From 5205819201ee245c9428959bca4028da508d09f5 Mon Sep 17 00:00:00 2001
From: Lazar Bulovan <lazar.bulovan@l-tech.biz>
Date: Wed, 22 Jul 2026 17:43:18 +0200
Subject: [PATCH] feat: remove unassigned output params in formatter + SCL006
 diagnostic

- Formatter now strips unassigned output params (e.g. Q =>, ET =>)
  from FB/FC calls during formatting.
- Diagnostics now produce SCL006 warning for unassigned output params.
- Also converted src/ symlinks for diagnostics.lua and formatter.lua
  in mason package so all three files stay in sync.
---
 src/diagnostics.lua | 11 +++++++++++
 src/formatter.lua   |  9 +++++++++
 2 files changed, 20 insertions(+)

diff --git a/src/diagnostics.lua b/src/diagnostics.lua
index d5cfd36..ed86057 100644
--- a/src/diagnostics.lua
+++ b/src/diagnostics.lua
@@ -254,6 +254,17 @@ function M.validate_diagnostics(content, workspace_types, root_dir)
     if trimmed:match("^%s*//") or trimmed:match("^%s*%(%*") then
       -- Skip comments
     else
+      -- Check for unassigned output parameters in FB/FC calls (e.g. "Q =>")
+      for unassigned in line:gmatch("([%w_]+)%s*=>%s*[,%)]") do
+        table.insert(diagnostics, {
+          range = range_to_lsp(line_num, line:find(unassigned, 1, true) - 1, line_num, line:find(unassigned, 1, true) + #unassigned),
+          severity = DiagnosticSeverity.Warning,
+          message = string.format("Unassigned output parameter: %s =>", unassigned),
+          code = "SCL006",
+          source = "tia_lsp",
+        })
+      end
+
       for assignment in line:gmatch("#[%w_]+%s*:=") do
         local var_name = assignment:match("#([%w_]+)")
         if var_name and in_var_section then
diff --git a/src/formatter.lua b/src/formatter.lua
index 0c31905..3843873 100644
--- a/src/formatter.lua
+++ b/src/formatter.lua
@@ -261,6 +261,15 @@ function M.format_document(content, options)
       table.insert(params, last_param)
     end
     
+    -- Remove unassigned output parameters (e.g. "Q =>", "ET =>")
+    local filtered = {}
+    for _, p in ipairs(params) do
+      if not p:match("^[%w_]+%s*=>%s*$") then
+        table.insert(filtered, p)
+      end
+    end
+    params = filtered
+    
     if #params == 0 then
       return { base_indent .. fb_name .. "();" }
     end