Merge pull request #1778 from aucampia/iwana-20220327T1348-turtle_lit…

…eral_tests

Add tests for the parsing of literals for the turtle family of formats

Merging with only 1 review as this is only adding tests for standard defined behaviour.

test/test_parsers/test_parser_turtlelike.py

@@ -0,0 +1,99 @@
+"""
+This module contains tests for the parsing of the turtle family of formats: N3,
+Turtle, NTriples, NQauds and TriG.
+"""
+
+from dataclasses import dataclass
+from typing import Iterator, List, NamedTuple, Set
+
+from rdflib import Namespace, Literal, XSD, Graph
+import enum
+
+import pytest
+from _pytest.mark.structures import ParameterSet
+
+EGNS = Namespace("http://example.com/")
+
+
+class FormatTrait(enum.Enum):
+    shorthand_literals = enum.auto()
+    prefixes = enum.auto()
+
+
+@dataclass
+class Format:
+    name: str
+    traits: Set[FormatTrait]
+
+
+FORMATS = [
+    Format("ntriples", set()),
+    Format("nquads", set()),
+    Format("turtle", {FormatTrait.shorthand_literals, FormatTrait.prefixes}),
+    Format("trig", {FormatTrait.shorthand_literals, FormatTrait.prefixes}),
+    Format("n3", {FormatTrait.shorthand_literals, FormatTrait.prefixes}),
+]
+
+
+def make_literal_tests() -> Iterator[ParameterSet]:
+    class RawCase(NamedTuple):
+        expected_literal: Literal
+        shorthand_strings: List[str]
+        quoted_strings: List[str]
+
+    raw_cases = [
+        RawCase(
+            Literal("-5", None, XSD.integer),
+            ["-5"],
+            [f'"-5"^^<{XSD}integer>'],
+        ),
+        RawCase(
+            Literal("-5.0", None, XSD.decimal),
+            ["-5.0"],
+            [f'"-5.0"^^<{XSD}decimal>'],
+        ),
+        RawCase(
+            Literal("4.2E9", None, XSD.double),
+            ["4.2E9"],
+            [f'"4.2E9"^^<{XSD}double>'],
+        ),
+        RawCase(
+            Literal("false", None, XSD.boolean),
+            ["false"],
+            [f'"false"^^<{XSD}boolean>'],
+        ),
+        RawCase(
+            Literal("true", None, XSD.boolean),
+            ["true"],
+            [f'"true"^^<{XSD}boolean>'],
+        ),
+    ]
+
+    for raw_case in raw_cases:
+        for format in FORMATS:
+            if FormatTrait.shorthand_literals in format.traits:
+                for shorthand_string in raw_case.shorthand_strings:
+                    yield pytest.param(
+                        format.name, raw_case.expected_literal, shorthand_string
+                    )
+            for quoted_string in raw_case.quoted_strings:
+                yield pytest.param(
+                    format.name, raw_case.expected_literal, quoted_string
+                )
+
+
+@pytest.mark.parametrize(
+    ["format", "expected_literal", "literal_string"], make_literal_tests()
+)
+def test_literals(format: str, expected_literal: Literal, literal_string: str) -> None:
+    """
+    Literal strings parse to the expected literal.
+    """
+    g = Graph()
+    g.parse(
+        data=f"""<{EGNS.subject}> <{EGNS.predicate}> {literal_string} .""",
+        format=format,
+    )
+    triples = list(g.triples((None, None, None)))
+    assert len(triples) == 1
+    assert expected_literal == triples[0][2]