Add a changelist sign group

README.md

@@ -76,6 +76,8 @@ There is built-in support for various types of signs (referred to as "sign
 groups"), listed below. The functionality is similar to the sign column, but
 with the same positioning logic as the scrollbar.
 
+
+* `changelist`: change list items (previous, current, and next)
 * `conflicts`: git merge conflicts
 * `cursor`: cursor position
 * `diagnostics`: errors, warnings, info, and hints

autoload/scrollview.vim

@@ -76,6 +76,20 @@ let g:scrollview_signs_overflow = get(g:, 'scrollview_signs_overflow', 'left')
 let g:scrollview_signs_show_in_folds =
       \ get(g:, 'scrollview_signs_show_in_folds', v:false)
 
+" *** Change list signs ***
+let g:scrollview_changelist_previous_priority =
+      \ get(g:, 'scrollview_changelist_previous_priority', 15)
+let g:scrollview_changelist_previous_symbol =
+      \ get(g:, 'scrollview_changelist_previous_symbol', nr2char(0x1f894))
+let g:scrollview_changelist_current_priority =
+      \ get(g:, 'scrollview_changelist_current_priority', 10)
+let g:scrollview_changelist_current_symbol =
+      \ get(g:, 'scrollview_changelist_current_symbol', '@')
+let g:scrollview_changelist_next_priority =
+      \ get(g:, 'scrollview_changelist_next_priority', 5)
+let g:scrollview_changelist_next_symbol =
+      \ get(g:, 'scrollview_changelist_next_symbol', nr2char(0x1f896))
+
 " *** Conflict signs ***
 let g:scrollview_conflicts_bottom_priority =
       \ get(g:, 'scrollview_conflicts_bottom_priority', 80)

doc/scrollview.txt

@@ -150,6 +150,7 @@ Built-in Sign Groups ~
                                            *scrollview-signs-built-in*
 Group        Information
 -----        -----------
+`changelist`    change list items (previous, current, and next)
 `conflicts`     git merge conflicts
 `cursor`        cursor position
 `diagnostics`   errors, warnings, info, and hints via |vim.diagnostic|
@@ -315,6 +316,35 @@ scrollview_signs_show_in_folds             *scrollview_signs_show_in_folds*
                                            *scrollview-signs-built-in-config*
 Configuration Variables for Built-in Sign Groups ~
 
+scrollview_changelist_previous_priority    *scrollview_changelist_previous_priority*
+                       |Number| specifying the priority for the previous item
+                       changelist sign. Defaults to `15`. Considered only when
+                       the plugin is loaded.
+
+scrollview_changelist_previous_symbol      *scrollview_changelist_previous_symbol*
+                       |String| specifying the symbol for the previous item
+                       changelist sign. Defaults to a left-pointing arrow in a
+                       triangle.
+
+scrollview_changelist_current_priority     *scrollview_changelist_current_priority*
+                       |Number| specifying the priority for the current item
+                       changelist sign. Defaults to `10`. Considered only when
+                       the plugin is loaded.
+
+scrollview_changelist_current_symbol       *scrollview_changelist_current_symbol*
+                       |String| specifying the symbol for the current item
+                       changelist sign. Defaults to `'@'`.
+
+scrollview_changelist_next_priority        *scrollview_changelist_next_priority*
+                       |Number| specifying the priority for the next item
+                       changelist sign. Defaults to `5`. Considered only when
+                       the plugin is loaded.
+
+scrollview_changelist_next_symbol          *scrollview_changelist_next_symbol*
+                       |String| specifying the symbol for the next item
+                       changelist sign. Defaults to a right-pointing arrow in
+                       a triangle.
+
 scrollview_conflicts_bottom_priority       *scrollview_conflicts_bottom_priority*
                        |Number| specifying the priority for conflict bottom
                        signs. Defaults to `80`. Considered only when the

doc/tags

@@ -44,6 +44,12 @@ scrollview_always_show	scrollview.txt	/*scrollview_always_show*
 scrollview_auto_mouse	scrollview.txt	/*scrollview_auto_mouse*
 scrollview_base	scrollview.txt	/*scrollview_base*
 scrollview_byte_limit	scrollview.txt	/*scrollview_byte_limit*
+scrollview_changelist_current_priority	scrollview.txt	/*scrollview_changelist_current_priority*
+scrollview_changelist_current_symbol	scrollview.txt	/*scrollview_changelist_current_symbol*
+scrollview_changelist_next_priority	scrollview.txt	/*scrollview_changelist_next_priority*
+scrollview_changelist_next_symbol	scrollview.txt	/*scrollview_changelist_next_symbol*
+scrollview_changelist_previous_priority	scrollview.txt	/*scrollview_changelist_previous_priority*
+scrollview_changelist_previous_symbol	scrollview.txt	/*scrollview_changelist_previous_symbol*
 scrollview_character	scrollview.txt	/*scrollview_character*
 scrollview_column	scrollview.txt	/*scrollview_column*
 scrollview_conflicts_bottom_priority	scrollview.txt	/*scrollview_conflicts_bottom_priority*

