csstree.lexer.matchProperty doesn't give an error on "filter" property with "blur(4px)empx"

[istarkov]

Example:

import * as csstree from "css-tree";
const ast = csstree.parse("blur(4px)empx", { context: "value" });
const matchResult = csstree.lexer.matchProperty("filter", ast);

console.log(JSON.stringify(matchResult));

Result JSON

{
  "matched": {
    "syntax": { "type": "Property", "name": "filter" },
    "match": [
      {
        "syntax": {
          "type": "Type",
          "name": "-ms-filter-function-list",
          "opts": null
        },
        "match": [
          {
            "syntax": {
              "type": "Type",
              "name": "-ms-filter-function",
              "opts": null
            },
            "match": [
              {
                "syntax": {
                  "type": "Type",
                  "name": "-ms-filter-function-legacy",
                  "opts": null
                },
                "match": [
                  {
                    "syntax": {
                      "type": "Type",
                      "name": "function-token",
                      "opts": null
                    },
                    "match": [
                      {
                        "syntax": null,
                        "token": "blur(",
                        "node": {
                          "type": "Function",
                          "loc": null,
                          "name": "blur",
                          "children": [
                            {
                              "type": "Dimension",
                              "loc": null,
                              "value": "4",
                              "unit": "px"
                            }
                          ]
                        }
                      }
                    ]
                  },
                  {
                    "syntax": {
                      "type": "Type",
                      "name": "any-value",
                      "opts": null
                    },
                    "match": [
                      {
                        "syntax": null,
                        "token": "4px",
                        "node": {
                          "type": "Dimension",
                          "loc": null,
                          "value": "4",
                          "unit": "px"
                        }
                      }
                    ]
                  },
                  {
                    "syntax": { "type": "Token", "value": ")" },
                    "token": ")",
                    "node": {
                      "type": "Function",
                      "loc": null,
                      "name": "blur",
                      "children": [
                        {
                          "type": "Dimension",
                          "loc": null,
                          "value": "4",
                          "unit": "px"
                        }
                      ]
                    }
                  }
                ]
              }
            ]
          },
          {
            "syntax": {
              "type": "Type",
              "name": "-ms-filter-function",
              "opts": null
            },
            "match": [
              {
                "syntax": {
                  "type": "Type",
                  "name": "-ms-filter-function-legacy",
                  "opts": null
                },
                "match": [
                  {
                    "syntax": {
                      "type": "Type",
                      "name": "ident-token",
                      "opts": null
                    },
                    "match": [
                      {
                        "syntax": null,
                        "token": "empx",
                        "node": {
                          "type": "Identifier",
                          "loc": null,
                          "name": "empx"
                        }
                      }
                    ]
                  }
                ]
              }
            ]
          }
        ]
      }
    ]
  },
  "iterations": 113,
  "error": null
}