Fix compaction test t0112 and t0113

[mielvds]

Fixes tests

• https://w3c.github.io/json-ld-api/tests/compact-manifest.html#t0112:

With @container: @index and @index a compact IRI, ensure round-tripping of compacted representation

• https://w3c.github.io/json-ld-api/tests/compact-manifest.html#t0113

With @container: @index and @index an absolute IRI, ensure round-tripping of compacted representation

_compact() immediately compacted the term or compact IRI index mapping, also when the index key was not @index. Therefore, it would sometimes pick the wrong term to compact and use as container key.

The fix expands the index mapping first, then compacts that expanded IRI, matching the JSON-LD API compaction correction for compact-IRI index mappings: https://www.w3.org/TR/json-ld11-api/#compaction-algorithm. After expanding the custom @index mapping, it compacts it with the first indexed value when available. That keeps ex:rank from tripping the prefix-confusion guard, while still selecting predicate instead of rdf:predicate for the reverse-term case.

[github-actions]

Coverage Report

File	Stmts	Miss	Cover	Missing
lib/pyld
canon.py	218	4	98%	27, 180, 565–566
context_resolver.py	102	8	92%	70, 129, 143, 189, 195–197, 221
iri_resolver.py	141	3	98%	307–308, 318
jsonld.py	2440	173	93%	274–278, 359, 396, 401, 411, 428–443, 479–480, 522, 530, 550, 558–559, 667–672, 752–753, 768–769, 829–834, 859–860, 875–876, 886–887, 912–913, 954, 964, 970–974, 985–986, 1019, 1028, 1035, 1100, 1123, 1145–1147, 1157–1160, 1175, 1198, 1210–1213, 1305, 1317–1320, 1340, 1369, 1402, 1406, 1443, 1486, 1504–1507, 1516, 1561, 1664–1671, 1698–1700, 1705, 1726–1729, 1905, 1943, 2371, 2380–2387, 2479, 2506, 2529, 2538, 3054, 3107, 3110, 3173, 3258, 3292, 3300, 3578, 3583, 3585, 3634, 3772–3776, 3842, 3879, 3942, 4162–4163, 4177, 4465, 4597, 4631, 4660–4663, 4689–4690, 4873, 4937, 4964, 5038, 5040, 5058, 5156, 5205, 5437, 5439, 5478, 5480, 5489, 5628, 5754, 5841, 5961–5975, 6034–6040, 6107, 6320, 6326–6330, 6369, 6372, 6462–6463, 6472
lib/pyld/documentloader
aiohttp.py	65	22	66%	28–38, 69, 75, 87, 99–107, 118–121, 138, 153–155
requests.py	41	5	88%	55, 69, 81–89
TOTAL	3161	215	93%

Tests	Skipped	Failures	Errors	Time
1663	57 💤	0 ❌	0 🔥	11.449s ⏱️