Nim/tests/stdlib/tosproc.nim

# test the osproc module

import stdtest/[specialpaths, unittest_light]

when defined(case_testfile): # compiled test file for child process
  from posix import exitnow
  proc c_exit2(code: c_int): void {.importc: "_exit", header: "<unistd.h>".}
  import os
  var a = 0
  proc fun(b = 0) =
    a.inc
    if a mod 10000000 == 0: # prevents optimizing it away
      echo a
    fun(b+1)

  proc main() =
    let args = commandLineParams()
    echo (msg: "child binary", pid: getCurrentProcessId())
    let arg = args[0]
    echo (arg: arg)
    case arg
    of "exit_0":
      if true: quit(0)
    of "exitnow_139":
      if true: exitnow(139)
    of "c_exit2_139":
      if true: c_exit2(139)
    of "quit_139":
      # `exitStatusLikeShell` doesn't distinguish between a process that
      # exit(139) and a process that gets killed with `SIGSEGV` because
      # 139 = 11 + 128 = SIGSEGV + 128.
      # However, as #10249 shows, this leads to bad debugging experience
      # when a child process dies with SIGSEGV, leaving no trace of why it
      # failed. The shell (and lldb debugger) solves that by inserting a
      # helpful msg: `segmentation fault` when it detects a signal killed
      # the child.
      # todo: expose an API that will show more diagnostic, returning
      # (exitCode, signal) instead of just `shellExitCode`.
      if true: quit(139)
    of "exit_recursion": # stack overflow by infinite recursion
      fun()
      echo a
    of "exit_array": # bad array access
      echo args[1]
  main()

else:

  import os, osproc, strutils
  const nim = getCurrentCompilerExe()

  block execShellCmdTest:
    ## first, compile child program
    const sourcePath = currentSourcePath()
    let output = buildDir / "D20190111T024543".addFileExt(ExeExt)
    let cmd = "$# c -o:$# -d:release -d:case_testfile $#" % [nim, output,
        sourcePath]
    # we're testing `execShellCmd` so don't rely on it to compile test file
    # note: this should be exported in posix.nim
    proc c_system(cmd: cstring): cint {.importc: "system",
      header: "<stdlib.h>".}
    assertEquals c_system(cmd), 0

    ## use it
    template runTest(arg: string, expected: int) =
      echo (arg2: arg, expected2: expected)
      assertEquals execShellCmd(output & " " & arg), expected

    runTest("exit_0", 0)
    runTest("exitnow_139", 139)
    runTest("c_exit2_139", 139)
    runTest("quit_139", 139)

  block execProcessTest:
    let dir = parentDir(currentSourcePath())
    let (_, err) = execCmdEx(nim & " c " & quoteShell(dir / "osproctest.nim"))
    doAssert err == 0
    let exePath = dir / addFileExt("osproctest", ExeExt)
    let outStr1 = execProcess(exePath, workingDir = dir, args = ["foo",
        "b A r"], options = {})
    doAssert outStr1 == dir & "\nfoo\nb A r\n"

    const testDir = "t e st"
    createDir(testDir)
    doAssert dirExists(testDir)
    let outStr2 = execProcess(exePath, workingDir = testDir, args = ["x yz"],
        options = {})
    doAssert outStr2 == absolutePath(testDir) & "\nx yz\n"

    removeDir(testDir)
    try:
      removeFile(exePath)
    except OSError:
      discard

  import std/streams
  block: # test for startProcess (more tests needed)
    # bugfix: windows stdin.close was a noop and led to blocking reads
    proc startProcessTest(command: string, options: set[ProcessOption] = {
                    poStdErrToStdOut, poUsePath}, input = ""): tuple[
                    output: TaintedString,
                    exitCode: int] {.tags:
                    [ExecIOEffect, ReadIOEffect, RootEffect], gcsafe.} =
      var p = startProcess(command, options = options + {poEvalCommand})
      var outp = outputStream(p)
      if input.len > 0: inputStream(p).write(input)
      close inputStream(p)
      result = (TaintedString"", -1)
      var line = newStringOfCap(120).TaintedString
      while true:
        if outp.readLine(line):
          result[0].string.add(line.string)
          result[0].string.add("\n")
        else:
          result[1] = peekExitCode(p)
          if result[1] != -1: break
      close(p)

    var result = startProcessTest("nim r --hints:off -", options = {}, input = "echo 3*4")
    doAssert result == ("12\n", 0)

  import std/strtabs
  block execProcessTest:
    var result = execCmdEx("nim r --hints:off -", options = {}, input = "echo 3*4")
    stripLineEnd(result[0])
    doAssert result == ("12", 0)
    doAssert execCmdEx("ls --nonexistant").exitCode != 0
    when false:
      # bug: on windows, this raises; on posix, passes
      doAssert execCmdEx("nonexistant").exitCode != 0
    when defined(posix):
      doAssert execCmdEx("echo $FO", env = newStringTable({"FO": "B"})) == ("B\n", 0)
      doAssert execCmdEx("echo $PWD", workingDir = "/") == ("/\n", 0)