From 1f329823222b1016b13952976a1616f3dc008269 Mon Sep 17 00:00:00 2001 From: Zac-HD Date: Sun, 12 Dec 2021 14:50:44 +1100 Subject: [PATCH] Cope with `stat` errors If we get an error when accessing the mtime of a cache file, we should handle that as if the cache is unusable for any other reason. --- mypy/build.py | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/mypy/build.py b/mypy/build.py index 4398b0281d99..d786922a4564 100644 --- a/mypy/build.py +++ b/mypy/build.py @@ -1311,8 +1311,11 @@ def validate_meta(meta: Optional[CacheMeta], id: str, path: Optional[str], assert path is not None, "Internal error: meta was provided without a path" if not manager.options.skip_cache_mtime_checks: # Check data_json; assume if its mtime matches it's good. - # TODO: stat() errors - data_mtime = manager.getmtime(meta.data_json) + try: + data_mtime = manager.getmtime(meta.data_json) + except OSError: + manager.log('Metadata abandoned for {}: failed to stat data_json'.format(id)) + return None if data_mtime != meta.data_mtime: manager.log('Metadata abandoned for {}: data cache is modified'.format(id)) return None @@ -1508,9 +1511,6 @@ def write_cache(id: str, path: str, tree: MypyFile, # Write data cache file, if applicable # Note that for Bazel we don't record the data file's mtime. if old_interface_hash == interface_hash: - # If the interface is unchanged, the cached data is guaranteed - # to be equivalent, and we only need to update the metadata. - data_mtime = manager.getmtime(data_json) manager.trace("Interface for {} is unchanged".format(id)) else: manager.trace("Interface for {} has changed".format(id)) @@ -1527,7 +1527,12 @@ def write_cache(id: str, path: str, tree: MypyFile, # Both have the effect of slowing down the next run a # little bit due to an out-of-date cache file. return interface_hash, None + + try: data_mtime = manager.getmtime(data_json) + except OSError: + manager.log("Error in os.stat({!r}), skipping cache write".format(data_json)) + return interface_hash, None mtime = 0 if bazel else int(st.st_mtime) size = st.st_size