3 files changed, 62 insertions, 4 deletions
diff --git a/modules/textadept/editing.lua b/modules/textadept/editing.lua
index 4f6dc61e..75844a44 100644
--- a/modules/textadept/editing.lua
+++ b/modules/textadept/editing.lua
@@ -11,6 +11,9 @@ local M = {}
 -- @field strip_trailing_spaces (bool)
 --   Strip trailing whitespace before saving files.
 --   The default value is `false`.
+-- @field paste_reindents (bool)
+--   Reindent pasted text according to the buffer's indentation settings.
+--   The default value is `true`.
 -- @field autocomplete_all_words (bool)
 --   Autocomplete the current word using words from all open buffers.
 --   If `true`, performance may be slow when many buffers are open.
@@ -23,6 +26,7 @@ module('textadept.editing')]]
 
 M.auto_indent = true
 M.strip_trailing_spaces = false
+M.paste_reindents = true
 M.autocomplete_all_words = false
 M.INDIC_BRACEMATCH = _SCINTILLA.next_indic_number()
 M.INDIC_HIGHLIGHT = _SCINTILLA.next_indic_number()
@@ -226,6 +230,60 @@ events.connect(events.FILE_BEFORE_SAVE, function()
 end)
 
 ---
+-- Pastes the text from the clipboard, taking into account the buffer's
+-- indentation settings and the indentation of the current and preceding lines.
+-- @name paste
+function M.paste()
+  local line = buffer:line_from_position(buffer.selection_start)
+  if not M.paste_reindents or
+     buffer.selection_start > buffer.line_indent_position[line] then
+    buffer:paste()
+    return
+  end
+  -- Strip leading indentation from clipboard text.
+  local text = ui.clipboard_text
+  local lead = text:match('^%s*')
+  if lead ~= '' then text = text:sub(#lead + 1):gsub('\n'..lead, '\n') end
+  -- Change indentation to match buffer indentation settings.
+  local tab_width = math.huge
+  text = text:gsub('\n([ \t]+)', function(indentation)
+    if indentation:find('^\t') then
+      if buffer.use_tabs then return '\n'..indentation end
+      return '\n'..indentation:gsub('\t', string.rep(' ', buffer.tab_width))
+    else
+      tab_width = math.min(tab_width, #indentation)
+      local indent = math.floor(#indentation / tab_width)
+      local spaces = string.rep(' ', math.fmod(#indentation, tab_width))
+      if buffer.use_tabs then return '\n'..string.rep('\t', indent)..spaces end
+      return '\n'..string.rep(' ', buffer.tab_width):rep(indent)..spaces
+    end
+  end)
+  -- Re-indent according to whichever of the current and preceding lines has the
+  -- higher indentation amount.
+  local i = line - 1
+  while i >= 0 and buffer:get_line(i):find('^[\r\n]+$') do i = i - 1 end
+  if i < 0 or buffer.line_indentation[i] < buffer.line_indentation[line] then
+    i = line
+  end
+  local s, e = buffer:position_from_line(i), buffer.line_indent_position[i]
+  text = text:gsub('\n', '\n'..buffer:text_range(s, e))
+  -- Paste the text and adjust first and last line indentation accordingly.
+  local start_indent = buffer.line_indentation[i]
+  local end_line = buffer:line_from_position(buffer.selection_end)
+  local end_indent = buffer.line_indentation[end_line]
+  local end_column = buffer.column[buffer.selection_end]
+  buffer:begin_undo_action()
+  buffer:replace_sel(text)
+  buffer.line_indentation[line] = start_indent
+  if text:find('\n') then
+    local line = buffer:line_from_position(buffer.current_pos)
+    buffer.line_indentation[line] = end_indent
+    buffer:goto_pos(buffer:find_column(line, end_column))
+  end
+  buffer:end_undo_action()
+end
+
+---
 -- Goes to the current character's matching brace, selecting the text in between
 -- if *select* is `true`.
 -- @param select Optional flag indicating whether or not to select the text
diff --git a/modules/textadept/keys.lua b/modules/textadept/keys.lua
index e5f0d8f5..40ff9ef9 100644
--- a/modules/textadept/keys.lua
+++ b/modules/textadept/keys.lua
@@ -297,7 +297,7 @@ if not OSX then keys.cy = buffer.redo end
 keys[not OSX and GUI and 'cZ' or 'mZ'] = buffer.redo
 keys[not OSX and 'cx' or 'mx'] = buffer.cut
 keys[not OSX and 'cc' or 'mc'] = buffer.copy
-keys[not OSX and 'cv' or 'mv'] = buffer.paste
+keys[not OSX and 'cv' or 'mv'] = textadept.editing.paste
 if GUI then keys[not OSX and 'cd' or 'md'] = buffer.line_duplicate end
 keys.del = buffer.clear
 keys[not OSX and (GUI and 'adel' or 'mdel')
diff --git a/modules/textadept/menu.lua b/modules/textadept/menu.lua
index 82104336..ad23552f 100644
--- a/modules/textadept/menu.lua
+++ b/modules/textadept/menu.lua
@@ -18,8 +18,8 @@ local SEPARATOR = {''}
 -- The following buffer functions need to be constantized in order for menu
 -- items to identify the key associated with the functions.
 local menu_buffer_functions = {
-  'undo', 'redo', 'cut', 'copy', 'paste', 'line_duplicate', 'clear',
-  'select_all', 'upper_case', 'lower_case', 'move_selected_lines_up',
+  'undo', 'redo', 'cut', 'copy', 'line_duplicate', 'clear', 'select_all',
+  'upper_case', 'lower_case', 'move_selected_lines_up',
   'move_selected_lines_down', 'zoom_in', 'zoom_out', 'colourise'
 }
 for i = 1, #menu_buffer_functions do
@@ -81,7 +81,7 @@ local default_menubar = {
     SEPARATOR,
     {_L['Cu_t'], buffer.cut},
     {_L['_Copy'], buffer.copy},
-    {_L['_Paste'], buffer.paste},
+    {_L['_Paste'], textadept.editing.paste},
     {_L['Duplicate _Line'], buffer.line_duplicate},
     {_L['_Delete'], buffer.clear},
     {_L['D_elete Word'], function()