goparselib/parse_test.go at master · timbeurskens/goparselib · GitHub

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package goparselib

import "testing"

const (
	example1 = "25x"
	example2 = "(20+10)x"
	example3 = "((1844+2546)+(3+(4+5)))x"

	counterexample1 = "(20+10x"
	counterexample2 = "20+10x"
	counterexample3 = "(20)x"
)

var (
	// start = CTerminal("\\`")
	end      = CTerminal("x")
	number   = CTerminal("[0-9]+")
	operator = CTerminal("\\+")
	rclose   = CTerminal("\\)")
	lopen    = CTerminal("\\(")

	expression = new(Symbol)
	root       = new(Symbol)
)

func init() {
	*expression = Union{number, Concat{lopen, R(expression), operator, R(expression), rclose}}
	*root = Concat{R(expression), end}
}

func TestLang(t *testing.T) {
	_, err1 := ParseString(example1, R(root))
	if err1 != nil {
		t.Error(err1)
	}
	_, err2 := ParseString(example2, R(root))
	if err2 != nil {
		t.Error(err2)
	}
	node, err3 := ParseString(example3, R(root))
	if err3 != nil {
		t.Error(err3)
	}

	_, nok1 := ParseString(counterexample1, R(root))
	if nok1 == nil {
		t.Fail()
	}
	t.Log(nok1)
	_, nok2 := ParseString(counterexample2, R(root))
	if nok2 == nil {
		t.Fail()
	}
	t.Log(nok2)
	_, nok3 := ParseString(counterexample3, R(root))
	if nok3 == nil {
		t.Fail()
	}
	t.Log(nok3)
	//node.Populate(example3)

	t.Log(node)
}