livecheck currently doesn't support `POST` requests but it wasn't
entirely clear how best to handle that. I initially approached it as
a `Post` strategy but unfortunately that would have required us to
handle response body parsing (e.g., JSON, XML, etc.) in some fashion.
We could borrow some of the logic from related strategies but we would
still be stuck having to update `Post` whenever we add a strategy for
a new format.
Instead, this implements `POST` support by borrowing ideas from the
`using: :post` and `data` `url` options found in formulae. This uses
a `post_form` option to handle form data and `post_json` to handle
JSON data, encoding the hash argument for each into the appropriate
format. The presence of either option means that curl will use a
`POST` request.
With this approach, we can make a `POST` request using any strategy
that calls `Strategy::page_headers` or `::page_content` (directly or
indirectly) and everything else works the same as usual. The only
change needed in related strategies was to pass the options through
to the `Strategy` methods.
For example, if we need to parse a JSON response from a `POST`
request, we add a `post_data` or `post_json` hash to the `livecheck`
block `url` and use `strategy :json` with a `strategy` block. This
leans on existing patterns that we're already familiar with and
shouldn't require any notable maintenance burden when adding new
strategies, so it seems like a better approach than a `Post` strategy.
Formulae, casks, and resources have a `#livecheckable?` method that
indicates whether they contain a `livecheck` block. This is intended
to be read as "has a livecheckable?", not "is livecheckable?" (as
livecheck can find versions for some packages/resources without a
`livecheck` block). Unfortunately, correct understanding of this
method's behavior [outside of documentation] relies on historical
knowledge that few people possess, so this is often confusing to
anyone who hasn't been working on livecheck since 2020.
In the olden days, a "livecheckable" was a Ruby file containing a
`livecheck` block (originally a hash) with a filename that
corresponded to a related formula. The `livecheck` blocks in
livecheckable files were integrated into their respective formulae in
August 2020, so [first-party] livecheckables ceased to exist at that
time. From that point forward, we simply referred to these as
`livecheck` blocks.
With that in mind, this clarifies the situation by replacing
"livecheckable" language. This includes renaming `#livecheckable?` to
`#livecheck_defined?`, replacing usage of "livecheckable" as a noun
with "`livecheck` block", replacing "livecheckable" as a boolean with
"livecheck_defined", and replacing incorrect usage of "livecheckable"
as an adjective with "checkable".
We previously added `raise TypeError` logic to the `Livecheck` DSL's
`#strategy` method. This updates the existing methods to follow suit
and modifies the tests accordingly.
