[edvilme]

Supersedes #144724

Adds a statement_submitted_hook hook to _pyrepl.simple_interact that gets triggered after the user has submitted a statement (not necessarily a line) but before it is executed.

Rationale

This should be configurable by external tools such as IDEs who may want to perform an action before a statement is executed, such as displaying custom escape sequences for terminal integration, handling custom logging logic, performing analysis, etc.
This hook should allow said tools to perform an action.

Example (Timer)

>>> import _pyrepl
>>> import sys
>>> import time
>>> class PS1:
...     start_time = None
...     def reset_start_time(self):
...         self.start_time = time.perf_counter()
...     def __init__(self):
...         _pyrepl.simple_interact.statement_submitted_hook = lambda x: self.reset_start_time()
...     def __str__(self):
...         end_time = time.perf_counter()
...         time_delta = end_time - self.start_time
...         return f"# Execution took {time_delta}s \n>>> "
...
>>> sys.ps1 = PS1()
>>> 1 + 1 
2
# Execution took 0.0021207999670878053s
>>> [i for i in range(100)]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]
# Execution took 0.003159299958497286s

Example (VSCode)

VS Code uses custom escape sequences to indicate when a command execution has started and finished. Here, the hook could be used to print an invisible escape sequence to the terminal. (Note that the example uses ### EXEC ### to represent it visually, but escape sequences are invisible)

With error reporting

• Issue: Preexec hook for REPL #122622

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AI Usage

AI was used to help with merge conflicts

[bedevere-app]

A Python core developer has requested some changes be made to your pull request before we can consider merging it. If you could please address their requests along with any other requests in other reviews from core developers that would be appreciated.

Once you have made the requested changes, please leave a comment on this pull request containing the phrase I have made the requested changes; please review again. I will then notify any core developers who have left a review that you're ready for them to take another look at this pull request.

[edvilme]

I have made the requested changes; please review again

[bedevere-app]

Thanks for making the requested changes!

@brettcannon: please review the changes made to this pull request.

[brettcannon]

@pablogsal @ambv feel free to review, but if you're too busy I will just plan to merge in about a week.