fix: guard vim.lsp.diagnostics.refresh() against nil

Neovim 0.12+ restructured LSP internals; vim.lsp.diagnostics no
longer exists as a submodule. Guard the call so :SCLRescanWorkspaceTypes
doesn't crash on startup.

AGENTS.md

@@ -17,7 +17,7 @@ lua test/test_fb.lua         # Run FB parser tests
 lua test/test_integration.lua # Run integration tests
 
 # Reference Project
-# Tests use files from: ~/dev/siemens/projects/scl_lang_support_lazyvim_ref_project/
+# Tests use files from: ~/Documents/siemens/scl_lang_support_lazyvim_ref_project/
 # Override with: SCL_REF_PROJECT=/path/to/ref lua tests/run_tests.lua
 ```
 
@@ -158,7 +158,7 @@ The LSP validates data types and provides warnings for unknown types:
 
 Use the reference project for testing:
 ```
-~/dev/siemens/projects/scl_lang_support_lazyvim_ref_project/
+~/Documents/siemens/scl_lang_support_lazyvim_ref_project/
 ```
 
 Contains `.scl`, `.db`, `.udt`, and `.xml` files for comprehensive testing of:

README.md

@@ -11,7 +11,7 @@ A Neovim/LazyVim plugin that launches the [`tia-lsp`](https://gitea.l-tech.rs/la
 | **Tab Navigation** | Jump between parameters with `<Tab>` in insert mode |
 | **Workspace UDT Scanner** | Scans project for user-defined types (.udt files) |
 | **Workspace Global DB Scanner** | Scans project for global data blocks (.db files) |
-| **blink.cmp Integration** | Smart completion source for blink.cmp |
+| **blink.cmp Integration** | Smart completion source for blink.cmp — DB members, FB parameters, built-in types (IEC_TIMER IN/PT/Q/ET), nested UDT/array-of-UDT path resolution |
 | **Attribute Block Toggle** | Interactive expand/collapse of `{...}` blocks with `<Leader>xa` |
 | **Tree-sitter Highlighting** | Syntax highlighting via tree-sitter queries |
 
@@ -105,7 +105,33 @@ return {
 }
 ```
 
-**Step 5: Verify**
+**Step 5: Configure blink.cmp defaults**
+
+The `scl` completion source must be listed in blink.cmp's `sources.default` with the corresponding provider definition. Create or update your blink.cmp config:
+
+```lua
+-- ~/.config/nvim/lua/plugins/blink.lua (or extend your existing blink.cmp spec)
+return {
+  "saghen/blink.cmp",
+  optional = true,
+  opts = {
+    sources = {
+      default = { "lsp", "path", "snippets", "buffer", "scl" },
+      providers = {
+        scl = {
+          name = "scl",
+          module = "tia.blink_cmp_source",
+          score_offset = 100,
+        },
+      },
+    },
+  },
+}
+```
+
+> **Why this is needed:** blink.cmp only queries sources listed in `sources.default`. Without `"scl"` there, the DB member and built-in type completions (e.g., `"MyDB".myField` or `#myTimer.IN`) will not appear.
+
+**Step 6: Verify**
 
 Open a `.scl` file and run `:LspInfo`. `tia_lsp` should be attached. Run `:checkhealth` for detailed diagnostics.
 

lua/tia/attr_toggle.lua

@@ -112,54 +112,44 @@ function M.expand_all_attr_blocks(opts)
   end
 end
 
--- Helper to make a pattern case-insensitive
-local function case_insensitive_pattern(pattern)
-  return pattern:gsub("(%a)", function(c)
-    return "[" .. c:upper() .. c:lower() .. "]"
-  end)
+-- Find the last line of the declaration section based on filetype
+local function get_declaration_end(lines, ft)
+  if ft == "udt" then
+    return #lines
+  end
+  for i, line in ipairs(lines) do
+    if line:match("^%s*BEGIN%s*$") then
+      return i - 1
+    end
+  end
+  return #lines
 end
 
