Refactor indentexpr() to fix noindent indentation for lists.

lua/orgmode/org/indent.lua

@@ -30,11 +30,24 @@ local get_matches = ts_utils.memoize_by_buf_tick(function(bufnr)
         matches[range.start.line + 1] = opts
       end
 
-      if type == 'list' then
-        local first_list_item = node:named_child(0)
-        local first_list_item_linenr = first_list_item:start()
-        local first_item_indent = vim.fn.indent(first_list_item_linenr + 1)
-        opts.indent = first_item_indent
+      if type == 'listitem' then
+        local content = node:named_child(1)
+        if content then
+          local content_linenr, content_indent = content:start()
+          if content_linenr == range.start.line then
+            opts.overhang = content_indent - opts.indent
+          end
+        end
+        if not opts.overhang then
+          local bullet = node:named_child(0)
+          opts.overhang = vim.treesitter.get_node_text(bullet, bufnr):len() + 1
+        end
+
+        local parent = node:parent()
+        while parent and parent:type() ~= 'section' and parent:type() ~= 'listitem' do
+          parent = parent:parent()
+        end
+        opts.nesting_parent_linenr = parent and (parent:start() + 1)
 
         for i = range.start.line, range['end'].line - 1 do
           matches[i + 1] = opts
@@ -46,9 +59,6 @@ local get_matches = ts_utils.memoize_by_buf_tick(function(bufnr)
         local parent = node:parent()
         while parent and parent:type() ~= 'section' do
           parent = parent:parent()
-          if not parent then
-            break
-          end
         end
         if parent then
           local headline = parent:named_child('headline')
@@ -106,20 +116,16 @@ local function foldexpr()
   return '='
 end
 
-local function get_is_list_item(line)
-  local line_numbered_list_item = line:match('^%s*(%d+[%)%.]%s+)')
-  local line_unordered_list_item = line:match('^%s*([%+%-]%s+)')
-  return line_numbered_list_item or line_unordered_list_item
-end
-
-local function indentexpr()
+local function indentexpr(linenr, mode)
+  linenr = linenr or vim.v.lnum
+  mode = mode or vim.fn.mode()
   local noindent_mode = config.org_indent_mode == 'noindent'
   query = query or vim.treesitter.query.get('org', 'org_indent')
 
-  local prev_linenr = vim.fn.prevnonblank(vim.v.lnum - 1)
+  local prev_linenr = vim.fn.prevnonblank(linenr - 1)
 
   local matches = get_matches(0)
-  local match = matches[vim.v.lnum]
+  local match = matches[linenr]
   local prev_line_match = matches[prev_linenr]
 
   if not match and not prev_line_match then
@@ -140,26 +146,49 @@ local function indentexpr()
     return 0
   end
 
-  if match.type == 'list' and prev_line_match.type == 'list' then
-    local prev_line_list_item = get_is_list_item(vim.fn.getline(prev_linenr))
-    local cur_line_list_item = get_is_list_item(vim.fn.getline(vim.v.lnum))
-
-    if cur_line_list_item then
-      local diff = match.indent - vim.fn.indent(match.line_nr)
-      local indent = vim.fn.indent(vim.v.lnum)
-      return indent - diff
+  if match.type == 'listitem' then
+    -- We first figure out the indent of the first line of a listitem. Then we
+    -- check if we're on the first line or a "hanging" line. In the latter
+    -- case, we add the overhang.
+    local first_line_indent
+    local parent_linenr = match.nesting_parent_linenr
+    if parent_linenr then
+      local parent_match = matches[parent_linenr]
+      if parent_match.type == 'listitem' then
+        -- Nested listitem. Because two listitems cannot start on the same line,
+        -- we simply fetch the parent's indentation and add its overhang.
+        -- Don't use parent_match.indent, it might be stale if the parent
+        -- already got reindented.
+        first_line_indent = vim.fn.indent(parent_linenr) + parent_match.overhang
+      elseif parent_match.type == 'headline' and not noindent_mode then
+        -- Un-nested list inside a section, indent according to section.
+        first_line_indent = parent_match.indent
+      else
+        -- Noindent mode.
+        first_line_indent = 0
+      end
+    else
+      -- Top-level list before the first headline.
+      first_line_indent = 0
     end
-
-    if prev_line_list_item then
-      return vim.fn.indent(prev_linenr) + prev_line_list_item:len()
+    -- Add overhang if this is a hanging line.
+    if linenr ~= match.line_nr then
+      return first_line_indent + match.overhang
     end
+    return first_line_indent
   end
 
