Allow views to be used as buffers and update API.

This allows for a superficial separation of buffer- and view-specific Scintilla
functionality. buffers and views can now be used interchangeably for the most
part, and the APIs are guidance, not hard requirements. User scripts do not
require any modification and will continue to function normally.

8 files changed, 31 insertions, 33 deletions

diff --git a/modules/textadept/command_entry.lua b/modules/textadept/command_entry.lua
index 29bea5b0..001dfa14 100644
--- a/modules/textadept/command_entry.lua
+++ b/modules/textadept/command_entry.lua
@@ -105,7 +105,7 @@ local function run_lua(code)
     end
     table.sort(items)
     result = string.format('{%s}', table.concat(items, ', '))
-    if buffer.edge_column > 0 and #result > buffer.edge_column then
+    if view.edge_column > 0 and #result > view.edge_column then
       local indent = string.rep(' ', buffer.tab_width)
       result = string.format(
         '{\n%s%s\n}', indent, table.concat(items, ',\n' .. indent))
diff --git a/modules/textadept/editing.lua b/modules/textadept/editing.lua
index 8206b93e..e7e5d9d0 100644
--- a/modules/textadept/editing.lua
+++ b/modules/textadept/editing.lua
@@ -53,7 +53,7 @@ M.XPM_IMAGES = {
 }
 events.connect(events.VIEW_NEW, function()
   for name, i in pairs(M.XPM_IMAGES) do
-    if type(name) == 'string' then buffer:register_image(i, M.XPM_IMAGES[i]) end
+    if type(name) == 'string' then view:register_image(i, M.XPM_IMAGES[i]) end
   end
 end)
 for _ = 1, #M.XPM_IMAGES do _SCINTILLA.next_image_type() end -- sync
@@ -160,11 +160,11 @@ events.connect(events.UPDATE_UI, function(updated)
   local pos = buffer.selection_n_caret[buffer.main_selection]
   if M.brace_matches[buffer.char_at[pos]] then
     local match = buffer:brace_match(pos, 0)
-    local f = match ~= -1 and buffer.brace_highlight or buffer.brace_bad_light
+    local f = match ~= -1 and view.brace_highlight or view.brace_bad_light
     f(buffer, pos, match)
     return
   end
-  buffer:brace_bad_light(-1)
+  view:brace_bad_light(-1)
 end)
 
 -- Moves over typeover characters when typed, taking multiple selections into
@@ -364,7 +364,7 @@ function M.goto_line(line)
     line = tonumber(value)
     if button ~= 1 or not line then return end
   end
-  buffer:ensure_visible_enforce_policy(line)
+  view:ensure_visible_enforce_policy(line)
   buffer:goto_line(line)
 end
 args.register(
diff --git a/modules/textadept/file_types.lua b/modules/textadept/file_types.lua
index 2889734c..34ae1dae 100644
--- a/modules/textadept/file_types.lua
+++ b/modules/textadept/file_types.lua
@@ -70,7 +70,7 @@ local function set_lexer(buffer, lang)
   buffer._lexer = lang
   if package.searchpath(lang, package.path) then _M[lang] = require(lang) end
   if buffer ~= ui.command_entry then events.emit(events.LEXER_LOADED, lang) end
-  local last_line = buffer.first_visible_line + buffer.lines_on_screen
+  local last_line = view.first_visible_line + view.lines_on_screen
   buffer:colourise(1, buffer:position_from_line(last_line + 1)) -- refresh
 end
 
diff --git a/modules/textadept/find.lua b/modules/textadept/find.lua
index d15558fb..e98b1403 100644
--- a/modules/textadept/find.lua
+++ b/modules/textadept/find.lua
@@ -122,7 +122,7 @@ local function find(text, next, flags, no_wrap, wrapped)
   if text == '' then return end
   if not flags then flags = get_flags() end
   if flags >= 1 << 31 then M.find_in_files() return end -- not performed here
-  local first_visible_line = buffer.first_visible_line -- for 'no results found'
+  local first_visible_line = view.first_visible_line -- for 'no results found'
 
