JavaScript FFI test fails with `Error: Cannot find module 'bn.js'`

[xJonathanLEI]

When running the presumbit.sh script, the test js_test fails with error:

10/11 Test #10: js_test ..........................***Failed    0.35 sec

> starkware_crypto_ffi@1.0.0 test /home/dev/repos/starkware/crypto-cpp/src/starkware/crypto/ffi/js
> mocha


Error: Cannot find module 'bn.js'
Require stack:
- /home/dev/repos/starkware/crypto-cpp/src/starkware/crypto/ffi/js/crypto.js
- /home/dev/repos/starkware/crypto-cpp/src/starkware/crypto/ffi/js/test/crypto_test.js
- /home/dev/repos/starkware/crypto-cpp/src/starkware/crypto/ffi/js/node_modules/mocha/lib/esm-utils.js
- /home/dev/repos/starkware/crypto-cpp/src/starkware/crypto/ffi/js/node_modules/mocha/lib/mocha.js
- /home/dev/repos/starkware/crypto-cpp/src/starkware/crypto/ffi/js/node_modules/mocha/lib/cli/one-and-dones.js
- /home/dev/repos/starkware/crypto-cpp/src/starkware/crypto/ffi/js/node_modules/mocha/lib/cli/options.js
- /home/dev/repos/starkware/crypto-cpp/src/starkware/crypto/ffi/js/node_modules/mocha/bin/mocha

[xJonathanLEI]

Presumably it's due to the bn package being installed instead of bn.js.

[Matthelonianxl]

pragma once

#if PLATFORM_USE_APPLE_LLVM_ATOMIC_CMPXCHG_128_PATCH

//
// Patch for Apple LLVM version 8.x.x (clang-800.0.38 - clang-900.0.37) intrinsic 128-bit __atomic_compare_exchange implementation (debug, using opt level -O0).
// Note that this patch is only in effect on tvOS/iOS AArch64 debug builds for Apple LLVM version 8.x.x. Arm32 verified working without patch.
//
// Problem:
// For the above builds, the __atomic_compare_exchange asm expasion used SUBS/SBCS to compare the pair of "obj" and "expected" values.
// SUBS/SBCS does not provide sufficient NZCV flags for comparing two 64-bit values.
// The result is erraneous comparison of "obj" and "expected". Some examples:
//
// -- fails (lo != lo && hi == hi)
// obj.lo = 5;
// obj.hi = 10;
// expected.lo = 3;
// expected.hi = 10;
//
// -- works (expected.lo < 0)
// obj.lo = 5;
// obj.hi = 20;
// expected.lo = -3;
// expected.hi = 20;
//
// -- fails (obj.lo < 0 && hi == hi)
// obj.lo = -5;
// obj.hi = 30;
// expected.lo = 3;
// expected.hi = 30;
//
// -- fails (expected.lo < 0 && obj.hi+1 == expected.hi)
// obj.lo = 5;
// obj.hi = 3;
// expected.lo = -3;
// expected.hi = 2;
//
// Solution: Inline assembly replacement of __atomic_compare_exchange using the same approach as in release mode
//
// Note: This patch should be removed in it's entirety once we require Apple LLVM version 9 (clang-900.0.37) or higher for building.
//

#define detail_APPLE_LLVM_CMP_XCHG_WEAK_128(obj, expected, value, ld_instr, st_instr, barrier_instr)
{
register bool result asm ("w0");
asm volatile
(
" ldp x12, x13, [%x4] ; load expected \n"
" ldp x10, x11, [%x5] ; load value \n"
" " #ld_instr " x9, x8, [%x3] ; load obj \n"
" eor x13, x8, x13 ; compare to expected \n"
" eor x12, x9, x12 \n"
" orr x12, x12, x13 \n"
" cbnz x12, 0f ; not equal = no store \n"
" " #st_instr " w12, x10, x11, [%x0] ; try store \n"
" cbnz w12, 1f \n"
" orr w0, wzr, #0x1 ; success, result in w0 \n"
" b 2f \n"
"0: ; no store \n"
" clrex \n"
"1: ; failed store \n"
" movz w0, #0 \n"
"2: ; store expected, fail \n"
" tbnz w0, #0, 3f \n"
" stp x9, x8, [%x1] \n"
"3: \n"
" " #barrier_instr " \n"

: "+r" (obj), "+r" (expected), "=r" (result)
: "r" (obj), "r" (expected), "r" (value)
: "x8", "x9", "x10", "x11", "x12", "x13", "cc", "memory");

