From 94181ad7dcb75e1e188164276696434e03302a21 Mon Sep 17 00:00:00 2001
From: mohsen <36933074+smoka7@users.noreply.github.com>
Date: Wed, 8 Jun 2022 23:25:39 +0430
Subject: [PATCH] fix(diagnostic): check for negative column value (#18868)

---
 runtime/lua/vim/diagnostic.lua          | 11 ++++++++++-
 test/functional/lua/diagnostic_spec.lua | 13 +++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/runtime/lua/vim/diagnostic.lua b/runtime/lua/vim/diagnostic.lua
index bb12362234..afc0a4095c 100644
--- a/runtime/lua/vim/diagnostic.lua
+++ b/runtime/lua/vim/diagnostic.lua
@@ -398,10 +398,19 @@ local function get_diagnostics(bufnr, opts, clamp)
     if not opts.lnum or d.lnum == opts.lnum then
       if clamp and vim.api.nvim_buf_is_loaded(b) then
         local line_count = buf_line_count[b] - 1
-        if d.lnum > line_count or d.end_lnum > line_count or d.lnum < 0 or d.end_lnum < 0 then
+        if
+          d.lnum > line_count
+          or d.end_lnum > line_count
+          or d.lnum < 0
+          or d.end_lnum < 0
+          or d.col < 0
+          or d.end_col < 0
+        then
           d = vim.deepcopy(d)
           d.lnum = math.max(math.min(d.lnum, line_count), 0)
           d.end_lnum = math.max(math.min(d.end_lnum, line_count), 0)
+          d.col = math.max(d.col, 0)
+          d.end_col = math.max(d.end_col, 0)
         end
       end
       table.insert(diagnostics, d)
diff --git a/test/functional/lua/diagnostic_spec.lua b/test/functional/lua/diagnostic_spec.lua
index 7f929db8bf..f9647f5b6a 100644
--- a/test/functional/lua/diagnostic_spec.lua
+++ b/test/functional/lua/diagnostic_spec.lua
@@ -729,6 +729,19 @@ describe('vim.diagnostic', function()
         return vim.diagnostic.get_next_pos { namespace = diagnostic_ns }
       ]])
     end)
+
+    it('works with diagnostics before the start of the line', function()
+    eq({4, 0}, exec_lua [[
+    vim.diagnostic.set(diagnostic_ns, diagnostic_bufnr, {
+        make_error('Diagnostic #1', 3, 9001, 3, 9001),
+        make_error('Diagnostic #2', 4, -1, 4, -1),
+    })
+    vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
+    vim.api.nvim_win_set_cursor(0, {1, 1})
+    vim.diagnostic.goto_next { float = false }
+    return vim.diagnostic.get_next_pos { namespace = diagnostic_ns }
+    ]])
+end)
   end)
 
   describe('get_prev_pos()', function()