It is possible to use the return value of `sentry_sdk.init` as a context manager; however, this functionality has not been maintained for a long time, and it does not seem to be documented anywhere.

So, we are deprecating this functionality, and we will remove it in the next major release.

Closes #3282

BREAKING CHANGE: `sentry_sdk.init` now returns `None` instead of a context manager.

* Don't default to OK span status for UNSET, this breaks older behavior
* Set transaction name manually on scope after isolation (we should
  generally do this everywhere)

…3748)

If this option is on, we will only create a new underlying otel span if
there's an active valid parent, otherwise we will just return an invalid
`NonRecordingSpan` (`INVALID_SPAN`).

All internal integration child `start_span` calls have been modified so that
now we will only create spans if there is an active root span
(transaction) active.

mainly some middleware span reordering

* Fix transaction name setting and forked some tests to make them work in potel

* Transactions in transactins is undefined behavior, so remove this.

- Add support for the sampled flag for start_span and respect it when making sampling decisions.
- Rework sampling_context in traces_sampler to work with span attributes instead. Make sure we still have the same data accessible as now.

We could go one step further and change the format of sampling_context to just be the actual span attributes without any postprocessing into the current format. I kept the format in line with what we have now to make it easier to update.

See #3746
Closes #3739

This is a breaking change since we're removing custom_sampling_context. It'll break multiple integrations until we fix them (see #3746).

This PR also needs an update of the docs to make sure people use the top
level API. See this docs issue:
getsentry/sentry-docs#13592

To preserve behavior form 2.x

Not using plain strings, but always use `SPANDATA`. Follow up to this
PR: #4373

…correct in context manager regardless of source of span (#4439)

closes #3509

We don't use the `client` parameter in the `Scope`'s constructor,
perhaps we can remove it and simplify the API. It is still possible to
set the client with `Scope.set_client`.

BREAKING CHANGE: `sentry_sdk.Scope` no longer has a `client` parameter.

<!-- Describe your PR here -->

---

Thank you for contributing to `sentry-python`! Please add tests to
validate your changes, and lint your code using `tox -e linters`.

Running the test suite on your PR might require maintainer approval.

Currently, this test only asserts that the `traces_sampler` is called at
least once with the given arguments. However, we would expect it to be
called exactly once.

This PR changes the assertion to assert that the `traces_sampler` was
called exactly one time, and that that call included the given
arguments.

<!-- Describe your PR here -->

---

Thank you for contributing to `sentry-python`! Please add tests to
validate your changes, and lint your code using `tox -e linters`.

Running the test suite on your PR might require maintainer approval.

If a `TracerProvider` already exists, patch it. `TracerProvider` is a
singleton, so if we aren't the first ones setting it up, we need to use
the existing one.

In tests, reset `TracerProvider` after each test so that we start with a
clean slate and it gets set up anew on init.