promqltests.go

package main

import (
	"fmt"
	"os"

	"github.com/prometheus/prometheus/promql/parser"
)

func main() {
	if len(os.Args) != 2 {
		fmt.Printf("wat?\n")
		return
	}
	p := parser.NewParser(os.Args[1])
	expr, err := p.ParseExpr()
	if err != nil {
		fmt.Printf("Error: %s\n", err.Error())
		return
	}
	fmt.Println(visit(expr))
}

func visit(e parser.Expr) string {
	switch el := e.(type) {
	case *parser.NumberLiteral:
		return fmt.Sprintf("NumberLiteral val=%g", el.Val)
	case *parser.BinaryExpr:
		return fmt.Sprintf("BinaryExpr op=%s lhs=(%s) rhs=(%s)",
			parser.ItemTypeStr[el.Op], visit(el.LHS), visit(el.RHS))
	default:
		return fmt.Sprintf("%#v", el)
	}
}