-  if prev_line_match.type == 'list' and match.type ~= 'list' then
-    local prev_line_list_item = get_is_list_item(vim.fn.getline(prev_linenr))
-    if prev_line_list_item then
-      return vim.fn.indent(prev_linenr) + prev_line_list_item:len()
+  -- In insert mode, we also count the non-listitem line *after* a listitem as
+  -- part of the listitem. Keep in mind that double empty lines end a list as
+  -- per Orgmode syntax.
+  if mode:match('^[iR]') and prev_line_match.type == 'listitem' and linenr - prev_linenr < 3 then
+    -- After the first line of a listitem, we have to add the overhang to the
+    -- listitem's own base indent. After all further lines, we can simply copy
+    -- the indentation.
+    if prev_linenr == prev_line_match.line_nr then
+      return vim.fn.indent(prev_linenr) + prev_line_match.overhang
     end
+    return vim.fn.indent(prev_linenr)
   end
 
   if noindent_mode then

queries/org/org_indent.scm

@@ -1,5 +1,5 @@
 (headline) @OrgIndentHeadline
-(body (list) @OrgList)
+(listitem) @OrgListItem
 (body (paragraph) @OrgParagraph)
 (body (drawer) @OrgDrawer)
 (section (property_drawer) @OrgPropertyDrawer)

scripts/gendoc.lua

@@ -8,4 +8,4 @@ local files = {
 local destination = 'doc/orgmode_api.txt'
 
 vim.fn.system(('lemmy-help %s > %s'):format(table.concat(files, ' '), destination))
-vim.cmd[[qa!]]
+vim.cmd([[qa!]])

tests/minimal_init.lua

@@ -85,6 +85,7 @@ M.setup({
 vim.opt.runtimepath:prepend(vim.fn.fnamemodify(base_root_path, ':h'))
 vim.opt.termguicolors = true
 vim.opt.swapfile = false
+vim.opt.expandtab = true -- Accommodates some deep nesting in indent_spec.lua
 vim.cmd.language('en_US.utf-8')
 vim.env.TZ = 'Europe/London'
 vim.g.mapleader = ','

