feat: add PR complexity scorer — estimate review effort\n\nImplements issue #135: a script that analyzes open PRs and computes\na complexity score (1-10) based on files changed, lines added/removed,\ndependency changes, and test coverage delta. Also estimates review time.\n\nThe scorer can be run with --dry-run to preview or --apply to post\nscore comments directly on PRs.\n\nOutput: metrics/pr_complexity.json with full analysis.\n\nCloses #135

scripts/test_pr_complexity_scorer.py

@@ -0,0 +1,170 @@
+#!/usr/bin/env python3
+"""
+Tests for PR Complexity Scorer — unit tests for the scoring logic.
+"""
+
+import sys
+from pathlib import Path
+
+sys.path.insert(0, str(Path(__file__).parent))
+
+from pr_complexity_scorer import (
+    score_pr,
+    is_dependency_file,
+    is_test_file,
+    TIME_PER_POINT,
+    SMALL_FILES,
+    MEDIUM_FILES,
+    LARGE_FILES,
+    SMALL_LINES,
+    MEDIUM_LINES,
+    LARGE_LINES,
+)
+
+PASS = 0
+FAIL = 0
+
+def test(name):
+    def decorator(fn):
+        global PASS, FAIL
+        try:
+            fn()
+            PASS += 1
+            print(f"  [PASS] {name}")
+        except AssertionError as e:
+            FAIL += 1
+            print(f"  [FAIL] {name}: {e}")
+        except Exception as e:
+            FAIL += 1
+            print(f"  [FAIL] {name}: Unexpected error: {e}")
+    return decorator
+
+def assert_eq(a, b, msg=""):
+    if a != b:
+        raise AssertionError(f"{msg} expected {b!r}, got {a!r}")
+
+def assert_true(v, msg=""):
+    if not v:
+        raise AssertionError(msg or "Expected True")
+
+def assert_false(v, msg=""):
+    if v:
+        raise AssertionError(msg or "Expected False")
+
+
+print("=== PR Complexity Scorer Tests ===\n")
+
+print("-- File Classification --")
+
+@test("dependency file detection — requirements.txt")
+def _():
+    assert_true(is_dependency_file("requirements.txt"))
+    assert_true(is_dependency_file("src/requirements.txt"))
+    assert_false(is_dependency_file("requirements_test.txt"))
+
+@test("dependency file detection — pyproject.toml")
+def _():
+    assert_true(is_dependency_file("pyproject.toml"))
+    assert_false(is_dependency_file("myproject.py"))
+
+@test("test file detection — pytest style")
+def _():
+    assert_true(is_test_file("tests/test_api.py"))
+    assert_true(is_test_file("test_module.py"))
+    assert_true(is_test_file("src/module_test.py"))
+
+@test("test file detection — other frameworks")
+def _():
+    assert_true(is_test_file("spec/feature_spec.rb"))
+    assert_true(is_test_file("__tests__/component.test.js"))
+    assert_false(is_test_file("testfixtures/helper.py"))
+
+
+print("\n-- Scoring Logic --")
+
+@test("small PR gets low score (1-3)")
+def _():
+    score, minutes, _ = score_pr(
+        files_changed=3,
+        additions=50,
+        deletions=10,
+        has_dependency_changes=False,
+        test_coverage_delta=None
+    )
+    assert_true(1 <= score <= 3, f"Score should be low, got {score}")
+    assert_true(minutes < 20)
+
+@test("medium PR gets medium score (4-6)")
+def _():
+    score, minutes, _ = score_pr(
+        files_changed=15,
+        additions=400,
+        deletions=100,
+        has_dependency_changes=False,
+        test_coverage_delta=None
+    )
+    assert_true(4 <= score <= 6, f"Score should be medium, got {score}")
+    assert_true(20 <= minutes <= 45)
+
+@test("large PR gets high score (7-9)")
+def _():
+    score, minutes, _ = score_pr(
+        files_changed=60,
+        additions=3000,
+        deletions=1500,
+        has_dependency_changes=True,
+        test_coverage_delta=None
+    )
+    assert_true(7 <= score <= 9, f"Score should be high, got {score}")
+    assert_true(minutes >= 45)
+
+@test("dependency changes boost score")
+def _():
+    base_score, _, _ = score_pr(
+        files_changed=10, additions=200, deletions=50,
+        has_dependency_changes=False, test_coverage_delta=None
+    )
+    dep_score, _, _ = score_pr(
+        files_changed=10, additions=200, deletions=50,
+        has_dependency_changes=True, test_coverage_delta=None
+    )
+    assert_true(dep_score > base_score, f"Deps: {base_score} -> {dep_score}")
+
+@test("adding tests lowers complexity")
+def _():
+    base_score, _, _ = score_pr(
+        files_changed=8, additions=150, deletions=20,
+        has_dependency_changes=False, test_coverage_delta=None
+    )
+    better_score, _, _ = score_pr(
+        files_changed=8, additions=180, deletions=20,
+        has_dependency_changes=False, test_coverage_delta=3
+    )
+    assert_true(better_score < base_score, f"Tests: {base_score} -> {better_score}")
+
+@test("removing tests increases complexity")
+def _():
+    base_score, _, _ = score_pr(
+        files_changed=8, additions=150, deletions=20,
+        has_dependency_changes=False, test_coverage_delta=None
+    )
+    worse_score, _, _ = score_pr(
+        files_changed=8, additions=150, deletions=20,
+        has_dependency_changes=False, test_coverage_delta=-2
+    )
+    assert_true(worse_score > base_score, f"Remove tests: {base_score} -> {worse_score}")
+
+@test("score bounded 1-10")
+def _():
+    for files, adds, dels in [(1, 10, 5), (100, 10000, 5000)]:
+        score, _, _ = score_pr(files, adds, dels, False, None)
+        assert_true(1 <= score <= 10, f"Score {score} out of range")
+
+@test("estimated minutes exist for all scores")
+def _():
+    for s in range(1, 11):
+        assert_true(s in TIME_PER_POINT, f"Missing time for score {s}")
+
+
+print(f"\n=== Results: {PASS} passed, {FAIL} failed ===")
+sys.exit(0 if FAIL == 0 else 1)