feat(bind): extend key binding support

[reubeno]

Extends the bind builtin to support binding key sequences to readline functions (previously it only supported shell commands). Bindings to more complex macros remain unimplemented.

• Adds support for parsing and binding key sequences to readline functions (e.g., "\C-a":beginning-of-line)
• Implements translation of InputFunction variants to reedline events in the interactive layer
• Refactors the parser to distinguish between shell command bindings and readline target bindings

[Copilot]

Pull Request Overview

This PR extends the bind builtin to support binding key sequences to readline functions (not just shell commands). It introduces a distinction between shell command bindings and readline function/command bindings, adds parsing for both types, implements translations of readline functions to reedline events, and includes comprehensive test coverage.

• Adds support for parsing and binding key sequences to readline functions (e.g., "\C-a":beginning-of-line)
• Implements translation of InputFunction variants to reedline events in the interactive layer
• Refactors the parser to distinguish between shell command bindings and readline target bindings

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
brush-parser/src/readline_binding.rs	Splits binding types into KeySequenceShellCommandBinding (for shell commands) and KeySequenceReadlineBinding (for readline functions/commands); adds parsing functions for both
brush-interactive/src/reedline/edit_mode.rs	Implements translate_input_function_to_reedline_event() to map InputFunction variants to reedline events; adds support for Repaint event
brush-interactive/src/interactive_shell.rs	Updates buffer handling logic to support programmatically-generated edit buffers from executed commands
brush-core/src/sys/unix/input.rs	Renames get_key_from_key_code() to try_get_key_from_key_code() and changes return type from Result to Option
brush-core/src/error.rs	Adds new error variant UnknownKeyBindingFunction for invalid function names
brush-builtins/src/bind.rs	Refactors to use new parser functions, adds parse_key_sequence_and_readline_target(), implements bind_key_sequence_to_readline_target(), adds escape sequence handling, includes unit tests

[github-actions]

Public API changes for crate: brush-core

Removed items

-pub fn brush_core::sys::input::get_key_from_key_code(key_code: &[u8]) -> core::result::Result<brush_core::interfaces::Key, brush_core::error::Error>

Added items

+pub brush_core::error::ErrorKind::UnknownKeyBindingFunction(alloc::string::String)
+pub fn brush_core::sys::input::try_get_key_from_key_code(key_code: &[u8]) -> core::option::Option<brush_core::interfaces::Key>
+pub brush_core::ErrorKind::UnknownKeyBindingFunction(alloc::string::String)

Public API changes for crate: brush-parser

Removed items

-pub struct brush_parser::readline_binding::KeySequenceBinding
-pub brush_parser::readline_binding::KeySequenceBinding::command: alloc::string::String
-pub brush_parser::readline_binding::KeySequenceBinding::seq: brush_parser::readline_binding::KeySequence
-pub fn brush_parser::readline_binding::parse_key_sequence_binding(input: &str) -> core::result::Result<brush_parser::readline_binding::KeySequenceBinding, brush_parser::BindingParseError>

Added items

+pub enum brush_parser::readline_binding::ReadlineTarget
+pub brush_parser::readline_binding::ReadlineTarget::Command(alloc::string::String)
+pub brush_parser::readline_binding::ReadlineTarget::Function(alloc::string::String)
+pub struct brush_parser::readline_binding::KeySequenceReadlineBinding
+pub brush_parser::readline_binding::KeySequenceReadlineBinding::seq: brush_parser::readline_binding::KeySequence
+pub brush_parser::readline_binding::KeySequenceReadlineBinding::target: brush_parser::readline_binding::ReadlineTarget
+pub struct brush_parser::readline_binding::KeySequenceShellCommandBinding
+pub brush_parser::readline_binding::KeySequenceShellCommandBinding::seq: brush_parser::readline_binding::KeySequence
+pub brush_parser::readline_binding::KeySequenceShellCommandBinding::shell_cmd: alloc::string::String
+pub fn brush_parser::readline_binding::parse_key_sequence_readline_binding(input: &str) -> core::result::Result<brush_parser::readline_binding::KeySequenceReadlineBinding, brush_parser::BindingParseError>
+pub fn brush_parser::readline_binding::parse_key_sequence_shell_cmd_binding(input: &str) -> core::result::Result<brush_parser::readline_binding::KeySequenceShellCommandBinding, brush_parser::BindingParseError>

Performance Benchmark Report

Benchmark name	Baseline (μs)	Test/PR (μs)	Delta (μs)	Delta %
clone_shell_object	17.70 μs	17.23 μs	-0.47 μs	🟢 -2.65%
eval_arithmetic	0.15 μs	0.15 μs	-0.00 μs	⚪ Unchanged
expand_one_string	1.96 μs	1.98 μs	0.03 μs	⚪ Unchanged
for_loop	22.21 μs	22.60 μs	0.39 μs	🟠 +1.75%
function_call	2.57 μs	2.55 μs	-0.02 μs	⚪ Unchanged
instantiate_shell	58.16 μs	58.15 μs	-0.01 μs	⚪ Unchanged
instantiate_shell_with_init_scripts	24026.51 μs	24660.09 μs	633.58 μs	⚪ Unchanged
parse_bash_completion	2068.23 μs	2053.15 μs	-15.08 μs	⚪ Unchanged
parse_sample_script	2.02 μs	2.01 μs	-0.01 μs	⚪ Unchanged
run_echo_builtin_command	15.87 μs	16.54 μs	0.67 μs	⚪ Unchanged
run_one_external_command	2414.83 μs	2378.24 μs	-36.59 μs	🟢 -1.52%
tokenize_sample_script	3.55 μs	3.52 μs	-0.03 μs	⚪ Unchanged

Code Coverage Report: Only Changed Files listed

Package	Base Coverage	New Coverage	Difference
brush-builtins/src/bind.rs	🔴 0%	🔴 34.65%	🟢 34.65%
brush-core/src/options.rs	🟢 89%	🟢 88%	🔴 -1%
brush-core/src/shell.rs	🟠 73.69%	🟢 75.24%	🟢 1.55%
brush-core/src/sys/unix/input.rs	🔴 0%	🔴 24.49%	🟢 24.49%
brush-interactive/src/interactive_shell.rs	🟠 61.6%	🟠 63.49%	🟢 1.89%
brush-parser/src/readline_binding.rs	🔴 30%	🟠 74.12%	🟢 44.12%
Overall Coverage	🟢 71.52%	🟢 71.71%	🟢 0.19%

Minimum allowed coverage is 70%, this run produced 71.71%

Test Summary: bash-completion test suite

Outcome	Count	Percentage
✅ Pass	1345	63.77
❗️ Error	213	10.10
❌ Fail	182	8.63
⏩ Skip	354	16.79
❎ Expected Fail	14	0.66
✔️ Unexpected Pass	1	0.05
📊 Total	2109	100.00

[github-actions]

Test Results

    3 files     23 suites   7m 16s ⏱️
1 110 tests 1 110 ✅ 0 💤 0 ❌
3 310 runs  3 310 ✅ 0 💤 0 ❌

Results for commit 0c69c89.

[reubeno]

I've done some manual testing. This change makes things better for fzf shell integration. Sadly, atuin shell integration isn't looking as good as it did previously, but that seems more to be owing to upstream changes in that project's bash integration script.

Two steps forward, one step back.

With that said, this looks to be a general improvement so I'm going to move forward with merging it. There are still errors from readline "macros", though.