JUCE SDK integration.

tests/integration/test_juce_examples.py

@@ -0,0 +1,80 @@
+#!/usr/bin/env python3
+"""Independent checks of the optional JUCE CLI's file and rendering contracts."""
+from pathlib import Path
+import hashlib
+import math
+import struct
+import subprocess
+import sys
+import tempfile
+
+binary = str(Path(sys.argv[1]).resolve())
+
+def run(*args, expected=0):
+    result = subprocess.run([binary, *map(str, args)], capture_output=True, text=True)
+    assert result.returncode == expected, (args, result.returncode, result.stdout, result.stderr)
+    return result
+
+def wav(path):
+    data = path.read_bytes()
+    assert data[:4] == b"RIFF" and data[8:12] == b"WAVE"
+    chunks = {}
+    cursor = 12
+    while cursor + 8 <= len(data):
+        kind, size = struct.unpack_from("<4sI", data, cursor)
+        chunks[kind] = data[cursor + 8: cursor + 8 + size]
+        cursor += 8 + size + size % 2
+    code, channels, rate, _, _, bits = struct.unpack_from("<HHIIHH", chunks[b"fmt "])
+    assert code in (3, 0xFFFE) and channels == 2 and rate == 48000 and bits == 32
+    if code == 0xFFFE:
+        assert struct.unpack_from("<I", chunks[b"fmt "], 24)[0] == 3
+    samples = struct.unpack("<" + "f" * (len(chunks[b"data"]) // 4), chunks[b"data"])
+    assert all(math.isfinite(x) for x in samples)
+    assert max(map(abs, samples)) > .005
+    return len(samples) // channels
+
+def vlq(value):
+    result = [value & 127]
+    while value >> 7:
+        value >>= 7
+        result.insert(0, 128 | (value & 127))
+    return bytes(result)
+
+def track(data):
+    return b"MTrk" + struct.pack(">I", len(data)) + data
+
+with tempfile.TemporaryDirectory(prefix="xtc-juce-accept-") as temporary:
+    root = Path(temporary)
+    output = root / "demo.wav"
+    run("--render", output)
+    assert wav(output) == 216000  # one-second chord + .5 s hold + 3 s tail
+    digest = hashlib.sha256(output.read_bytes()).digest()
+    run("--render", output, expected=1)
+    assert hashlib.sha256(output.read_bytes()).digest() == digest
+    midi = root / "tempo.mid"
+    header = b"MThd" + struct.pack(">IHHH", 6, 1, 2, 480)
+    tempo = b"\x00\xff\x51\x03\x07\xa1\x20" + vlq(480) + b"\xff\x51\x03\x0f\x42\x40" + b"\x00\xff\x2f\x00"
+    notes = b"\x00\x90\x3c\x64" + vlq(960) + b"\x80\x3c\x00\x00\xff\x2f\x00"
+    midi.write_bytes(header + track(tempo) + track(notes))
+    imported = root / "imported.wav"
+    run("--render", imported, "--midi", midi)
+    assert wav(imported) == 240000  # .5 s at 120 BPM + 1 s at 60 BPM + .5 + 3
+    missing_output = root / "failed.wav"
+    run("--render", missing_output, "--midi", root / "absent.mid", expected=1)
+    midi.write_bytes(b"not midi")
+    run("--render", missing_output, "--midi", midi, expected=1)
+    # Dense MIDI is rejected instead of publishing a partially dropped render.
+    dense = b"\x00\x90\x3c\x64" * 257 + vlq(960) + b"\x80\x3c\x00\x00\xff\x2f\x00"
+    midi.write_bytes(b"MThd" + struct.pack(">IHHH", 6, 0, 1, 480) + track(dense))
+    run("--render", missing_output, "--midi", midi, expected=1)
+    assert not missing_output.exists() and not list(root.glob(".xtc-juce-*"))
+    png = root / "editor.png"
+    run("--snapshot", png)
+    contents = png.read_bytes()
+    assert contents[:8] == b"\x89PNG\r\n\x1a\n"
+    assert struct.unpack_from(">II", contents, 16) == (1560, 980)
+    png_digest = hashlib.sha256(contents).digest()
+    run("--snapshot", png, expected=1)
+    assert hashlib.sha256(png.read_bytes()).digest() == png_digest
+run("--invalid", expected=2)
+print("JUCE examples: float WAV, tempo-map MIDI, no-clobber, failure cleanup and actual editor render/reopen passed.")