https://bugs.llvm.org/show_bug.cgi?id=50069
When clang-tidy sees:
```
if (true) [[unlikely]] {
...
}
```
It thinks the braces are missing and add them again.
```
if (true) { [[unlikely]] {
...
}
}
```
This revision aims to prevent that incorrect code generation
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D105479
Add a check for enforcing minimum length for variable names. A default
minimum length of three characters is applied to regular variables
(including function parameters). Loop counters and exception variables
have a minimum of two characters. Additionally, the 'i', 'j' and 'k'
are accepted as legacy values.
All three sizes, as well as the list of accepted legacy loop counter
names are configurable.
Some files still contained the old University of Illinois Open Source
Licence header. This patch replaces that with the Apache 2 with LLVM
Exception licence.
Differential Revision: https://reviews.llvm.org/D107528
This patch tries to fix command line too long problem on Windows for
https://reviews.llvm.org/D86671.
The command line is too long with check_clang_tidy.py program on Windows,
because the configuration is long for regression test. Fix this issue by
passing the settings in file instead.
Differential Revision: https://reviews.llvm.org/D107325
Finds function calls where the call arguments might be provided in an
incorrect order, based on the comparison (via string metrics) of the
parameter names and the argument names against each other.
A diagnostic is emitted if an argument name is similar to a *different*
parameter than the one currently passed to, and it is sufficiently
dissimilar to the one it **is** passed to currently.
False-positive warnings from this check are useful to indicate bad
naming convention issues, even if a swap isn't necessary.
This check does not generate FixIts.
Originally implemented by @varjujan as his Master's Thesis work.
The check was subsequently taken over by @barancsuk who added type
conformity checks to silence false positive matches.
The work by @whisperity involved driving the check's review and fixing
some more bugs in the process.
Reviewed By: aaron.ballman, alexfh
Differential Revision: http://reviews.llvm.org/D20689
Co-authored-by: János Varjú <varjujanos2@gmail.com>
Co-authored-by: Lilla Barancsuk <barancsuklilla@gmail.com>
(this was originally part of https://reviews.llvm.org/D96281 and has been split off into its own patch)
If a macro is used within a function, the code inside the macro
doesn't make the code less readable. Instead, for a reader a macro is
more like a function that is called. Thus the code inside a macro
shouldn't increase the complexity of the function in which it is called.
Thus the flag 'IgnoreMacros' is added. If set to 'true' code inside
macros isn't considered during analysis.
This isn't perfect, as now the code of a macro isn't considered at all,
even if it has a high cognitive complexity itself. It might be better if
a macro is considered in the analysis like a function and gets its own
cognitive complexity. Implementing such an analysis seems to be very
complex (if possible at all with the given AST), so we give the user the
option to either ignore macros completely or to let the expanded code
count to the calling function's complexity.
See the code example from vgeof (originally added as note in https://reviews.llvm.org/D96281)
bool doStuff(myClass* objectPtr){
if(objectPtr == nullptr){
LOG_WARNING("empty object");
return false;
}
if(objectPtr->getAttribute() == nullptr){
LOG_WARNING("empty object");
return false;
}
use(objectPtr->getAttribute());
}
The LOG_WARNING macro itself might have a high complexity, but it do not make the
the function more complex to understand like e.g. a 'printf'.
By default 'IgnoreMacros' is set to 'false', which is the original behavior of the check.
Reviewed By: lebedev.ri, alexfh
Differential Revision: https://reviews.llvm.org/D98070
The deprecation notice was cherrypicked to the release branch in f8b3298924 so its safe to remove this for the 13.X release cycle.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D98612
If a identifier has a correct prefix/suffix but a bad case, the fix won't strip them when computing the correct case, leading to duplication when the are added back.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D98521
Often you are only interested in the overall cognitive complexity of a
function and not every individual increment. Thus the flag
'DescribeBasicIncrements' is added. If it is set to 'true', each increment
is flagged. Otherwise, only the complexity of function with complexity
of at least the threshold are flagged.
By default 'DescribeBasisIncrements' is set to 'true', which is the original behavior of the check.
Added a new test for different flag combinations.
(The option to ignore macros which was original part of this patch will be added in another path)
Reviewed By: lebedev.ri
Differential Revision: https://reviews.llvm.org/D96281
Adds an option, `PreferResetCall`, currently defaulted to `false`, to the check.
When `true` the check will refactor by calling the `reset` member function.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D97630
The interface served a purpose, but since the ability to emit diagnostics when parsing configuration was added, its become mostly redundant. Emitting the diagnostic and removing the boilerplate is much cleaner.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D97614
Fix up cases where diag is called by piecing together a string in favour of placeholders.
Fix up cases where select could be used instead of duplicating the message for sake of 1 word difference.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D97488
Because it no longer relies on finding implicit casts, this check now
works on templates which are not instantiated in the translation unit.
Differential Revision: https://reviews.llvm.org/D96138
Use IgnoreUnlessSpelledInSource to make the matcher code smaller and
more visibly-related to the code.
Differential Revision: https://reviews.llvm.org/D91303
Use mapAnyOf() and matchers based on it.
Use of binaryOperation() means that modernize-loop-convert and
readability-container-size-empty can now be used with rewritten binary
operators.
