--- *mini.ai* Extend and create a/i textobjects

--- *MiniAi*

---

--- MIT License Copyright (c) 2022 Evgeni Chasnovski

---

--- ==============================================================================

---

--- Enhance some builtin |text-objects| (like |a(|, |a)|, |a'|, and more),

--- create new ones (like `a*`, `a<Space>`, `af`, `a?`, and more), and allow

--- user to create their own.

---

--- Features:

--- - Customizable creation of `a`/`i` textobjects using Lua patterns and functions.

--- Supports:

--- - Dot-repeat.

--- - |v:count|.

--- - Different search methods (see |MiniAi.config|).

--- - Consecutive application (update selection without leaving Visual mode).

--- - Aliases for multiple textobjects.

---

--- - Comprehensive builtin textobjects (see more in |MiniAi-textobject-builtin|):

--- - Balanced brackets (with and without whitespace) plus alias.

--- - Balanced quotes plus alias.

--- - Function call.

--- - Argument.

--- - Tag.

--- - Derived from user prompt.

--- - Default for punctuation, digit, space, or tab.

---

--- - Motions for jumping to left/right edge of textobject.

---

--- - Set of specification generators to tweak some builtin textobjects (see

--- |MiniAi.gen_spec|).

---

--- - Treesitter textobjects (through |MiniAi.gen_spec.treesitter()| helper).

---

--- This module works by defining mappings for both `a` and `i` in Visual and

--- Operator-pending mode. After typing, they wait for single character user input

--- treated as textobject identifier and apply resolved textobject specification

--- (fall back to other mappings if can't find proper textobject id). For more

--- information see |MiniAi-textobject-specification| and |MiniAi-algorithm|.

---

--- Known issues which won't be resolved:

--- - Search for builtin textobjects is done mostly using Lua patterns

--- (regex-like approach). Certain amount of false positives is to be expected.

---

--- - During search for builtin textobjects there is no distinction if it is

--- inside string or comment. For example, in the following case there will

--- be wrong match for a function call: `f(a = ")", b = 1)`.

---

--- General rule of thumb: any instrument using available parser for document

--- structure (like treesitter) will usually provide more precise results. This

--- module has builtins mostly for plain text textobjects which are useful

--- most of the times (like "inside brackets", "around quotes/underscore", etc.).

--- For advanced use cases define function specification for custom textobjects.

---

--- What it doesn't (and probably won't) do:

--- - Have special operators to specially handle whitespace (like `I` and `A`

--- in 'targets.vim'). Whitespace handling is assumed to be done inside

--- textobject specification (like `i(` and `i)` handle whitespace differently).

---

--- # Setup ~

---

--- This module needs a setup with `require('mini.ai').setup({})` (replace

--- `{}` with your `config` table). It will create global Lua table `MiniAi`

--- which you can use for scripting or manually (with `:lua MiniAi.*`).

---

--- See |MiniAi.config| for available config settings.

---

--- You can override runtime config settings (like `config.custom_textobjects`)

--- locally to buffer inside `vim.b.miniai_config` which should have same structure

--- as `MiniAi.config`. See |mini.nvim-buffer-local-config| for more details.

---

--- To stop module from showing non-error feedback, set `config.silent = true`.

---

--- # Comparisons ~

---

--- - 'wellle/targets.vim':

--- - Has limited support for creating own textobjects: it is constrained

--- to pre-defined detection rules. 'mini.ai' allows creating own rules

--- via Lua patterns and functions (see |MiniAi-textobject-specification|).

--- - Doesn't provide any programmatical API for getting information about

--- textobjects. 'mini.ai' does it via |MiniAi.find_textobject()|.

--- - Has no implementation of "moving to edge of textobject". 'mini.ai'

--- does it via |MiniAi.move_cursor()| and `g[` and `g]` default mappings.

--- - Has elaborate ways to control searching of the next textobject.

--- 'mini.ai' relies on handful of 'config.search_method'.

--- - Implements `A`, `I` operators. 'mini.ai' does not by design: it is

--- assumed to be a property of textobject, not operator.

--- - Doesn't implement "function call" and "user prompt" textobjects.

--- 'mini.ai' does (with `f` and `?` identifiers).

--- - Has limited support for "argument" textobject. Although it works in

--- most situations, it often misdetects commas as argument separator

--- (like if it is inside quotes or `{}`). 'mini.ai' deals with these cases.

--- - 'nvim-treesitter/nvim-treesitter-textobjects':

--- - Along with textobject functionality provides a curated and maintained

--- set of popular textobject queries for many languages (which can power

--- |MiniAi.gen_spec.treesitter()| functionality).

--- - Operates with custom treesitter directives (see

--- |lua-treesitter-directives|) allowing more fine-tuned textobjects.

--- - Implements only textobjects based on treesitter.

--- - Doesn't support |v:count|.

--- - Doesn't support multiple search method (basically, only 'cover').

--- - Doesn't support consecutive application of target textobject.

---

--- # Disabling ~

---

--- To disable, set `vim.g.miniai_disable` (globally) or `vim.b.miniai_disable`

--- (for a buffer) to `true`. Considering high number of different scenarios

--- and customization intentions, writing exact rules for disabling module's

--- functionality is left to user. See |mini.nvim-disabling-recipes| for common

--- recipes.

--- Builtin textobjects ~

---

--- This table describes all builtin textobjects along with what they

--- represent. Explanation:

--- - `Key` represents the textobject identifier: single alphanumeric,

--- punctuation, space, or tab character which should be typed after `a`/`i`.

--- - `Name` is a description of textobject.

--- - `Example line` contains a string for which examples are constructed. The

--- `*` denotes the cursor position.

--- - `a`/`i` describe inclusive region representing `a` and `i` textobjects.

