Cycle previewers

lua/telescope/actions/init.lua

@@ -173,7 +173,9 @@ local do_close = function(prompt_bufnr, keepinsert)
   local original_win_id = picker.original_win_id
 
   if picker.previewer then
-    picker.previewer:teardown()
+    for _, v in ipairs(picker.all_previewers) do
+      v:teardown()
+    end
   end
 
   actions.close_pum(prompt_bufnr)
@@ -333,6 +335,16 @@ actions.open_qflist = function(_)
   vim.cmd [[copen]]
 end
 
+actions.cycle_previewers_next = function(prompt_bufnr)
+  local picker = actions.get_current_picker(prompt_bufnr)
+  picker:cycle_previewers(1)
+end
+
+actions.cycle_previewers_prev = function(prompt_bufnr)
+  local picker = actions.get_current_picker(prompt_bufnr)
+  picker:cycle_previewers(-1)
+end
+
 -- ==================================================
 -- Transforms modules and sets the corect metatables.
 -- ==================================================

lua/telescope/builtin/git.lua

@@ -45,6 +45,10 @@ git.commits = function(opts)
       entry_maker = opts.entry_maker or make_entry.gen_from_git_commits(opts),
     },
     previewer = previewers.git_commit_diff_to_parent.new(opts),
+    alt_previewers = {
+      previewers.git_commit_diff_to_head.new(opts),
+      previewers.git_commit_diff_as_was.new(opts),
+    },
     sorter = conf.file_sorter(opts),
     attach_mappings = function()
       actions.goto_file_selection_edit:replace(actions.git_checkout)
@@ -66,6 +70,10 @@ git.bcommits = function(opts)
       entry_maker = opts.entry_maker or make_entry.gen_from_git_commits(opts),
     },
     previewer = previewers.git_commit_diff_to_parent.new(opts),
+    alt_previewers = {
+      previewers.git_commit_diff_to_head.new(opts),
+      previewers.git_commit_diff_as_was.new(opts),
+    },
     sorter = conf.file_sorter(opts),
     attach_mappings = function()
       actions.goto_file_selection_edit:replace(actions.git_checkout_current_buffer)

lua/telescope/mappings.lua

@@ -24,6 +24,9 @@ mappings.default_mappings = config.values.default_mappings or {
       ["<C-u>"] = actions.preview_scrolling_up,
       ["<C-d>"] = actions.preview_scrolling_down,
 
+      ["<C-s>"] = actions.cycle_previewers_next,
+      ["<C-a>"] = actions.cycle_previewers_prev,
+
       -- TODO: When we implement multi-select, you can turn this back on :)
       -- ["<Tab>"] = actions.add_selection,
     },

lua/telescope/pickers.lua

@@ -80,7 +80,11 @@ function Picker:new(opts)
 
     finder = opts.finder,
     sorter = opts.sorter,
+
     previewer = opts.previewer,
+    all_previewers = opts.alt_previewers or {},
+    current_previewer_index = 1,
+
     default_selection_index = opts.default_selection_index,
 
     cwd = opts.cwd,
@@ -127,6 +131,7 @@ function Picker:new(opts)
     preview_cutoff = get_default(opts.preview_cutoff, config.values.preview_cutoff),
   }, self)
 
+  table.insert(obj.all_previewers, 1, obj.previewer)
 
   obj.scroller = p_scroller.create(
     get_default(opts.scroll_strategy, config.values.scroll_strategy),
@@ -748,6 +753,27 @@ function Picker:set_selection(row)
   end
 end
 
+function Picker:cycle_previewers(next)
+  local size = table.getn(self.all_previewers)
+  if size == 1 then return end
+
+  local status = state.get_status(self.prompt_bufnr)
+
+  self.current_previewer_index = self.current_previewer_index + next
+  if self.current_previewer_index > size then self.current_previewer_index = 1 end
+  if self.current_previewer_index < 1 then self.current_previewer_index = size end
+
+  self.previewer = self.all_previewers[self.current_previewer_index]
+
+  if status.preview_win and self.previewer then
+    self:_increment("previewed")
+
+    self.previewer:preview(
+      self._selection_entry,
+      status
+    )
+  end
+end
 
 function Picker:entry_adder(index, entry, _, insert)
   local row = self:get_row(index)

lua/telescope/previewers/init.lua

@@ -8,26 +8,29 @@ previewers.new = function(...)
   return Previewer:new(...)
 end
 
-previewers.new_termopen_previewer = term_previewer.new_termopen_previewer
-previewers.cat                    = term_previewer.cat
-previewers.vimgrep                = term_previewer.vimgrep
-previewers.qflist                 = term_previewer.qflist
+previewers.new_termopen_previewer    = term_previewer.new_termopen_previewer
+previewers.cat                       = term_previewer.cat
+previewers.vimgrep                   = term_previewer.vimgrep
+previewers.qflist                    = term_previewer.qflist
 
-previewers.new_buffer_previewer   = buffer_previewer.new_buffer_previewer
-previewers.buffer_previewer_maker = buffer_previewer.file_maker
-previewers.vim_buffer_cat         = buffer_previewer.cat
-previewers.vim_buffer_vimgrep     = buffer_previewer.vimgrep
-previewers.vim_buffer_qflist      = buffer_previewer.qflist
-previewers.git_branch_log         = buffer_previewer.git_branch_log
-previewers.git_commit_diff        = buffer_previewer.git_commit_diff
-previewers.git_file_diff          = buffer_previewer.git_file_diff
-previewers.ctags                  = buffer_previewer.ctags
-previewers.builtin                = buffer_previewer.builtin
-previewers.help                   = buffer_previewer.help
-previewers.man                    = buffer_previewer.man
-previewers.autocommands           = buffer_previewer.autocommands
-previewers.highlights             = buffer_previewer.highlights
-previewers.display_content        = buffer_previewer.display_content
+previewers.new_buffer_previewer      = buffer_previewer.new_buffer_previewer
+previewers.buffer_previewer_maker    = buffer_previewer.file_maker
+previewers.vim_buffer_cat            = buffer_previewer.cat
+previewers.vim_buffer_vimgrep        = buffer_previewer.vimgrep
+previewers.vim_buffer_qflist         = buffer_previewer.qflist
+previewers.git_branch_log            = buffer_previewer.git_branch_log
+previewers.git_commit_diff           = buffer_previewer.git_commit_diff
+previewers.git_commit_diff_to_parent = buffer_previewer.git_commit_diff_to_parent
+previewers.git_commit_diff_to_head   = buffer_previewer.git_commit_diff_to_head
+previewers.git_commit_diff_as_was    = buffer_previewer.git_commit_diff_as_was
+previewers.git_file_diff             = buffer_previewer.git_file_diff
+previewers.ctags                     = buffer_previewer.ctags
+previewers.builtin                   = buffer_previewer.builtin
+previewers.help                      = buffer_previewer.help
+previewers.man                       = buffer_previewer.man
+previewers.autocommands              = buffer_previewer.autocommands
+previewers.highlights                = buffer_previewer.highlights
+previewers.display_content           = buffer_previewer.display_content
 
 previewers.Previewer = Previewer