Visual Studio Code Asciidoctor-PDF task (with problem matcher)

asciidoctor-tasks.json

{
  "version": "2.0.0",
  "tasks": [
    {
      "label": "Build document",
      "type": "shell",
      "command": "asciidoctor-pdf -r asciidoctor-diagram --out-file outfile.pdf infile.adoc",
      "group": {
        "kind": "build",
        "isDefault": true
      },
      "presentation": {
        "echo": true,
        "reveal": "silent",
        "focus": false,
        "panel": "dedicated"
      },
      "problemMatcher": {
        "owner": "asciidoc",
        "fileLocation": ["relative", "${workspaceFolder}"],
        "pattern": {
            "regexp": "^asciidoctor:\\s+(WARNING|ERROR):\\s+(.*):\\s+line\\s+(\\d+):\\s+(.*)$",
            "column": 0,
            "severity": 1,
            "file": 2,
            "line": 3,
            "message": 4
        }
      }
    }
  ]
}