--- Use numbers in separators for easier navigation.

--- - `2a`/`2i` describe either `2a`/`2i` (support for |v:count|) textobjects

--- or `a`/`i` textobject followed by another `a`/`i` textobject (consecutive

--- application leads to incremental selection).

---

--- Example: typing `va)` with cursor on `*` leads to selection from column 2

--- to column 12. Another typing `a)` changes selection to [1; 13]. Also, besides

--- visual selection, any |operator| can be used or `g[`/`g]` motions to move

--- to left/right edge of `a` textobject.

--- >

--- |Key| Name | Example line | a | i | 2a | 2i |

--- |---|---------------|-1234567890123456-|--------|--------|--------|--------|

--- | ( | Balanced () | (( *a (bb) )) | | | | |

--- | [ | Balanced [] | [[ *a [bb] ]] | [2;12] | [4;10] | [1;13] | [2;12] |

--- | { | Balanced {} | {{ *a {bb} }} | | | | |

--- | < | Balanced <> | << *a <bb> >> | | | | |

--- |---|---------------|-1234567890123456-|--------|--------|--------|--------|

--- | ) | Balanced () | (( *a (bb) )) | | | | |

--- | ] | Balanced [] | [[ *a [bb] ]] | | | | |

--- | } | Balanced {} | {{ *a {bb} }} | [2;12] | [3;11] | [1;13] | [2;12] |

--- | > | Balanced <> | << *a <bb> >> | | | | |

--- | b | Alias for | [( *a {bb} )] | | | | |

--- | | ), ], or } | | | | | |

--- |---|---------------|-1234567890123456-|--------|--------|--------|--------|

--- | " | Balanced " | "*a" " bb " | | | | |

--- | ' | Balanced ' | '*a' ' bb ' | | | | |

--- | ` | Balanced ` | `*a` ` bb ` | [1;4] | [2;3] | [6;11] | [7;10] |

--- | q | Alias for | '*a' " bb " | | | | |

--- | | ", ', or ` | | | | | |

--- |---|---------------|-1234567890123456-|--------|--------|--------|--------|

--- | ? | User prompt | e*e o e o o | [3;5] | [4;4] | [7;9] | [8;8] |

--- | |(typed e and o)| | | | | |

--- |---|---------------|-1234567890123456-|--------|--------|--------|--------|

--- | t | Tag | <x><y>*a</y></x> | [4;12] | [7;8] | [1;16] | [4;12] |

--- |---|---------------|-1234567890123456-|--------|--------|--------|--------|

--- | f | Function call | f(a, g(*b, c) ) | [6;13] | [8;12] | [1;15] | [3;14] |

--- |---|---------------|-1234567890123456-|--------|--------|--------|--------|

--- | a | Argument | f(*a, g(b, c) ) | [3;5] | [3;4] | [5;14] | [7;13] |

--- |---|---------------|-1234567890123456-|--------|--------|--------|--------|

--- | | Default | | | | | |

--- | | (digits, | aa_*b__cc___ | [4;7] | [4;5] | [8;12] | [8;9] |

--- | | punctuation, | (example for _) | | | | |

--- | | or whitespace)| | | | | |

--- |---|---------------|-1234567890123456-|--------|--------|--------|--------|

--- <

--- Notes:

--- - All examples assume default `config.search_method`.

--- - Open brackets differ from close brackets by how they treat inner edge

--- whitespace for `i` textobject: open ignores it, close - includes.

--- - Default textobject is activated for identifiers from digits (0, ..., 9),

--- punctuation (like `_`, `*`, `,`, etc.), whitespace (space, tab, etc.).

--- They are designed to be treated as separators, so include only right edge

--- in `a` textobject. To include both edges, use custom textobjects

--- (see |MiniAi-textobject-specification| and |MiniAi.config|).

---@tag MiniAi-textobject-builtin

--- - REGION - table representing region in a buffer. Fields:

--- - <from> and <to> for inclusive start and end positions (<to> might be

--- `nil` to describe empty region). Each position is also a table with

--- line <line> and column <col> (both start at 1).

--- - <vis_mode> for which Visual mode will be used to select textobject.

--- See `opts` argument of |MiniAi.select_textobject()|.

--- One of `'v'`, `'V'`, `'\22'` (escaped `'<C-v>'`).

--- Examples:

--- - `{ from = { line = 1, col = 1 }, to = { line = 2, col = 1 } }`

--- - Force linewise mode: >

--- {

--- from = { line = 1, col = 1 }, to = { line = 2, col = 1 },

--- vis_mode = 'V',

--- }

--- < - Empty region: `{ from = { line = 10, col = 10 } }`

--- - PATTERN - string describing Lua pattern.

--- - SPAN - interval inside a string (end-exclusive). Like [1, 5). Equal

--- `from` and `to` edges describe empty span at that point.

--- - SPAN `A = [a1, a2)` COVERS `B = [b1, b2)` if every element of

--- `B` is within `A` (`a1 <= b < a2`).

--- It also is described as B IS NESTED INSIDE A.

--- - NESTED PATTERN - array of patterns aimed to describe nested spans.

--- - SPAN MATCHES NESTED PATTERN if there is a sequence of consecutively

--- nested spans each matching corresponding pattern within substring of

--- previous span (or input string for first span). Example:

--- Nested patterns: `{ '%b()', '^. .* .$' }` (balanced `()` with inner space)

--- Input string: `( ( () ( ) ) )`

--- `123456789012345`

--- Here are all matching spans [1, 15) and [3, 13). Both [5, 7) and [8, 10)

--- match first pattern but not second. All other combinations of `(` and `)`

--- don't match first pattern (not balanced).

