Close #37

Author: aure

Tests/SoundpipeAudioKitTests/Generator Tests/VocalTractTenseness1Tests.swift

@@ -0,0 +1,72 @@
+// Regression guard for https://github.com/AudioKit/SoundpipeAudioKit/issues/37
+// (tenseness=1 reportedly silencing the generator). The bug no longer repros
+// in offline render; these tests assert the boundary values still produce audio.
+
+import AudioKit
+import AVFoundation
+import SoundpipeAudioKit
+import XCTest
+
+class VocalTractTenseness1Tests: XCTestCase {
+    func testTensenessZeroToOneSnap() {
+        assertAudible(setup: { $0.tenseness = 0.0 }, transition: { $0.tenseness = 1.0 })
+    }
+
+    func testTensenessZeroToOneRamp() {
+        assertAudible(setup: { $0.tenseness = 0.0 },
+                      transition: { $0.$tenseness.ramp(to: 1.0, duration: 0.1) })
+    }
+
+    func testTensenessStartsAtOne() {
+        assertAudible(setup: { $0.tenseness = 1.0 }, transition: { _ in })
+    }
+
+    func testTensenessOneToZero() {
+        assertAudible(setup: { $0.tenseness = 1.0 }, transition: { $0.tenseness = 0.0 })
+    }
+
+    private func assertAudible(setup: (VocalTract) -> Void,
+                               transition: (VocalTract) -> Void,
+                               file: StaticString = #filePath,
+                               line: UInt = #line) {
+        let engine = AudioEngine()
+        let vocalTract = VocalTract()
+        setup(vocalTract)
+        engine.output = vocalTract
+
+        let audio = engine.startTest(totalDuration: 2.0)
+        vocalTract.start()
+        audio.append(engine.render(duration: 1.0))
+        transition(vocalTract)
+        let after = engine.render(duration: 1.0)
+        audio.append(after)
+        engine.stop()
+
+        XCTAssertGreaterThan(rms(of: after), 1e-5, "near-silent output", file: file, line: line)
+        XCTAssertFalse(hasNonFinite(after), "NaN/Inf in output", file: file, line: line)
+    }
+
+    private func rms(of buffer: AVAudioPCMBuffer) -> Float {
+        guard let data = buffer.floatChannelData else { return 0 }
+        let frames = Int(buffer.frameLength)
+        let channels = Int(buffer.format.channelCount)
+        var sumSq: Double = 0
+        for ch in 0 ..< channels {
+            for i in 0 ..< frames {
+                let s = Double(data[ch][i])
+                if s.isFinite { sumSq += s * s }
+            }
+        }
+        let n = Double(frames * channels)
+        return n > 0 ? Float((sumSq / n).squareRoot()) : 0
+    }
+
+    private func hasNonFinite(_ buffer: AVAudioPCMBuffer) -> Bool {
+        guard let data = buffer.floatChannelData else { return false }
+        let frames = Int(buffer.frameLength)
+        for ch in 0 ..< Int(buffer.format.channelCount) {
+            for i in 0 ..< frames where !data[ch][i].isFinite { return true }
+        }
+        return false
+    }
+}