feat(lib/process): update run function

lua/neotest/lib/process/init.lua

@@ -2,28 +2,62 @@ local async = require("neotest.async")
 
 local M = {}
 
+---Runs a process using libuv. This is designed for a simple, quick async alternative to io.popen and so will wait until
+---the process exits to read the stdout/stderr. Do not use this for long running jobs or for large outputs.
+---Use vim.jobstart instead.
 ---@async
----@return integer
+---@param command string[]
+---@param args table
+---@field stdout bool Read stdout
+---@field stderr bool Read stderr
+---@return integer, table Exit code and table containing stdout/stderr keys if requested
 function M.run(command, args)
   args = args or {}
   local stdin = vim.loop.new_pipe()
   local stdout = vim.loop.new_pipe()
   local stderr = vim.loop.new_pipe()
-  local result_code = async.wrap(vim.loop.spawn, 3)(command[1], {
+  local result_code
+  local send_exit, await_exit = async.control.channel.oneshot()
+
+  local handle, _ = vim.loop.spawn(command[1], {
     stdio = { stdin, stdout, stderr },
     detached = false,
     args = #command > 1 and vim.list_slice(command, 2, #command) or nil,
-  })
+  }, function(code)
+    result_code = code
+    send_exit()
+  end)
+
+  await_exit()
+  handle:close()
+
+  local stdout_data, stderr_data
+  if args.stdout then
+    local send_read, await_read = async.control.channel.oneshot()
+    stdout:read_start(function(err, data)
+      assert(not err, err)
+      stdout_data = data
+      send_read()
+    end)
+    await_read()
+  end
+  if args.stderr then
+    local send_read, await_read = async.control.channel.oneshot()
+    stderr:read_start(function(err, data)
+      assert(not err, err)
+      stderr_data = data
+      send_read()
+    end)
+    await_read()
+  end
+
   stdin:close()
   stdout:close()
   stderr:close()
-  if args.on_stdout then
-    stdout:read_start(args.on_stdout)
-  end
-  if args.on_stderr then
-    stderr:read_start(args.on_stderr)
-  end
-  return result_code
+  return result_code, {
+    stdout = stdout_data,
+    stderr = stderr_data,
+  }
 end
 
 return M

tests/unit/lib/process/init_spec.lua

@@ -0,0 +1,28 @@
+local async = require("neotest.async")
+local a = async.tests
+local lib = require("neotest.lib")
+
+describe("process lib", function()
+  describe("running a process", function()
+    a.it("returns exit code", function()
+      local result = lib.process.run({ "sh", "-c", "exit 12" })
+      assert.equal(12, result)
+    end)
+    a.it("records stdout", function()
+      local _, data = lib.process.run({ "printf", "hello" }, { stdout = true })
+      assert.equal("hello", data.stdout)
+    end)
+    a.it("doesn't records stdout", function()
+      local _, data = lib.process.run({ "printf", "hello" })
+      assert.Nil(data.stdout)
+    end)
+    a.it("records stderr", function()
+      local _, data = lib.process.run({ "sh", "-c", "printf hello >& 2" }, { stderr = true })
+      assert.equal("hello", data.stderr)
+    end)
+    a.it("doesn't record stderr", function()
+      local _, data = lib.process.run({ "sh", "-c", "printf hello >& 2" })
+      assert.Nil(data.stderr)
+    end)
+  end)
+end)