issue with escodegen.attachComments and leading block comments

class.js

/**
 * @class MyClass
 */
function MyClass() {}

class.json

{
  "type": "Program",
  "body": [
    {
      "type": "FunctionDeclaration",
      "id": {
        "type": "Identifier",
        "name": "MyClass",
        "range": [
          35,
          42
        ],
        "loc": {
          "start": {
            "line": 4,
            "column": 9
          },
          "end": {
            "line": 4,
            "column": 16
          }
        }
      },
      "params": [],
      "defaults": [],
      "body": {
        "type": "BlockStatement",
        "body": [],
        "range": [
          45,
          47
        ],
        "loc": {
          "start": {
            "line": 4,
            "column": 19
          },
          "end": {
            "line": 4,
            "column": 21
          }
        }
      },
      "rest": null,
      "generator": false,
      "expression": false,
      "range": [
        26,
        47
      ],
      "loc": {
        "start": {
          "line": 4,
          "column": 0
        },
        "end": {
          "line": 4,
          "column": 21
        }
      }
    }
  ],
  "range": [
    26,
    47
  ],
  "loc": {
    "start": {
      "line": 4,
      "column": 0
    },
    "end": {
      "line": 4,
      "column": 21
    }
  },
  "comments": [
    {
      "type": "Block",
      "value": "*\n * @class MyClass\n ",
      "range": [
        0,
        25
      ],
      "loc": {
        "start": {
          "line": 1,
          "column": 0
        },
        "end": {
          "line": 3,
          "column": 3
        }
      }
    }
  ],
  "tokens": [
    {
      "type": "Keyword",
      "value": "function",
      "range": [
        26,
        34
      ],
      "loc": {
        "start": {
          "line": 4,
          "column": 0
        },
        "end": {
          "line": 4,
          "column": 8
        }
      }
    },
    {
      "type": "Identifier",
      "value": "MyClass",
      "range": [
        35,
        42
      ],
      "loc": {
        "start": {
          "line": 4,
          "column": 9
        },
        "end": {
          "line": 4,
          "column": 16
        }
      }
    },
    {
      "type": "Punctuator",
      "value": "(",
      "range": [
        42,
        43
      ],
      "loc": {
        "start": {
          "line": 4,
          "column": 16
        },
        "end": {
          "line": 4,
          "column": 17
        }
      }
    },
    {
      "type": "Punctuator",
      "value": ")",
      "range": [
        43,
        44
      ],
      "loc": {
        "start": {
          "line": 4,
          "column": 17
        },
        "end": {
          "line": 4,
          "column": 18
        }
      }
    },
    {
      "type": "Punctuator",
      "value": "{",
      "range": [
        45,
        46
      ],
      "loc": {
        "start": {
          "line": 4,
          "column": 19
        },
        "end": {
          "line": 4,
          "column": 20
        }
      }
    },
    {
      "type": "Punctuator",
      "value": "}",
      "range": [
        46,
        47
      ],
      "loc": {
        "start": {
          "line": 4,
          "column": 20
        },
        "end": {
          "line": 4,
          "column": 21
        }
      }
    }
  ],
  "leadingComments": [
    {
      "type": "Block",
      "value": "*\n * @class MyClass\n ",
      "range": {
        "0": 0,
        "1": 25
      },
      "loc": {
        "start": {
          "line": 1,
          "column": 0
        },
        "end": {
          "line": 3,
          "column": 3
        }
      },
      "extendedRange": [
        0,
        26
      ]
    }
  ]
}