fix: do not clear term on session termination (#83)

Author: igorlfs

README.md

@@ -34,7 +34,7 @@ All of that in a unified, unintrusive window.
 
 ## Getting Started
 
-Start a regular debugging session. When desired, you can use `:DapViewOpen` to start the plugin. You can switch to another section using the letter outlined in the `'winbar'` (e.g., `B` for "Breakpoints"). Explore what you can do each section by using `g?` to inspect the keymaps.
+Start a regular debugging session. When desired, you can use `:DapViewOpen` to start the plugin. You can switch to another section using the letter outlined in the `'winbar'` (e.g., `B` for "Breakpoints"). Explore what you can do in each section by using `g?` to inspect the keymaps.
 
 Once you're done debugging, you can close the plugin with `:DapViewClose` and then terminate your session as usual.
 

docs/src/routes/known-issues/+page.md

@@ -9,7 +9,3 @@ title: Known Issues
 - Can't "toggle" a breakpoint ([#74](https://github.com/igorlfs/nvim-dap-view/issues/74))
 
 These limitations stem from `nvim-dap`'s breakpoints API (or more so, from the lack of a proper one). A new API is [planned](https://github.com/mfussenegger/nvim-dap/issues/1388).
-
-## The terminal buffer is cleared right after a session finishes ([#83](https://github.com/igorlfs/nvim-dap-view/issues/83))
-
-Due to a limitation in the way multisession support is currently implemented, it's necessary to eagerly close buffers. Read [this](https://github.com/mfussenegger/nvim-dap/discussions/1523) discussion for details.

lua/dap-view/events.lua

@@ -22,20 +22,8 @@ dap.listeners.on_session[SUBSCRIPTION_ID] = function(_, new)
         state.current_session_id = new.id
         state.current_adapter = new.config.type
 
-        -- Avoid creating useless buffers for child sessions
-        if new.parent == nil then
-            if not state.term_bufnrs[new.id] then
-                state.term_bufnrs[new.id] = term.setup_term_win_cmd()
-
-                if not (term_config.start_hidden or vim.tbl_contains(config.winbar.sections, "console")) then
-                    term.open_term_buf_win()
-                end
-            end
-        else
-            state.term_bufnrs[new.id] = state.term_bufnrs[new.parent.id]
-        end
-
-        if not vim.tbl_contains(term_config.hide, state.current_adapter) then
+        -- Handle switching the buf if session is already initialized
+        if new.term_buf and not vim.tbl_contains(term_config.hide, state.current_adapter) then
             term.switch_term_buf()
         end
 
@@ -58,6 +46,25 @@ dap.listeners.after.configurationDone[SUBSCRIPTION_ID] = function()
     -- Sync exception breakpoints for the newly initialized session
     -- The downside is that not all adapters support `configurationDone` :/
     require("dap-view.exceptions").update_exception_breakpoints_filters()
+
+    local config = setup.config
+    local term_config = config.windows.terminal
+
+    local has_console = vim.tbl_contains(config.winbar.sections, "console")
+    local hidden_adapter = vim.tbl_contains(term_config.hide, state.current_adapter)
+    local open_term = not term_config.start_hidden and not has_console and not hidden_adapter
+
+    -- We can't setup inside `on_session` hook because at that stage the session does not have a `term_buf`
+    term.setup_term_buf()
+
+    -- `term_buf` must be setup before calling open
+    if open_term then
+        term.open_term_buf_win()
+    end
+
+    if not hidden_adapter then
+        term.switch_term_buf()
+    end
 end
 
 dap.listeners.after.setBreakpoints[SUBSCRIPTION_ID] = function()
@@ -142,7 +149,7 @@ dap.listeners.after.initialize[SUBSCRIPTION_ID] = function(session)
     end
 end
 
-dap.listeners.after.event_terminated[SUBSCRIPTION_ID] = function(session)
+dap.listeners.after.event_terminated[SUBSCRIPTION_ID] = function()
     -- Refresh threads view on exit to avoid showing outdated trace
     if state.current_section == "threads" then
         threads.show()
@@ -159,17 +166,6 @@ dap.listeners.after.event_terminated[SUBSCRIPTION_ID] = function(session)
         end
     end
 