Differential Revision: https://reviews.llvm.org/D94131
readability-container-size-empty currently modifies source code based on
AST nodes in template instantiations, which means that it makes
transformations based on substituted types. This can lead to
transforming code to be broken.
Change the matcher implementation to ignore template instantiations
explicitly, and add a matcher to explicitly handle template declarations
instead of instantiations.
Differential Revision: https://reviews.llvm.org/D91302
Add methods for emitting diagnostics with no location as well as a special diagnostic for configuration errors.
These show up in the errors as [clang-tidy-config].
The reason to use a custom name rather than the check name is to distinguish the error isn't the same category as the check that reported it.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D91885
This is partly in preparation for an upcoming change that can change the
order in which DeclContext lookup results are presented.
In passing, fix some obvious errors where name lookup's notion of a
"static member function" missed static member function templates, and
where its notion of "same set of declarations" was confused by the same
declarations appearing in a different order.
The idea of suppressing naming checks for variables is to support code bases that allow short variables named e.g 'x' and 'i' without prefix/suffixes or casing styles. This was originally proposed as a 'ShortSizeThreshold' however has been made more generic with a regex to suppress identifier naming checks for those that match.
Reviewed By: njames93, aaron.ballman
Differential Revision: https://reviews.llvm.org/D90282
std::string_view("") produces a string_view instance that compares
equal to std::string_view(), but requires more complex initialization
(storing the address of the string literal, rather than zeroing).
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D91009
Consider this code:
```
if (Cond) {
#ifdef X_SUPPORTED
X();
#else
return;
#endif
} else {
Y();
}
Z();```
In this example, if `X_SUPPORTED` is not defined, currently we'll get a warning from the else-after-return check. However If we apply that fix, and then the code is recompiled with `X_SUPPORTED` defined, we have inadvertently changed the behaviour of the if statement due to the else being removed. Code flow when `Cond` is `true` will be:
```
X();
Y();
Z();```
where as before the fix it was:
```
X();
Z();```
This patch adds checks that guard against `#endif` directives appearing between the control flow interrupter and the else and not applying the fix if they are detected.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D91485
Add IgnoreMainLikeFunctions to the per file config. This can be extended for new options added to the check easily.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D90832
Remove the need to heap allocate a string for each style option lookup while reading or writing options.p
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D90244
Added option `ScopedEnumConstant(Prefix|Case|Suffix)` to readability-identitied-naming.
This controls the style for constants in scoped enums, declared as enum (class|struct).
If this option is unspecified the EnumConstant style will be used instead.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D89407
Update clang-tools-extra, clang/tools, clang/unittests to migrate from
`SourceManager::getBuffer`, which returns an always dereferenceable
`MemoryBuffer*`, to `getBufferOrNone` or `getBufferOrFake`, both of
which return a `MemoryBufferRef`, depending on whether the call site was
checking for validity of the buffer. No functionality change intended.
Differential Revision: https://reviews.llvm.org/D89416
Currently, there is basically just one clang-tidy check to impose
some sanity limits on functions - `clang-tidy-readability-function-size`.
It is nice, allows to limit line count, total number of statements,
number of branches, number of function parameters (not counting
implicit `this`), nesting level.
However, those are simple generic metrics. It is still trivially possible
to write a function, which does not violate any of these metrics,
yet is still rather unreadable.
Thus, some additional, slightly more complicated metric is needed.
There is a well-known [[ https://en.wikipedia.org/wiki/Cyclomatic_complexity | Cyclomatic complexity]], but certainly has its downsides.
And there is a [[ https://www.sonarsource.com/docs/CognitiveComplexity.pdf | COGNITIVE COMPLEXITY by SonarSource ]], which is available for opensource on https://sonarcloud.io/.
This check checks function Cognitive Complexity metric, and flags
the functions with Cognitive Complexity exceeding the configured limit.
The default limit is `25`, same as in 'upstream'.
The metric is implemented as per [[ https://www.sonarsource.com/docs/CognitiveComplexity.pdf | COGNITIVE COMPLEXITY by SonarSource ]] specification version 1.2 (19 April 2017), with two notable exceptions:
* `preprocessor conditionals` (`#ifdef`, `#if`, `#elif`, `#else`,
`#endif`) are not accounted for.
Could be done. Currently, upstream does not account for them either.
* `each method in a recursion cycle` is not accounted for.
It can't be fully implemented, because cross-translational-unit
analysis would be needed, which is not possible in clang-tidy.
Thus, at least right now, i completely avoided implementing it.
There are some further possible improvements:
* Are GNU statement expressions (`BinaryConditionalOperator`) really free?
They should probably cause nesting level increase,
and complexity level increase when they are nested within eachother.
* Microsoft SEH support
* ???
Reviewed By: aaron.ballman, JonasToth, lattner
Differential Revision: https://reviews.llvm.org/D36836
This change groups
* Rename: `ignoreParenBaseCasts` -> `IgnoreParenBaseCasts` for uniformity
* Rename: `IgnoreConversionOperator` -> `IgnoreConversionOperatorSingleStep` for uniformity
* Inline `IgnoreNoopCastsSingleStep` into a lambda inside `IgnoreNoopCasts`
* Refactor `IgnoreUnlessSpelledInSource` to make adequate use of `IgnoreExprNodes`
Differential Revision: https://reviews.llvm.org/D86880