LogQL linefilters bug

bug.go

package main

import (
	"fmt"

	"github.com/grafana/loki/pkg/logql/syntax"
)

func main() {
	q := `{app="loki"}!= "foo" or "bar"` // with single linefilters
	expr, err := syntax.ParseLogSelector(q, true)
	if err != nil {
		panic(err)
	}
	fmt.Printf("query=%v\nparsed=%v\n", q, expr.String())
	fmt.Println("---------------------")
	q2 := `{app="loki"}!= "test" != "foo" or "bar"` // with chain of linefilters
	expr2, err := syntax.ParseLogSelector(q2, true)
	if err != nil {
		panic(err)
	}
	fmt.Printf("query=%v\nparsed=%v\n", q2, expr2.String())
}

// Output
// query={app="loki"}!= "foo" or "bar"
// parsed={app="loki"} != "foo" != "bar"
// ---------------------
// query={app="loki"}!= "test" != "foo" or "bar"
// parsed={app="loki"} != "test" != "bar"

// note `foo` is missing on the second query.