From c9ba8281b0e093716a66c6a40c5ab0b79236515d Mon Sep 17 00:00:00 2001
From: Barrett Ruth <br.barrettruth@gmail.com>
Date: Fri, 3 Oct 2025 09:16:38 -0400
Subject: [PATCH] fix(runner): proper timeout

---
 README.md                    |  1 +
 lua/cp/runner/execute.lua    | 40 ++++++--------------
 lua/cp/runner/run_render.lua | 10 ++---
 lua/cp/utils.lua             | 72 ++++++++++++++++++++++++++++++++++--
 4 files changed, 86 insertions(+), 37 deletions(-)

diff --git a/README.md b/README.md
index 9249a17..dbbafe4 100644
--- a/README.md
+++ b/README.md
@@ -19,6 +19,7 @@ https://github.com/user-attachments/assets/50b19481-8e6d-47b4-bebc-15e16c61a9c9
 
 - [uv](https://docs.astral.sh/uv/) for problem scraping
 - [LuaSnip](https://github.com/L3MON4D3/LuaSnip) for templates
+- GNU [time](https://www.gnu.org/software/time/) and [timeout](https://www.gnu.org/software/coreutils/manual/html_node/timeout-invocation.html)
 
 ## Quick Start
 
diff --git a/lua/cp/runner/execute.lua b/lua/cp/runner/execute.lua
index 72f41f4..6d7b712 100644
--- a/lua/cp/runner/execute.lua
+++ b/lua/cp/runner/execute.lua
@@ -74,10 +74,7 @@ local function parse_and_strip_time_v(output, memory_mb)
     end
   end
   if not timing_idx then
-    while #lines > 0 and lines[#lines]:match('^%s*$') do
-      table.remove(lines, #lines)
-    end
-    return table.concat(lines, '\n'), 0, false
+    return output or '', 0, false
   end
 
   local start_idx = timing_idx
@@ -110,20 +107,22 @@ local function parse_and_strip_time_v(output, memory_mb)
 end
 
 function M.run(cmd, stdin, timeout_ms, memory_mb)
-  local prog = table.concat(cmd, ' ')
-  local pre = {}
-  if memory_mb and memory_mb > 0 then
-    table.insert(pre, ('ulimit -v %d'):format(memory_mb * 1024))
-  end
-  local prefix = (#pre > 0) and (table.concat(pre, '; ') .. '; ') or ''
   local time_bin = utils.time_path()
-  local sh = prefix .. ('%s -v sh -c %q 2>&1'):format(time_bin, prog)
+  local timeout_bin = utils.timeout_path()
+
+  local prog = table.concat(cmd, ' ')
+  local pre = {
+    ('ulimit -v %d'):format(memory_mb * 1024),
+  }
+  local prefix = table.concat(pre, '; ') .. '; '
+  local sec = math.ceil(timeout_ms / 1000)
+  local timeout_prefix = ('%s -k 1s %ds '):format(timeout_bin, sec)
+  local sh = prefix .. timeout_prefix .. ('%s -v sh -c %q 2>&1'):format(time_bin, prog)
 
   local t0 = vim.uv.hrtime()
   local r = vim
     .system({ 'sh', '-c', sh }, {
       stdin = stdin,
-      timeout = timeout_ms,
       text = true,
     })
     :wait()
@@ -131,7 +130,7 @@ function M.run(cmd, stdin, timeout_ms, memory_mb)
 
   local code = r.code or 0
   local raw = r.stdout or ''
-  local cleaned, peak_mb = parse_and_strip_time_v(raw)
+  local cleaned, peak_mb, mled = parse_and_strip_time_v(raw, memory_mb)
   local tled = code == 124
 
   local signal = nil
@@ -139,21 +138,6 @@ function M.run(cmd, stdin, timeout_ms, memory_mb)
     signal = constants.signal_codes[code]
   end
 
-  local lower = (cleaned or ''):lower()
-  local oom_hint = lower:find('std::bad_alloc', 1, true)
-    or lower:find('cannot allocate memory', 1, true)
-    or lower:find('enomem', 1, true)
-
-  local near_cap = false
-  if memory_mb and memory_mb > 0 then
-    near_cap = (peak_mb >= (0.90 * memory_mb))
-  end
-
-  local mled = false
-  if peak_mb >= memory_mb or near_cap or oom_hint then
-    mled = true
-  end
-
   if tled then
     logger.log(('Execution timed out in %.1fms.'):format(dt))
   elseif mled then
diff --git a/lua/cp/runner/run_render.lua b/lua/cp/runner/run_render.lua
index 42de606..2c05c15 100644
--- a/lua/cp/runner/run_render.lua
+++ b/lua/cp/runner/run_render.lua
@@ -30,19 +30,17 @@ function M.get_status_info(ran_test_case)
     return { text = 'AC', highlight_group = 'CpTestAC' }
   end
 
