list: save and restore cursor positions

Harpoon was not remembering the cursor position after quitting nvim.
Ensure that the cursor information is always saved and applied so that
we get back to exactly where we last were in the harpooned file.

Closes: #441

Author: davvid

lua/harpoon/config.lua

@@ -1,5 +1,6 @@
 local Extensions = require("harpoon.extensions")
 local Logger = require("harpoon.logger")
+local List = require("harpoon.list")
 local Utils = require("harpoon.utils")
 
 local function to_exact_name(value)
@@ -102,13 +103,11 @@ function M.get_default_config()
                     return
                 end
 
+                list:sync_cursor()
                 options = options or {}
 
                 local bufnr = vim.fn.bufnr(to_exact_name(list_item.value))
-                local set_position = false
                 if bufnr == -1 then -- must create a buffer!
-                    set_position = true
-                    -- bufnr = vim.fn.bufnr(list_item.value, true)
                     bufnr = vim.fn.bufadd(list_item.value)
                 end
                 if not vim.api.nvim_buf_is_loaded(bufnr) then
@@ -128,39 +127,42 @@ function M.get_default_config()
 
                 vim.api.nvim_set_current_buf(bufnr)
 
-                if set_position then
-                    local lines = vim.api.nvim_buf_line_count(bufnr)
+                local lines = vim.api.nvim_buf_line_count(bufnr)
 
-                    local edited = false
-                    if list_item.context.row > lines then
-                        list_item.context.row = lines
-                        edited = true
-                    end
+                local edited = false
+                if list_item.context.row > lines then
+                    list_item.context.row = lines
+                    edited = true
+                end
 
-                    local row = list_item.context.row
-                    local row_text =
-                        vim.api.nvim_buf_get_lines(0, row - 1, row, false)
-                    local col = #row_text[1]
+                local row = list_item.context.row
+                local row_text =
+                    vim.api.nvim_buf_get_lines(0, row - 1, row, false)
+                local col = #row_text[1]
 
-                    if list_item.context.col > col then
-                        list_item.context.col = col
-                        edited = true
-                    end
+                if list_item.context.col > col then
+                    list_item.context.col = col
+                    edited = true
+                end
 
-                    vim.api.nvim_win_set_cursor(0, {
-                        list_item.context.row or 1,
-                        list_item.context.col or 0,
-                    })
+                vim.api.nvim_win_set_cursor(0, {
+                    list_item.context.row or 1,
+                    list_item.context.col or 0,
+                })
 
-                    if edited then
-                        Extensions.extensions:emit(
-                            Extensions.event_names.POSITION_UPDATED,
-                            {
-                                list_item = list_item,
-                            }
-                        )
-                    end
+                if edited then
+                    Extensions.extensions:emit(
+                        Extensions.event_names.POSITION_UPDATED,
+                        {
+                            list_item = list_item,
+                        }
+                    )
                 end
+                -- The stored cursor position could be outside of the file bounds.
+                pcall(vim.api.nvim_win_set_cursor, 0, {
+                    list_item.context.row or 1,
+                    list_item.context.col or 0,
+                })
 
                 Extensions.extensions:emit(Extensions.event_names.NAVIGATE, {
                     buffer = bufnr,
@@ -224,7 +226,7 @@ function M.get_default_config()
                 local item = list:get_by_value(bufname)
 
                 if item then
-                    local pos = vim.api.nvim_win_get_cursor(0)
+                    local pos = List._sync_cursor(item)
 
                     Logger:log(
                         "config_default#BufLeave updating position",

lua/harpoon/init.lua

@@ -104,6 +104,7 @@ function Harpoon:sync()
             return
         end
 
+        list:sync_cursor()
         local encoded = list:encode()
         self.data:update(key, list_name, encoded)
     end)

lua/harpoon/list.lua

@@ -1,5 +1,6 @@
 local Logger = require("harpoon.logger")
 local Extensions = require("harpoon.extensions")
+local Utils = require("harpoon.utils")
 
 local function guess_length(arr)
     local last_known = #arr
@@ -284,6 +285,17 @@ function HarpoonList:resolve_displayed(displayed, length)
     end
 end
 
+function HarpoonList:sync_cursor()
+    local current_display = Utils.normalize_path(
+        vim.api.nvim_buf_get_name(vim.api.nvim_get_current_buf()),
+        self.config.get_root_dir()
+    )
+    local item = self:get_by_value(current_display)
+    if item then
+        HarpoonList._sync_cursor(item)
+    end
+end
+
 function HarpoonList:select(index, options)
     local item = self.items[index]
     if item or self.config.select_with_nil then
@@ -364,4 +376,13 @@ function HarpoonList.decode(list_config, name, items)
     return HarpoonList:new(list_config, name, list_items)
 end
 
+--- @return integer[]
+--- @param item HarpoonItem
+function HarpoonList._sync_cursor(item)
+    local pos = vim.api.nvim_win_get_cursor(0)
+    item.context.row = pos[1]
+    item.context.col = pos[2]
+    return pos
+end
+
 return HarpoonList