tests/plenary/org/indent_spec.lua

@@ -0,0 +1,215 @@
+local config = require('orgmode.config')
+local Indent = require('orgmode.org.indent')
+local helpers = require('tests.plenary.ui.helpers')
+
+-- Helper assert function.
+local function expect_whole_buffer(expected)
+  assert.are.same(expected, vim.api.nvim_buf_get_lines(0, 0, -1, false))
+end
+
+-- We want to run all tests under both values for `org_indent_mode`: "indent"
+-- and "noindent". So it is easier to put all tests into test functions and
+-- check the indent mode, then run them under two different `describe()`.
+
+local function test_full_reindent()
+  local unformatted_file = {
+    '* TODO First task',
+    'SCHEDULED: <1970-01-01 Thu>',
+    '',
+    '1. Ordered list',
+    '   a) nested list',
+    '          over-indented',
+    '          over-indented',
+    '   b) nested list',
+    '    under-indented',
+    '2. Ordered list',
+    'Not part of the list',
+    '',
+    '** Second task',
+    '         DEADLINE: <1970-01-01 Thu>',
+    '',
+    '- Unordered list',
+    '  + nested list',
+    '        over-indented',
+    '        over-indented',
+    '  + nested list',
+    '   under-indented',
+    '- unordered list',
+    ' + nested list',
+    '  * triple nested list',
+    '    continuation',
+    ' part of the first-level list',
+    'Not part of the list',
+  }
+  helpers.load_file_content(unformatted_file)
+  vim.cmd([[silent norm 0gg=G]])
+  local expected
+  if config.org_indent_mode == 'indent' then
+    expected = {
+      '* TODO First task',
+      '  SCHEDULED: <1970-01-01 Thu>',
+      '',
+      '  1. Ordered list',
+      '     a) nested list',
+      '        over-indented',
+      '        over-indented',
+      '     b) nested list',
+      '        under-indented',
+      '  2. Ordered list',
+      '  Not part of the list',
+      '',
+      '** Second task',
+      '   DEADLINE: <1970-01-01 Thu>',
+      '',
+      '   - Unordered list',
+      '     + nested list',
+      '       over-indented',
+      '       over-indented',
+      '     + nested list',
+      '       under-indented',
+      '   - unordered list',
+      '     + nested list',
+      '       * triple nested list',
+      '         continuation',
+      '     part of the first-level list',
+      '   Not part of the list',
+    }
+  elseif config.org_indent_mode == 'noindent' then
+    expected = {
+      '* TODO First task',
+      'SCHEDULED: <1970-01-01 Thu>',
+      '',
+      '1. Ordered list',
+      '   a) nested list',
+      '      over-indented',
+      '      over-indented',
+      '   b) nested list',
+      '      under-indented',
+      '2. Ordered list',
+      'Not part of the list',
+      '',
+      '** Second task',
+      'DEADLINE: <1970-01-01 Thu>',
+      '',
+      '- Unordered list',
+      '  + nested list',
+      '    over-indented',
+      '    over-indented',
+      '  + nested list',
+      '    under-indented',
+      '- unordered list',
+      '  + nested list',
+      '    * triple nested list',
+      '      continuation',
+      '  part of the first-level list',
+      'Not part of the list',
+    }
+  end
+  expect_whole_buffer(expected)
+end
+
+local function test_newly_written_list()
+  helpers.load_file_content({})
+  local user_input = vim.api.nvim_replace_termcodes('i- new item<CR>second line<CR>third line<Esc>', true, true, true)
+  vim.api.nvim_feedkeys(user_input, 'ntix', false)
+  local expected
+  if config.org_indent_mode == 'indent' then
+    expected = {
+      '- new item',
+      '  second line',
+      '  third line',
+    }
+  elseif config.org_indent_mode == 'noindent' then
+    expected = {
+      '- new item',
+      '  second line',
+      '  third line',
+    }
+  end
+  expect_whole_buffer(expected)
+end
+
+local function test_insertion_to_an_existing_list()
+  helpers.load_file_content({ '- first item', '- third item' })
+  vim.cmd([[normal! o]])
+  local user_input = vim.api.nvim_replace_termcodes('i- new item<CR>second line<CR>third line<Esc>', true, true, true)
+  vim.api.nvim_feedkeys(user_input, 'ntix', false)
+  local expected
+  if config.org_indent_mode == 'indent' then
+    expected = {
+      '- first item',
+      '- new item',
+      '  second line',
+      '  third line',
+      '- third item',
+    }
+  elseif config.org_indent_mode == 'noindent' then
+    expected = {
+      '- first item',
+      '- new item',
+      '  second line',
+      '  third line',
+      '- third item',
+    }
+  end
+  expect_whole_buffer(expected)
+end
+
+local function test_add_line_breaks_to_existing_file()
+  helpers.load_file_content({ '- first item', '- second item' })
+  local user_input = vim.api.nvim_replace_termcodes('wwi<CR><Esc><Down><Right>i<CR><Esc>', true, true, true)
+  vim.api.nvim_feedkeys(user_input, 'ntix', false)
+  local expected = {
+    '- first ',
+    '  item',
+    '- ',
+    '  second item',
+  }
+  expect_whole_buffer(expected)
+end
+
+-- The actual tests are here.
+
+describe('with "indent",', function()
+  before_each(function()
+    config:extend({ org_indent_mode = 'indent' })
+  end)
+
+  it('"0gg=G" reindents the whole file', function()
+    test_full_reindent()
+  end)
+
+  it('a newly written list is well indented', function()
+    test_newly_written_list()
+  end)
+
+  it('insertion to an existing list is well indented', function()
+    test_insertion_to_an_existing_list()
+  end)
+
+  it('adding line breaks to list items maintains indent', function()
+    test_add_line_breaks_to_existing_file()
+  end)
+end)
+
+describe('with "noindent",', function()
+  before_each(function()
+    config:extend({ org_indent_mode = 'noindent' })
+  end)
+
+  it('"0gg=G" reindents the whole file', function()
+    test_full_reindent()
+  end)
+
+  it('a newly written list is well indented', function()
+    test_newly_written_list()
+  end)
+
+  it('insertion into an existing list is well indented', function()
+    test_insertion_to_an_existing_list()
+  end)
+
+  it('adding line breaks to list items maintains indent', function()
+    test_add_line_breaks_to_existing_file()
+  end)
+end)