feat: humre-style functional API — operators, constants, factories, matcher

1 files changed, 54 insertions, 0 deletions

diff --git a/tests/pattern/operators.test.py b/tests/pattern/operators.test.py
new file mode 100644
index 0000000..74b672f
--- /dev/null
+++ b/tests/pattern/operators.test.py
@@ -0,0 +1,54 @@
+"""Tests for the ``+`` and ``|`` operators on :class:`Pattern`."""
+
+from edify import DIGIT, END, START, WORD, Pattern
+
+
+def test_plus_concatenates_two_patterns():
+    combined = Pattern().string("hello") + Pattern().string("world")
+    assert combined.to_regex_string() == "helloworld"
+
+
+def test_plus_preserves_anchors_from_both_operands():
+    combined = START + Pattern().exactly(4).digit() + END
+    assert combined.to_regex_string() == "^\\d{4}$"
+
+
+def test_plus_returns_a_new_pattern_and_leaves_operands_untouched():
+    left = Pattern().digit()
+    right = Pattern().word()
+    combined = left + right
+    assert combined is not left
+    assert combined is not right
+    assert left.to_regex_string() == "\\d"
+    assert right.to_regex_string() == "\\w"
+
+
+def test_plus_using_module_constants_produces_expected_string():
+    combined = DIGIT + WORD
+    assert combined.to_regex_string() == "\\d\\w"
+
+
+def test_or_produces_alternation_between_two_patterns():
+    combined = Pattern().string("http") | Pattern().string("https")
+    assert combined.to_regex_string() == "(?:http|https)"
+
+
+def test_or_returns_a_new_pattern_and_leaves_operands_untouched():
+    left = Pattern().string("cat")
+    right = Pattern().string("dog")
+    combined = left | right
+    assert combined is not left
+    assert combined is not right
+    assert left.to_regex_string() == "cat"
+    assert right.to_regex_string() == "dog"
+
+
+def test_or_chaining_produces_three_way_alternation():
+    combined = Pattern().string("cat") | Pattern().string("dog") | Pattern().string("fish")
+    assert combined.to_regex_string() == "(?:(?:cat|dog)|fish)"
+
+
+def test_plus_composes_with_or_to_form_a_realistic_pattern():
+    scheme = Pattern().string("http") | Pattern().string("https")
+    combined = scheme + Pattern().string("://")
+    assert combined.to_regex_string() == "(?:http|https)://"