feat: allow follow_tab to be a function

Using window options should open some doors. Most notably, the
simplification of some stuff

Author: igorlfs

docs/src/routes/configuration/+page.md

@@ -145,7 +145,9 @@ return {
     switchbuf = "usetab,uselast",
     -- Auto open when a session is started and auto close when all sessions finish
     auto_toggle = false,
-    -- Reopen dapview when switching tabs
+    -- Reopen dapview when switching to a different tab
+    -- Can also be a function to dynamically choose when to follow, by returning a boolean
+    -- If a function, receives the name of the adapter for the current session as an argument
     follow_tab = false,
 }
 ```

docs/src/routes/faq/+page.md

@@ -9,6 +9,7 @@ title: FAQ
 ```lua
 -- Your nvim-dap-view config
 return {
+    -- Can also be a function to dynamically choose when to follow, by returning a boolean
     follow_tab = true,
 }
 ```

lua/dap-view/actions.lua

@@ -79,7 +79,7 @@ M.open = function(hide_terminal)
     local windows_config = setup.config.windows
     local term_config = windows_config.terminal
 
-    local term_position = require("dap-view.util").inverted_directions[term_config.position]
+    local term_position = util.inverted_directions[term_config.position]
 
     local anchor_win = windows_config.anchor and windows_config.anchor()
     local is_anchor_win_valid = util.is_win_valid(anchor_win)
@@ -97,6 +97,8 @@ M.open = function(hide_terminal)
 
     state.winnr = winnr
 
+    vim.w[state.winnr].dapview_win = true
+
     require("dap-view.views.options").set_options()
     require("dap-view.views.keymaps").set_keymaps()
 

lua/dap-view/autocmds.lua

@@ -1,4 +1,7 @@
+local dap = require("dap")
+
 local util = require("dap-view.util")
+local window = require("dap-view.util.window")
 local state = require("dap-view.state")
 local setup = require("dap-view.setup")
 local globals = require("dap-view.globals")
@@ -18,7 +21,40 @@ api.nvim_create_autocmd({ "WinClosed", "WinNew" }, {
 
 api.nvim_create_autocmd("TabEnter", {
     callback = function()
-        if util.is_win_valid(state.winnr) and setup.config.follow_tab then
+        local session = dap.session()
+        local adapter = session and session.config.type
+
+        local follow_tab = setup.config.follow_tab
+        local follow_tab_ = (type(follow_tab) == "function" and follow_tab(adapter))
+            or (type(follow_tab) == "boolean" and follow_tab)
+
+        local open_winnr = window.fetch_window()
+
+        -- When follow_tab is a function, we have to "restore" what otherwise would be a leftover window
+        --
+        -- Consider the following scenario:
+        -- - Tab 1 is active and has a dap-view window
+        -- - User switches to tab 2, which is not eligible by `follow_tab`
+        -- - `state.winnr` is now set to `nil`, but the window still exists on tab 1 (intended)
+        -- - User switches to tab 3, which is eligible by `follow_tab`
+        -- - Since there's a dap-view window elsewhere, we have to "reopen" to "follow the tab"
+        -- (otherwise, visiting a non eligible tab wouldn't make much sense - afterwards, we'd keep the "closed" state)
+        -- - We can do that just fine, since now we track the correct window with a (window) variable
+        -- - Buf if the user closes the newly opened dap-view window on tab 3, and switches back to tab 1
+        -- The original window will still be there! Since we closed, we don't want that!
+        --
+        -- This happens because the "close" function does not close all the the valid windows, only the one tracked by
+        -- `state.winnr`, which is `nil` by then (massive oversight, I know)
+        --
+        -- This never came up before the dynamic `follow_tab` because we could always assume `state.winnr` was either
+        -- from the current tab or the previous tab (which would then be handle by this very own autocmd)
+        --
+        -- By assigning `state.winnr` to the open window (which may be anywhere), `open`'s call to `close` will clean it
+        if open_winnr and state.winnr == nil then
+            state.winnr = open_winnr
+        end
+
+        if util.is_win_valid(state.winnr) and follow_tab_ then
             require("dap-view.actions").open(state.term_winnr ~= nil)
         end
 

lua/dap-view/config.lua

@@ -77,7 +77,7 @@ local M = {}
 ---@field icons dapview.IconsConfig Icons for each button
 ---@field switchbuf string|dapview.SwitchBufFun Control how to jump when selecting a breakpoint or a call in the stack
 ---@field auto_toggle boolean|"keep_terminal"
----@field follow_tab boolean Reopen dapview when switching tabs
+---@field follow_tab boolean|fun(adapter?: string): boolean Reopen dapview when switching tabs
 
 ---@type dapview.ConfigStrict
 M.config = {

lua/dap-view/setup/validate/init.lua

@@ -9,7 +9,7 @@ function M.validate(config)
         switchbuf = { config.switchbuf, { "string", "function" } },
         icons = { config.icons, "table" },
         auto_toggle = { config.auto_toggle, { "boolean", "string" } },
-        follow_tab = { config.follow_tab, "boolean" },
+        follow_tab = { config.follow_tab, { "boolean", "function" } },
     }, config)
 
     if type(config.auto_toggle) == "string" and config.auto_toggle ~= "keep_terminal" then

lua/dap-view/util/window.lua

@@ -0,0 +1,16 @@
+local api = vim.api
+
+local M = {}
+
+---@return integer?
+M.fetch_window = function()
+    for _, tabpage in ipairs(api.nvim_list_tabpages()) do
+        for _, win in ipairs(api.nvim_tabpage_list_wins(tabpage)) do
+            if vim.w[win].dapview_win then
+                return win
+            end
+        end
+    end
+end
+
+return M