--- - COMPOSED PATTERN: array with each element describing possible pattern

--- (or array of them) at that place. Composed pattern basically defines all

--- possible combinations of nested pattern (their cartesian product).

--- Examples:

--- 1. Composed pattern: `{ { '%b()', '%b[]' }, '^. .* .$' }`

--- Composed pattern expanded into equivalent array of nested patterns:

--- `{ '%b()', '^. .* .$' }` and `{ '%b[]', '^. .* .$' }`

--- Description: either balanced `()` or balanced `[]` but both with

--- inner edge space.

--- 2. Composed pattern:

--- `{ { { '%b()', '^. .* .$' }, { '%b[]', '^.[^ ].*[^ ].$' } }, '.....' }`

--- Composed pattern expanded into equivalent array of nested patterns:

--- `{ '%b()', '^. .* .$', '.....' }` and

--- `{ '%b[]', '^.[^ ].*[^ ].$', '.....' }`

--- Description: either "balanced `()` with inner edge space" or

--- "balanced `[]` with no inner edge space", both with 5 or more characters.

--- - SPAN MATCHES COMPOSED PATTERN if it matches at least one nested pattern

--- from expanded composed pattern.

---@tag MiniAi-glossary

--- Textobject specification has a structure of composed pattern (see

--- |MiniAi-glossary|) with two differences:

--- - Last pattern(s) should have even number of empty capture groups denoting

--- how the last string should be processed to extract `a` or `i` textobject:

--- - Zero captures mean that whole string represents both `a` and `i`.

--- Example: `xxx` will define textobject matching string `xxx` literally.

--- - Two captures represent `i` textobject inside of them. `a` - whole string.

--- Example: `x()x()x` defines `a` textobject to be `xxx`, `i` - middle `x`.

--- - Four captures define `a` textobject inside captures 1 and 4, `i` -

--- inside captures 2 and 3. Example: `x()()x()x()` defines `a`

--- textobject to be last `xx`, `i` - middle `x`.

--- - Allows callable objects (see |vim.is_callable()|) in certain places

--- (enables more complex textobjects in exchange of increase in configuration

--- complexity and computations):

--- - If specification itself is a callable, it will be called with the same

--- arguments as |MiniAi.find_textobject()| and should return one of:

--- - Composed pattern. Useful for implementing user input. Example of

--- simplified variant of textobject for function call with name taken

--- from user prompt: >

---

--- function()

--- local left_edge = vim.pesc(vim.fn.input('Function name: '))

--- return { string.format('%s+%%b()', left_edge), '^.-%(().*()%)$' }

--- end

--- <

--- - Single output region. Useful to allow full control over

--- textobject. Will be taken as is. Example of returning whole buffer: >

---

--- function()

--- local from = { line = 1, col = 1 }

--- local to = {

--- line = vim.fn.line('$'),

--- col = math.max(vim.fn.getline('$'):len(), 1)

--- }

--- return { from = from, to = to, vis_mode = 'V' }

--- end

--- <

--- - Array of output region(s). Useful for incorporating other

--- instruments, like treesitter (see |MiniAi.gen_spec.treesitter()|).

--- The best region will be picked in the same manner as with composed

--- pattern (respecting options `n_lines`, `search_method`, etc.).

--- Example of selecting "best" line with display width more than 80: >

---

--- function(_, _, _)

--- local res = {}

--- for i = 1, vim.api.nvim_buf_line_count(0) do

--- local cur_line = vim.fn.getline(i)

--- if vim.fn.strdisplaywidth(cur_line) > 80 then

--- local region = {

--- from = { line = i, col = 1 },

--- to = { line = i, col = cur_line:len() },

--- }

--- table.insert(res, region)

--- end

--- end

--- return res

--- end

--- <

--- - If there is a callable instead of assumed string pattern, it is expected

--- to have signature `(line, init)` and behave like `pattern:find()`.

--- It should return two numbers representing span in `line` next after

--- or at `init` (`nil` if there is no such span).

--- !IMPORTANT NOTE!: it means that output's `from` shouldn't be strictly

--- to the left of `init` (it will lead to infinite loop). Not allowed as

--- last item (as it should be pattern with captures).

--- Example of matching only balanced parenthesis with big enough width: >

---

--- {

--- '%b()',

--- function(s, init)

--- if init > 1 or s:len() < 5 then return end

--- return 1, s:len()

--- end,

--- '^.().*().$'

--- }

--- <

--- More examples:

--- - See |MiniAi.gen_spec| for function wrappers to create commonly used

--- textobject specifications.

---

--- - Pair of balanced brackets from set (used for builtin `b` identifier):

--- `{ { '%b()', '%b[]', '%b{}' }, '^.().*().$' }`

---

--- - Imitate word ignoring digits and punctuation (supports only Latin alphabet):

--- `{ '()()%f[%w]%w+()[ \t]*()' }`

---

--- - Word with camel case support (also supports only Latin alphabet):

--- `{`

--- `{`

--- `'%u[%l%d]+%f[^%l%d]',`

--- `'%f[%S][%l%d]+%f[^%l%d]',`

--- `'%f[%P][%l%d]+%f[^%l%d]',`

--- `'^[%l%d]+%f[^%l%d]',`

--- `},`

--- `'^().*()$'`

--- `}`

---

--- - Number: `{ '%f[%d]%d+' }`

---

--- - Date in 'YYYY-MM-DD' format: `{ '()%d%d%d%d%-%d%d%-%d%d()' }`

---

--- - Lua block string: `{ '%[%[().-()%]%]' }`

---@tag MiniAi-textobject-specification

--- Algorithm design

---

--- Search for the textobjects relies on these principles:

--- - It uses same input data as described in |MiniAi.find_textobject()|,

--- i.e. whether it is `a` or `i` textobject, its identifier, reference region, etc.