   -- If text is selected, assume it is from the current search and move the
   -- caret appropriately for the next search.
@@ -132,8 +132,8 @@ local function find(text, next, flags, no_wrap, wrapped)
   buffer:search_anchor()
   local f = next and buffer.search_next or buffer.search_prev
   local pos = f(buffer, flags, text)
-  buffer:ensure_visible_enforce_policy(buffer:line_from_position(pos))
-  buffer:scroll_range(buffer.anchor, buffer.current_pos)
+  view:ensure_visible_enforce_policy(buffer:line_from_position(pos))
+  view:scroll_range(buffer.anchor, buffer.current_pos)
   find_text, found_text = text, buffer:get_sel_text() -- track for "replace all"
 
   -- If nothing was found, wrap the search.
@@ -144,7 +144,7 @@ local function find(text, next, flags, no_wrap, wrapped)
     pos = find(text, next, flags, true, true)
     if pos == -1 then
       ui.statusbar_text = _L['No results found']
-      buffer:line_scroll(0, first_visible_line - buffer.first_visible_line)
+      view:line_scroll(0, first_visible_line - view.first_visible_line)
       buffer:goto_pos(anchor)
     end
   elseif not wrapped then
diff --git a/modules/textadept/keys.lua b/modules/textadept/keys.lua
index a72899ca..212f85ea 100644
--- a/modules/textadept/keys.lua
+++ b/modules/textadept/keys.lua
@@ -486,8 +486,8 @@ if GUI then
   keys[not OSX and 'caI' or 'cI'] = m_view[_L['Toggle Show Indent Guides']][2]
   keys[not OSX and 'caV' or 'cV'] = m_view[_L['Toggle Virtual Space']][2]
 end
-keys[not OSX and GUI and 'c=' or 'm='] = buffer.zoom_in
-keys[not OSX and GUI and 'c-' or 'm-'] = buffer.zoom_out
+keys[not OSX and GUI and 'c=' or 'm='] = view.zoom_in
+keys[not OSX and GUI and 'c-' or 'm-'] = view.zoom_out
 keys[not OSX and GUI and 'c0' or 'm0'] = m_view[_L['Reset Zoom']][2]
 
