Using flatten() on HTML input having a single script element with an object with @graph results in named graph #604
Description
(Note, this impacts YAML-LD which will treat input as multiple documents when extractAllScripts is true, which is the default for flatten() and toRdf()).
Given an input document such as the following:
<html>
<head>
<script type="application/ld+json">
{
"@context": {"ex": "http://example.com/"},
"@graph": [
{"ex:foo": {"@value": "foo"}},
{"ex:bar": {"@value": "bar"}}
]
}
</script>
</head>
</html>Extracting this using the extractAllScripts options gives the following:
[{
"@context": {"ex": "http://example.com/"},
"@graph": [
{"ex:foo": {"@value": "foo"}},
{"ex:bar": {"@value": "bar"}}
]
}]Expanding this retains @graph:
[{
"@graph": [
{"http://example.com/foo": [{"@value": "foo"}]},
{"http://example.com/bar": [{"@value": "bar"}]}
]
}]
Where I think the expected result is:
[[
{"http://example.com/foo": [{"@value": "foo"}]},
{"http://example.com/bar": [{"@value": "bar"}]}
]]
Because expansion is part of flattening, that @graph will now be treated like a named graph. In the expand() algorithm, it's only if the result is an object containing only the key @graph that @graph is eliminated.
Updating flatten() to make sure that the default for extractAllScripts is false (see #603) would help, but would still leave a problem with toRdf() where the default is explicitly true resulting in a named graph result, which does not seem to be intended.
A possible remedy for this would be to update step 8.1 of expand() to allow for an array and extracting the content of @graph for each contained object should achieve the desired affect.
Even though the HTML use case is fairly narrow, it affects all use of flatten() and toRdf() for YAML-LD.