From 936ade9e46ceaea280e5e35dd6fc0c9340df94be Mon Sep 17 00:00:00 2001
From: Mathias Fussenegger <f.mathias@zignar.net>
Date: Sat, 1 Jun 2024 10:11:45 +0200
Subject: [PATCH] Use scopes from response without copy

---
 lua/dap/ext/vscode.lua |  2 +-
 lua/dap/protocol.lua   |  6 ++++++
 lua/dap/session.lua    | 37 ++++++++++++++++++++++---------------
 3 files changed, 29 insertions(+), 16 deletions(-)

diff --git a/lua/dap/ext/vscode.lua b/lua/dap/ext/vscode.lua
index 5fb120f9..d256352b 100644
--- a/lua/dap/ext/vscode.lua
+++ b/lua/dap/ext/vscode.lua
@@ -175,7 +175,7 @@ function M._load_json(jsonstr)
 end
 
 ---@param path string?
----@return Configuration[]
+---@return dap.Configuration[]
 function M.getconfigs(path)
   local resolved_path = path or (vim.fn.getcwd() .. '/.vscode/launch.json')
   if not vim.loop.fs_stat(resolved_path) then
diff --git a/lua/dap/protocol.lua b/lua/dap/protocol.lua
index 88b792f8..5668ab70 100644
--- a/lua/dap/protocol.lua
+++ b/lua/dap/protocol.lua
@@ -65,6 +65,7 @@
 ---@field stackFrames dap.StackFrame[]
 ---@field totalFrames? number
 
+
 ---@class dap.Scope
 ---@field name string
 ---@field presentationHint? "arguments"|"locals"|"registers"|string
@@ -79,6 +80,11 @@
 ---@field endColumn? number
 ---@field variables? table<string, dap.Variable> by variable name. Not part of spec
 
+
+---@class dap.ScopesResponse
+---@field scopes dap.Scope[]
+
+
 ---@class dap.ValueFormat
 ---@field hex? boolean Display the value in hex
 
diff --git a/lua/dap/session.lua b/lua/dap/session.lua
index 62a7f077..b3fc2b8d 100644
--- a/lua/dap/session.lua
+++ b/lua/dap/session.lua
@@ -760,27 +760,34 @@ end
 
 ---@param current_frame dap.StackFrame
 function Session:_request_scopes(current_frame)
-  self:request('scopes', { frameId = current_frame.id }, function(_, scopes_resp)
-    if not scopes_resp or not scopes_resp.scopes then
+  local params = {
+    frameId = current_frame.id
+  }
+  ---@param scope_resp dap.ScopesResponse?
+  local function on_scopes(_, scope_resp)
+    if not scope_resp then
       return
     end
-    current_frame.scopes = {}
-    for _, scope in pairs(scopes_resp.scopes) do
-      table.insert(current_frame.scopes, scope)
+    local scopes = scope_resp.scopes
+    current_frame.scopes = scopes
+    local function toname(var)
+      return var.name
+    end
+    for _, scope in ipairs(scopes) do
       if not scope.expensive then
-        local params = { variablesReference = scope.variablesReference }
-        self:request('variables', params, function(_, variables_resp)
-          if not variables_resp then
-            return
+
+        ---@param resp dap.VariableResponse?
+        local function on_variables(_, resp)
+          if resp then
+            scope.variables = utils.to_dict(resp.variables, toname)
           end
-          scope.variables = utils.to_dict(
-            variables_resp.variables,
-            function(v) return v.name end
-          )
-        end)
+        end
+        local varparams = { variablesReference = scope.variablesReference }
+        self:request('variables', varparams, on_variables)
       end
     end
-  end)
+  end
+  self:request('scopes', params, on_scopes)
 end