single-line comments break highlighting on the next line

[AdamRaichu]

On GitHub.com, C++ code is incorrectly highlighted after a line that contains a // comment.

Example code demonstrating the problem:

const byte hello = 1;  // This is a comment
const byte world = 2;  // `const` should be highlighted, but it is not

const byte foo = 3; /* This problem does not occur with multiline comments. */
/* Multiple
lines */
const byte bar = 4;

// This comment breaks highlighting as well.
const byte a = 5;
const byte b = 6;

// This also breaks highlighting in other ways
int main() {}

int test() {}

// Even this breaks
x_y();

y_z();

// Another example
a_z(); a_z();

Reporting here because of instructions in this repo.

[sethrj]

It took me literally half an hour of digging through source code, github support, and google, to find this.

As of some recent update, Github syntax highlighting for C++ is terribly broken by this error, especially if you have multi-line comments following a single-line comment as our codebase does:

namespace celeritas
{
//---------------------------------------------------------------------------//
/*!
 * Calculate the transport cross section for the Wentzel OK and VI model.
 *
 * \note This performs the same calculation as Geant4's
 * G4WentzelOKandVIxSection::ComputeTransportCrossSectionPerAtom.
 */
class WentzelTransportXsCalculator
{
  public:
    //!@{
    //! \name Type aliases
    using XsUnits = units::Native;  // [len^2]
    using Charge = units::ElementaryCharge;
    using Mass = units::MevMass;
    using MomentumSq = units::MevMomentumSq;
    //!@}
   /* and so forth */
};

The first single-line comment causes the /*! block highlight to be ignored, which then causes the apostrophe inside the comment to be interpreted as a character string...

(this renders for me, as of Feb 2024, as )

[sethrj]

I don't think this is a bug in this repository because the issue only recently started manifesting on GitHub, and the last commit for this repository was years ago.