 -- Help.
@@ -512,7 +512,7 @@ if OSX then
     buffer:line_end_extend()
     if not buffer.selection_empty then buffer:cut() else buffer:clear() end
   end
-  keys.cl = buffer.vertical_centre_caret
+  keys.cl = view.vertical_centre_caret
   -- GTK-OSX reports Fn-key as a single keycode which confuses Scintilla. Do
   -- not propagate it.
   keys.fn = function() return true end
diff --git a/modules/textadept/menu.lua b/modules/textadept/menu.lua
index a92c2498..c998ade6 100644
--- a/modules/textadept/menu.lua
+++ b/modules/textadept/menu.lua
@@ -292,17 +292,15 @@ local default_menubar = {
       {_L['UTF-16 Encoding'], function() set_encoding('UTF-16LE') end}
     },
     SEPARATOR,
-    {_L['Toggle View EOL'], function()
-      buffer.view_eol = not buffer.view_eol
-    end},
+    {_L['Toggle View EOL'], function() view.view_eol = not view.view_eol end},
     {_L['Toggle Wrap Mode'], function()
-      local first_visible_line = buffer.first_visible_line
-      local display_line = buffer:visible_from_doc_line(first_visible_line)
-      buffer.wrap_mode = buffer.wrap_mode == 0 and buffer.WRAP_WHITESPACE or 0
-      buffer:line_scroll(0, first_visible_line - display_line)
+      local first_visible_line = view.first_visible_line
+      local display_line = view:visible_from_doc_line(first_visible_line)
+      view.wrap_mode = view.wrap_mode == 0 and view.WRAP_WHITESPACE or 0
+      view:line_scroll(0, first_visible_line - display_line)
     end},
     {_L['Toggle View Whitespace'], function()
-      buffer.view_ws = buffer.view_ws == 0 and buffer.WS_VISIBLEALWAYS or 0
+      view.view_ws = view.view_ws == 0 and view.WS_VISIBLEALWAYS or 0
     end},
     SEPARATOR,
     {_L['Select Lexer...'], textadept.file_types.select_lexer},
@@ -318,28 +316,28 @@ local default_menubar = {
     {_L['Unsplit View'], function() view:unsplit() end},
     {_L['Unsplit All Views'], function() while view:unsplit() do end end},
     {_L['Grow View'], function()
-      if view.size then view.size = view.size + buffer:text_height(1) end
+      if view.size then view.size = view.size + view:text_height(1) end
     end},
     {_L['Shrink View'], function()
-      if view.size then view.size = view.size - buffer:text_height(1) end
+      if view.size then view.size = view.size - view:text_height(1) end
     end},
     SEPARATOR,
     {_L['Toggle Current Fold'], function()
-      buffer:toggle_fold(buffer:line_from_position(buffer.current_pos))
+      view:toggle_fold(buffer:line_from_position(buffer.current_pos))
     end},
     SEPARATOR,
     {_L['Toggle Show Indent Guides'], function()
-      local off = buffer.indentation_guides == 0
-      buffer.indentation_guides = off and buffer.IV_LOOKBOTH or 0
+      local off = view.indentation_guides == 0
+      view.indentation_guides = off and view.IV_LOOKBOTH or 0
     end},
     {_L['Toggle Virtual Space'], function()
       local off = buffer.virtual_space_options == 0
       buffer.virtual_space_options = off and buffer.VS_USERACCESSIBLE or 0
     end},
     SEPARATOR,
-    {_L['Zoom In'], buffer.zoom_in},
-    {_L['Zoom Out'], buffer.zoom_out},
-    {_L['Reset Zoom'], function() buffer.zoom = 0 end}
+    {_L['Zoom In'], view.zoom_in},
+    {_L['Zoom Out'], view.zoom_out},
+    {_L['Reset Zoom'], function() view.zoom = 0 end}
   },
   {
     title = _L['Help'],
diff --git a/modules/textadept/session.lua b/modules/textadept/session.lua
index b446ca54..43bb9e08 100644
--- a/modules/textadept/session.lua
+++ b/modules/textadept/session.lua
@@ -62,7 +62,7 @@ function M.load(filename)
     if lfs.attributes(buf.filename) then
       io.open_file(buf.filename)
       buffer:set_sel(buf.anchor, buf.current_pos)
-      buffer:line_scroll(0, buf.top_line - buffer.first_visible_line)
+      view:line_scroll(0, buf.top_line - view.first_visible_line)
       for _, line in ipairs(buf.bookmarks) do
         buffer:marker_add(line, textadept.bookmarks.MARK_BOOKMARK)
       end
@@ -165,7 +165,7 @@ function M.save(filename)
       filename = buffer.filename or buffer._type,
       anchor = current and buffer.anchor or buffer._anchor,
       current_pos = current and buffer.current_pos or buffer._current_pos,
-      top_line = current and buffer.first_visible_line or buffer._top_line,
+      top_line = current and view.first_visible_line or buffer._top_line,
     }
     local bookmarks = {}
     local BOOKMARK_BIT = 1 << textadept.bookmarks.MARK_BOOKMARK - 1
diff --git a/modules/textadept/snippets.lua b/modules/textadept/snippets.lua
index 707ab7ca..73f46bde 100644
--- a/modules/textadept/snippets.lua
+++ b/modules/textadept/snippets.lua
@@ -653,8 +653,8 @@ events.connect(events.UPDATE_UI, function(updated)
 end)
 
 events.connect(events.VIEW_NEW, function()
-  buffer.indic_style[INDIC_SNIPPET] = buffer.INDIC_HIDDEN
-  buffer.indic_style[INDIC_CURRENTPLACEHOLDER] = buffer.INDIC_HIDDEN
+  view.indic_style[INDIC_SNIPPET] = view.INDIC_HIDDEN
+  view.indic_style[INDIC_CURRENTPLACEHOLDER] = view.INDIC_HIDDEN
 end)
 
 -- Returns for the word behind the caret a list of snippet trigger word