-    -- TODO find a cleaner way to dispose of these buffers
-    local term_bufnr = state.term_bufnrs[session.id]
-    if util.is_buf_valid(term_bufnr) then
-        vim.api.nvim_buf_delete(term_bufnr, { force = true })
-    end
-    for k, v in pairs(state.term_bufnrs) do
-        if v == term_bufnr then
-            state.term_bufnrs[k] = nil
-        end
-    end
-
     winbar.redraw_controls()
 end
 

lua/dap-view/state.lua

@@ -22,7 +22,6 @@
 ---@class dapview.State
 ---@field bufnr? integer
 ---@field winnr? integer
----@field term_bufnrs {[number]: number}
 ---@field term_winnr? integer
 ---@field last_term_winnr? integer
 ---@field threads_filter string
@@ -40,7 +39,6 @@
 ---@field watched_expressions table<string, dapview.ExpressionPack>
 ---@field cur_pos table<dapview.DefaultSection,integer?>
 local M = {
-    term_bufnrs = {},
     threads_filter = "",
     threads_filter_invert = false,
     exceptions_options = {},

lua/dap-view/term/init.lua

@@ -15,11 +15,14 @@ M.show = function()
         return
     end
 
-    assert(state.current_session_id, "has active session")
+    local session = dap.session()
+
+    assert(session ~= nil, "has active session")
+    assert(session.term_buf, "session has term")
 
     api.nvim_win_call(state.winnr, function()
         vim.wo[state.winnr][0].winfixbuf = false
-        api.nvim_set_current_buf(state.term_bufnrs[state.current_session_id])
+        api.nvim_set_current_buf(session.term_buf)
         vim.wo[state.winnr][0].winfixbuf = true
     end)
 
@@ -41,10 +44,18 @@ end
 ---III. There's no term win or it is invalid
 ---@return integer?
 M.open_term_buf_win = function()
-    if not state.current_session_id then
+    local session = require("dap").session()
+
+    if session == nil then
+        return nil
+    end
+
+    local term_bufnr = session.term_buf
+
+    if term_bufnr == nil then
+        vim.notify_once("No terminal for the current session")
         return nil
     end
-    local term_bufnr = state.term_bufnrs[state.current_session_id]
 
     local windows_config = setup.config.windows
     local term_config = setup.config.windows.terminal
@@ -74,13 +85,17 @@ M.open_term_buf_win = function()
     return state.term_winnr
 end
 
----Create a term buf and setup nvim-dap's `terminal_win_cmd` to use it
-M.setup_term_win_cmd = function()
-    -- Can't use an unlisted term buffers
-    -- See https://github.com/igorlfs/nvim-dap-view/pull/37#issuecomment-2785076872
-    local term_bufnr = api.nvim_create_buf(true, false)
+M.setup_term_buf = function()
+    local session = dap.session()
+
+    assert(session ~= nil, "has active session")
 
-    assert(term_bufnr ~= 0, "Failed to create dap-view-term buffer")
+    local term_bufnr = session.term_buf
+
+    if term_bufnr == nil then
+        vim.notify("No terminal for the current session")
+        return
+    end
 
     -- We have to set the filetype for each term buf to avoid issues when calling switch_term_buf
     -- See https://github.com/igorlfs/nvim-dap-view/issues/69
@@ -91,25 +106,28 @@ M.setup_term_win_cmd = function()
     end
 
     require("dap-view.term.scroll").scroll(term_bufnr)
-
-    dap.defaults.fallback.terminal_win_cmd = function()
-        return term_bufnr
-    end
-
-    return term_bufnr
 end
 
 M.switch_term_buf = function()
     local has_console = vim.tbl_contains(setup.config.winbar.sections, "console")
     local winnr = (has_console and state.winnr) or state.term_winnr
     local is_console_active = state.current_section == "console"
 
+    local session = dap.session()
+
+    assert(session ~= nil, "has active session")
+
+    if session.term_buf == nil then
+        vim.notify_once("No terminal for the current session")
+        return
+    end
+
     if util.is_win_valid(winnr) and (is_console_active or not has_console) then
         ---@cast winnr integer
 
         api.nvim_win_call(winnr, function()
             vim.wo[winnr][0].winfixbuf = false
-            api.nvim_set_current_buf(state.term_bufnrs[state.current_session_id])
+            api.nvim_set_current_buf(session.term_buf)
             vim.wo[winnr][0].winfixbuf = true
 
             if is_console_active then

lua/dap-view/term/options.lua

@@ -2,7 +2,8 @@ local M = {}
 
 ---@param winnr integer
 M.set_win_options = function(winnr)
-    local win = vim.wo[winnr][0]
+    -- We actually want other buffers (e.g, term_bufs from other sessions) to inherit these options
+    local win = vim.wo[winnr]
     win.scrolloff = 0
     win.wrap = false
     win.number = false

plugin/dap-view.lua

@@ -1,3 +1,6 @@
+-- Let nvim-dap handle terminal buffers internally without interfering in the layout
+require("dap").defaults.fallback.terminal_win_cmd = nil
+
 local command = vim.api.nvim_create_user_command
 
 command("DapViewOpen", function()