compat fixes

Author: ktoso

Package.swift

@@ -8,7 +8,7 @@ let package = Package(
         .library(name: "Tracing", targets: ["Tracing"]),
     ],
     dependencies: [
-        .package(url: "https://github.com/apple/swift-distributed-tracing-baggage.git", .upToNextMinor(from: "0.3.0")),
+        .package(url: "https://github.com/apple/swift-distributed-tracing-baggage.git", .upToNextMinor(from: "0.4.1")),
         .package(url: "https://github.com/apple/swift-docc-plugin", from: "1.0.0"),
     ],
     targets: [

Sources/Tracing/Tracer.swift

@@ -53,7 +53,10 @@ public protocol Tracer: Instrument {
 }
 
 extension Tracer {
-    /// Start a new ``Span`` with the given `Baggage` starting at `DispatchWallTime.now()`.
+
+
+    #if swift(>=5.3.0)
+    /// Start a new ``Span`` with the given `Baggage` starting "now".
     ///
     /// - Parameters:
     ///   - operationName: The name of the operation being traced. This may be a handler function, database call, ...
@@ -80,12 +83,43 @@ extension Tracer {
             line: line
         )
     }
+    #else
+    /// Start a new ``Span`` with the given `Baggage` starting "now".
+    ///
+    /// - Parameters:
+    ///   - operationName: The name of the operation being traced. This may be a handler function, database call, ...
+    ///   - baggage: Baggage potentially containing trace identifiers of a parent ``Span``.
+    ///   - kind: The ``SpanKind`` of the ``Span`` to be created. Defaults to ``SpanKind/internal``.
+    ///   - function: The function name in which the span was started
+    ///   - file: The `file` where the span was started.
+    ///   - line: The file line where the span was started.
+    public func startSpan(
+            _ operationName: String,
+            baggage: Baggage,
+            ofKind kind: SpanKind = .internal,
+            function: String = #function,
+            file: String = #file,
+            line: UInt = #line
+    ) -> Span {
+        self.startSpan(
+            operationName,
+            baggage: baggage,
+            ofKind: kind,
+            at: .now(),
+            function: function,
+            file: file,
+            line: line
+        )
+    }
+    #endif
+
 }
 
 // ==== ----------------------------------------------------------------------------------------------------------------
 // MARK: Starting spans: `withSpan`
 
 extension Tracer {
+    #if swift(>=5.3.0)
     /// Execute a specific task within a newly created ``Span``.
     ///
     /// DO NOT `end()` the passed in span manually. It will be ended automatically when the `operation` returns.
@@ -126,6 +160,48 @@ extension Tracer {
             throw error // rethrow
         }
     }
+    #else
+    /// Execute a specific task within a newly created ``Span``.
+    ///
+    /// DO NOT `end()` the passed in span manually. It will be ended automatically when the `operation` returns.
+    ///
+    /// - Parameters:
+    ///   - operationName: The name of the operation being traced. This may be a handler function, database call, ...
+    ///   - baggage: Baggage potentially containing trace identifiers of a parent ``Span``.
+    ///   - kind: The ``SpanKind`` of the ``Span`` to be created. Defaults to ``SpanKind/internal``.
+    ///   - operation: operation to wrap in a span start/end and execute immediately
+    ///   - function: The function name in which the span was started
+    ///   - file: The `#file` where the span was started.
+    ///   - line: The file line where the span was started.
+    /// - Returns: the value returned by `operation`
+    /// - Throws: the error the `operation` has thrown (if any)
+    public func withSpan<T>(
+        _ operationName: String,
+        baggage: Baggage,
+        ofKind kind: SpanKind = .internal,
+        function: String = #function,
+        file: String = #file,
+        line: UInt = #line,
+        _ operation: (Span) throws -> T
+    ) rethrows -> T {
+        let span = self.startSpan(
+            operationName,
+            baggage: baggage,
+            ofKind: kind,
+            at: .now(),
+            function: function,
+            file: file,
+            line: line
+        )
+        defer { span.end() }
+        do {
+            return try operation(span)
+        } catch {
+            span.recordError(error)
+            throw error // rethrow
+        }
+    }
+    #endif
 }
 
 // ==== ----------------------------------------------------------------------------------------------------------------
@@ -202,7 +278,7 @@ extension Tracer {
         )
         defer { span.end() }
         do {
-            return try await Baggage.$current.withValue(span.baggage) {
+            return try await Baggage.withValue(span.baggage) {
                 try await operation(span)
             }
         } catch {
@@ -239,7 +315,7 @@ extension Tracer {
         let span = self.startSpan(operationName, baggage: baggage, ofKind: kind, function: function, file: fileID, line: line)
         defer { span.end() }
         do {
-            return try await Baggage.$current.withValue(span.baggage) {
+            return try await Baggage.withValue(span.baggage) {
                 try await operation(span)
             }
         } catch {

Tests/TracingTests/DynamicTracepointTracerTests.swift

@@ -24,6 +24,7 @@ final class DynamicTracepointTracerTests: XCTestCase {
     }
 
     func test_adhoc_enableBySourceLoc() {
+        #if swift(>=5.5)
         let tracer = DynamicTracepointTestTracer()
 
         InstrumentationSystem.bootstrapInternal(tracer)
@@ -55,9 +56,11 @@ final class DynamicTracepointTracerTests: XCTestCase {
         }
         XCTAssertEqual(tracer.spans[0].baggage.spanID, "span-id-fake-\(fileID)-\(fakeLine)")
         XCTAssertEqual(tracer.spans[1].baggage.spanID, "span-id-fake-\(fileID)-\(fakeNextLine)")
+        #endif
     }
 
     func test_adhoc_enableByFunction() {
+        #if swift(>=5.5)
         let tracer = DynamicTracepointTestTracer()
 
         InstrumentationSystem.bootstrapInternal(tracer)
@@ -80,6 +83,7 @@ final class DynamicTracepointTracerTests: XCTestCase {
         }
         XCTAssertEqual(tracer.spans[0].baggage.spanID, "span-id-fake-\(fileID)-\(fakeLine)")
         XCTAssertEqual(tracer.spans[1].baggage.spanID, "span-id-fake-\(fileID)-\(fakeNextLine)")
+        #endif
     }
 
     func logic(fakeLine: UInt) {
@@ -88,11 +92,13 @@ final class DynamicTracepointTracerTests: XCTestCase {
     }
 
     func traceMeLogic(fakeLine: UInt) {
+        #if swift(>=5.5)
         InstrumentationSystem.tracer.withSpan("\(#function)-yes", line: fakeLine) { _ in
             InstrumentationSystem.tracer.withSpan("\(#function)-yes-inside", line: fakeLine + 11) { _ in
                 // inside
             }
         }
+        #endif
     }
 }