feat(process): close method

doc/nio.txt

@@ -81,7 +81,7 @@ result, with the same signature as the callback for `nio.run`.
 This is useful for APIs where users don't want to create async
 contexts but which are still used in async contexts internally.
 Parameters~
-{func} `(async fun(...))`
+{func} `(async)` function
 {argc?} `(integer)` The number of arguments of func. Must be included if there
 are arguments.
 
@@ -403,13 +403,15 @@ Fields~
 {pid} `(integer)` ID of the invoked process
 {signal} `(fun(signal: integer|uv.aliases.signals))` Send a signal to the
 process
-{result} `(async fun(): number)` Wait for the process to exit and return the
-exit code
+{result} `(async fun(close: boolean): number,(string|nil)[])` Wait for the
+process to exit and return the exit code, optionally closing all streams.
 {stdin} `(nio.streams.OSStreamWriter)` Stream to write to the process stdin.
 {stdout} `(nio.streams.OSStreamReader)` Stream to read from the process
 stdout.
 {stderr} `(nio.streams.OSStreamReader)` Stream to read from the process
 stderr.
+{close} `(async fun():(string|nil)[])` Close all streams, returning any errors
+that occurred.
 
                                                              *nio.process.run()*
 `run`({opts})
@@ -422,6 +424,8 @@ Run a process asynchronously.
 
  local output = second.stdout.read()
  print(output)
+
+ process.close()
 <
 
 Processes can be chained together, passing output of one process as input to
@@ -437,6 +441,9 @@ another.
 
  local output = second.stdout.read()
  print(output)
+
+ first.close()
+ second.close()
 <
 
 The stdio fields can also be file objects.
@@ -454,6 +461,8 @@ The stdio fields can also be file objects.
 
  local output = file.read(nil, 0)
  print(output)
+
+ process.close() -- Closes the file
 <
 Parameters~
 {opts} `(nio.process.RunOpts)`

lua/nio/process.lua

@@ -11,10 +11,11 @@ nio.process = {}
 ---@class nio.process.Process
 ---@field pid integer ID of the invoked process
 ---@field signal fun(signal: integer|uv.aliases.signals) Send a signal to the process
----@field result async fun(): number Wait for the process to exit and return the exit code
+---@field result async fun(close: boolean): number,(string|nil)[] Wait for the process to exit and return the exit code, optionally closing all streams.
 ---@field stdin nio.streams.OSStreamWriter Stream to write to the process stdin.
 ---@field stdout nio.streams.OSStreamReader Stream to read from the process stdout.
 ---@field stderr nio.streams.OSStreamReader Stream to read from the process stderr.
+---@field close async fun():(string|nil)[] Close all streams, returning any errors that occurred.
 
 --- Run a process asynchronously.
 --- ```lua
@@ -24,6 +25,8 @@ nio.process = {}
 ---
 ---  local output = second.stdout.read()
 ---  print(output)
+---
+---  process.close()
 --- ```
 ---
 --- Processes can be chained together, passing output of one process as input to
@@ -39,6 +42,9 @@ nio.process = {}
 ---
 ---  local output = second.stdout.read()
 ---  print(output)
+---
+---  first.close()
+---  second.close()
 --- ```
 ---
 --- The stdio fields can also be file objects.
@@ -56,6 +62,8 @@ nio.process = {}
 ---
 ---  local output = file.read(nil, 0)
 ---  print(output)
+---
+---  process.close() -- Closes the file
 --- ```
 ---@param opts nio.process.RunOpts
 ---@return nio.process.Process? Process object for the running process
@@ -114,7 +122,8 @@ function nio.process.run(opts)
   end
 
   ---@type nio.process.Process
-  local process = {
+  local process
+  process = {
     pid = pid_or_error,
     signal = function(signal)
       vim.loop.process_kill(handle, signal)
@@ -134,7 +143,17 @@ function nio.process.run(opts)
       fd = stderr_fd,
       close = stderr.close,
     },
-    result = exit_code_future.wait,
+    result = function(close)
+      local result = exit_code_future.wait()
+      local errors = {}
+      if close then
+        errors = process.close()
+      end
+      return result, errors
+    end,
+    close = function()
+      return { stdin.close(), stdout.close(), stderr.close() }
+    end,
   }
   return process
 end

tests/process_spec.lua

@@ -196,17 +196,36 @@ describe("process", function()
   end)
 
   a.it("returns exit code", function()
-    local pipe = assert(vim.loop.new_pipe())
+    local process = assert(nio.process.run({
+      cmd = "bash",
+      args = { "-c", "exit 1" },
+    }))
 
+    local exit_code = process.result()
+    assert.equal(1, exit_code)
+  end)
+
+  a.it("with returns exit code", function()
     local process = assert(nio.process.run({
       cmd = "bash",
       args = { "-c", "exit 1" },
-      stdin = pipe,
     }))
 
-    process.signal(15)
+    local exit_code = process.with(function() end)
 
-    local exit_code = process.result()
-    assert.equal(0, exit_code)
+    assert.equal(1, exit_code)
+  end)
+
+  a.it("with closes streams", function()
+    local process = assert(nio.process.run({
+      cmd = "echo",
+      args = { "test" },
+    }))
+
+    process.with(function() end)
+
+    local stdout, stdout_err = process.stdout.read()
+    assert.equal("", stdout)
+    assert.Not.Nil(stdout_err)
   end)
 end)