Merge pull request #14 from julienvincent/feat/form-update-api

feat: form/cursor api

README.md

@@ -69,15 +69,15 @@ require("nvim-paredit").setup({
     ["<localleader>o"] = { paredit.api.raise_form, "Raise form" },
     ["<localleader>O"] = { paredit.api.raise_element, "Raise element" },
 
-    ["E"] = { 
+    ["E"] = {
       paredit.api.move_to_next_element,
       "Jump to next element tail",
       -- by default all keybindings are dot repeatable
       repeatable = false,
       mode = { "n", "x", "o", "v" },
     },
     ["B"] = {
-      paredit.api.move_to_prev_element, 
+      paredit.api.move_to_prev_element,
       "Jump to previous element head",
       repeatable = false,
       mode = { "n", "x", "o", "v" },
@@ -180,6 +180,73 @@ paredit.api.slurp_forwards()
 - **`move_to_next_element`**
 - **`move_to_prev_element`**
 
+Form/element wrap api is in `paredit.wrap` module:
+
+- **`wrap_element_under_cursor`** - accepts prefix and suffix, returns wrapped `TSNode`
+- **`wrap_enclosing_form_under_cursor`** - accepts prefix and suffix, returns wrapped `TSNode`
+
+Cursor api `paredit.cursor`
+
+- **`place_cursor`** - accepts `TSNode`, and following options:
+  - `placement` - enumeration `left_edge`,`inner_start`,`inner_end`,`right_edge`
+  - `mode` - currently only `insert` is supported, defaults to `normal`
+
+## API usage recipes
+
+### `vim-sexp` wrap form (head/tail) replication
+
+Require api module:
+```lua
+local paredit = require("nvim-paredit.api")
+```
+Add following keybindings to config:
+```lua
+["<localleader>w"] = {
+  function()
+    -- place cursor and set mode to `insert`
+    paredit.cursor.place_cursor(
+      -- wrap element under cursor with `( ` and `)`
+      paredit.wrap.wrap_element_under_cursor("( ", ")"),
+      -- cursor placement opts
+      { placement = "inner_start", mode = "insert" }
+    )
+  end,
+  "Wrap element insert head",
+},
+
+["<localleader>W"] = {
+  function()
+    paredit.cursor.place_cursor(
+      paredit.wrap.wrap_element_under_cursor("(", ")"),
+      { placement = "inner_end", mode = "insert" }
+    )
+  end,
+  "Wrap element insert tail",
+},
+
+-- same as above but for enclosing form
+["<localleader>i"] = {
+  function()
+    paredit.cursor.place_cursor(
+      paredit.wrap.wrap_enclosing_form_under_cursor("( ", ")"),
+      { placement = "inner_start", mode = "insert" }
+    )
+  end,
+  "Wrap form insert head",
+},
+
+["<localleader>I"] = {
+  function()
+    paredit.cursor.place_cursor(
+      paredit.wrap.wrap_enclosing_form_under_cursor("(", ")"),
+      { placement = "inner_end", mode = "insert" }
+    )
+  end,
+  "Wrap form insert tail",
+}
+```
+Same approach can be used for other `vim-sexp` keybindings (e.g. `<localleader>e[`) with cursor placement or without.
+
 ## Prior Art
 
 ### [vim-sexp](https://github.com/guns/vim-sexp)
@@ -188,10 +255,10 @@ Currently the de-facto s-expression editing plugin with the most extensive set o
 
 The main reasons you might want to consider `nvim-paredit` instead are:
 
-+ Easier configuration and an exposed lua API
-+ Control over how the cursor is moved during slurp/barf. (For example if you don't want the cursor to always be moved)
-+ Recursive slurp/barf operations. If your cursor is in a nested form you can still slurp from the forms parent(s)
-+ Subjectively better out-of-the-box keybindings
+- Easier configuration and an exposed lua API
+- Control over how the cursor is moved during slurp/barf. (For example if you don't want the cursor to always be moved)
+- Recursive slurp/barf operations. If your cursor is in a nested form you can still slurp from the forms parent(s)
+- Subjectively better out-of-the-box keybindings
 
 ### [vim-sexp-mappings-for-regular-people](https://github.com/tpope/vim-sexp-mappings-for-regular-people)
 

lua/nvim-paredit/api/cursor.lua

@@ -0,0 +1,30 @@
+local M = {}
+
+function M.insert_mode()
+  vim.api.nvim_feedkeys("i", "n", true)
+end
+
+function M.place_cursor(form, opts)
+  if not form then
+    return
+  end
+
+  local range = { form:range() }
+  local cursor_pos
+  if opts.placement == "left_edge" then
+    cursor_pos = { range[1] + 1, range[2] }
+  elseif opts.placement == "inner_start" then
+    cursor_pos = { range[1] + 1, range[2] + 1 }
+  elseif opts.placement == "inned_end" then
+    cursor_pos = { range[3] + 1, range[4] - 2 }
+  else
+    cursor_pos = { range[3] + 1, range[4] - 1 }
+  end
+  vim.api.nvim_win_set_cursor(0, cursor_pos)
+
+  if opts.mode == "insert" then
+    M.insert_mode()
+  end
+end
+
+return M

lua/nvim-paredit/api/motions.lua

@@ -5,8 +5,6 @@ local langs = require("nvim-paredit.lang")
 
 local M = {}
 
-local default_whitespace_chars = { " ", "," }
-
 -- When the cursor is placed on whitespace within a form then the node returned by
 -- the treesitter `get_node_at_cursor` fn is the outer form and not a child within
 -- the form.
@@ -24,13 +22,7 @@ local function get_next_node_from_cursor(lang, reversed)
   local cursor = vim.api.nvim_win_get_cursor(0)
   cursor = { cursor[1] - 1, cursor[2] }
 