--- Collapse all attribute blocks matching patterns in current buffer
-function M.collapse_all_attr_blocks(patterns)
-  patterns = patterns or {
-    case_insensitive_pattern("^%s*EXTERNAL"),     -- EXTERNALACCESSIBLE, EXTERNALVISIBLE
-    case_insensitive_pattern("^%s*S7_"),          -- S7_Optimized_Access
-    case_insensitive_pattern("^%s*NonRetain"),    -- NonRetain
-    case_insensitive_pattern("^%s*Retain"),       -- Retain (but not NonRetain)
-    "^%s*%w+%s*:=",                                -- key := value
-    "^%s*%w+%s*$",                                 -- single word attribute
-  }
-  
+-- Collapse all {...} blocks in the declaration section of current buffer
+function M.collapse_all_attr_blocks()
   local bufnr = vim.api.nvim_get_current_buf()
+  local ft = vim.bo[bufnr].filetype
   local lines = vim.api.nvim_buf_get_lines(bufnr, 0, -1, false)
   local count = 0
-  
-  -- Initialize buffer state
+
+  local decl_end = get_declaration_end(lines, ft)
+
   if not buffer_attr_state[bufnr] then
     buffer_attr_state[bufnr] = {}
   end
-  
-  for line_idx, line in ipairs(lines) do
+
+  for line_idx = 1, decl_end do
+    local line = lines[line_idx]
     local pos = 1
     while pos <= #line do
-      local start_pos, end_pos, capture = line:find("{(.-)}", pos)
+      local start_pos, end_pos = line:find("{(.-)}", pos)
       if not start_pos then
         break
       end
-      
+
       local content = line:sub(start_pos + 1, end_pos - 1)
 
-      -- Check if content matches any pattern
-      local should_collapse = false
-      for _, pattern in ipairs(patterns) do
-        if content:match(pattern) then
-          should_collapse = true
-          break
-        end
-      end
-      
-      -- Don't collapse if already collapsed
-      if should_collapse and content ~= "..." then
+      if content ~= "..." then
         local state_key = line_idx .. "_" .. start_pos
         buffer_attr_state[bufnr][state_key] = {
           collapsed = "...",
@@ -168,21 +158,17 @@ function M.collapse_all_attr_blocks(patterns)
           line_num = line_idx,
           start_col = start_pos,
         }
-        
-        -- Replace in line
+
         line = line:sub(1, start_pos) .. "..." .. line:sub(end_pos)
         count = count + 1
-        
-        -- Update position for next search
         pos = start_pos + 4
       else
         pos = end_pos + 1
       end
     end
-    
     lines[line_idx] = line
   end
-  
+
   vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, lines)
   vim.notify("Collapsed " .. count .. " attribute block(s)", vim.log.levels.INFO)
 end

lua/tia/blink_cmp_source.lua

@@ -239,10 +239,16 @@ function M:get_completions(context, callback)
     local db_parser = require("tia.db_parser")
     local db_name = active_portion:match('"([%w_]+)"')
     
+    -- Ensure cache is populated
+    if db_name and db_parser.get_cache_count() == 0 then
+      local ws = require("tia.workspace_types")
+      ws.scan_project_dbs(bufnr)
+    end
+    
     if db_name then
       local db = db_parser.get_db(db_name)
       if db then
-        local path = active_portion:match('"[^"]+%"%.([%w_.]*)')
+        local path = active_portion:match('"[^"]+"%.([%w_.]*)$')
         
