[clang-tidy] bugprone-throw-keyword-missing false negatives from hasAncestor skipping too much

[5chmidti]

The matcher is using hasAncestor and could be skipping many different issues, simply because they have an ancestor node (e.g., VarDecl) but that node is not closely related to the construct expression itself.

struct RegularException {
    RegularException(int);
};
void foo() {
    const auto var = []() {
        RegularException{0};  // FN, ignored because of `hasAncestor(varDecl())`
        return 0;
    };
}

struct Bar {
    Bar() : v{0} {
        RegularException{0};  // FN, ignored because of `hasAncestor(cxxConstructorDecl())`
    }
    int v;
};

https://godbolt.org/z/6br6f91vc

[llvmbot]

@llvm/issue-subscribers-clang-tidy

Author: Julian Schmidt (5chmidti)

The matcher is using `hasAncestor` and could be skipping many different issues, simply because they have an ancestor node (e.g., `VarDecl`) but that node is not closely related to the construct expression itself.

struct RegularException {
    RegularException(int);
};
void foo() {
    const auto var = []() {
        RegularException{0};  // FN, ignored because of `hasAncestor(varDecl())`
        return 0;
    };
}

struct Bar {
    Bar() : v{0} {
        RegularException{0};  // FN, ignored because of `hasAncestor(cxxConstructorDecl())`
    }
    int v;
};

https://godbolt.org/z/6br6f91vc