lua/scrollview/signs/changelist.lua

@@ -0,0 +1,114 @@
+local api = vim.api
+local fn = vim.fn
+local scrollview = require('scrollview')
+
+local M = {}
+
+local PREVIOUS = 0
+local CURRENT = 1
+local NEXT = 2
+
+function M.init(enable)
+  if api.nvim_create_autocmd == nil then
+    return
+  end
+
+  local group = 'changelist'
+
+  local spec_data = {
+    [PREVIOUS] = {
+      vim.g.scrollview_changelist_previous_priority,
+      vim.g.scrollview_changelist_previous_symbol,
+      'ScrollViewChangeListPrevious'
+    },
+    [CURRENT] = {
+      vim.g.scrollview_changelist_current_priority,
+      vim.g.scrollview_changelist_current_symbol,
+      'ScrollViewChangeListCurrent'
+    },
+    [NEXT] = {
+      vim.g.scrollview_changelist_next_priority,
+      vim.g.scrollview_changelist_next_symbol,
+      'ScrollViewChangeListNext'
+    },
+  }
+  local names = {}  -- maps direction to registration name
+  for direction, item in pairs(spec_data) do
+    local priority, symbol, highlight = unpack(item)
+    local registration = scrollview.register_sign_spec({
+      group = group,
+      highlight = highlight,
+      priority = priority,
+      symbol = symbol,
+    })
+    names[direction] = registration.name
+  end
+  scrollview.set_sign_group_state(group, enable)
+
+  -- Refresh scrollbars after jumping through the change list.
+  scrollview.register_key_sequence_callback('g;', 'nv', scrollview.refresh)
+  scrollview.register_key_sequence_callback('g,', 'nv', scrollview.refresh)
+
+  api.nvim_create_autocmd('User', {
+    pattern = 'ScrollViewRefresh',
+    callback = function()
+      if not scrollview.is_sign_group_active(group) then return end
+      -- Track visited buffers, to prevent duplicate computation when multiple
+      -- windows are showing the same buffer.
+      local visited = {}
+      for _, winid in ipairs(scrollview.get_sign_eligible_windows()) do
+        local bufnr = api.nvim_win_get_buf(winid)
+        if not visited[bufnr] then
+          local bufvars = vim.b[bufnr]
+          for direction, name in pairs(names) do
+            -- luacheck: ignore 122 (setting read-only field b.?.? of global vim)
+            bufvars[name] = {}
+            local locations, position = unpack(fn.getchangelist(bufnr))
+            position = position + 1
+            if direction == PREVIOUS
+                and #locations > 0
+                and position - 1 > 0
+                and position - 1 <= #locations then
+              bufvars[name] = {locations[position - 1].lnum}
+            end
+            if direction == CURRENT
+                and #locations > 0
+                and position > 0
+                and position <= #locations then
+              bufvars[name] = {locations[position].lnum}
+            end
+            if direction == NEXT
+                and #locations > 0
+                and position + 1 > 0
+                and position + 1 <= #locations then
+              bufvars[name] = {locations[position + 1].lnum}
+            end
+          end
+          visited[bufnr] = true
+        end
+      end
+    end
+  })
+
+  api.nvim_create_autocmd('InsertLeave', {
+    callback = function()
+      if not scrollview.is_sign_group_active(group) then return end
+      scrollview.refresh()
+    end
+  })
+
+  api.nvim_create_autocmd('InsertEnter', {
+    callback = function()
+      if not scrollview.is_sign_group_active(group) then return end
+      api.nvim_create_autocmd('TextChangedI', {
+        callback = function()
+          if not scrollview.is_sign_group_active(group) then return end
+          scrollview.refresh()
+        end,
+        once = true
+      })
+    end
+  })
+end
+
+return M

plugin/scrollview.vim

@@ -23,6 +23,10 @@ endif
 " E.g., the following will use custom highlight colors.
 "   :highlight ScrollView ctermbg=159 guibg=LightCyan
 highlight default link ScrollView Visual
+highlight default link ScrollViewChangeListPrevious SpecialKey
+highlight default link ScrollViewChangeListCurrent SpecialKey
+highlight default link ScrollViewChangeListNext SpecialKey
+highlight default link ScrollViewConflictsMiddle DiffAdd
 highlight default link ScrollViewConflictsTop DiffAdd
 highlight default link ScrollViewConflictsMiddle DiffAdd
 highlight default link ScrollViewConflictsBottom DiffAdd