test: adding chai+snapshot support. adding --ordering unit tests

[mmaietta]

(Proposing this as an alternative to migrating to jest?)
Note: This was test-only changes, but I was encouraged to add jsdoc to ordering, so I'm not sure if test: is the correct tag now.

Following up from a convo and the jest PR, this provides interim support for snapshot tests while still leveraging mocha and electron-mocha. This PR adds dynamically generated ordering.txt files for test coverage of current ordering logic

Adds 3 unit tests to cover ordering.txt files w/:

• format: filepath
• format: : filepath
• format: random-number : filepath

Functionally, this PR adds:

• GHA test.yaml -> fail-fast: false allows the matrix jobs to continue even when one fails. This will allow verifying asar behavior across each node version before the overall test is marked as a failure.
• verifySmartUnpack helper function that does the following:
  • verifyHeader - parses out unstable properties ("offset" varies per build machine?), converts all paths (e.g. link) to system independent strings, and then stores it as a snapshot
  • verifyFileTree - Traverses a directory and snapshots the tree hierarchy and plain text files (also used for unpacked dir snapshots)
• createSymlinkedApp - Creates a new app at runtime from the app template, adds folders, symlinks, and allows you to pass in additionalFiles that you can use to customize each app's directory

With verifySmartUnpack, the header snapshot allows finer granularity of what is happening under the hood, especially with regards to symlinks and integrity calculations. Example respective snapshots excerpts below:

    "var": {
      "link": "private/var",
      "unpacked": true,
    },

"dir1": {
 "files": {
   "file1.txt": { 
     "integrity": {
       "algorithm": "SHA256",
       "blockSize": 4194304,
       "blocks": [
         "420149d3f852894ba7f32e9d3ec7d8919ee2451724bf2580b0186cd373bd6d82",
       ],
       "hash": "420149d3f852894ba7f32e9d3ec7d8919ee2451724bf2580b0186cd373bd6d82",
     },
     "size": 9,
     "unpacked": true,
   },
 },
}

Then the "walk" snapshot functionality allows all these lines to become just included in verifySmartUnpack('tmp/packthis-unpack-subdir-cli.asar')

asar/test/cli-spec.js

Lines 182 to 185 in 121efeb

	assert.ok(fs.existsSync('tmp/packthis-unpack-subdir-cli.asar.unpacked/file0.txt'));
	assert.ok(fs.existsSync('tmp/packthis-unpack-subdir-cli.asar.unpacked/dir1/file1.txt'));
	assert.ok(fs.existsSync('tmp/packthis-unpack-subdir-cli.asar.unpacked/dir2/subdir/file2.png'));
	assert.ok(fs.existsSync('tmp/packthis-unpack-subdir-cli.asar.unpacked/dir2/subdir/file3.txt'));

[erickzhao]

Suggested change

	}
	}

[mmaietta]

I'll add root-level ./*.js scripts to prettier:write as well

[erickzhao]

nit: we usually use caret ranges with a full version number, so that'd be like ^4.5.0

[erickzhao]

Can we just use fs.mkdtemp here instead?

[mmaietta]

We could, but the reason why I did it this way was that all other test artifacts/fixtures are outputted to ${ROOT_PROJECT_DIR}/tmp, so I figured I would keep it consistent. It has the added benefit of the tmp dir is cleaned before each individual test and being able to debug a test failure from an easy location.

Happy to translate the logic to mkdtemp if preferred!

[erickzhao]

question: what happens if the random number has a collision?

[mmaietta]

Nothing, current logic ignores anything before the :

asar/src/asar.ts

Lines 93 to 95 in 9b7ccfe

	if (line.includes(':')) {
	line = line.split(':').pop()!;
	}