This my test data, will wrong.

[zh-pan]

I don't know if this is bad data? If so, what are the features?

 var vertices = [
        -2428, 1634, 0, -2425, 1471, 0,
        -2409, 1156, 0, -2384, 842, 0,
        -2349, 529, 0, -2303, 217, 0,
        -2248, -92, 0, -2183, -401, 0,
        -2138, -588, 0, -2138, -681, 0,
        -2163, -681, 0, -2163, -1570, 0,
        -2138, -1570, 0, -2138, -1708, 0,
        2641, -1708, 0, 2641, -29, 0,
        3200, -29, 0, 3200, 1634, 0,

        -1845, -1692, 0, -930, -1692, 0,
        -930, -1387, 0, -1845, -1387, 0,

        -1235, -1387, 0, -321, -1387, 0,
        -321, -1083, 0, -1235, -1083, 0,

        -1540, -1083, 0, -625, -1083, 0,
        -625, -778, 0, -1540, -778, 0
    ];
    var holeIndices = [18, 22, 26];
    var indices = earcut(vertices, holeIndices, 3);
    var deviation = earcut.deviation(vertices, holeIndices, 3, indices);// The deviation not equal 0 !!!