         -- Resolve nested path through DB members
         local current_type = nil
@@ -269,15 +275,23 @@ function M:get_completions(context, callback)
             
             if found_member then
               resolved_path = part
+              local nested_type = nil
               if found_member.is_udt then
-                -- This member is a UDT type, continue resolving
+                nested_type = found_member.type
+              else
+                -- Check for array of UDT: Array[..] of "TypeName"
+                local array_udt = found_member.raw_type:match('Array%b[]%s*of%s*"([^"]+)"')
+                if array_udt then
+                  nested_type = array_udt
+                end
+              end
+              if nested_type then
                 local udt_parser = require("tia.udt_parser")
-                current_members = udt_parser.get_udt_members(found_member.type)
-                current_type = found_member.type
+                current_members = udt_parser.get_udt_members(nested_type)
+                current_type = nested_type
               else
                 -- This is a basic type, can't continue
                 if i < #path_parts then
-                  -- There are more parts but this isn't a UDT
                   found = false
                   break
                 end
@@ -319,14 +333,11 @@ function M:get_completions(context, callback)
               detail = m.raw_type,
             })
           end
-          local wrapped_callback = vim.schedule_wrap(function(response)
-            callback({
-              items = response.items,
-              is_incomplete_backward = false,
-              is_incomplete_forward = false,
-            })
-          end)
-          wrapped_callback({ items = items })
+          callback({
+            items = items,
+            is_incomplete_backward = false,
+            is_incomplete_forward = false,
+          })
           return
         end
       end
@@ -959,6 +970,28 @@ function M:get_completions(context, callback)
     end
 
     if not is_udt and not is_fb then
+      -- Check built-in instructions (IEC_TIMER, TON, etc.)
+      local builtin = require("tia.builtin_instructions")
+      local builtin_params = builtin.get_parameters(var_type)
+      if builtin_params then
+        local items = {}
+        for _, inp in ipairs(builtin_params.inputs or {}) do
+          table.insert(items, {
+            label = inp.name,
+            kind = vim.lsp.protocol.CompletionItemKind.Field,
+            detail = (inp.type or "ANY") .. " (Input)",
+          })
+        end
+        for _, out in ipairs(builtin_params.outputs or {}) do
+          table.insert(items, {
+            label = out.name,
+            kind = vim.lsp.protocol.CompletionItemKind.Field,
+            detail = (out.type or "ANY") .. " (Output)",
+          })
+        end
+        wrapped_callback({ items = items })
+        return
+      end
       wrapped_callback({ items = {} })
       return
     end

lua/tia_lsp/init.lua

@@ -177,17 +177,18 @@ function M.setup_syntax(opts)
 	if opts.cmp then
 		local function try_register()
 			local cmp_ok, cmp = pcall(require, "blink.cmp")
-			local blink_source_ok, blink_source = pcall(require, "tia.blink_cmp_source")
-			if cmp_ok and cmp and cmp.add_source_provider and blink_source_ok then
-				local source_config = {
-					name = "scl",
-					provider = blink_source,
-					score_offset = 100,
-				}
-				pcall(cmp.add_source_provider, "scl", source_config)
-				pcall(cmp.add_filetype_source, "scl", "scl")
-
-				vim.notify("SCL: blink.cmp source registered", vim.log.levels.INFO)
+			local blink_source_ok = pcall(require, "tia.blink_cmp_source")
+			if cmp_ok and cmp and blink_source_ok then
+				if cmp.add_source_provider then
+					local blink_source = require("tia.blink_cmp_source")
+					local source_config = {
+						name = "scl",
+						provider = blink_source,
+						score_offset = 100,
+					}
+					pcall(cmp.add_source_provider, "scl", source_config)
+					pcall(cmp.add_filetype_source, "scl", "scl")
+				end
 				return true
 			end
 			return false
@@ -325,6 +326,21 @@ function M.rescan_workspace_types()
 			.. fb_result.total_files,
 		vim.log.levels.INFO
 	)
+
+	local clients = vim.lsp.get_clients({ name = "tia_lsp" })
+	for _, client in ipairs(clients) do
+		client.request("workspace/executeCommand", {
+			command = "SCLRescanWorkspaceTypes",
+		}, function(err, _)
+			if err then
+				vim.notify("SCL RescanWorkspaceTypes LSP error: " .. err.message, vim.log.levels.ERROR)
+			end
+		end, 0)
+	end
+
+	if vim.lsp.diagnostics then
+		vim.lsp.diagnostics.refresh()
+	end
 end
 
 function M.create_commands()