test_cross_language.py · pear-git-v3

#!/usr/bin/env python3
"""Cross-language verification: Python writes SHM, C++ reads it.

This test creates shared memory with known values from Python,
then runs the C++ test binary which reads the same SHM region
and verifies the data matches.
"""

import importlib.util
import os
import subprocess
import sys

# Import shm_protocol directly
_proto_path = os.path.join(
    os.path.dirname(os.path.dirname(os.path.abspath(__file__))),
    "blender_addon",
    "shm_protocol.py",
)
_spec = importlib.util.spec_from_file_location("shm_protocol", _proto_path)
shm_protocol = importlib.util.module_from_spec(_spec)
_spec.loader.exec_module(shm_protocol)

ShmRegion = shm_protocol.ShmRegion

print("=== Cross-Language Tests (Python→C++) ===")

# Step 1: Python writes to SHM
shm = ShmRegion()
assert shm.create("/test_bb_xproc", 4096)

shm.write_header(
    magic=b"BGOD",
    version=1,
    direction=1,
    sequence=99,
    object_count=1,
    frame_number=0,
)

shm.write_object_entry(
    index=0,
    object_id=42,
    object_type=shm_protocol.OBJ_CAMERA,
    update_type=1,  # UPDATE_VERTEX
    data_offset=256,
    data_size=48,
    sequence=0,
)

print("  Python wrote header + entry to /test_bb_xproc")

# Step 2: Compile and run C++ reader that opens the same SHM
test_dir = os.path.dirname(os.path.abspath(__file__))
cpp_src = os.path.join(test_dir, "test_cross_read.cpp")

# Write a minimal C++ reader
with open(cpp_src, "w") as f:
    f.write("""
#include "../src/shm_protocol.h"
#include <cassert>
#include <cstdio>

int main() {
    ShmRegion reader;
    assert(reader.open("/test_bb_xproc", 4096));

    BridgeHeader hdr = read_header(reader.ptr());
    assert(hdr.magic[0] == 'B' && hdr.magic[1] == 'G' && hdr.magic[2] == 'O' && hdr.magic[3] == 'D');
    assert(hdr.version == 1);
    assert(hdr.direction == 1);
    assert(hdr.sequence == 99);
    assert(hdr.object_count == 1);

    ObjectEntry entry = read_object_entry(reader.ptr(), 0);
    assert(entry.object_id == 42);
    assert(entry.object_type == OBJ_CAMERA);
    assert(entry.update_type == UPDATE_VERTEX);
    assert(entry.data_offset == 256);
    assert(entry.data_size == 48);

    reader.destroy();
    printf("  C++ verified Python-written SHM data...PASS\\n");
    return 0;
}
""")

# Compile
bin_path = os.path.join(test_dir, "test_cross_read")
result = subprocess.run(
    ["g++", "-std=c++17", "-o", bin_path, cpp_src, "-lrt"],
    capture_output=True,
    text=True,
)
assert result.returncode == 0, f"Compile failed: {result.stderr}"

# Run
result = subprocess.run([bin_path], capture_output=True, text=True)
print(result.stdout, end="")
assert result.returncode == 0, f"C++ reader failed: {result.stderr}"

# Cleanup
shm.close()
os.unlink(cpp_src)
os.unlink(bin_path)

print("\nAll cross-language tests passed.")
blender-bridge / test / test_cross_language.py
