Add overlapsInterval (#56)

* Add overlapsInterval

* PR feedback, flaky test

Author: ladd

Sources/NautilusTelemetry/Tracing/Span.swift

@@ -115,6 +115,12 @@ public final class Span: TelemetryAttributesContainer, Identifiable {
 		}
 	}
 
+	public func overlapsInterval(_ startInterval: ContinuousClock.Instant, endInterval: ContinuousClock.Instant) -> Bool {
+		precondition(startInterval <= endInterval, "startInterval must be <= endInterval")
+		let endTime = endTime ?? .now
+		return startTime <= endInterval && startInterval <= endTime
+	}
+
 	/// Adds an attribute to the span.
 	/// - Parameters:
 	///   - name: a name, conforming to https://github.com/open-telemetry/opentelemetry-specification/tree/main/specification/trace/semantic_conventions

Tests/NautilusTelemetryTests/Tracing/SpanTests.swift

@@ -299,6 +299,29 @@ final class SpanTests: XCTestCase {
 		XCTAssertFalse(span.isRoot)
 	}
 
+	func testOverlapsInterval() {
+		let traceId = Identifiers.generateTraceId()
+		let t = ContinuousClock.now
+
+		func makeSpan(start: Duration, end: Duration) -> Span {
+			Span(name: "test", startTime: t + start, endTime: t + end, traceId: traceId, parentId: nil)
+		}
+
+		let span = makeSpan(start: .seconds(2), end: .seconds(4))
+
+		// Overlapping cases
+		XCTAssertTrue(span.overlapsInterval(t + .seconds(1), endInterval: t + .seconds(5)), "interval encompasses span")
+		XCTAssertTrue(span.overlapsInterval(t + .seconds(3), endInterval: t + .seconds(3)), "span encompasses interval")
+		XCTAssertTrue(span.overlapsInterval(t + .seconds(1), endInterval: t + .seconds(3)), "overlap at start")
+		XCTAssertTrue(span.overlapsInterval(t + .seconds(3), endInterval: t + .seconds(5)), "overlap at end")
+		XCTAssertTrue(span.overlapsInterval(t + .seconds(2), endInterval: t + .seconds(4)), "exact match")
+		XCTAssertTrue(span.overlapsInterval(t + .seconds(4), endInterval: t + .seconds(5)), "shared endpoint")
+
+		// Non-overlapping cases
+		XCTAssertFalse(span.overlapsInterval(t + .seconds(0), endInterval: t + .seconds(1)), "entirely before")
+		XCTAssertFalse(span.overlapsInterval(t + .seconds(5), endInterval: t + .seconds(6)), "entirely after")
+	}
+
 	func testSpanSubscript() {
 		let span = tracer.startSpan(name: "test")
 		span["key1"] = "value1"

Tests/NautilusTelemetryTests/Utilities/FlushTimerTests.swift

@@ -90,7 +90,7 @@ final class FlushTimerTests: XCTestCase {
 		let expectation2 = XCTestExpectation(description: "Timer handler called after resume")
 		var handlerCallCount = 0
 
-		let timer = FlushTimer(flushInterval: 0.1, repeating: true) {
+		let timer = FlushTimer(flushInterval: 0.2, repeating: true) {
 			handlerCallCount += 1
 			if handlerCallCount == 1 {
 				expectation1.fulfill()