-  if ran_test_case.actual == '' then
-    return { text = '...', highlight_group = 'CpTestPending' }
-  end
-
   if ran_test_case.tled then
     return { text = 'TLE', highlight_group = 'CpTestTLE' }
   elseif ran_test_case.mled then
     return { text = 'MLE', highlight_group = 'CpTestMLE' }
-  elseif ran_test_case.code and ran_test_case.code >= 128 then
+  elseif ran_test_case.code > 0 and ran_test_case.code >= 128 then
     return { text = 'RTE', highlight_group = 'CpTestRTE' }
-  else
+  elseif ran_test_case.code == 0 and not ran_test_case.ok then
     return { text = 'WA', highlight_group = 'CpTestWA' }
   end
+
+  return { text = '...', highlight_group = 'CpTestPending' }
 end
 
 local function format_exit_code(code)
diff --git a/lua/cp/utils.lua b/lua/cp/utils.lua
index 033c924..c3ff310 100644
--- a/lua/cp/utils.lua
+++ b/lua/cp/utils.lua
@@ -7,6 +7,9 @@ local uname = vim.loop.os_uname()
 local _time_cached = false
 local _time_path = nil
 local _time_reason = nil
+local _timeout_cached = false
+local _timeout_path = nil
+local _timeout_reason = nil
 
 local function is_windows()
   return uname and uname.sysname == 'Windows_NT'
@@ -146,9 +149,14 @@ function M.check_required_runtime()
     return false, 'Neovim 0.10.0+ required'
   end
 
-  local cap = M.time_capability()
-  if not cap.ok then
-    return false, 'GNU time not found: ' .. (cap.reason or '')
+  local time = M.time_capability()
+  if not time.ok then
+    return false, 'GNU time not found: ' .. (time.reason or '')
+  end
+
+  local timeout = M.timeout_capability()
+  if not timeout.ok then
+    return false, 'GNU timeout not found: ' .. (timeout.reason or '')
   end
 
   if vim.fn.executable('uv') ~= 1 then
@@ -162,4 +170,62 @@ function M.check_required_runtime()
   return true
 end
 
+local function check_timeout_is_gnu_timeout(bin)
+  if vim.fn.executable(bin) ~= 1 then
+    return false
+  end
+  local r = vim.system({ bin, '--version' }, { text = true }):wait()
+  if r and r.code == 0 and r.stdout then
+    local s = r.stdout:lower()
+    if s:find('gnu coreutils', 1, true) or s:find('timeout %(gnu coreutils%)', 1, true) then
+      return true
+    end
+  end
+  return false
+end
+
+local function find_gnu_timeout()
+  if _timeout_cached then
+    return _timeout_path, _timeout_reason
+  end
+
+  if is_windows() then
+    _timeout_cached = true
+    _timeout_path = nil
+    _timeout_reason = 'unsupported on Windows'
+    return _timeout_path, _timeout_reason
+  end
+
+  local candidates
+  if uname and uname.sysname == 'Darwin' then
+    candidates = { 'gtimeout', '/opt/homebrew/bin/gtimeout', '/usr/local/bin/gtimeout' }
+  else
+    candidates = { '/usr/bin/timeout', 'timeout' }
+  end
+
+  for _, bin in ipairs(candidates) do
+    if check_timeout_is_gnu_timeout(bin) then
+      _timeout_cached = true
+      _timeout_path = bin
+      _timeout_reason = nil
+      return _timeout_path, _timeout_reason
+    end
+  end
+
+  _timeout_cached = true
+  _timeout_path = nil
+  _timeout_reason = 'GNU timeout not found (install `coreutils`; macOS: `brew install coreutils`)'
+  return _timeout_path, _timeout_reason
+end
+
+function M.timeout_path()
+  local path = find_gnu_timeout()
+  return path
+end
+
+function M.timeout_capability()
+  local path, reason = find_gnu_timeout()
+  return { ok = path ~= nil, path = path, reason = reason }
+end
+
 return M