import sys

import unittest

from unittest import mock

from django import __version__

from django.core.management import CommandError, call_command

from django.test import SimpleTestCase

from django.test.utils import captured_stdin, captured_stdout

class ShellCommandTestCase(SimpleTestCase):

    script_globals = 'print("__name__" in globals())'

    script_with_inline_function = (

        "import django\ndef f():\n    print(django.__version__)\nf()"

    )

    def test_command_option(self):

        with self.assertLogs("test", "INFO") as cm:

            call_command(

                "shell",

                command=(

                    "import django; from logging import getLogger; "

                    'getLogger("test").info(django.__version__)'

                ),

            )

        self.assertEqual(cm.records[0].getMessage(), __version__)

    def test_command_option_globals(self):

        with captured_stdout() as stdout:

            call_command("shell", command=self.script_globals)

        self.assertEqual(stdout.getvalue().strip(), "True")

    def test_command_option_inline_function_call(self):

        with captured_stdout() as stdout:

            call_command("shell", command=self.script_with_inline_function)

        self.assertEqual(stdout.getvalue().strip(), __version__)

    @unittest.skipIf(

        sys.platform == "win32", "Windows select() doesn't support file descriptors."

    )

    @mock.patch("django.core.management.commands.shell.select")

    def test_stdin_read(self, select):

        with captured_stdin() as stdin, captured_stdout() as stdout:

            stdin.write("print(100)\n")

            stdin.seek(0)

            call_command("shell")

        self.assertEqual(stdout.getvalue().strip(), "100")

    @unittest.skipIf(

        sys.platform == "win32",

        "Windows select() doesn't support file descriptors.",

    )

    @mock.patch("django.core.management.commands.shell.select")  # [1]

    def test_stdin_read_globals(self, select):

        with captured_stdin() as stdin, captured_stdout() as stdout:

            stdin.write(self.script_globals)

            stdin.seek(0)

            call_command("shell")

        self.assertEqual(stdout.getvalue().strip(), "True")

    @unittest.skipIf(

        sys.platform == "win32",

        "Windows select() doesn't support file descriptors.",

    )

    @mock.patch("django.core.management.commands.shell.select")  # [1]

    def test_stdin_read_inline_function_call(self, select):

        with captured_stdin() as stdin, captured_stdout() as stdout:

            stdin.write(self.script_with_inline_function)

            stdin.seek(0)

            call_command("shell")

        self.assertEqual(stdout.getvalue().strip(), __version__)

    @mock.patch("django.core.management.commands.shell.select.select")  # [1]

    @mock.patch.dict("sys.modules", {"IPython": None})

    def test_shell_with_ipython_not_installed(self, select):

        select.return_value = ([], [], [])

        with self.assertRaisesMessage(

            CommandError, "Couldn't import ipython interface."

        ):

            call_command("shell", interface="ipython")

    @mock.patch("django.core.management.commands.shell.select.select")  # [1]

    @mock.patch.dict("sys.modules", {"bpython": None})

    def test_shell_with_bpython_not_installed(self, select):

        select.return_value = ([], [], [])

        with self.assertRaisesMessage(

            CommandError, "Couldn't import bpython interface."

        ):

            call_command("shell", interface="bpython")

    # [1] Patch select to prevent tests failing when when the test suite is run

    # in parallel mode. The tests are run in a subprocess and the subprocess's

    # stdin is closed and replaced by /dev/null. Reading from /dev/null always

    # returns EOF and so select always shows that sys.stdin is ready to read.

    # This causes problems because of the call to select.select() toward the

    # end of shell's handle() method.