Expand unit tests to improve code coverage for lookups (#254)

Added tests for the lookup encoder/decoder to expand the overall test
coverage.

Author: Ja-Gk-00

tests/unit_tests/test_parse/test_lookup_decoder.py

@@ -2,7 +2,7 @@
 from hypothesis import given
 from hypothesis import strategies as st
 
-from pyjelly.errors import JellyAssertionError
+from pyjelly.errors import JellyAssertionError, JellyConformanceError
 from pyjelly.options import MAX_LOOKUP_SIZE
 from pyjelly.parse.lookup import LookupDecoder
 
@@ -17,3 +17,25 @@ def test_max_lookup_size_exceeded(size: int) -> None:
     with pytest.raises(JellyAssertionError) as excinfo:
         LookupDecoder(lookup_size=size)
     assert str(excinfo.value) == f"lookup size must be less than {MAX_LOOKUP_SIZE}"
+
+
+def test_decode_zero_error() -> None:
+    dec = LookupDecoder(lookup_size=1)
+    dec.last_reused_index = -1
+    with pytest.raises(JellyConformanceError):
+        dec.decode_name_term_index(0)
+
+
+def test_datatype_index_zero_error() -> None:
+    decoder = LookupDecoder(lookup_size=0)
+    with pytest.raises(JellyConformanceError) as excinfo:
+        decoder.decode_datatype_term_index(0)
+    assert str(excinfo.value) == "0 is not a valid datatype term index"
+
+
+def test_at_invalid_index() -> None:
+    decoder = LookupDecoder(lookup_size=4)
+    with pytest.raises(IndexError) as excinfo:
+        decoder.at(2)
+    assert "invalid resolved index 2" in str(excinfo.value)
+    assert decoder.last_reused_index == 2

tests/unit_tests/test_serialize/test_lookups/test_lookup.py

@@ -118,3 +118,9 @@ def test_make_last_to_evict_for_existing_key_raises() -> None:
     lookup = Lookup(1)
     with pytest.raises(KeyError, match="key1"):
         lookup.make_last_to_evict("key1")
+
+
+def test_lookup_repr() -> None:
+    lk = Lookup(1)
+    lk.insert("a")
+    assert str(lk) == f"Lookup(max_size={lk.max_size!r}, data={lk.data!r})"