styled components interpolated selectors dont generate newline

If we have multiple styled components interpolated and separated by comma, the expected newline after the comma is missing.

Styled Components allow interpolation of nested styled components, see here for the syntax.

Prettier will put css selectors separated by , on new lines, introduced here: https://github.com/prettier/prettier/pull/2047. This works in styled components using regular css selectors, see second block in the playground link. It only fails when we try to use interpolated styled components.

Prettier 1.18.2
Playground link

--parser babel

Input:

const A = styled(_A)`
  ${B}, ${C} {
    style: value;
  }
`

const A = styled(_A)`
  .classA, .classB {
    style: value;
  }
`

Output:

const A = styled(_A)`
  ${B}, ${C} {
    style: value;
  }
`;

const A = styled(_A)`
  .classA,
  .classB {
    style: value;
  }
`;

Expected behavior:

const A = styled(_A)`
  ${B},
  ${C} {
    style: value;
  }
`;

const A = styled(_A)`
  .classA,
  .classB {
    style: value;
  }
`;

Start with the linked Playground reproduction using the babel parser and compare the styled-component interpolation case with the regular CSS selector case. Trace the formatter path for comma-separated selectors; done means the interpolated selectors receive the same newline formatting as regular selectors while preserving the shown output.