feat(index-tracking): keep track of the list._index while navigating

lua/harpoon/buffer.lua

@@ -29,18 +29,6 @@ end
 
 ---@param bufnr number
 function M.setup_autocmds_and_keymaps(bufnr)
-    local curr_file = vim.api.nvim_buf_get_name(0)
-    local cmd = string.format(
-        "autocmd Filetype harpoon "
-            .. "let path = '%s' | call clearmatches() | "
-            -- move the cursor to the line containing the current filename
-            .. "call search('\\V'.path.'\\$') | "
-            -- add a hl group to that line
-            .. "call matchadd('HarpoonCurrentFile', '\\V'.path.'\\$')",
-        curr_file:gsub("\\", "\\\\")
-    )
-    vim.cmd(cmd)
-
     if vim.api.nvim_buf_get_name(bufnr) == "" then
         vim.api.nvim_buf_set_name(bufnr, get_harpoon_menu_name())
     end

lua/harpoon/list.lua

@@ -1,4 +1,5 @@
 local Logger = require("harpoon.logger")
+local Path = require("plenary.path")
 local utils = require("harpoon.utils")
 local Extensions = require("harpoon.extensions")
 
@@ -77,16 +78,50 @@ end
 --- @field items HarpoonItem[]
 local HarpoonList = {}
 
+---@param list HarpoonList
+---@param options any
+local sync_index = function(list, options)
+    local bufnr = options.bufnr
+    local filename = options.filename
+    local index = options.index
+    if bufnr ~= nil and filename ~= nil then
+        local config = list.config
+        local relname = Path:new(filename):make_relative(config.get_root_dir())
+        if bufnr == vim.fn.bufnr(relname, false) then
+            local element = config.create_list_item(config, relname)
+            local index_found =
+                index_of(list.items, list._length, element, config)
+            if index_found > -1 then
+                list._index = index_found
+            end
+        elseif index ~= nil then
+            list._index = index
+        end
+    elseif index ~= nil then
+        list._index = index
+    end
+end
+
 HarpoonList.__index = HarpoonList
 function HarpoonList:new(config, name, items)
     items = items or {}
-    return setmetatable({
+    local list = setmetatable({
         items = items,
         config = config,
         name = name,
         _length = guess_length(items),
-        _index = 1,
+        _index = 0,
     }, self)
+    vim.api.nvim_create_autocmd({ "BufEnter" }, {
+        pattern = { "*" },
+        callback = function(args)
+            sync_index(list, {
+                bufnr = args.buf,
+                filename = args.file,
+            })
+        end,
+    })
+    return list
 end
 
 ---@return number
@@ -151,6 +186,8 @@ function HarpoonList:add(item)
             self._length = idx
         end
 
+        sync_index(self, { index = idx })
+
         Extensions.extensions:emit(
             Extensions.event_names.ADD,
             { list = self, item = item, idx = idx }
@@ -171,6 +208,8 @@ function HarpoonList:prepend(item)
             self._length = stop_idx
         end
 
+        sync_index(self, { index = 1 })
+
         Extensions.extensions:emit(
             Extensions.event_names.ADD,
             { list = self, item = item, idx = 1 }
@@ -191,6 +230,13 @@ function HarpoonList:remove(item)
             if i == self._length then
                 self._length = determine_length(self.items, self._length)
             end
+
+            local current_buffer = vim.api.nvim_get_current_buf()
+            sync_index(self, {
+                bufnr = current_buffer,
+                filename = vim.api.nvim_buf_get_name(current_buffer),
+            })
+
             Extensions.extensions:emit(
                 Extensions.event_names.REMOVE,
                 { list = self, item = item, idx = i }
@@ -212,6 +258,13 @@ function HarpoonList:remove_at(index)
         if index == self._length then
             self._length = determine_length(self.items, self._length)
         end
+
+        local current_buffer = vim.api.nvim_get_current_buf()
+        sync_index(self, {
+            bufnr = current_buffer,
+            filename = vim.api.nvim_buf_get_name(current_buffer),
+        })
+
         Extensions.extensions:emit(
             Extensions.event_names.REMOVE,
             { list = self, item = self.items[index], idx = index }
@@ -242,7 +295,10 @@ end
 --- much inefficiencies.  dun care
 ---@param displayed string[]
 ---@param length number
-function HarpoonList:resolve_displayed(displayed, length)
+---@param options any
+function HarpoonList:resolve_displayed(displayed, length, options)
+    options = options or {}
+
     local new_list = {}
 
     local list_displayed = self:display()
@@ -278,6 +334,12 @@ function HarpoonList:resolve_displayed(displayed, length)
         end
     end
 
