Make junit.xml reproducible in bazel mode by clearing timings

mypy/main.py

@@ -1719,6 +1719,9 @@ def maybe_write_junit_xml(
     options: Options,
 ) -> None:
     if options.junit_xml:
+        if options.bazel:
+            # Elapsed time would make the output non-reproducible.
+            td = 0.0
         py_version = f"{options.python_version[0]}_{options.python_version[1]}"
         if options.junit_format == "global":
             util.write_junit_xml(

mypy/test/testutil.py

@@ -1,9 +1,12 @@
 from __future__ import annotations
 
 import os
+import tempfile
 from unittest import TestCase, mock
 
 from mypy.inspections import parse_location
+from mypy.main import maybe_write_junit_xml
+from mypy.options import Options
 from mypy.util import _generate_junit_contents, get_terminal_width
 
 
@@ -109,3 +112,15 @@ def test_serious_error(self) -> None:
             platform="test-plat",
         )
         assert result == expected
+
+    def test_junit_time_is_zero_in_bazel_mode(self) -> None:
+        # Output must be reproducible under Bazel, so elapsed time is not included.
+        with tempfile.TemporaryDirectory() as tmpdir:
+            options = Options()
+            options.bazel = True
+            options.junit_xml = os.path.join(tmpdir, "junit.xml")
+            maybe_write_junit_xml(1.23, False, [], {}, options)
+            with open(options.junit_xml) as f:
+                result = f.read()
+        assert 'time="0.000"' in result
+        assert "1.230" not in result

mypyc/build.py

@@ -199,6 +199,9 @@ def fail(message: str) -> NoReturn:
 def emit_messages(options: Options, messages: list[str], dt: float, serious: bool = False) -> None:
     # ... you know, just in case.
     if options.junit_xml:
+        if options.bazel:
+            # Elapsed time would make the output non-reproducible.
+            dt = 0.0
         py_version = f"{options.python_version[0]}_{options.python_version[1]}"
         write_junit_xml(
             dt,

mypyc/test/test_misc.py

@@ -4,7 +4,8 @@
 import tempfile
 import unittest
 
-from mypyc.build import get_header_deps, resolve_cfile_deps
+from mypy.options import Options
+from mypyc.build import emit_messages, get_header_deps, resolve_cfile_deps
 from mypyc.ir.ops import BasicBlock
 from mypyc.ir.pprint import format_blocks, generate_names_for_ir
 from mypyc.irbuild.ll_builder import LowLevelIRBuilder
@@ -24,6 +25,18 @@ def test_debug_op(self) -> None:
         code = format_blocks([block], names, {})
         assert code[:-1] == ["L0:", "    r0 = 'foo'", "    CPyDebug_PrintObject(r0)"]
 
+    def test_junit_time_is_zero_in_bazel_mode(self) -> None:
+        # Output must be reproducible under Bazel, so elapsed time is not included.
+        with tempfile.TemporaryDirectory() as tmpdir:
+            options = Options()
+            options.bazel = True
+            options.junit_xml = os.path.join(tmpdir, "junit.xml")
+            emit_messages(options, [], 1.23)
+            with open(options.junit_xml) as f:
+                result = f.read()
+        assert 'time="0.000"' in result
+        assert "1.230" not in result
+
 
 class TestHeaderDeps(unittest.TestCase):
     """