feat: changing buffers updates list positions

lua/harpoon2/config.lua

@@ -10,7 +10,10 @@ local M = {}
 ---@field select? (fun(list_item: HarpoonListItem, options: any?): nil)
 ---@field equals? (fun(list_line_a: HarpoonListItem, list_line_b: HarpoonListItem): boolean)
 ---@field add? fun(item: any?): HarpoonListItem
+---@field BufLeave? fun(evt: any, list: HarpoonList): nil
+---@field VimLeavePre? fun(evt: any, list: HarpoonList): nil
 
+---notehunthoeunthoeunthoeunthoeunthoeunth
 ---@class HarpoonSettings
 ---@field save_on_toggle boolean defaults to true
 ---@field jump_to_file_location boolean defaults to true
@@ -124,6 +127,20 @@ function M.get_default_config()
                     }
                 }
             end,
+
+            BufLeave = function(arg, list)
+                local bufnr = arg.buf;
+                local bufname = vim.api.nvim_buf_get_name(bufnr);
+                local item = list:get_by_display(bufname)
+
+                if item then
+                    local pos = vim.api.nvim_win_get_cursor(0)
+                    item.context.row = pos[1]
+                    item.context.col = pos[2]
+                end
+            end,
+
+            autocmds = {"BufLeave"},
         }
     }
 end

lua/harpoon2/init.lua

@@ -14,6 +14,7 @@ local DEFAULT_LIST = "__harpoon_files"
 ---@field config HarpoonConfig
 ---@field data HarpoonData
 ---@field lists {[string]: {[string]: HarpoonList}}
+---@field hooks_setup boolean
 local Harpoon = {}
 
 Harpoon.__index = Harpoon
@@ -26,6 +27,7 @@ function Harpoon:new()
         config = config,
         data = Data.Data:new(),
         lists = {},
+        hooks_setup = false,
     }, self)
 end
 
@@ -33,6 +35,32 @@ end
 ---@return Harpoon
 function Harpoon:setup(partial_config)
     self.config = Config.merge_config(partial_config, self.config)
+
+    if self.hooks_setup == false then
+        local augroup = vim.api.nvim_create_augroup
+        local HarpoonGroup = augroup('Harpoon', {})
+
+        vim.api.nvim_create_autocmd({"BufLeave", "VimLeavePre"}, {
+            group = HarpoonGroup,
+            pattern = '*',
+            callback = function(ev)
+                self:_for_each_list(function(list, config)
+
+                    local fn = config[ev.event]
+                    if fn ~= nil then
+                        fn(ev, list)
+                    end
+
+                    if ev.event == "VimLeavePre" then
+                        self:sync()
+                    end
+                end)
+            end,
+        })
+
+        self.hooks_setup = true
+    end
+
     return self
 end
 
@@ -64,22 +92,29 @@ function Harpoon:list(name)
     return list
 end
 
-function Harpoon:sync()
+---@param cb fun(list: HarpoonList, config: HarpoonPartialConfigItem, name: string)
+function Harpoon:_for_each_list(cb)
     local key = self.config.settings.key()
     local seen = self.data.seen[key]
     local lists = self.lists[key]
-    for list_name, _ in pairs(seen) do
-        local encoded = lists[list_name]:encode()
-        self.data:update(key, list_name, encoded)
+
+    if not seen then
+        return
+    end
+
+    for list_name, _ in pairs(seen) do
+        local list_config = Config.get_config(self.config, list_name)
+        cb(lists[list_name], list_config, list_name)
     end
-    self.data:sync()
 end
 
-function Harpoon:setup_hooks()
-    -- setup the autocommands
-    -- vim exits sync data
-    -- buf exit setup the cursor location
-    error("I haven't implemented this yet")
+function Harpoon:sync()
+    local key = self.config.settings.key()
+    self:_for_each_list(function(list, _, list_name)
+        local encoded = list:encode()
+        self.data:update(key, list_name, encoded)
+    end)
+    self.data:sync()
 end
 
 function Harpoon:info()

lua/harpoon2/list.lua

@@ -74,6 +74,16 @@ function HarpoonList:get(index)
     return self.items[index]
 end
 
+function HarpoonList:get_by_display(name)
+    local displayed = self:display()
+    local index = index_of(displayed, name)
+    if index == -1 then
+        return nil
+    end
+    return self.items[index]
+end
+
+
 --- much inefficiencies.  dun care
 ---@param displayed string[]
 function HarpoonList:resolve_displayed(displayed)

lua/harpoon2/test/harpoon_spec.lua

@@ -6,6 +6,7 @@ local eq = assert.are.same
 
 describe("harpoon", function()
 
+
     before_each(function()
         Data.set_data_path("/tmp/harpoon2.json")
         Data.__dangerously_clear_data()
@@ -25,6 +26,37 @@ describe("harpoon", function()
 
     end)
 
+    it("when we change buffers we update the row and column", function()
+        local file_name = "/tmp/harpoon-test"
+        local row = 1
+        local col = 0
+        local target_buf = utils.create_file(file_name, {
+            "foo",
+            "bar",
+            "baz",
+            "qux"
+        }, row, col)
+
+        local list = harpoon:list():append()
+        local other_buf = utils.create_file("other-file", {
+            "foo",
+            "bar",
+            "baz",
+            "qux"
+        }, row, col)
+
+        vim.api.nvim_set_current_buf(target_buf)
+        vim.api.nvim_win_set_cursor(0, {row + 1, col})
+        vim.api.nvim_set_current_buf(other_buf)
+
+        local expected = {
+            {value = file_name, context = {row = row + 1, col = col}},
+        }
+
+        eq(list.items, expected)
+
+    end)
+
     it("full harpoon add sync cycle", function()
         local file_name = "/tmp/harpoon-test"
         local row = 3