--- - Textobject specification is constructed based on textobject identifier

--- (see |MiniAi-textobject-specification|).

--- - General search is done by converting some 2d buffer region (neighborhood

--- of reference region) into 1d string (each line is appended with `\n`).

--- Then search for a best span matching textobject specification is done

--- inside string (see |MiniAi-glossary|). After that, span is converted back

--- into 2d region. Note: first search is done inside reference region lines,

--- and only after that - inside its neighborhood within `config.n_lines`

--- (see |MiniAi.config|).

--- - The best matching span is chosen by iterating over all spans matching

--- textobject specification and comparing them with "current best".

--- Comparison also depends on reference region (tighter covering is better,

--- otherwise closer is better) and search method (if span is even considered).

--- - Extract span based on extraction pattern (last item in nested pattern).

--- - If task is to perform a consecutive search (`opts.n_times` is greater than 1),

--- steps are repeated with current best match becoming reference region.

--- One such additional step is also done if final region is equal to

--- reference region (this enables consecutive application).

---

--- Notes:

--- - Iteration over all matched spans is done in depth-first fashion with

--- respect to nested pattern.

--- - It is guaranteed that span is compared only once.

--- - For the sake of increasing functionality, during iteration over all

--- matching spans, some Lua patterns in composed pattern are handled

--- specially.

--- - `%bxx` (`xx` is two identical characters). It denotes balanced pair

--- of identical characters and results into "paired" matches. For

--- example, `%b""` for `"aa" "bb"` would match `"aa"` and `"bb"`, but

--- not middle `" "`.

--- - `x.-y` (`x` and `y` are different strings). It results only in matches with

--- smallest width. For example, `e.-o` for `e e o o` will result only in

--- middle `e o`. Note: it has some implications for when parts have

--- quantifiers (like `+`, etc.), which usually can be resolved with

--- frontier pattern `%f[]` (see examples in |MiniAi-textobject-specification|).

---@tag MiniAi-algorithm

-- Module definition ==========================================================

local MiniAi = {}

local H = {}

--- Module setup

---

---@param config table|nil Module config table. See |MiniAi.config|.

---

---@usage `require('mini.ai').setup({})` (replace `{}` with your `config` table)

MiniAi.setup = function(config)

-- Export module

_G.MiniAi = MiniAi

-- Setup config

config = H.setup_config(config)

-- Apply config

H.apply_config(config)

end

--- Module config

---

--- Default values:

---@eval return MiniDoc.afterlines_to_code(MiniDoc.current.eval_section)

---@text # Options ~

---

--- ## Custom textobjects ~

---

--- Each named entry of `config.custom_textobjects` is a textobject with

--- that identifier and specification (see |MiniAi-textobject-specification|).

--- They are also used to override builtin ones (|MiniAi-textobject-builtin|).

--- Supply non-valid input (not in specification format) to disable module's

--- builtin textobject in favor of external or Neovim's builtin mapping.

---

--- Examples:

--- >

--- require('mini.ai').setup({

--- custom_textobjects = {

--- -- Tweak argument textobject

--- a = require('mini.ai').gen_spec.argument({ brackets = { '%b()' } }),

---

--- -- Disable brackets alias in favor of builtin block textobject

--- b = false,

---

--- -- Now `vax` should select `xxx` and `vix` - middle `x`

--- x = { 'x()x()x' },

---

--- -- Whole buffer

--- g = function()

--- local from = { line = 1, col = 1 }

--- local to = {

--- line = vim.fn.line('$'),

--- col = math.max(vim.fn.getline('$'):len(), 1)

--- }

--- return { from = from, to = to }

--- end

--- }

--- })

---

--- -- Use `vim.b.miniai_config` to customize per buffer

--- -- Example of specification useful for Markdown files:

--- local spec_pair = require('mini.ai').gen_spec.pair

--- vim.b.miniai_config = {

--- custom_textobjects = {

--- ['*'] = spec_pair('*', '*', { type = 'greedy' }),

--- ['_'] = spec_pair('_', '_', { type = 'greedy' }),

--- },

--- }

--- <

--- There are more example specifications in |MiniAi-textobject-specification|.

---

--- ## Search method ~

---

--- Value of `config.search_method` defines how best match search is done.

--- Based on its value, one of the following matches will be selected:

--- - Covering match. Left/right edge is before/after left/right edge of

--- reference region.

--- - Previous match. Left/right edge is before left/right edge of reference

--- region.

--- - Next match. Left/right edge is after left/right edge of reference region.

--- - Nearest match. Whichever is closest among previous and next matches.

---

--- Possible values are:

--- - `'cover'` - use only covering match. Don't use either previous or

--- next; report that there is no textobject found.

--- - `'cover_or_next'` (default) - use covering match. If not found, use next.

--- - `'cover_or_prev'` - use covering match. If not found, use previous.

--- - `'cover_or_nearest'` - use covering match. If not found, use nearest.

--- - `'next'` - use next match.

--- - `'prev'` - use previous match.

--- - `'nearest'` - use nearest match.

---

--- Note: search is first performed on the reference region lines and only

--- after failure - on the whole neighborhood defined by `config.n_lines`. This

--- means that with `config.search_method` not equal to `'cover'`, "prev" or

--- "next" textobject will end up as search result if they are found on first

--- stage although covering match might be found in bigger, whole neighborhood.

--- This design is based on observation that most of the time operation is done

--- within reference region lines (usually cursor line).

---

--- Here is an example of what `a)` textobject is based on a value of

--- `'config.search_method'` when cursor is inside `bbb` word:

--- - `'cover'`: `(a) bbb (c)` -> none

--- - `'cover_or_next'`: `(a) bbb (c)` -> `(c)`

--- - `'cover_or_prev'`: `(a) bbb (c)` -> `(a)`

--- - `'cover_or_nearest'`: depends on cursor position.

