Move message to constant

hypothesis-python/src/hypothesis/internal/scrutineer.py

@@ -94,6 +94,7 @@ def get_explaining_locations(traces):
     "Explanation:",
     "    These lines were always and only run by failing examples:",
 )
+HAD_TRACE = "    We didn't try to explain this, because sys.gettrace()="
 
 
 def make_report(explanations, cap_lines_at=5):
@@ -114,8 +115,9 @@ def make_report(explanations, cap_lines_at=5):
 
 def explanatory_lines(traces, settings):
     if Phase.explain in settings.phases and sys.gettrace() and not traces:
-        msg = "    We didn't try to explain this, because sys.gettrace()="
-        return defaultdict(lambda: [EXPLANATION_STUB[0], msg + repr(sys.gettrace())])
+        return defaultdict(
+            lambda: [EXPLANATION_STUB[0], HAD_TRACE + repr(sys.gettrace())]
+        )
     # Return human-readable report lines summarising the traces
     explanations = get_explaining_locations(traces)
     max_lines = 5 if settings.verbosity <= Verbosity.normal else 100

hypothesis-python/tests/cover/test_scrutineer.py

@@ -19,7 +19,7 @@
 import pytest
 
 from hypothesis.internal.compat import PYPY
-from hypothesis.internal.scrutineer import make_report
+from hypothesis.internal.scrutineer import HAD_TRACE, make_report
 
 BUG_MARKER = "# BUG"
 PRELUDE = """
@@ -88,13 +88,8 @@ def test_cannot_explain_message(testdir):
 
         code = PRELUDE + TRIVIAL
         test_file = testdir.makepyfile(code)
-        result = testdir.runpytest_inprocess(test_file, "--tb=native")
-        result.stdout.re_match_lines(
-            [
-                r"Explanation:",
-                fr"""\s*{re.escape("We didn't try to explain this, because sys.gettrace()=")}.*""",
-            ],
-            consecutive=True,
+        testdir.runpytest_inprocess(test_file, "--tb=native").stdout.re_match_lines(
+            [r"Explanation:", re.escape(HAD_TRACE)], consecutive=True
         )
     finally:
         if no_tracer: