neovimcraft

plugins about

pluginmotion

2,789

CREATED

2022-03-13

UPDATED

16 days ago

leap.nvim

Leap is a general-purpose motion plugin for Neovim, with the ultimate goal of establishing a new standard interface for moving around in the visible area in Vim-like modal editors.

showcase

How to use it (TL;DR)

Leap allows you to jump to any positions in the visible editor area by entering a 2-character search pattern, and then potentially a label character to pick your target from multiple matches, similar to Sneak. The novel idea in Leap is its "clairvoyant" ability: you get a live preview of the target labels - by mapping possible futures, Leap can show you which key(s) you will need to press before you actually need to do that.

Initiate the search in the forward (s) or backward (S) direction, or in the other windows (gs).
Start typing a 2-character pattern ({c1}{c2}).
After typing the first character, you see "labels" appearing next to some of the {c1}{?} pairs. You cannot use the labels yet.
Enter {c2}. If the pair was not labeled, then voilà, you're already there. No need to be bothered by remaining labels, just continue editing.
Else: select a label. In case of multiple groups, first switch to the desired one, using <space> (step back with <tab>, if needed).

Why is this method cool?

It is ridiculously fast: not counting the trigger key, leaping to literally anywhere on the screen rarely takes more than 3 keystrokes in total, that can be typed in one go. Often 2 is enough.

At the same time, it reduces mental effort to almost zero:

You don't have to weigh alternatives: a single universal motion type can be used in all non-trivial situations.
You don't have to compose in your head: one command achieves one logical movement.
You don't have to be aware of the context: the eyes can keep focusing on the target the whole time.
You don't have to make decisions on the fly: the sequence you should enter is determined from the very beginning.
You don't have to pause in the middle: if typing at a moderate speed, at each step you already know what the immediate next keypress should be, and your mind can process the rest in the background.

Down the kangaroo hole

This was just a teaser - mind that Leap is extremely flexible, and offers much more beyond the defaults: you can configure it to resemble other similar plugins, extend it with custom targeting methods, and even do arbitrary actions with the selected target(s) - read on to dig deeper.

Design considerations in detail
Background
Status
FAQ
Getting started
Usage
Configuration
Extending Leap
Plugins using Leap

Design considerations in detail

The ideal

Premise: jumping from point A to B on the screen should not be some exciting puzzle, for which you should train yourself; it should be a non-issue. An ideal keyboard-driven interface would impose almost no more cognitive burden than using a mouse, without the constant context-switching required by the latter.

That is, you do not want to think about

the context: it should be enough to look at the target, and nothing else (↔ vanilla Vim motion combinations using relative line numbers and/or repeats)
the command: we need one fundamental targeting method that can bring you anywhere: a "jetpack" instead of a "railway network" (↔ EasyMotion and its derivatives)
the steps: the motion should be atomic (↔ Vim motion combos), and you should be able to type the sequence in one go, without having to make semi-conscious decisions on the fly (the ever-present dilemma when using //?: "Shall I try one more input character, or start a <C-g> streak?"), or having to react to events (labels appearing on the screen).

All the while using as few keystrokes as possible, and getting distracted by as little incidental visual noise as possible.

How do we measure up?

It is obviously impossible to achieve all of the above at the same time, without some trade-offs at least; but Leap comes pretty close, occupying a sweet spot in the design space.

The one-step shift between perception and action cuts the Gordian knot: while the input sequence can be scaled to any number of targets (by adding new groups you can switch to), ahead-of-time labeling eliminates the surprise factor: leaping is like doing incremental search with knowing in advance when to finish.

Fortunately, a 2-character search pattern - the shortest one with which we can play this trick - is also long enough to sufficiently narrow down the matches in the vast majority of cases. It is very rare that you should type more than 3 characters altogether to reach a given target.

Auxiliary principles

Optimize for the common case, not the pathological: a good example of this is the Sneak-like "one-character labels in multiple groups"-approach, which can become awkward for, say, 200 targets, but is usually more comfortable, eliminates all kinds of edge cases and implementation problems, and allows for features like multiselect.
Sharpen the saw: build on Vim's native interface, and aim for synergy as much as possible. The plugin supports macros, operators, dot-repeat (.), inclusive/exclusive toggle (v), multibyte text and keymaps (language mappings), autocommands via User events, among others, and intends to continuously improve in this respect.
Mechanisms instead of policies: Complement the small and opinionated core by extension points, keeping the plugin flexible and future-proof.

Background

Leap is a reboot of Lightspeed; a streamlined but in many respects enhanced version of its ancestor. Compared to Lightspeed, Leap:

gets rid of some gimmicks with a low benefit/cost ratio (like Lightspeed's "shortcut" labels), but works the same way in the common case; all the really important features are there
has a smaller and simpler visual footprint; it feels like using Sneak
is more flexible and extensible; it can be used as an engine for selecting arbitrary targets, and performing arbitrary actions on them

Status

The plugin is not fully stable yet, but don't let that stop you - the usage basics are extremely unlikely to change. To follow breaking changes, subscribe to the corresponding issue.

FAQ

-- Beware that the trade-off in this mode is that you always have to
-- select a label, as there is no automatic jump to the first target (it
-- would be very confusing if the cursor would suddenly jump in the
-- opposite direction than your goal). Former vim-sneak users will know
-- how awesome a feature that is. I really suggest trying out the plugin
-- with the defaults for a while first.

-- An additional disadvantage is that operations cannot be dot-repeated
-- if the search is non-directional.

-- Now that you have carefully considered my wise advice above, I'll
-- tell you the simple trick: just initiate multi-window mode with the
-- current window as the only target.

vim.keymap.set(<modes>, <your-preferred-key>, function ()
  local current_window = vim.fn.win_getid()
  require('leap').leap { target_windows = { current_window } }
end)

-- The same caveats as above about bidirectional search apply here.

vim.keymap.set('n', <your-preferred-key>, function ()
  local focusable_windows_on_tabpage = vim.tbl_filter(
    function (win) return vim.api.nvim_win_get_config(win).focusable end,
    vim.api.nvim_tabpage_list_wins(0)
  )
  require('leap').leap { target_windows = focusable_windows_on_tabpage }
end)

Check flit.nvim, an extension plugin for Leap.

See Extending Leap for an example snippet (30-40 lines).

Getting started

Requirements

Neovim >= 0.7.0

Dependencies

repeat.vim, for dot-repeats (.) to work as intended

Installation

Use your preferred method or plugin manager. No extra steps needed besides defining keybindings - to use the default ones, put the following into your config:

require('leap').add_default_mappings() (init.lua)

lua require('leap').add_default_mappings() (init.vim)

Note that the above function will check for conflicts with any custom mappings created by you or other plugins, and will not overwrite them, unless explicitly told so (called with a true argument).

Usage

Permalink to the example file, if you want to follow along.

The search is invoked with s in the forward direction, and S in the backward direction. Let's target some word containing ol. After entering the letter o, the plugin processes all character pairs starting with it, and from here on, you have all the visual information you need to reach your specific target.

quick example 1

To reach an unlabeled match, just finish the pattern, i.e., type the second character. For the rest, you also need to type the label character that is displayed right next to the match. (Note: the highlighting of unlabeled matches - green underlined on the screenshots - is opt-in, turned on for clarity here.)

To continue with the example, type l.

If you aimed for the first match (in oldwin->w_frame), you are good to go, just continue your work! The labels for the subsequent matches of ol remain visible until the next keypress, but they are carefully chosen "safe" letters, guaranteed to not interfere with your following editing command.

quick example 2

If you aimed for some other match, then type the label, for example u, and move on to that.

To show the last important feature, let's go back to the start position, and target the struct member on the line available = oldwin->w_frame->fr_height; near the bottom, using the pattern fr, by first pressing s, and then f:

quick example 3

The blue labels indicate the "secondary" group of matches, where we start to reuse the available labels for a given pair (s, f, n... again). You can reach those by prefixing the label with <space>, that switches to the subsequent match group. For example, to jump to the "blue" j target, you should now press r<space>j.

In very rare cases, if the large number of matches cannot be covered even by two label groups, you might need to press <space> multiple times, until you see the target labeled, first with blue, and then, after one more <space>, green. (Substitute "green" and "blue" with the actual colors in the current theme.)

Special cases and additional features

Resolving highlighting conflicts in phase one

If a directly reachable match covers a label, the match will get highlighted (telling the user, "Label underneath!"), and the label will only be displayed after the second input, that resolves the ambiguity.
If a label gets positioned over another label (this might occur before EOL or the window edge, when the labels need to be shifted left), an "empty" label will be displayed until entering the second input.

Cross-window motions

In this case, the matches are sorted by their screen distance from the cursor, advancing in concentric circles. The one default motion that works this way is gs (<Plug>(leap-from-window)), searching in all other windows on the tab page. To create custom motions like this, e.g. bidirectional search in the current window, see Extending Leap.

Visual and Operator-pending mode

Visual/Operator-pending s/S are like their Normal-mode counterparts, except that s includes the whole match in the selection/operation (which might be considered the more intuitive behaviour for these modes).

In these modes, there is also an additional pair of directional motions available, to provide more comfort and precision. x/X are to s/S as t/T are to f/F - they exclude the matched pair:

abcd|                    |bcde
████e  ←  Sab    sde  →  █████
ab██e  ←  Xab    xde  →  ███de

Note that each of the forward motions are inclusive (:h inclusive), and the v modifier (:h o_v) works as expected on them.

Jumping to the end of the line and to empty lines

A character at the end of a line can be targeted by pressing <space> after it. There is no special mechanism behind this: you can set aliases for the newline character simply by defining a set in opts.equivalence_classes that contains it.

Empty lines can also be targeted, by pressing the newline alias twice (<space><space> by default). This latter is a slightly more magical feature, but fulfills the principle that any visible position you can move to with the cursor should be reachable by Leap too.

Repeat and traversal

Pressing <enter> after invoking any of Leap's motions sets the search pattern to the previous one (special_keys.repeat_search).

After entering at least one input character, <enter> initiates "traversal" mode, moving on to the next match on each keypress (special_keys.next_phase_one_target or special_keys.next_target). In case you accidentally overshoot your target, <tab> can revert the previous jump(s) (special_keys.prev_target). Note that if the safe label set is in use, the labels will remain available the whole time!

Tips

When repeating the previous search, you can immediately move on: s<enter><enter>...
Accepting the first match after one input character is a useful shortcut in operator-pending mode (e.g. ds{char}<enter>).
Traversal mode can be used as a substitute for normal-mode f/t motions. s{char}<enter><enter> is the same as f{char};, but works over multiple lines.
For cross-window search, traversal mode is not supported (since there's no direction to follow), but you can still accept the first (presumably only) match with <enter>, even after one input.

Smart autojump

Leap automatically jumps to the first match if the remaining matches can be covered by a limited set of "safe" target labels (keys you would not use right after a jump), but stays in place, and switches to an extended, more comfortable label set otherwise (the trade-off becomes more and more acceptable as the number of targets increases, since the probability of aiming for the very first target becomes less and less). For fine-tuning, see :h leap-config (labels and safe_labels).

Configuration

Below is a list of all configurable values in the opts table, with their defaults. Set them like: require('leap').opts.<key> = <value>. For details on the particular fields, see :h leap-config.

max_phase_one_targets = nil
highlight_unlabeled_phase_one_targets = false
max_highlighted_traversal_targets = 10
case_sensitive = false
equivalence_classes = { ' \t\r\n', }
substitute_chars = {}
safe_labels = { 's', 'f', 'n', 'u', 't', . . . }
labels = { 's', 'f', 'n', 'j', 'k', . . . }
special_keys = {
  repeat_search = '<enter>',
  next_phase_one_target = '<enter>',
  next_target = {'<enter>', ';'},
  prev_target = {'<tab>', ','},
  next_group = '<space>',
  prev_group = '<tab>',
  multi_accept = '<enter>',
  multi_revert = '<backspace>',
}

Mappings

See :h leap-default-mappings. To define alternative mappings, you can use the <Plug> keys listed at :h leap-custom-mappings.

Note: To create custom motions, see Extending Leap below.

Highlight groups

For customizing the highlight colors, see :h leap-highlight.

In case you - as a user - are not happy with a certain colorscheme's integration, you could force reloading the default settings by calling leap.init_highlight(true). The call can even be wrapped in an autocommand to automatically re-init on every colorscheme change:

autocmd ColorScheme * lua require('leap').init_highlight(true)

This can be tweaked further, you could e.g. check the actual colorscheme, and only execute for certain ones, etc.

Extending Leap

There is more to Leap than meets the eye. On a general level, you should think of it as less of a motion plugin and more of an engine for selecting visible targets on the screen (acquired by arbitrary means), and doing arbitrary things with them.

There are lots of ways you can extend the plugin and bend it to your will, and the combinations of them give you almost infinite possibilities.

Calling `leap` with custom arguments

Instead of using the provided <Plug> keys, you can also call the leap function directly. The following arguments are available:

opts: A table just like leap.opts, to override any default setting for the specific call. E.g.:

require('leap').leap { opts = { labels = {} } }

offset: Where to land with the cursor compared to the target position (-1, 0, 1, 2).

inclusive_op: A flag indicating whether an operation should behave as inclusive (:h inclusive).

backward: Search backward instead of forward in the current window.

target_windows: A list of windows (as winids) to be searched.

-- Bidirectional search in the current window is just a specific case of the
-- multi-window mode.
require('leap').leap { target_windows = { vim.fn.win_getid() } }

-- Searching in all windows (including the current one) on the tab page.
require('leap').leap { target_windows = vim.tbl_filter(
  function (win) return vim.api.nvim_win_get_config(win).focusable end,
  vim.api.nvim_tabpage_list_wins(0)
)}

This is where things start to become really interesting:

targets: Either a list of targets, or a function returning such a list. The elements of the list are tables of arbitrary structure, with the only mandatory field being pos - a (1,1)-indexed tuple; this is the position of the label, and also the jump target, if there is no custom action provided. If you have targets in multiple windows, you also need to provide a wininfo field for each (:h getwininfo()). Targets can represent anything with a position, like Tree-sitter nodes, etc.

local function get_line_starts(winid)
  local wininfo =  vim.fn.getwininfo(winid)[1]
  local cur_line = vim.fn.line('.')

  -- Get targets.
  local targets = {}
  local lnum = wininfo.topline
  while lnum <= wininfo.botline do
    local fold_end = vim.fn.foldclosedend(lnum)
    -- Skip folded ranges.
    if fold_end ~= -1 then
      lnum = fold_end + 1
    else
      if lnum ~= cur_line then table.insert(targets, { pos = { lnum, 1 } }) end
      lnum = lnum + 1
    end
  end
  -- Sort them by vertical screen distance from cursor.
  local cur_screen_row = vim.fn.screenpos(winid, cur_line, 1)['row']
  local function screen_rows_from_cur(t)
    local t_screen_row = vim.fn.screenpos(winid, t.pos[1], t.pos[2])['row']
    return math.abs(cur_screen_row - t_screen_row)
  end
  table.sort(targets, function (t1, t2)
    return screen_rows_from_cur(t1) < screen_rows_from_cur(t2)
  end)

  if #targets >= 1 then
    return targets
  end
end

-- Usage:
local function leap_to_line()
  winid = vim.api.nvim_get_current_win()
  require('leap').leap {
    target_windows = { winid },
    targets = get_line_starts(winid),
  }
end

action: A Lua function that will be executed by Leap in place of the jump. (You could obviously implement some custom jump logic here too.) Its only argument is either a target, or a list of targets (in multiselect mode).

function leap_to_window()
  target_windows = require('leap.util').get_enterable_windows()
  local targets = {}
  for _, win in ipairs(target_windows) do
    local wininfo = vim.fn.getwininfo(win)[1]
    local pos = { wininfo.topline, 1 }  -- top/left corner
    table.insert(targets, { pos = pos, wininfo = wininfo })
  end

  require('leap').leap {
    target_windows = target_windows,
    targets = targets,
    action = function (target)
      vim.api.nvim_set_current_win(target.wininfo.winid)
    end
  }
end

multiselect: A flag allowing for selecting multiple targets for action. In this mode, you can just start picking labels one after the other. You can revert the most recent pick with <backspace>, and accept the selection with <enter>.

-- The following example showcases a custom action, using `multiselect`. We're
-- executing a `normal!` command at each selected position (this could be even
-- more useful if we'd pass in custom targets too).

function paranormal(targets)
  -- Get the :normal sequence to be executed.
  local input = vim.fn.input("normal! ")
  if #input < 1 then return end

  local ns = vim.api.nvim_create_namespace("")

  -- Set an extmark as an anchor for each target, so that we can also execute
  -- commands that modify the positions of other targets (insert/change/delete).
  for _, target in ipairs(targets) do
    local line, col = unpack(target.pos)
    id = vim.api.nvim_buf_set_extmark(0, ns, line - 1, col - 1, {})
    target.extmark_id = id
  end

  -- Jump to each extmark (anchored to the "moving" targets), and execute the
  -- command sequence.
  for _, target in ipairs(targets) do
    local id = target.extmark_id
    local pos = vim.api.nvim_buf_get_extmark_by_id(0, ns, id, {})
    vim.fn.cursor(pos[1] + 1, pos[2] + 1)
    vim.cmd("normal! " .. input)
  end

  -- Clean up the extmarks.
  vim.api.nvim_buf_clear_namespace(0, ns, 0, -1)
end

-- Usage:
require('leap').leap {
    target_windows = { vim.fn.win_getid() },
    action = paranormal,
    multiselect = true,
}

Accessing the arguments passed to `leap`

The arguments of the current call are always available at runtime, in the state.args table.

Setting up autocommands

Leap triggers User events on entering/exiting (with patterns LeapEnter and LeapLeave), so that you can set up autocommands, e.g. to change the values of some editor options while the plugin is active (:h leap-events).

Customizing specific invocations

Using autocommands together with the args table, you can customize practically anything on a per-call basis - keep in mind that nothing prevents you from passing arbitrary flags when calling leap:

function my_custom_leap_func()
    require('leap').leap { my_custom_flag = true, ... }
end

vim.api.nvim_create_autocmd('User', {
  pattern = 'LeapEnter',
  callback = function ()
    if require('leap').state.args.my_custom_flag then
      -- Implement some special logic here, that will only apply to
      -- my_custom_leap_func() (e.g., change the style of the labels),
      -- and clean up with an analogous `LeapLeave` autocommand.
    end
  end
})

Plugins using Leap

leap-spooky.nvim (remote operations on text objects)
flit.nvim (enhanced f/t motions)
leap-ast.nvim (Tree-sitter nodes)

neovimcraft

neovimcraft

ggandor/leap.nvim

CREATED

2022-03-13

UPDATED

16 days ago

leap.nvim

How to use it (TL;DR)

Why is this method cool?

Down the kangaroo hole

Design considerations in detail

The ideal

How do we measure up?

Auxiliary principles

Background

Status

FAQ

Getting started

Requirements

Dependencies

Installation

Usage

Special cases and additional features

Resolving highlighting conflicts in phase one

Cross-window motions

Visual and Operator-pending mode

Jumping to the end of the line and to empty lines

Repeat and traversal

Tips

Smart autojump

Configuration

Mappings

Highlight groups

Extending Leap

Calling leap with custom arguments

Accessing the arguments passed to leap

Setting up autocommands

Customizing specific invocations

Plugins using Leap

Calling `leap` with custom arguments

Accessing the arguments passed to `leap`