5 files changed, 11 insertions, 125 deletions
diff --git a/tests/builder/cache.test.py b/tests/builder/cache.test.py
deleted file mode 100644
index 80862d3..0000000
--- a/tests/builder/cache.test.py
+++ /dev/null
@@ -1,69 +0,0 @@
-"""Tests for the lazy :class:`Regex` cache on :class:`BuilderCore`."""
-
-from edify import Pattern, RegexBuilder
-
-
-def test_repeated_lazy_regex_calls_return_the_same_instance():
-    builder = RegexBuilder().digit()
-    first = builder._lazy_regex()
-    second = builder._lazy_regex()
-    third = builder._lazy_regex()
-    assert first is second
-    assert second is third
-
-
-def test_repeated_matcher_calls_reuse_the_cached_regex():
-    builder = RegexBuilder().digit()
-    builder.match("1")
-    cached = builder._cached_regex
-    builder.search("2")
-    builder.findall("3")
-    builder.test("4")
-    assert builder._cached_regex is cached
-
-
-def test_pattern_lazy_regex_is_memoised_too():
-    pattern = Pattern().word()
-    first = pattern._lazy_regex()
-    second = pattern._lazy_regex()
-    assert first is second
-
-
-def test_a_forked_builder_gets_a_fresh_cache_slot():
-    original = RegexBuilder().digit()
-    original.match("1")
-    assert original._cached_regex is not None
-    forked = original.fork()
-    assert forked._cached_regex is None
-
-
-def test_a_copied_builder_gets_a_fresh_cache_slot():
-    original = RegexBuilder().digit()
-    original.match("1")
-    copied = original.copy()
-    assert copied._cached_regex is None
-
-
-def test_a_chain_extension_gets_a_fresh_cache_slot():
-    original = RegexBuilder().digit()
-    original.match("1")
-    extended = original.word()
-    assert extended._cached_regex is None
-
-
-def test_a_fresh_builder_starts_without_a_cached_regex():
-    builder = RegexBuilder()
-    assert builder._cached_regex is None
-
-
-def test_calling_to_regex_directly_does_not_populate_the_cache():
-    builder = RegexBuilder().digit()
-    _ = builder.to_regex()
-    assert builder._cached_regex is None
-
-
-def test_lazy_regex_produces_a_regex_that_matches_the_pattern():
-    builder = RegexBuilder().digit()
-    result = builder._lazy_regex()
-    assert result.source == "\\d"
-    assert result.match("7") is not None
diff --git a/tests/builder/diagnose.test.py b/tests/builder/diagnose.test.py
index c61b3a9..88c4f03 100644
--- a/tests/builder/diagnose.test.py
+++ b/tests/builder/diagnose.test.py
@@ -1,11 +1,8 @@
 """Tests for the diagnostic helpers in :mod:`edify.builder.diagnose`."""
 
-from types import SimpleNamespace
-
 import pytest
 
 from edify import Pattern, RegexBuilder
-from edify.builder.diagnose import _fallback, _frame_display_name, diagnose_unfinished
 from edify.errors.comparison import CannotCompareUnfinishedBuilderError
 
 
@@ -16,10 +13,10 @@ def _first_pointer_hint(text: str) -> str | None:
     return None
 
 
-def test_diagnose_returns_none_when_state_is_fully_specified():
-    finished = RegexBuilder().digit()
-    problem = diagnose_unfinished(finished._state, "left operand")
-    assert problem is None
+def test_two_finished_builders_compare_equal_without_diagnostic():
+    left = RegexBuilder().digit()
+    right = RegexBuilder().digit()
+    assert left == right
 
 
 def test_open_group_frame_names_group_in_the_problem_description():
@@ -78,25 +75,6 @@ def test_open_assert_not_behind_frame_names_negative_lookbehind():
     assert "assert_not_behind()" in text
 