--- For first and second `b` - as in `cover_or_prev` (as previous match is

--- nearer), for third - as in `cover_or_next` (as next match is nearer).

--- - `'next'`: `(a) bbb (c)` -> `(c)`. Same outcome for `(bbb)`.

--- - `'prev'`: `(a) bbb (c)` -> `(a)`. Same outcome for `(bbb)`.

--- - `'nearest'`: depends on cursor position (same as in `'cover_or_nearest'`).

---

--- ## Mappings ~

---

--- Mappings `around_next`/`inside_next` and `around_last`/`inside_last` are

--- essentially `around`/`inside` but using search method `'next'` and `'prev'`.

MiniAi.config = {

-- Table with textobject id as fields, textobject specification as values.

-- Also use this to disable builtin textobjects. See |MiniAi.config|.

custom_textobjects = nil,

-- Module mappings. Use `''` (empty string) to disable one.

mappings = {

-- Main textobject prefixes

around = 'a',

inside = 'i',

-- Next/last textobjects

around_next = 'an',

inside_next = 'in',

around_last = 'al',

inside_last = 'il',

-- Move cursor to corresponding edge of `a` textobject

goto_left = 'g[',

goto_right = 'g]',

},

-- Number of lines within which textobject is searched

n_lines = 50,

-- How to search for object (first inside current line, then inside

-- neighborhood). One of 'cover', 'cover_or_next', 'cover_or_prev',

-- 'cover_or_nearest', 'next', 'prev', 'nearest'.

search_method = 'cover_or_next',

-- Whether to disable showing non-error feedback

silent = false,

}

--minidoc_afterlines_end

-- Module functionality =======================================================

--- Find textobject region

---

---@param ai_type string One of `'a'` or `'i'`.

---@param id string Single character string representing textobject id. It is

--- used to get specification which is later used to compute textobject region.

--- Note: if specification is a function, it is called with all present

--- arguments (`opts` is populated with default arguments).

---@param opts table|nil Options. Possible fields:

--- - <n_lines> - Number of lines within which textobject is searched.

--- Default: `config.n_lines` (see |MiniAi.config|).

--- - <n_times> - Number of times to perform a consecutive search. Each one

--- is done with reference region being previous found textobject region.

--- Default: 1.

--- - <reference_region> - region to try to cover (see |MiniAi-glossary|). It

--- is guaranteed that output region will not be inside or equal to this one.

--- Default: empty region at cursor position.

--- - <search_method> - Search method. Default: `config.search_method`.

---

---@return table|nil Region of textobject or `nil` if no textobject different

--- from `opts.reference_region` was consecutively found `opts.n_times` times.

MiniAi.find_textobject = function(ai_type, id, opts)

if not (ai_type == 'a' or ai_type == 'i') then H.error([[`ai_type` should be one of 'a' or 'i'.]]) end

opts = vim.tbl_deep_extend('force', H.get_default_opts(), opts or {})

H.validate_search_method(opts.search_method)

-- Get textobject specification

local tobj_spec = H.get_textobject_spec(id, { ai_type, id, opts })

if tobj_spec == nil then return end

if H.is_region(tobj_spec) then return tobj_spec end

-- Find region

local res = H.find_textobject_region(tobj_spec, ai_type, opts)

if res == nil then

local msg = string.format(

[[No textobject %s found covering region%s within %d line%s and `search_method = '%s'`.]],

vim.inspect(ai_type .. id),

opts.n_times == 1 and '' or (' %s times'):format(opts.n_times),

opts.n_lines,

opts.n_lines == 1 and '' or 's',

opts.search_method

)

H.message(msg)

end

return res

end

--- Move cursor to edge of textobject

---

---@param side string One of `'left'` or `'right'`.

---@param ai_type string One of `'a'` or `'i'`.

---@param id string Single character string representing textobject id.

---@param opts table|nil Same as in |MiniAi.find_textobject()|.

--- `opts.n_times` means number of actual jumps (important when cursor

--- already on the potential jump spot).

MiniAi.move_cursor = function(side, ai_type, id, opts)

if not (side == 'left' or side == 'right') then H.error([[`side` should be one of 'left' or 'right'.]]) end

opts = opts or {}

local init_pos = vim.api.nvim_win_get_cursor(0)

-- Compute single textobject first to find out if it would move the cursor.

-- If not, then eventual `n_times` should be bigger by 1 to imitate `n_times`

-- *actual* jumps. This implements consecutive jumps and has logic of "If

-- cursor is strictly inside region, move to its side first".

local new_opts = vim.tbl_deep_extend('force', opts, { n_times = 1 })

local tobj_single = MiniAi.find_textobject(ai_type, id, new_opts)

if tobj_single == nil then return end

local tobj_side = side == 'left' and 'from' or 'to'

-- Allow empty region

tobj_single.to = tobj_single.to or tobj_single.from

new_opts.n_times = opts.n_times or 1

if (init_pos[1] == tobj_single[tobj_side].line) and (init_pos[2] == tobj_single[tobj_side].col - 1) then

new_opts.n_times = new_opts.n_times + 1

end

-- Compute actually needed textobject while avoiding unnecessary computation

-- in a most common usage (`v:count1 == 1`)

local pos = tobj_single[tobj_side]

if new_opts.n_times > 1 then

local tobj = MiniAi.find_textobject(ai_type, id, new_opts)

if tobj == nil then return end

tobj.to = tobj.to or tobj.from

pos = tobj[tobj_side]

end

-- Move cursor and open enough folds

vim.api.nvim_win_set_cursor(0, { pos.line, pos.col - 1 })

vim.cmd('normal! zv')

end

--- Generate common textobject specifications

---

--- This is a table with function elements. Call to actually get specification.

