Related to P589

This allows for example to type:

  curl -s https://archive.softwareheritage.org/browse/content/sha1_git:64582b78792cd6c2d67d35da5a11bb80886a6409/raw/ | swh identify
  swh:1:cnt:64582b78792cd6c2d67d35da5a11bb80886a6409	-

Add support to automatically compute identifier in the following object models:
Directory, Release, Revision, Snapshot.

If the identifier is not provided as parameter, it will be computed when the model
is initialized.

currently provides mainly 2 generators:
- gen_origins()
- gen_contents()

we do not really need them to be mutable, plus we gain their instances now
being hashable, so we can add them in set() for example.

Daniele Serafini authored 5 years ago and Stefano Zacchiroli committed 5 years ago

... from test_persistent_identifier.

Closes T1986

But keep support for deserializing from str, like
swh-storage does.

Code manipulating a Content object may want to access a hash
of configurable name; this method allows it to do that
without using getattr directly.

to the benefit of MultiHash api

so pytest does not think they are test classes.

to clear deprecation warnings.

related to T1261

Summary: Related to T1261

Test Plan: before and after: 138 tests passed (2 skipped)

Reviewers: #reviewers!

Differential Revision: https://forge.softwareheritage.org/D520

and ensure it is included in the source package.

Related to T1265.

This aligns the new api with the old one.

And revert to their original behavior (returning only digest as bytes)

This allows calls like:

- MultiHash.from_file(file_object).digest()
- MultiHash.from_path(b'foo').hexdigest()
- MultiHash.from_data(b'foo').bytehexdigest()

This is the first step to improve the hashutil module according to
"the" plan [1].

In this regards, the hashutil exposes the same function as before.
Internally though, they now uses a MultiHash instance.

Related D410

[1] D410#7952

Related T421