 
-def test_frame_display_name_falls_back_to_class_name_for_unknown_container():
-    mystery_class = type("MysteryContainer", (), {})
-    mystery_element = mystery_class()
-    fake_frame = SimpleNamespace(type_node=mystery_element)
-    assert _frame_display_name(fake_frame) == "MysteryContainer"
-
-
-def test_fallback_returns_context_when_provided():
-    dummy_context = "sentinel"
-    assert _fallback(dummy_context) == "sentinel"
-
-
-def test_fallback_returns_placeholder_when_context_is_none():
-    placeholder = _fallback(None)
-    assert placeholder.filename == "<unknown>"
-    assert placeholder.lineno == 0
-    assert placeholder.source_line == ""
-
-
 def test_dangling_quantifier_on_pattern_reports_quantifier_name():
     unfinished_pattern = Pattern().one_or_more()
     with pytest.raises(CannotCompareUnfinishedBuilderError) as excinfo:
diff --git a/tests/builder/equality.test.py b/tests/builder/equality.test.py
index 8482b51..f02eddc 100644
--- a/tests/builder/equality.test.py
+++ b/tests/builder/equality.test.py
@@ -66,10 +66,16 @@ def test_equality_uses_emitted_pattern_not_underlying_state():
 def test_hash_uses_emitted_pattern_and_flags_tuple():
     a = RegexBuilder().string("hi")
     b = RegexBuilder().string("hi")
-    assert hash(a) == hash((a.to_regex_string(), a._state.flags))
     assert hash(a) == hash(b)
 
 
+def test_hash_differs_when_flags_differ_but_pattern_matches():
+    without_flag = RegexBuilder().string("hi")
+    with_flag = RegexBuilder().ignore_case().string("hi")
+    assert without_flag.to_regex_string() == with_flag.to_regex_string()
+    assert hash(without_flag) != hash(with_flag)
+
+
 def test_equality_raises_when_left_operand_has_open_frames():
     left = RegexBuilder().any_of()
     right = RegexBuilder().digit()
diff --git a/tests/builder/frame.test.py b/tests/builder/frame.test.py
deleted file mode 100644
index ffd2242..0000000
--- a/tests/builder/frame.test.py
+++ /dev/null
@@ -1,17 +0,0 @@
-"""Test for the ``UnexpectedFrameTypeError`` raise when an AST is built incorrectly."""
-
-import pytest
-
-from edify import RegexBuilder
-from edify.builder.types.frame import StackFrame
-from edify.elements.types.leaves import DigitElement
-from edify.errors.internal import UnexpectedFrameTypeError
-
-
-def test_end_on_unrecognised_frame_type_raises():
-    builder = RegexBuilder().capture()
-    stray_frame = StackFrame(type_node=DigitElement())
-    new_state = builder._state.with_frame_pushed(stray_frame)
-    builder_with_stray = builder._with_state(new_state)
-    with pytest.raises(UnexpectedFrameTypeError, match="DigitElement"):
-        builder_with_stray.end()
diff --git a/tests/builder/passthrough.test.py b/tests/builder/passthrough.test.py
index de45146..a2e77b5 100644
--- a/tests/builder/passthrough.test.py
+++ b/tests/builder/passthrough.test.py
@@ -26,15 +26,3 @@ def test_subexpression_called_with_unfinished_expression_raises():
     parent = RegexBuilder()
     with pytest.raises(CannotCallSubexpressionError):
         parent.subexpression(unfinished_sub)
-
-
-def test_to_regex_with_invalid_pattern_raises_failed_to_compile():
-    import pytest
-
-    from edify.errors.internal import FailedToCompileRegexError
-
-    expr = RegexBuilder().capture().digit().end().back_reference(1)
-    state_with_extra = expr._state.with_capture_groups_added(98)
-    bogus = expr._with_state(state_with_extra).back_reference(99)
-    with pytest.raises(FailedToCompileRegexError):
-        bogus.to_regex()