diff options
| author | Jonas Toth <jonas.toth@gmail.com> | 2018-12-03 19:22:08 +0000 |
|---|---|---|
| committer | Jonas Toth <jonas.toth@gmail.com> | 2018-12-03 19:22:08 +0000 |
| commit | a95c588a42b63481935f9ef33e4eb04df6b20997 (patch) | |
| tree | e2dea97afa205e3470b78ec5739e0460264ceb83 /clang-tools-extra/docs | |
| parent | f53a9fdb51d53f5bbc4e489702e302320758616a (diff) | |
[clang-tidy] Recommit: Add the abseil-duration-comparison check
Summary:
This check finds instances where Duration values are being converted to a numeric value in a comparison expression, and suggests that the conversion happen on the other side of the expression to a Duration. See documentation for examples.
This also shuffles some code around so that the new check may perform in sone step simplifications also caught by other checks.
Compilation is unbroken, because the hash-function is now directly
specified for std::unordered_map, as 'enum class' does not compile as
key (seamingly only on some compilers).
Patch by hwright.
Reviewers: aaron.ballman, JonasToth, alexfh, hokein
Reviewed By: JonasToth
Subscribers: sammccall, Eugene.Zelenko, xazax.hun, cfe-commits, mgorny
Tags: #clang-tools-extra
Differential Revision: https://reviews.llvm.org/D54737
Diffstat (limited to 'clang-tools-extra/docs')
| -rw-r--r-- | clang-tools-extra/docs/ReleaseNotes.rst | 6 | ||||
| -rw-r--r-- | clang-tools-extra/docs/clang-tidy/checks/abseil-duration-comparison.rst | 33 | ||||
| -rw-r--r-- | clang-tools-extra/docs/clang-tidy/checks/list.rst | 1 |
3 files changed, 40 insertions, 0 deletions
diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst index c7229df7086..19079686059 100644 --- a/clang-tools-extra/docs/ReleaseNotes.rst +++ b/clang-tools-extra/docs/ReleaseNotes.rst @@ -67,6 +67,12 @@ The improvements are... Improvements to clang-tidy -------------------------- +- New :doc:`abseil-duration-comparison + <clang-tidy/checks/abseil-duration-comparison>` check. + + Checks for comparisons which should be done in the ``absl::Duration`` domain + instead of the float of integer domains. + - New :doc:`abseil-duration-division <clang-tidy/checks/abseil-duration-division>` check. diff --git a/clang-tools-extra/docs/clang-tidy/checks/abseil-duration-comparison.rst b/clang-tools-extra/docs/clang-tidy/checks/abseil-duration-comparison.rst new file mode 100644 index 00000000000..6df0514dec6 --- /dev/null +++ b/clang-tools-extra/docs/clang-tidy/checks/abseil-duration-comparison.rst @@ -0,0 +1,33 @@ +.. title:: clang-tidy - abseil-duration-comparison + +abseil-duration-comparison +========================== + +Checks for comparisons which should be in the ``absl::Duration`` domain instead +of the floating point or integer domains. + +N.B.: In cases where a ``Duration`` was being converted to an integer and then +compared against a floating-point value, truncation during the ``Duration`` +conversion might yield a different result. In practice this is very rare, and +still indicates a bug which should be fixed. + +Examples: + +.. code-block:: c++ + + // Original - Comparison in the floating point domain + double x; + absl::Duration d; + if (x < absl::ToDoubleSeconds(d)) ... + + // Suggested - Compare in the absl::Duration domain instead + if (absl::Seconds(x) < d) ... + + + // Original - Comparison in the integer domain + int x; + absl::Duration d; + if (x < absl::ToInt64Microseconds(d)) ... + + // Suggested - Compare in the absl::Duration domain instead + if (absl::Microseconds(x) < d) ... diff --git a/clang-tools-extra/docs/clang-tidy/checks/list.rst b/clang-tools-extra/docs/clang-tidy/checks/list.rst index 7fa19471895..e3528ae90e8 100644 --- a/clang-tools-extra/docs/clang-tidy/checks/list.rst +++ b/clang-tools-extra/docs/clang-tidy/checks/list.rst @@ -4,6 +4,7 @@ Clang-Tidy Checks ================= .. toctree:: + abseil-duration-comparison abseil-duration-division abseil-duration-factory-float abseil-duration-factory-scale |