in (anonymous namespace)::destroyGenericBox(swift::HeapObject*) ()
#27	(null) in _swift_release_dealloc ()
#28	(null) in partial apply for thunk for @callee_guaranteed (@unowned UnsafePointer<A1>) -> (@unowned Attribute<A>, @error @owned Error) ()
#29	(null) in _swift_release_dealloc ()
#30	(null) in swift_arrayDestroy ()
#31	(null) in _ContiguousArrayStorage.__deallocating_deinit ()
#32	(null) in _swift_release_dealloc ()
#33	(null) in swift_arrayDestroy ()
#34	(null) in _ContiguousArrayStorage.__deallocating_deinit ()
#35	(null) in _swift_release_dealloc ()
#36	(null) in swift_arrayDestroy ()
#37	(null) in _ContiguousArrayStorage.__deallocating_deinit ()
#38	(null) in _swift_release_dealloc ()
#39	(null) in DisplayList.ViewUpdater.deinit ()
#40	(null) in DisplayList.ViewUpdater.__deallocating_deinit ()
#41	(null) in _swift_release_dealloc ()
#42	(null) in DisplayList.ViewRenderer.deinit ()
#43	(null) in DisplayList.ViewRenderer.__deallocating_deinit ()
#44	(null) in _swift_release_dealloc ()
#45	(null) in @objc _UIHostingView.__ivar_destroyer ()
#46	(null) in object_cxxDestructFromClass(objc_object*, objc_class*) ()
#47	(null) in objc_destructInstance ()
#48	(null) in _objc_rootDealloc ()
#49	(null) in -[UIResponder dealloc] ()
#50	(null) in -[UIView dealloc] ()
#51	(null) in _UIHostingView.__deallocating_deinit ()
#52	(null) in @objc _UIHostingView.__deallocating_deinit ()
#53	(null) in AutoreleasePoolPage::releaseUntil(objc_object**) ()
#54	(null) in objc_autoreleasePoolPop ()
#55	(null) in -[UIView dealloc] ()
#56	(null) in -[UITableViewCell .cxx_destruct] ()
#57	(null) in object_cxxDestructFromClass(objc_object*, objc_class*) ()
#58	(null) in objc_destructInstance ()
#59	(null) in _objc_rootDealloc ()
#60	(null) in -[UIResponder dealloc] ()
#61	(null) in -[UIView dealloc] ()
#62	(null) in -[UITableViewCell dealloc] ()
#63	(null) in __RELEASE_OBJECTS_IN_THE_ARRAY__ ()
#64	(null) in -[__NSArrayM dealloc] ()
#65	(null) in -[__NSOrderedSetM dealloc] ()
#66	(null) in cow_cleanup ()
#67	(null) in -[__NSDictionaryM dealloc] ()
#68	(null) in -[UITableView .cxx_destruct] ()
#69	(null) in object_cxxDestructFromClass(objc_object*, objc_class*) ()
#70	(null) in objc_destructInstance ()
#71	(null) in _objc_rootDealloc ()
#72	(null) in -[UIResponder dealloc] ()
#73	(null) in -[UIView dealloc] ()
#74	(null) in -[UIScrollView dealloc] ()
#75	(null) in -[UITableView dealloc] ()
#76	(null) in cow_cleanup ()
#77	(null) in -[__NSDictionaryM dealloc] ()
#78	(null) in -[UIViewController .cxx_destruct] ()
#79	(null) in object_cxxDestructFromClass(objc_object*, objc_class*) ()
#80	(null) in objc_destructInstance ()
#81	(null) in _objc_rootDealloc ()
#82	(null) in -[UIResponder dealloc] ()
#83	(null) in -[UIViewController dealloc] ()
#84	(null) in object_cxxDestructFromClass(objc_object*, objc_class*) ()
#85	(null) in objc_destructInstance ()
#86	(null) in _objc_rootDealloc ()
#87	(null) in cow_cleanup ()
#88	(null) in -[__NSDictionaryM dealloc] ()
#89	(null) in object_cxxDestructFromClass(objc_object*, objc_class*) ()
#90	(null) in objc_destructInstance ()
#91	(null) in _objc_rootDealloc ()
#92	(null) in object_cxxDestructFromClass(objc_object*, objc_class*) ()
#93	(null) in objc_destructInstance ()
#94	(null) in _objc_rootDealloc ()
#95	(null) in -[UIResponder dealloc] ()
#96	(null) in -[UIViewController dealloc] ()
#97	(null) in @objc PlatformViewHost.__ivar_destroyer ()
#98	(null) in object_cxxDestructFromClass(objc_object*, objc_class*) ()
#99	(null) in objc_destructInstance ()
#100	(null) in _objc_rootDealloc ()
#101	(null) in -[UIResponder dealloc] ()
#102	(null) in -[UIView dealloc] ()
#103	(null) in (anonymous namespace)::destroyGenericBox(swift::HeapObject*) ()
#104	(null) in _swift_release_dealloc ()
#105	(null) in partial apply for thunk for @callee_guaranteed (@unowned UnsafePointer<A1>) -> (@unowned Attribute<A>, @error @owned Error) ()
#106	(null) in _swift_release_dealloc ()
#107	(null) in swift_arrayDestroy ()
#108	(null) in _ContiguousArrayStorage.__deallocating_deinit ()
#109	(null) in _swift_release_dealloc ()
#110	(null) in DisplayList.ViewUpdater.deinit ()
#111	(null) in DisplayList.ViewUpdater.__deallocating_deinit ()
#112	(null) in _swift_release_dealloc ()
#113	(null) in DisplayList.ViewRenderer.deinit ()
#114	(null) in DisplayList.ViewRenderer.__deallocating_deinit ()
#115	(null) in _swift_release_dealloc ()
#116	(null) in @objc _UIHostingView.__ivar_destroyer ()
#117	(null) in object_cxxDestructFromClass(objc_object*, objc_class*) ()
#118	(null) in objc_destructInstance ()
#119	(null) in _objc_rootDealloc ()
#120	(null) in -[UIResponder dealloc] ()
#121	(null) in -[UIView dealloc] ()
#122	(null) in _UIHostingView.__deallocating_deinit ()
#123	(null) in @objc _UIHostingView.__deallocating_deinit ()
#124	(null) in AutoreleasePoolPage::releaseUntil(objc_object**) ()
#125	(null) in objc_autoreleasePoolPop ()
#126	(null) in _CFAutoreleasePoolPop ()
#127	(null) in __CFRunLoopPerCalloutARPEnd ()
#128	(null) in __CFRunLoopRun ()
#129	(null) in CFRunLoopRunSpecific ()
#130	(null) in GSEventRunModal ()
#131	(null) in -[UIApplication _run] ()
#132	(null) in UIApplicationMain ()
#133	0x00000001002271a8 in main at /Users/adrian/Development/maparoni/Maparoni/helpers/OSLog+Loggers.swift:18

Hello, I'm integrating the Runestone framework into my rule editor, and it's awesome, especially the highlight and line number stuffs!

And after integrating the syntax highlight, I try to do some analysis using the tree parsed by the tree-sitter, and I found the tree is stored in textView privately. So, is there any way to get that tree inside the textView?