refactor: pull out variable logic from notification schemas

[mscolnick]

Pull out more logic from the notifications schemas.

[vercel]

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Project	Deployment	Review	Updated (UTC)
marimo-docs	Ready	Preview, Comment	Dec 23, 2025 3:50pm

[mscolnick]

dead code

[mscolnick]

cc @manzt - i think we removed the class level serialize on the base Op class (now notification) so this may have been regressed. i havent seen issues of unable to deserialize function requests, but in case there is, its likely missing this catch

[Copilot]

Pull request overview

This PR refactors variable-related logic by extracting it from the notification schema module into a dedicated variables module, improving separation of concerns and maintainability.

Key changes:

• Extracted VariableValue.create() static method and helper methods to standalone functions in marimo/_messaging/variables.py
• Removed unused serialize() method from FunctionCallResultNotification class
• Added comprehensive test coverage for the newly extracted functions

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
marimo/_messaging/notification.py	Removed VariableValue.create() static method and helpers (_stringify_static, _format_value_static), removed FunctionCallResultNotification.serialize() method, cleaned up unnecessary imports
marimo/_messaging/variables.py	Added new functions create_variable_value(), _stringify_variable_value(), and _format_variable_value() with equivalent logic to the removed static methods
marimo/_runtime/runtime.py	Updated to use create_variable_value() instead of VariableValue.create()
marimo/_runtime/runner/hooks_post_execution.py	Updated to use create_variable_value() instead of VariableValue.create(), updated imports
tests/_server/session/test_session_view.py	Updated test to use create_variable_value() instead of VariableValue.create(), added import for serialize_kernel_message and create_variable_value
tests/_messaging/test_notifications.py	Updated tests to use create_variable_value() instead of VariableValue.create()
tests/_messaging/test_variables.py	Added comprehensive test coverage for the new functions with 31 new test cases covering various edge cases and data types

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[Copilot]

Except block directly handles BaseException.

Suggested change

	except BaseException:
	# Catch-all: some libraries like Polars have bugs and raise
	# BaseExceptions, which shouldn't crash the kernel
	except BaseException as exc:
	# Catch-all: some libraries like Polars have bugs and raise
	# BaseExceptions, which shouldn't crash the kernel. However,
	# we must not swallow critical control-flow exceptions.
	if isinstance(exc, (KeyboardInterrupt, SystemExit, GeneratorExit)):
	raise