+    local win_id = options.win_id
+    if win_id then
+        local pos = vim.api.nvim_win_get_cursor(win_id)
+        self._index = pos[1]
+    end
+
     self.items = new_list
     self._length = length
     if change > 0 then
@@ -288,6 +350,8 @@ end
 function HarpoonList:select(index, options)
     local item = self.items[index]
     if item or self.config.select_with_nil then
+        sync_index(self, { index = index })
+
         Extensions.extensions:emit(
             Extensions.event_names.SELECT,
             { list = self, item = item, idx = index }
@@ -344,8 +408,12 @@ end
 --- @return string[]
 function HarpoonList:encode()
     local out = {}
-    for _, v in ipairs(self.items) do
-        table.insert(out, self.config.encode(v))
+    local items = self.items
+    for i = 1, self._length do
+        local item = items[i]
+        if item then
+            out[i] = self.config.encode(items[i])
+        end
     end
 
     return out
@@ -358,8 +426,13 @@ end
 function HarpoonList.decode(list_config, name, items)
     local list_items = {}
 
-    for _, item in ipairs(items) do
-        table.insert(list_items, list_config.decode(item))
+    for i = 1, #items do
+        local item = items[i]
+        if item == vim.NIL then
+            list_items[i] = nil -- allow nil-values
+        else
+            list_items[i] = list_config.decode(item)
+        end
     end
 
     return HarpoonList:new(list_config, name, list_items)

lua/harpoon/test/harpoon_spec.lua

@@ -122,6 +122,31 @@ describe("harpoon", function()
         })
     end)
 
+    it("should ignore removed items", function()
+        local list = harpoon:list()
+
+        utils.create_file("/tmp/harpoon-test1", {}, 1, 0)
+        list:add()
+
+        utils.create_file("/tmp/harpoon-test2", {}, 1, 0)
+        list:add()
+
+        utils.create_file("/tmp/harpoon-test3", {}, 1, 0)
+        list:add()
+
+        list:remove_at(2) -- remove the second item
+
+        local count_items = 0
+        local encoded_items = list:encode()
+        local i, _ = next(encoded_items, nil)
+        while i do
+            count_items = count_items + 1
+            i, _ = next(encoded_items, i)
+        end
+
+        eq(2, count_items, "expecting two items in the list")
+    end)
+
     it("out of bounds test: row over", function()
         out_of_bounds_test({
             row = 5,

lua/harpoon/ui.lua

@@ -153,6 +153,12 @@ function HarpoonUI:toggle_quick_menu(list, opts)
     local contents = self.active_list:display()
     vim.api.nvim_buf_set_lines(self.bufnr, 0, -1, false, contents)
 
+    local index = list._index
+
+    if index > 0 then
+        vim.api.nvim_win_set_cursor(win_id, { index, 0 })
+    end
+
     Extensions.extensions:emit(Extensions.event_names.UI_CREATE, {
         win_id = win_id,
         bufnr = bufnr,
@@ -173,7 +179,7 @@ function HarpoonUI:select_menu_item(options)
     -- must first save any updates potentially made to the list before
     -- navigating
     local list, length = self:_get_processed_ui_contents()
-    self.active_list:resolve_displayed(list, length)
+    self.active_list:resolve_displayed(list, length, { win_id = self.win_id })
 
     Logger:log(
         "ui#select_menu_item selecting item",
@@ -193,7 +199,7 @@ function HarpoonUI:save()
     local list, length = self:_get_processed_ui_contents()
 
     Logger:log("ui#save", list)
-    self.active_list:resolve_displayed(list, length)
+    self.active_list:resolve_displayed(list, length, { win_id = self.win_id })
     if self.settings.sync_on_ui_close then
         require("harpoon"):sync()
     end