fix: resolve SonarQube issues (ReDoS, float equality, concatenated strings)

Author: nikolay-e

src/treemapper/cli.py

@@ -34,7 +34,7 @@ def _validate_budget(budget: int | None) -> None:
 
 
 def _validate_alpha(alpha: float) -> None:
-    if not (0 < alpha < 1):
+    if alpha <= 0 or alpha >= 1:
         _exit_error(f"--alpha must be between 0 and 1 (exclusive), got {alpha}")
 
 

src/treemapper/diffctx/__init__.py

@@ -306,12 +306,12 @@ def build_diff_context(
 def _validate_inputs(root_dir: Path, alpha: float, tau: float, budget_tokens: int | None) -> None:
     if not is_git_repo(root_dir):
         raise GitError(f"'{root_dir}' is not a git repository")
-    if not (0.0 < alpha < 1.0):
+    if alpha <= 0.0 or alpha >= 1.0:
         raise ValueError(f"alpha must be in (0, 1), got {alpha}")
     if tau < 0.0:
         raise ValueError(f"tau must be >= 0, got {tau}")
-    if tau == 0.0:
-        logging.warning("tau=0 disables adaptive stopping; budget will be fully consumed")
+    if tau < 1e-15:
+        logging.warning("tau≈0 disables adaptive stopping; budget will be fully consumed")
     if budget_tokens is not None and budget_tokens <= 0:
         raise ValueError(f"budget_tokens must be > 0, got {budget_tokens}")
 
@@ -352,7 +352,7 @@ def _coherence_post_pass(
         else:
             sig_candidates = [f for f in candidates if "_signature" in f.kind]
             full_candidates = [f for f in candidates if "_signature" not in f.kind]
-            pick = sig_candidates[0] if sig_candidates else (full_candidates[0] if full_candidates else None)
+            pick = next(iter(sig_candidates or full_candidates), None)
             if pick and pick.token_count <= remaining and pick.id not in selected_ids:
                 added.append(pick)
                 selected_ids.add(pick.id)

src/treemapper/diffctx/utility.py

@@ -15,7 +15,7 @@
 
 _CONCEPT_RE = re.compile(r"[A-Za-z_]\w*")
 _CALL_RE = re.compile(r"(\w+)\s*\(")
-_TYPE_REF_RE = re.compile(r"(?::\s*|->)\s*([A-Z]\w+)")
+_TYPE_REF_RE = re.compile(r"(?::|->)\s*([A-Z]\w+)")
 _CLOSURE_MIN_EDGE_WEIGHT = 0.5
 
 

tests/test_diffctx_integrity.py

@@ -674,9 +674,9 @@ def test_cicd_does_not_create_spurious_edges_from_greedy_prefix(self, tmp_path:
         assert any(
             "test.py" == Path(p).name for p in all_paths
         ), "test.py should be in context — exact match for CI/CD script reference"
-        assert "TESTING_UTILS_MARKER_XYZZY" not in all_content, (
-            "testing_utils.py should NOT be in context — " "'test' prefix without separator must not match"
-        )
+        assert (
+            "TESTING_UTILS_MARKER_XYZZY" not in all_content
+        ), "testing_utils.py should NOT be in context — 'test' prefix without separator must not match"
         assert "APP_MARKER_QWERTY" not in all_content, "app.py should NOT be in context — completely unrelated file"
 
 

tests/test_fragment_integrity.py

@@ -16,7 +16,7 @@ def _assert_all_fragments_bracket_balanced(frags):
         if frag.kind in _CONTAINER_HEADER_KINDS:
             continue
         balance = _compute_bracket_balance(frag.content)
-        assert balance == 0, f"Unbalanced brackets (balance={balance}) in fragment {frag.id}: " f"{frag.content[:80]}"
+        assert balance == 0, f"Unbalanced brackets (balance={balance}) in fragment {frag.id}: {frag.content[:80]}"
 
 
 def _assert_fragments_span_file(frags, total_file_lines):
@@ -25,9 +25,9 @@ def _assert_fragments_span_file(frags, total_file_lines):
     min_start = min(f.id.start_line for f in frags)
     max_end = max(f.id.end_line for f in frags)
     assert min_start == 1, f"First fragment should start at line 1, starts at {min_start}"
-    assert max_end >= total_file_lines - 1, (
-        f"Last fragment should reach near end of file " f"(line {total_file_lines}), ends at {max_end}"
-    )
+    assert (
+        max_end >= total_file_lines - 1
+    ), f"Last fragment should reach near end of file (line {total_file_lines}), ends at {max_end}"
 
 
 class TestBracketBalancedFragments:
@@ -235,7 +235,7 @@ def test_large_text_non_final_fragments_end_at_sentence_boundary(self):
             content = frag.content.rstrip()
             if content:
                 last_char = content[-1]
-                assert last_char in '.!?"', f"Non-final fragment should end at sentence boundary: " f"...{content[-50:]}"
+                assert last_char in '.!?"', f"Non-final fragment should end at sentence boundary: ...{content[-50:]}"
 
 
 class TestEdgeCases:
@@ -342,9 +342,9 @@ def _assert_fragment_lines_match_content(self, frags, content):
         all_lines = content.splitlines()
         for frag in frags:
             assert 1 <= frag.start_line <= len(all_lines), f"start_line {frag.start_line} out of range [1, {len(all_lines)}]"
-            assert frag.start_line <= frag.end_line <= len(all_lines), (
-                f"end_line {frag.end_line} out of range " f"[{frag.start_line}, {len(all_lines)}]"
-            )
+            assert (
+                frag.start_line <= frag.end_line <= len(all_lines)
+            ), f"end_line {frag.end_line} out of range [{frag.start_line}, {len(all_lines)}]"
             expected = "\n".join(all_lines[frag.start_line - 1 : frag.end_line])
             if not expected.endswith("\n"):
                 expected += "\n"

tests/test_yaml_diff.py

@@ -72,9 +72,9 @@ def test_diff_yaml_structure(yaml_test_runner: YamlTestRunner, case: YamlTestCas
     assert isinstance(fragments, list), f"[{case.id}] 'fragments' is not a list"
 
     if "fragment_count" in context:
-        assert context["fragment_count"] == len(fragments), (
-            f"[{case.id}] fragment_count ({context['fragment_count']}) " f"!= len(fragments) ({len(fragments)})"
-        )
+        assert context["fragment_count"] == len(
+            fragments
+        ), f"[{case.id}] fragment_count ({context['fragment_count']}) != len(fragments) ({len(fragments)})"
 
     for i, frag in enumerate(fragments):
         assert "path" in frag, f"[{case.id}] Fragment {i} missing 'path'"