[PATCH] D43120: [clang-tidy] New checker for exceptions that are created but not thrown

[Whisperity via Phabricator via cfe-commits]

whisperity requested changes to this revision.
whisperity added inline comments.
This revision now requires changes to proceed.


================
Comment at: clang-tidy/misc/ThrowKeywordMissingCheck.cpp:21
+void ThrowKeywordMissingCheck::registerMatchers(MatchFinder *Finder) {
+  // This is a C++ only checker.
+  if (!getLangOpts().CPlusPlus)
----------------
Superfluous comment, this can be removed.


================
Comment at: clang-tidy/misc/ThrowKeywordMissingCheck.cpp:32
+           hasType(cxxRecordDecl(
+               isSameOrDerivedFrom(matchesName("[Ee]xception|EXCEPTION")))),
+           unless(anyOf(hasAncestor(stmt(
----------------
`matchesName` says

> Does not match typedefs of an underlying type with the given name.

Does your check find the following case?

```
typedef std::exception ERROR_BASE;
class my_error : public ERROR_BASE {
  /* Usual yadda. */
};

int main() {
  my_error();
}
```



================
Comment at: clang-tidy/misc/ThrowKeywordMissingCheck.cpp:46
+      Result.Nodes.getNodeAs<Expr>("temporary-exception-not-thrown");
+  diag(TemporaryExpr->getLocStart(), "exception created but is not thrown");
+}
----------------
Either use passive for both subsentences or don't use passive at all. Maybe one of the following could be a better wording:

> exception instantied and not thrown

> exception is constructed but is not thrown

> exception construction without a throw statement


================
Comment at: test/clang-tidy/misc-throw-keyword-missing.cpp:23
+// std::exception and std::runtime_error declaration
+struct exception{
+  exception();
----------------
Please format the code. Why isn't there a space before `{`?


================
Comment at: test/clang-tidy/misc-throw-keyword-missing.cpp:29
+
+struct runtime_error : public exception{
+  explicit runtime_error( const std::string& what_arg );
----------------
Format here too.


Repository:
  rCTE Clang Tools Extra

https://reviews.llvm.org/D43120