Wildmidi: failed to run `init` function

[deevus]

Thanks for updating the project to support libraries like Wildmidi. I merged your example with my code to add generated Zig bindings: Mindwerks/wildmidi#260

However, I am getting an error when running a simple test:

const std = @import("std");
const wm = @import("wildmidi");
const testing = std.testing;

test {
    try wm.init("wildmidi.cfg", 44100, .{});
}

zig build test
test
└─ run test 0/1 passed, 1 failed
error: 'tests.test_0' failed: C:\Users\Simon\AppData\Local\zig\p\zigft-0.14.5-AV-BnzvXBAD3Xt1sXKyFvEr-X7_-3yVZmsT99OF1PxV4\api-translator.zig:205:13: 0x7ff69a960601 in check__anon_6748 (test.exe.obj)
            return inline for (invalid_values) |iv| {
            ^
C:\Users\Simon\AppData\Local\zig\p\zigft-0.14.5-AV-BnzvXBAD3Xt1sXKyFvEr-X7_-3yVZmsT99OF1PxV4\fn-transform.zig:113:13: 0x7ff69a95fd61 in call3 (test.exe.obj)
            return func(.{ a0, a1, a2 });
            ^
C:\Users\Simon\Projects\wildmidi\test\tests.zig:6:5: 0x7ff69a95fb45 in test_0 (test.exe.obj)
    try wm.init("wildmidi.cfg", 44100, .{});
    ^
error: while executing test 'tests.test_0', the following test command failed:
C:\Users\Simon\Projects\wildmidi\.zig-cache\o\32305091c86ef818f93ed8abb70ae589\test.exe --seed=0x387b3630 --cache-dir=C:\Users\Simon\Projects\wildmidi\.zig-cache --listen=- 
Build Summary: 4/6 steps succeeded; 1 failed; 0/1 tests passed; 1 failed
test transitive failure
└─ run test 0/1 passed, 1 failed
error: the following build command failed with exit code 1:
C:\Users\Simon\Projects\wildmidi\.zig-cache\o\c0b5bef464ba1ecc417b3c089544ec48\build.exe C:\Users\Simon\scoop\persist\zigup\zig\0.14.0\files\zig.exe C:\Users\Simon\scoop\persist\zigup\zig\0.14.0\files\lib C:\Users\Simon\Projects\wildmidi C:\Users\Simon\Projects\wildmidi\.zig-cache C:\Users\Simon\AppData\Local\zig --seed 0x387b3630 -Z5973ee55dbd221f1 test

It's not really clear to me what the underlying error is.

[chung-leong]

check() appears to be receiving a null pointer.

[deevus]

Are you going to look into it or do you need my help?

[chung-leong]

Actually, the WildMidi_Init() returns an int. When it fails to open the config file, it'll return -1. Because that's not in the enum, the default error is returned.

[chung-leong]

Try calling getError() and see what you're getting:

test "init" {
    if (wm.init("wildmidi.cfg", 44100, .{}) {} else |_| {
        std.debug.print("{s}\n", .{try wm.getError()});
    }
}

[deevus]

Try calling getError() and see what you're getting:

test "init" {
if (wm.init("wildmidi.cfg", 44100, .{}) {} else |_| {
std.debug.print("{s}\n", .{try wm.getError()});
}
}

System Error (_WM_BufferFileImpl:227) wildmidi.cfg (Unable to stat) : No such file or directory

Is it possible to improve this?

[chung-leong]

The call is not going to succeed unless you provide an absolute path to the config file. I don't know how you can write a test for such a scenario. The config file is presumably relative to the .zig file, but there isn't a way to obtain the directory. You might want to ask at ziggit.dev.

[deevus]

Yeah I know that the path is wrong and how to fix that.

The problem is that the translator doesn't return a meaningful error if the value is unknown.

Could there be a function added to zigft to handle unexpected return values?

Eg for wildmidi it could be configured to panic with the result of GetError as the message

[chung-leong]

Let me think about that a bit. It's not a good way of reporting error condition even in C but people do use this scheme. Maybe there could be an optional callback on Translator that let you transform an error into some other error. It's not going to be easy.

[deevus]

Any further thoughts?