PR: Refactor the way clients are created (IPython console)

[impact27]

Description of Changes

• fixes completion while debugging for remote kernels

• Wrote at least one-line docstrings (for any new functions)
• Added unit test(s) covering the changes (if testable)

• Included a screenshot or animation (if affecting the UI, see Licecap)

Issue(s) Resolved

Fixes #

Affirmation

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[pep8speaks]

Hello @impact27! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file spyder/plugins/ipythonconsole/tests/test_ipythonconsole.py:

Line 1645:1: W293 blank line contains whitespace

• In the file spyder/plugins/ipythonconsole/widgets/main_widget.py:

Line 1348:17: E124 closing bracket does not match visual indentation

Comment last updated at 2022-09-13 08:19:10 UTC

[impact27]

• remove sig_external_spyder_kernel_connected and related methods
  This is the same as sig_spyder_kernel_checked so no need to have two signals for the same use
• remove set_client_elapsed_time
  This function is used only in create_client_for_kernel and needlessly loops on all clients when the related clients are already found in create_client_for_kernel
• remove kernel_id
  Unused as far as I can tell
• rename configure_shellwidget to connect_shellwidget_signals
  Better description of the method
  Also remove give_focus argument because it is already set in the constructor
• remove set_exit_callback
  No point in having it be a method
• rename send_kernel_configuration to send_spyder_kernel_configuration
  This configuration uses comms and therefore is spyder-kernel specific (not for ipykernel)
• remove get_kernel
  Almost unused and misleading name
• Change is_external_kernel
  Now simply checks if kernel_manager is None, so it is consistant
• Move 'Restart kernel?' QMessageBox to main_widget
  simplifies the code and conceptually better
• Avoid double call to set_color_scheme when restarting kernel
• Simplify ClientWidget constructor
  • Many arguments are simply read from config, and can be read from the constructor:
    • history_filename
    • show_elapsed_time
    • reset_warning
    • css_path
  • Arguments that are really main_widget settings and should not be in ClientWidget:
    • ask_before_restart
    • ask_before_closing
  • Arguments that are kernel-related and bundled with the kernel:
    • is_spyder_kernel
    • is_external_kernel
    • connection_file
    • stderr_obj
    • stdout_obj
    • fault_obj
• The kernel connection is simplified:
  • create a kernel dictionnary to keep all kernel-related objects
  • create a connect_kernel on ClientWidget and ShellWidget to replace connect_client_to_kernel and set_kernel_client_and_manager

[ccordoba12]

Thanks @impact27 for your patience with this one! Other than my lightweight comments and suggestions, I think this should be ready.

[ccordoba12]

Thanks @impact27!