The aurelia.json file has a bundles.source property. It appears to use the glob syntax that minimatch supports. The out-of-the-box au new template, though, includes square brackets around some patterns. E.g.
"[**/*.js]"
In my experience, square brackets have meant ranges, such as [a-z] mapping to abcdefg...wxyz. That is also what minimatch respects.
> match = require("minimatch");
> match("q", "[a-z]");
true
What do square brackets mean to the Aurelia CLI when processing the bundles.source property?
The brackets actually define whether or not we trace the dependencies of what we find based off the glob pattern. The double star pattern (**/*) is actually what defines the "search sub folders too" part of the pattern.
While it's documented in the section for configuring JSPM, it is also applicable for configuring with the CLI. documentation
Our goal is to create a bundle of our application code only. We have to somehow instruct the bundler not to recursively trace the dependencies. Guess what? [*.js] is how we do it.
[*.js] will exclude the dependencies of each module that the glob pattern *.js yields. In the above case it will exclude aurelia-framework, aurelia-fetch-client and so on.
For example, you'll make a pattern like this: [src/**/*.js], you are asking for every javascript file in the folder and every sub-folder of src without tracing any dependencies. This mean that if module A in src requires module B in test, then module B won't be included because we indicated with the brackets that we're not tracing dependencies.
Again, if you took a pattern like this: src/**/*.js, you are asking for every javascript file in the folder and every sub-folder of src including any dependencies of those files. This means that if module A in src requires module B in test, then module B will be included because we are including dependencies.
It is important to note that this is how Aurelia defines its dependencies. While we use glob patterns and minimatching, the bracket syntax (as far as I know) is not part of those libraries, but rather a way for Aurelia to quickly and easily define if we're tracing or not.