-  local char_under_cursor = vim.api.nvim_buf_get_text(0, cursor[1], cursor[2], cursor[1], cursor[2] + 1, {})
-  local char_is_whitespace = common.included_in_table(
-    lang.whitespace_chars or default_whitespace_chars,
-    char_under_cursor[1]
-  ) or char_under_cursor[1] == ""
-
-  if not (lang.node_is_form(current_node) and char_is_whitespace) then
+  if not (lang.node_is_form(current_node) and common.is_whitespace_under_cursor(lang)) then
     return lang.get_node_root(current_node)
   end
 

lua/nvim-paredit/api/wrap.lua

@@ -0,0 +1,102 @@
+local traversal = require("nvim-paredit.utils.traversal")
+local common = require("nvim-paredit.utils.common")
+local ts = require("nvim-treesitter.ts_utils")
+local langs = require("nvim-paredit.lang")
+
+local M = {}
+
+local function reparse(buf)
+  local parser = vim.treesitter.get_parser(buf, vim.bo.filetype)
+  parser:parse()
+end
+
+function M.find_element_under_cursor(lang)
+  local node = ts.get_node_at_cursor()
+  return lang.get_node_root(node)
+end
+
+function M.find_form(element, lang)
+  return traversal.find_nearest_form(element, { lang = lang, use_source = false })
+end
+
+function M.find_parend_form(element, lang)
+  local nearest_form = M.find_form(element, lang)
+
+  if not nearest_form then
+    return element
+  end
+
+  local parent = nearest_form
+
+  if nearest_form:equal(element) then
+    parent = nearest_form:parent()
+  end
+
+  if parent and parent:type() ~= "source" then
+    return M.find_form(parent, lang)
+  end
+  return nearest_form
+end
+
+function M.wrap_element(buf, element, prefix, suffix)
+  prefix = prefix or ""
+  suffix = suffix or ""
+
+  local range = { element:range() }
+  vim.api.nvim_buf_set_text(buf, range[3], range[4], range[3], range[4], { suffix })
+  vim.api.nvim_buf_set_text(buf, range[1], range[2], range[1], range[2], { prefix })
+end
+
+function M.wrap_element_under_cursor(prefix, suffix)
+  local buf = vim.api.nvim_get_current_buf()
+  local lang = langs.get_language_api()
+  local current_element = M.find_element_under_cursor(lang)
+
+  if not current_element then
+    return
+  end
+  if lang.node_is_comment(current_element) then
+    return
+  end
+  if common.is_whitespace_under_cursor(lang) then
+    return
+  end
+
+  M.wrap_element(buf, current_element, prefix, suffix)
+
+  reparse(buf)
+
+  current_element = lang.get_node_root(ts.get_node_at_cursor())
+  return M.find_form(current_element, lang)
+end
+
+function M.wrap_enclosing_form_under_cursor(prefix, suffix)
+  local buf = vim.api.nvim_get_current_buf()
+  local lang = langs.get_language_api()
+  local current_element = M.find_element_under_cursor(lang)
+
+  if not current_element then
+    return
+  end
+
+  local use_direct_parent = common.is_whitespace_under_cursor(lang) or lang.node_is_comment(ts.get_node_at_cursor())
+
+  local form = M.find_form(current_element, lang)
+  if not use_direct_parent and form:type() ~= "source" then
+    form = M.find_parend_form(current_element, lang)
+  end
+
+  M.wrap_element(buf, form, prefix, suffix)
+
+  reparse(buf)
+
+  current_element = M.find_element_under_cursor(lang)
+  if use_direct_parent then
+    form = current_element
+  else
+    form = M.find_parend_form(current_element, lang)
+  end
+  return M.find_parend_form(form, lang)
+end
+
+return M

lua/nvim-paredit/init.lua

@@ -6,6 +6,8 @@ local lang = require("nvim-paredit.lang")
 
 local M = {
   api = require("nvim-paredit.api"),
+  wrap = require("nvim-paredit.api.wrap"),
+  cursor = require("nvim-paredit.api.cursor"),
 }
 
 local function setup_keybingings(filetype, buf)

lua/nvim-paredit/lang/init.lua

@@ -1,7 +1,11 @@
+local common = require("nvim-paredit.utils.common")
+
 local langs = {
   clojure = require("nvim-paredit.lang.clojure"),
 }
 
+local M = {}
+
 local function keys(tbl)
   local result = {}
   for k, _ in pairs(tbl) do
@@ -10,16 +14,16 @@ local function keys(tbl)
   return result
 end
 
-return {
-  get_language_api = function()
-    return langs[vim.bo.filetype]
-  end,
+function M.get_language_api()
+  return langs[vim.bo.filetype]
+end
 
-  add_language_extension = function(filetype, api)
-    langs[filetype] = api
-  end,
+function M.add_language_extension(filetype, api)
+  langs[filetype] = api
+end
 
-  filetypes = function()
-    return keys(langs)
-  end,
-}
+function M.filetypes()
+  return keys(langs)
+end
+
+return M

lua/nvim-paredit/utils/common.lua

@@ -65,5 +65,18 @@ function M.ensure_visual_mode()
   end
 end
 
+M.default_whitespace_chars = { " " }
+
+function M.is_whitespace_under_cursor(lang)
+  local cursor = vim.api.nvim_win_get_cursor(0)
+  cursor = { cursor[1] - 1, cursor[2] }
+
+  local char_under_cursor = vim.api.nvim_buf_get_text(0, cursor[1], cursor[2], cursor[1], cursor[2] + 1, {})
+  return M.included_in_table(
+    lang.whitespace_chars or M.default_whitespace_chars,
+    char_under_cursor[1]
+  ) or char_under_cursor[1] == ""
+end
+
 return M