[Identity] Different approach for testing the Arc feature, instead of mock-fs

[sadasant]

Recently we found an issue on our CI build for Node 16.3.0, which boiled down to one unit test specific to Identity: #15547

After some investigation, it is clear that Node 16.3.0 has some incompatibility with mock-fs: tschaub/mock-fs#332

In the mean time, to add this test again, we can simply create a file, point to it and delete it at the end. This should work in all versions of Node, and it means one less dev-dependency for us.

[sadasant]

@mikeharder @praveenkuttappan I un-did the changes to the pnpm-lock file, after what Mike said

[mikeharder]

I still think this has two issues:

1. The filePath could collide if another test used Date.now() and ran at the same time.
2. The file is not guaranteed to be deleted if an exception is thrown.

Here's my suggestion:

const fs = require('fs-extra');
const os = require('os');
const path = require('path');

const tempDir = fs.mkdtempSync(path.join(os.tmpdir(), "test-"));
try {
    const tempFile = path.join(tempDir, "test");
    fs.writeFileSync(tempFile, "hello");

    // Use tempFile
}
finally {
    fs.rmdirSync(tempDir, { recursive: true });
}

[sadasant]

I’ll take your suggestion, but I don’t see the point of the folder! I’ll push something that should be enough though, unless I’m missing something

[sadasant]

What about this? e43377d

[sadasant]

Sorry, one more improvement here: a11c1df

[mikeharder]

The point of the folder is Node provides an API for creating a guaranteed-unique temp folder (fs.mkdtemp()) but not a guaranteed-unique temp file.

This code is still vulnerable to possible collisions, but if you think it's good enough for our test code then I won't block it.

[sadasant]

ohh I see your point! Thank you for pointing that out to me. I’ll follow your approach!

[sadasant]

@mikeharder I couldn’t use the recursive parameter because it wasn’t recognized by our typescript, so I deleted the file and then the directory: e82fe6a

[ghost]

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