---

--- Example: >

--- local gen_spec = require('mini.ai').gen_spec

--- require('mini.ai').setup({

--- custom_textobjects = {

--- -- Tweak argument to be recognized only inside `()` between `;`

--- a = gen_spec.argument({ brackets = { '%b()' }, separator = ';' }),

---

--- -- Tweak function call to not detect dot in function name

--- f = gen_spec.function_call({ name_pattern = '[%w_]' }),

---

--- -- Function definition (needs treesitter queries with these captures)

--- F = gen_spec.treesitter({ a = '@function.outer', i = '@function.inner' }),

---

--- -- Make `|` select both edges in non-balanced way

--- ['|'] = gen_spec.pair('|', '|', { type = 'non-balanced' }),

--- }

--- })

MiniAi.gen_spec = {}

--- Argument specification

---

--- Argument textobject (has default `a` identifier) is a region inside

--- balanced bracket between allowed not excluded separators. Use this function

--- to tweak how it works.

---

--- Examples:

--- - `argument({ brackets = { '%b()' } })` will search for an argument only

--- inside balanced `()`.

--- - `argument({ separator = '[,;]' })` will treat both `,` and `;` as separators.

--- - `argument({ exclude_regions = { '%b()' } })` will exclude separators

--- which are inside balanced `()` (inside outer brackets).

---

---@param opts table|nil Options. Allowed fields:

--- - <brackets> - array of patterns for outer balanced brackets.

--- Default: `{ '%b()', '%b[]', '%b{}' }` (any `()`, `[]`, or `{}` can

--- enclose arguments).

--- - <separator> - separator pattern. Default: `','`.

--- One of the practical usages of this option is to include whitespace

--- around character to be a part of separator. For example, `'%s*,%s*'`

--- will treat as separator not only ',', but its possible surrounding

--- whitespace. This has both positive and negative effects. On one hand,

--- `daa` executed over the first argument will delete whitespace after

--- first comma, leading to a more expected outcome. On the other hand it

--- is ambiguous which argument is picked when cursor is over whitespace

--- near the character separator.

--- - <exclude_regions> - array with patterns for regions inside which

--- separators will be ignored.

--- Default: `{ '%b""', "%b''", '%b()', '%b[]', '%b{}' }` (separators

--- inside balanced quotes or brackets are ignored).

MiniAi.gen_spec.argument = function(opts)

opts = vim.tbl_deep_extend('force', {

brackets = { '%b()', '%b[]', '%b{}' },

separator = ',',

exclude_regions = { '%b""', "%b''", '%b()', '%b[]', '%b{}' },

}, opts or {})

local brackets, separator, exclude_regions = opts.brackets, opts.separator, opts.exclude_regions

local res = {}

-- Match brackets

res[1] = brackets

-- Match argument with both left and right separators/brackets

res[2] = function(s, init)

-- Cache string separators per spec as they are used multiple times.

-- Storing per spec allows coexistence of several argument specifications.

H.cache.argument_sep_spans = H.cache.argument_sep_spans or {}

H.cache.argument_sep_spans[res] = H.cache.argument_sep_spans[res] or {}

local sep_spans = H.cache.argument_sep_spans[res][s] or H.arg_get_separator_spans(s, separator, exclude_regions)

H.cache.argument_sep_spans[res][s] = sep_spans

-- Return span fully on right of `init`, `nil` otherwise

-- For first argument returns left bracket; for last - right one.

for i = 1, #sep_spans - 1 do

if init <= sep_spans[i][1] then return sep_spans[i][1], sep_spans[i + 1][2] end

end

return nil

end

-- Make extraction part

--

-- Extraction of `a` type depends on argument number, `i` - as `a` but

-- without separators and inner whitespace. The reason for this complex

-- solution are the following requirements:

-- - Don't match argument region when cursor is on the outer bracket.

-- Example: `f(xxx)` should select argument only when cursor is on 'x'.

-- - Don't select edge whitespace for first and last argument BUT MATCH WHEN

-- CURSOR IS ON THEM which needs to match edge whitespace right until the

-- extraction part. This is useful when working with padded brackets.

-- Example for `f( xx , yy )`:

-- - `a` object should select 'xx ,' when cursor is on all ' xx ';

-- should select ', yy' when cursor is on all ' yy '.

-- - `i` object should select 'xx' when cursor is on all ' xx ';

-- should select 'yy' when cursor is on all ' yy '.

--

-- At this stage whether argument is first, middle, last, or single is

-- determined by presence of matching separator at either left or right edge.

-- If edge matches separator pattern - it has separator. If not - a bracket.

local left_edge_separator = '^' .. separator

local find_after_left_separator = function(s)

local _, sep_end = s:find(left_edge_separator)

if sep_end == nil then return nil end

return sep_end + 1

end

local find_after_left_bracket = function(s)

local left_sep = find_after_left_separator(s)

if left_sep ~= nil then return nil end

return 2

end

local right_edge_sep = separator .. '$'

local find_before_right_separator = function(s)

local sep_start, _ = s:find(right_edge_sep)

if sep_start == nil then return nil end

return sep_start - 1

end

local find_before_right_bracket = function(s)

local right_sep = find_before_right_separator(s)

if right_sep ~= nil then return nil end

return s:len() - 1

end

local match_and_include = function(left_type, left_include, right_type, right_include)

local find_after_left = left_type == 'bracket' and find_after_left_bracket or find_after_left_separator

local find_before_right = right_type == 'bracket' and find_before_right_bracket or find_before_right_separator

return function(s, init)

-- Match only once

if init > 1 then return nil end

-- Make sure that string matches left and right targets

local left_after, right_before = find_after_left(s), find_before_right(s)

if left_after == nil or right_before == nil then return nil end

-- Possibly include matched edge targets

local left = left_include and 1 or left_after

local right = right_include and s:len() or right_before

return left, right

end

end

local extract_first_arg = '^%s*()().-()%s*' .. separator .. '()$'

local extract_nonfirst_arg = '^()' .. separator .. '%s*().-()()%s*$'

local extract_single_arg = '^%s*().-()%s*$'

res[3] = {

-- First argument. Include right separator, exclude left whitespace.