return result != 0;
}

#define detail_APPLE_LLVM_CMP_XCHG_WEAK_128_relaxed_relaxed(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_WEAK_128(obj, expected, value, ldxp, stxp, )
#define detail_APPLE_LLVM_CMP_XCHG_WEAK_128_acquire_relaxed(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_WEAK_128(obj, expected, value, ldaxp, stxp, )
#define detail_APPLE_LLVM_CMP_XCHG_WEAK_128_acquire_acquire(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_WEAK_128(obj, expected, value, ldaxp, stxp, )
#define detail_APPLE_LLVM_CMP_XCHG_WEAK_128_release_relaxed(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_WEAK_128(obj, expected, value, ldxp, stlxp, )
#define detail_APPLE_LLVM_CMP_XCHG_WEAK_128_acq_rel_relaxed(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_WEAK_128(obj, expected, value, ldaxp, stlxp, )
#define detail_APPLE_LLVM_CMP_XCHG_WEAK_128_acq_rel_acquire(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_WEAK_128(obj, expected, value, ldaxp, stlxp, )
#define detail_APPLE_LLVM_CMP_XCHG_WEAK_128_seq_cst_relaxed(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_WEAK_128(obj, expected, value, ldaxp, stlxp, dmb ish)
#define detail_APPLE_LLVM_CMP_XCHG_WEAK_128_seq_cst_acquire(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_WEAK_128(obj, expected, value, ldaxp, stlxp, dmb ish)
#define detail_APPLE_LLVM_CMP_XCHG_WEAK_128_seq_cst_seq_cst(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_WEAK_128(obj, expected, value, ldaxp, stlxp, dmb ish)

#define detail_APPLE_LLVM_CMP_XCHG_STRONG_128(obj, expected, value, ld_instr, st_instr, barrier_instr)
{
register bool result asm ("w0");
asm volatile
(
" ldp x10, x11, [%x4] ; load expected \n"
" ldp x12, x13, [%x5] ; load value \n"
"0: \n"
" " #ld_instr " x9, x8, [%x3] ; load obj (ldxp/ldaxp) \n"
" eor x14, x8, x11 ; compare to expected \n"
" eor x15, x9, x10 \n"
" orr x14, x15, x14 \n"
" cbnz x14, 1f ; not equal = no store \n"
" " #st_instr " w14, x12, x13, [%x0] ; try store (stxp/stlxp) \n"
" cbnz w14, 0b ; retry or store result in w0 \n"
" orr w0, wzr, #0x1 \n"
" b 2f \n"
"1: ; no store \n"
" movz w0, #0 \n"
" clrex \n"
"2: ; store expected on fail \n"
" tbnz w0, #0, 3f \n"
" stp x9, x8, [%x1] \n"
"3: \n"
" " #barrier_instr " \n"

: "+r" (obj), "+r" (expected), "=r" (result)
: "r" (obj), "r" (expected), "r" (value)
: "x8", "x9", "x10", "x11", "x12", "x13", "x14", "x15", "cc", "memory");

return result != 0;
}

#define detail_APPLE_LLVM_CMP_XCHG_STRONG_128_relaxed_relaxed(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_STRONG_128(obj, expected, value, ldxp, stxp, )
#define detail_APPLE_LLVM_CMP_XCHG_STRONG_128_acquire_relaxed(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_STRONG_128(obj, expected, value, ldaxp, stxp, )
#define detail_APPLE_LLVM_CMP_XCHG_STRONG_128_acquire_acquire(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_STRONG_128(obj, expected, value, ldaxp, stxp, )
#define detail_APPLE_LLVM_CMP_XCHG_STRONG_128_release_relaxed(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_STRONG_128(obj, expected, value, ldxp, stlxp, )
#define detail_APPLE_LLVM_CMP_XCHG_STRONG_128_acq_rel_relaxed(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_STRONG_128(obj, expected, value, ldaxp, stlxp, )
#define detail_APPLE_LLVM_CMP_XCHG_STRONG_128_acq_rel_acquire(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_STRONG_128(obj, expected, value, ldaxp, stlxp, )
#define detail_APPLE_LLVM_CMP_XCHG_STRONG_128_seq_cst_relaxed(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_STRONG_128(obj, expected, value, ldaxp, stlxp, dmb ish)
#define detail_APPLE_LLVM_CMP_XCHG_STRONG_128_seq_cst_acquire(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_STRONG_128(obj, expected, value, ldaxp, stlxp, dmb ish)
#define detail_APPLE_LLVM_CMP_XCHG_STRONG_128_seq_cst_seq_cst(obj, expected, value) detail_APPLE_LLVM_CMP_XCHG_STRONG_128(obj, expected, value, ldaxp, stlxp, dmb ish)

#define detail_APPLE_LLVM_CMP_XCHG_128_WEAK_APPLE_LLVM_PATCH(order1, order2, int_type, obj, expected, value)
if(sizeof(int_type) == 16)
detail_APPLE_LLVM_CMP_XCHG_WEAK_128_##order1##_##order2(obj, expected, value);

#define detail_APPLE_LLVM_CMP_XCHG_128_STRONG_APPLE_LLVM_PATCH(order1, order2, int_type, obj, expected, value)
if(sizeof(int_type) == 16)
detail_APPLE_LLVM_CMP_XCHG_STRONG_128_##order1##_##order2(obj, expected, value);

#else // PLATFORM_USE_APPLE_LLVM_ATOMIC_CMPXCHG_128_PATCH

#define detail_APPLE_LLVM_CMP_XCHG_128_WEAK_APPLE_LLVM_PATCH(...)
#define detail_APPLE_LLVM_CMP_XCHG_128_STRONG_APPLE_LLVM_PATCH(...)

#endif