bk2018/node_modules/objection/lib/queryBuilder/parsers/relationExpressionParser.pegjs

start =
  expr:expression {
    let node = { $name: null, $relation: null, $modify: [], $recursive: false, $allRecursive: false };

    if (expr.$name === '*') {
      node.$allRecursive = true;
    } else {
      node[expr.$name] = expr;
    }

    return node;
  }
  /
  list:listExpression {
    let node = { $name: null, $relation: null, $modify: [], $recursive: false, $allRecursive: false };

    list.forEach(expr => {
      node[expr.$name] = expr;
    });

    return node;
  }

expression =
  name:name args:args? alias:alias? list:subListExpression {
    let node = { $name: alias || name, $relation: name, $modify: args || [], $recursive: false, $allRecursive: false };

    list.forEach(expr => {
      node[expr.$name] = expr;
    });

    return node;
  }
  /
  name:name args:args? alias:alias? expr:subExpression? {
    let node = { $name: alias || name, $relation: name, $modify: args || [], $recursive: false, $allRecursive: false };

    if (expr) {
      const match = /^\^(\d*)$/.exec(expr.$name);

      if (match) {
        if (match[1]) {
          node.$recursive = parseInt(match[1], 10);
        } else {
          node.$recursive = true;
        }
      } else if (expr.$name === '*') {
        node.$allRecursive = true;
      } else {
        node[expr.$name] = expr;
      }
    }

    return node;
  }

alias =
  ws+ "as" ws+ alias:name {
    return alias;
  }

name =
  name:char+ {
    return name.join('');
  }

char =
  [^\[\]\(\),\. \t\r\n]

args =
  ws* "(" args:argListItem* ws* ")" {
    return args;
  }

argListItem =
  ws* arg:name ws* ","? {
    return arg;
  }

ws =
  [ \t\r\n]

subListExpression =
  ws* "." list:listExpression {
    return list;
  }

listExpression =
  ws* "[" items:listExpressionItem* ws* "]" ws* {
    return items;
  }

listExpressionItem =
  ws* expr:expression ws* ","? {
    return expr;
  }

subExpression =
  ws* "." ws* sub:expression ws* {
    return sub;
  }