From 154de39931b3ae77248902c4adfc407b746c2fec Mon Sep 17 00:00:00 2001
From: Oscar Wallberg <oscar.wallberg@outlook.com>
Date: Sun, 28 Sep 2025 13:36:02 +0200
Subject: [PATCH] fix(dap.hover): don't show null pointers as expandable

---
 lua/ow/dap/hover/node.lua   | 32 +++++++++++++++++++++-----------
 lua/ow/dap/hover/tree.lua   | 17 ++++++-----------
 lua/ow/dap/hover/window.lua |  4 ++--
 3 files changed, 29 insertions(+), 24 deletions(-)

diff --git a/lua/ow/dap/hover/node.lua b/lua/ow/dap/hover/node.lua
index 73b8347..107e9b0 100644
--- a/lua/ow/dap/hover/node.lua
+++ b/lua/ow/dap/hover/node.lua
@@ -1,4 +1,5 @@
 ---@class ow.dap.hover.Node
+---@field lang string
 ---@field item ow.dap.Item
 ---@field parent ow.dap.hover.Node?
 ---@field children ow.dap.hover.Node[]
@@ -9,9 +10,11 @@ Node.__index = Node
 
 ---@param item ow.dap.Item
 ---@param parent ow.dap.hover.Node?
+---@param lang string
 ---@return ow.dap.hover.Node
-function Node.new(item, parent)
+function Node.new(item, parent, lang)
     return setmetatable({
+        lang = lang,
         item = item,
         parent = parent,
         children = {},
@@ -26,9 +29,14 @@ function Node:is_container()
         or false
 end
 
+function Node:is_c_lang()
+    return self.lang == "c" or self.lang == "cpp"
+end
+
 ---@return boolean
 function Node:is_c_pointer()
-    return self:is_container()
+    return self:is_c_lang()
+        and self:is_container()
         and self.item.type:match(
                 "%*%s*[const%s]*[volatile%s]*[restrict%s]*$"
             )
@@ -69,7 +77,7 @@ end
 
 ---@return boolean
 function Node:is_c_array_element()
-    return self.item.name:match("^%[?%d+%]?$") ~= nil
+    return self:is_c_lang() and self.item.name:match("^%[?%d+%]?$") ~= nil
 end
 
 ---@return string
@@ -124,10 +132,14 @@ function Node:get_full_expression()
     return expr
 end
 
----@param session dap.Session
+---@return boolean
+function Node:is_expandable()
+    return self:is_container() and not self:is_c_null_pointer()
+end
+
 ---@param content ow.dap.hover.Content
-function Node:format_into(session, content)
-    if self:is_container() then
+function Node:format_into(content)
+    if self:is_expandable() then
         local marker = self.is_expanded and "-" or "+"
         content:add(marker .. " ", "@comment")
     else
@@ -140,15 +152,13 @@ function Node:format_into(session, content)
     end
 
     local text
-    if session.filetype == "c" or session.filetype == "cpp" then
+    if self:is_c_lang() then
         text = self:format_c()
     else
-        error(
-            string.format("Formatting for %s not implemented", session.filetype)
-        )
+        error(string.format("Formatting for %s not implemented", self.lang))
     end
 
-    content:add_with_treesitter(text, session.filetype)
+    content:add_with_treesitter(text, self.lang)
 
     if self.item.value == "" then
         content:add("...", "@comment")
diff --git a/lua/ow/dap/hover/tree.lua b/lua/ow/dap/hover/tree.lua
index 6ea37a5..3733542 100644
--- a/lua/ow/dap/hover/tree.lua
+++ b/lua/ow/dap/hover/tree.lua
@@ -4,6 +4,7 @@ local Node = require("ow.dap.hover.node")
 local log = require("ow.log")
 
 ---@class ow.dap.hover.Tree
+---@field lang string
 ---@field session dap.Session
 ---@field root ow.dap.hover.Node?
 local Tree = {}
@@ -13,6 +14,7 @@ Tree.__index = Tree
 ---@return ow.dap.hover.Tree
 function Tree.new(session)
     return setmetatable({
+        lang = session.filetype,
         session = session,
         root = nil,
     }, Tree)
@@ -21,7 +23,7 @@ end
 ---@async
 ---@param item ow.dap.Item
 function Tree:build(item)
-    self.root = Node.new(item, nil)
+    self.root = Node.new(item, nil, self.lang)
 
     if self.root:is_container() then
         self:load_children(self.root)
@@ -49,7 +51,7 @@ function Tree:load_children(node)
 
     for i, var in ipairs(resp.variables) do
         local item = Item.from_var(var)
-        local child = Node.new(item, node)
+        local child = Node.new(item, node, self.lang)
         child.is_last_child = (i == #resp.variables)
 
         if item.name:match("^%d+$") then
@@ -79,7 +81,7 @@ end
 ---@param node ow.dap.hover.Node
 ---@param content ow.dap.hover.Content
 function Tree:render_subtree(node, content)
-    node:format_into(self.session, content)
+    node:format_into(content)
 
     if node.is_expanded then
         for _, child in ipairs(node.children) do
@@ -177,14 +179,7 @@ end
 ---@param node ow.dap.hover.Node
 ---@return boolean success
 function Tree:expand_all_children(node)
-    if not node:is_container() then
-        return true
-    end
-
-    if
-        (self.session.filetype == "c" or self.session.filetype == "cpp")
-        and node:is_c_null_pointer()
-    then
+    if not node:is_expandable() then
         return true
     end
 
diff --git a/lua/ow/dap/hover/window.lua b/lua/ow/dap/hover/window.lua
index 2689ad2..0e366c2 100644
--- a/lua/ow/dap/hover/window.lua
+++ b/lua/ow/dap/hover/window.lua
@@ -260,7 +260,7 @@ function Window:toggle_node()
     coroutine.wrap(function()
         local ok, err = xpcall(function()
             local info = self:get_current_node_info()
-            if not info:is_valid() or not info.node:is_container() then
+            if not info:is_valid() or not info.node:is_expandable() then
                 return
             end
 
@@ -308,7 +308,7 @@ function Window:expand_all_at_cursor()
     coroutine.wrap(function()
         local ok, err = xpcall(function()
             local info = self:get_current_node_info()
-            if not info:is_valid() or not info.node:is_container() then
+            if not info:is_valid() or not info.node:is_expandable() then
                 return
             end