{ match_and_include('bracket', false, 'separator', true), extract_first_arg },

-- Middle argument. Include only left separator.

{ match_and_include('separator', true, 'separator', false), extract_nonfirst_arg },

-- Last argument. Include left separator, exclude right whitespace.

-- NOTE: it misbehaves for whitespace argument. It's OK because it's rare.

{ match_and_include('separator', true, 'bracket', false), extract_nonfirst_arg },

-- Single argument. Include both whitespace (makes `aa` and `ia` differ).

{ match_and_include('bracket', false, 'bracket', false), extract_single_arg },

}

return res

end

--- Function call specification

---

--- Function call textobject (has default `f` identifier) is a region with some

--- characters followed by balanced `()`. Use this function to tweak how it works.

---

--- Example:

--- - `function_call({ name_pattern = '[%w_]' })` will recognize function name with

--- only alphanumeric or underscore (not dot).

---

---@param opts table|nil Optsion. Allowed fields:

--- - <name_pattern> - string pattern of character set allowed in function name.

--- Default: `'[%w_%.]'` (alphanumeric, underscore, or dot).

--- Note: should be enclosed in `[]`.

MiniAi.gen_spec.function_call = function(opts)

opts = vim.tbl_deep_extend('force', { name_pattern = '[%w_%.]' }, opts or {})

-- Use frontier pattern to select widest possible name

return { '%f' .. opts.name_pattern .. opts.name_pattern .. '+%b()', '^.-%(().*()%)$' }

end

--- Pair specification

---

--- Use it to define textobject for region surrounded with `left` from left and

--- `right` from right. The `a` textobject includes both edges, `i` - excludes them.

---

--- Region can be one of several types (controlled with `opts.type`). All

--- examples are for default search method, `a` textobject, and use `'_'` as

--- both `left` and `right`:

--- - Non-balanced (`{ type = 'non-balanced' }`), default. Equivalent to using

--- `x.-y` as first pattern. Example: on line '_a_b_c_' it consecutively

--- matches '_a_', '_b_', '_c_'.

--- - Balanced (`{ type = 'balanced' }`). Equivalent to using `%bxy` as first

--- pattern. Example: on line '_a_b_c_' it consecutively matches '_a_', '_c_'.

--- Note: both `left` and `right` should be single character.

--- - Greedy (`{ type = 'greedy' }`). Like non-balanced but will select maximum

--- consecutive `left` and `right` edges. Example: on line '__a__b_' it

--- consecutively selects '__a__' and '__b_'. Note: both `left` and `right`

--- should be single character.

---

---@param left string Left edge.

---@param right string Right edge.

---@param opts table|nil Options. Possible fields:

--- - <type> - Type of a pair. One of `'non-balanced'` (default), `'balanced'`,

--- `'greedy'`.

MiniAi.gen_spec.pair = function(left, right, opts)

if not (type(left) == 'string' and type(right) == 'string') then

H.error('Both `left` and `right` should be strings.')

end

opts = vim.tbl_deep_extend('force', { type = 'non-balanced' }, opts or {})

if (opts.type == 'balanced' or opts.type == 'greedy') and not (left:len() == 1 and right:len() == 1) then

local msg =

string.format([[Both `left` and `right` should be single character for `opts.type == '%s'`.]], opts.type)

H.error(msg)

end

local left_esc = vim.pesc(left)

local right_esc = vim.pesc(right)

if opts.type == 'balanced' then return { string.format('%%b%s%s', left, right), '^.().*().$' } end

if opts.type == 'non-balanced' then return { string.format('%s().-()%s', left_esc, right_esc) } end

if opts.type == 'greedy' then

return { string.format('%%f[%s]%s+()[^%s]-()%s+%%f[^%s]', left_esc, left_esc, left_esc, right_esc, right_esc) }

end

H.error([[`opts.type` should be one of 'balanced', 'non-balanced', 'greedy'.]])

end

--- Treesitter specification

---

--- This is a specification in function form. When called with a pair of

--- treesitter captures, it returns a specification function outputting an

--- array of regions that match corresponding (`a` or `i`) capture.

---

--- In order for this to work, apart from working treesitter parser for desired

--- language, user should have a reachable language-specific 'textobjects'

--- query (see |vim.treesitter.query.get()| or |get_query()|, depending on your

--- Neovim version).

--- The most straightforward way for this is to have 'textobjects.scm' query

--- file with treesitter captures stored in some recognized path. This is

--- primarily designed to be compatible with plugin

--- 'nvim-treesitter/nvim-treesitter-textobjects', but can be used without it.

---

--- Two most common approaches for having a query file:

--- - Install 'nvim-treesitter/nvim-treesitter-textobjects'. It has curated and

--- well maintained builtin query files for many languages with a standardized

--- capture names, like `function.outer`, `function.inner`, etc.

--- - Manually create file 'after/queries/<language name>/textobjects.scm' in

--- your |$XDG_CONFIG_HOME| directory. It should contain queries with

--- captures (later used to define textobjects). See |lua-treesitter-query|.

