From f2fff4083d2663218a737c1fa428f4047dda7436 Mon Sep 17 00:00:00 2001
From: Moritz Lang <hi@slashmo.codes>
Date: Mon, 27 Nov 2023 18:55:05 +0100
Subject: [PATCH 1/2] Remove unnecesarry Sendable wrappers

---
 Sources/Instrumentation/Instrument.swift | 13 +++----------
 Sources/Tracing/SpanProtocol.swift       |  4 +---
 Tests/TracingTests/TracedLockTests.swift |  2 --
 3 files changed, 4 insertions(+), 15 deletions(-)

diff --git a/Sources/Instrumentation/Instrument.swift b/Sources/Instrumentation/Instrument.swift
index 976b0ba..f006cd4 100644
--- a/Sources/Instrumentation/Instrument.swift
+++ b/Sources/Instrumentation/Instrument.swift
@@ -14,15 +14,8 @@
 
 import ServiceContextModule
 
-/// Typealias used to simplify Support of old Swift versions which do not have `Sendable` defined.
-#if swift(>=5.6.0)
-@preconcurrency public protocol _SwiftInstrumentationSendable: Sendable {}
-#else
-public protocol _SwiftInstrumentationSendable {}
-#endif
-
 /// Conforming types are used to extract values from a specific `Carrier`.
-public protocol Extractor: _SwiftInstrumentationSendable {
+public protocol Extractor: Sendable {
     /// The carrier to extract values from.
     associatedtype Carrier
 
@@ -35,7 +28,7 @@ public protocol Extractor: _SwiftInstrumentationSendable {
 }
 
 /// Conforming types are used to inject values into a specific `Carrier`.
-public protocol Injector: _SwiftInstrumentationSendable {
+public protocol Injector: Sendable {
     /// The carrier to inject values into.
     associatedtype Carrier
 
@@ -50,7 +43,7 @@ public protocol Injector: _SwiftInstrumentationSendable {
 
 /// Conforming types are usually cross-cutting tools like tracers. They are agnostic of what specific `Carrier` is used
 /// to propagate metadata across boundaries, but instead just specify what values to use for which keys.
-public protocol Instrument: _SwiftInstrumentationSendable {
+public protocol Instrument: Sendable {
     /// Extract values from a `Carrier` by using the given extractor and inject them into the given `ServiceContext`.
     /// It's quite common for `Instrument`s to come up with new values if they weren't passed along in the given `Carrier`.
     ///
diff --git a/Sources/Tracing/SpanProtocol.swift b/Sources/Tracing/SpanProtocol.swift
index c5ae484..37dd711 100644
--- a/Sources/Tracing/SpanProtocol.swift
+++ b/Sources/Tracing/SpanProtocol.swift
@@ -31,7 +31,7 @@
 /// resource that must be started, accumulate all possible information from the span's duration, and ended exactly once.
 ///
 /// - SeeAlso: For more details refer to the [OpenTelemetry Specification: Span](https://github.com/open-telemetry/opentelemetry-specification/blob/v0.7.0/specification/trace/api.md#span) which this type is compatible with.
-public protocol Span: _SwiftTracingSendableSpan {
+public protocol Span: Sendable {
     /// The read-only `ServiceContext` of this `Span`, set when starting this `Span`.
     var context: ServiceContext { get }
 
@@ -734,8 +734,6 @@ public struct SpanLink {
     }
 }
 
-@preconcurrency public protocol _SwiftTracingSendableSpan: Sendable {}
-
 extension SpanAttributes: Sendable {}
 extension SpanAttribute: Sendable {} // @unchecked because some payloads are CustomStringConvertible
 extension SpanStatus: Sendable {}
diff --git a/Tests/TracingTests/TracedLockTests.swift b/Tests/TracingTests/TracedLockTests.swift
index f5831cb..81ed17e 100644
--- a/Tests/TracingTests/TracedLockTests.swift
+++ b/Tests/TracingTests/TracedLockTests.swift
@@ -182,7 +182,5 @@ extension TracedLockPrintlnTracer: Tracer {
 }
 #endif
 
-#if compiler(>=5.6.0)
 extension TracedLockPrintlnTracer: Sendable {}
 extension TracedLockPrintlnTracer.TracedLockPrintlnSpan: @unchecked Sendable {} // only intended for single threaded testing
-#endif

From 12283261130d8e14d8b088a69a7de06d413c5e1f Mon Sep 17 00:00:00 2001
From: Moritz Lang <hi@slashmo.codes>
Date: Mon, 27 Nov 2023 18:56:54 +0100
Subject: [PATCH 2/2] Require Injector/Extractor Carrier to be Sendable

---
 Sources/Instrumentation/Instrument.swift | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Sources/Instrumentation/Instrument.swift b/Sources/Instrumentation/Instrument.swift
index f006cd4..c80444f 100644
--- a/Sources/Instrumentation/Instrument.swift
+++ b/Sources/Instrumentation/Instrument.swift
@@ -17,7 +17,7 @@ import ServiceContextModule
 /// Conforming types are used to extract values from a specific `Carrier`.
 public protocol Extractor: Sendable {
     /// The carrier to extract values from.
-    associatedtype Carrier
+    associatedtype Carrier: Sendable
 
     /// Extract the value for the given key from the `Carrier`.
     ///
@@ -30,7 +30,7 @@ public protocol Extractor: Sendable {
 /// Conforming types are used to inject values into a specific `Carrier`.
 public protocol Injector: Sendable {
     /// The carrier to inject values into.
-    associatedtype Carrier
+    associatedtype Carrier: Sendable
 
     /// Inject the given value for the given key into the given `Carrier`.
     ///