--- To verify that query file is reachable, run (example for "lua" language)

--- `:lua print(vim.inspect(vim.treesitter.query.get_files('lua', 'textobjects')))`

--- (output should have at least an intended file).

---

--- Example configuration for function definition textobject with

--- 'nvim-treesitter/nvim-treesitter-textobjects' captures:

--- >

--- local spec_treesitter = require('mini.ai').gen_spec.treesitter

--- require('mini.ai').setup({

--- custom_textobjects = {

--- F = spec_treesitter({ a = '@function.outer', i = '@function.inner' }),

--- o = spec_treesitter({

--- a = { '@conditional.outer', '@loop.outer' },

--- i = { '@conditional.inner', '@loop.inner' },

--- })

--- }

--- })

--- <

--- Notes:

--- - By default query is done using 'nvim-treesitter' plugin if it is present

--- (falls back to builtin methods otherwise). This allows for a more

--- advanced features (like multiple buffer languages, custom directives, etc.).

--- See `opts.use_nvim_treesitter` for how to disable this.

--- - It uses buffer's |filetype| to determine query language.

--- - On large files it is slower than pattern-based textobjects. Still very

--- fast though (one search should be magnitude of milliseconds or tens of

--- milliseconds on really large file).

---

---@param ai_captures table Captures for `a` and `i` textobjects: table with

--- <a> and <i> fields with captures for `a` and `i` textobjects respectively.

--- Each value can be either a string capture (should start with `'@'`) or an

--- array of such captures (best among all matches will be chosen).

---@param opts table|nil Options. Possible values:

--- - <use_nvim_treesitter> - whether to try to use 'nvim-treesitter' plugin

--- (if present) to do the query. It implements more advanced behavior at

--- cost of increased execution time. Provides more coherent experience if

--- 'nvim-treesitter-textobjects' queries are used. Default: `true`.

---

---@return function Function with |MiniAi.find_textobject()| signature which

--- returns array of current buffer regions representing matches for

--- corresponding (`a` or `i`) treesitter capture.

---

---@seealso |MiniAi-textobject-specification| for how this type of textobject

--- specification is processed.

--- |get_query()| for how query is fetched in case of no 'nvim-treesitter'.

--- |Query:iter_captures()| for how all query captures are iterated in case of

--- no 'nvim-treesitter'.

MiniAi.gen_spec.treesitter = function(ai_captures, opts)

opts = vim.tbl_deep_extend('force', { use_nvim_treesitter = true }, opts or {})

ai_captures = H.prepare_ai_captures(ai_captures)

return function(ai_type, _, _)

-- Get array of matched treesitter nodes

local target_captures = ai_captures[ai_type]

local has_nvim_treesitter = pcall(require, 'nvim-treesitter') and pcall(require, 'nvim-treesitter.query')

local node_querier = (has_nvim_treesitter and opts.use_nvim_treesitter) and H.get_matched_nodes_plugin

or H.get_matched_nodes_builtin

local matched_nodes = node_querier(target_captures)

-- Return array of regions

return vim.tbl_map(function(node)

local line_from, col_from, line_to, col_to = node:range()

-- `node:range()` returns 0-based numbers for end-exclusive region

return { from = { line = line_from + 1, col = col_from + 1 }, to = { line = line_to + 1, col = col_to } }

end, matched_nodes)

end

end

--- Visually select textobject region

---

--- Does nothing if no region is found.

---

---@param ai_type string One of `'a'` or `'i'`.

---@param id string Single character string representing textobject id.

---@param opts table|nil Same as in |MiniAi.find_textobject()|. Extra fields:

--- - <vis_mode> - One of `'v'`, `'V'`, or `'\22'` (escaped version of `'<C-v>'`).

--- Default: Latest visual mode.

--- - <operator_pending> - Whether selection is for Operator-pending mode.

--- Used in that mode's mappings, shouldn't be used directly. Default: `false`.

MiniAi.select_textobject = function(ai_type, id, opts)

if H.is_disabled() then return end

opts = opts or {}

-- Exit to Normal before getting textobject id. This way invalid id doesn't

-- result into staying in current mode (which seems to be more convenient).

H.exit_to_normal_mode()

local tobj = MiniAi.find_textobject(ai_type, id, opts)

if tobj == nil then return end

local set_cursor = function(position) vim.api.nvim_win_set_cursor(0, { position.line, position.col - 1 }) end

-- Allow empty regions

local tobj_is_empty = tobj.to == nil

tobj.to = tobj.to or tobj.from

-- Compute selection type preferring the one coming from textobject

local vis_mode = tobj.vis_mode

if vis_mode == nil or not H.is_visual_mode(vis_mode) then

local prev_vis_mode = vim.fn.visualmode()

prev_vis_mode = prev_vis_mode == '' and 'v' or prev_vis_mode

vis_mode = opts.vis_mode and vim.api.nvim_replace_termcodes(opts.vis_mode, true, true, true) or prev_vis_mode

end

-- Allow going past end of line in order to collapse multiline regions

local cache_virtualedit = vim.o.virtualedit

local cache_eventignore = vim.o.eventignore

pcall(function()

-- Do nothing in Operator-pending mode for empty region (except `c`, `d`,

-- or "replace" from 'mini.operators'). These are hand picked because they

-- completely remove selected text, which is necessary for currently only

-- possible empty region selection implementation.

local is_empty_opending = tobj_is_empty and opts.operator_pending

local is_minioperators_replace = vim.v.operator == 'g@' and vim.o.operatorfunc:find('MiniOperators%.replace') ~= nil

local is_allowed_empty_opending = vim.v.operator == 'c' or vim.v.operator == 'd' or is_minioperators_replace

if is_empty_opending and not is_allowed_empty_opending then

H.message('Textobject region is empty. Nothing is done.')

return

end