package read

// This file contains some tools that are used for writing tests.

import (
	"fmt"
	"runtime"
	"testing"
)

func assertEqual(t *testing.T, expected interface{}, actual interface{}) {
	if expected != actual {
		switch expected.(type) {
		case rune:
			t.Errorf(
				"Unexpected value at %s:\nexpected: %q\nactual: %q",
				callerFilepos(1), expected, actual)
		default:
			t.Errorf(
				"Unexpected value at %s:\nexpected: %v\nactual: %v",
				callerFilepos(1), expected, actual)
		}
	}
}

func callerFilepos(depth int) string {
	// No error handling, because we call this method ourselves with safe depth values.
	_, file, line, _ := runtime.Caller(depth + 1)
	return fmt.Sprintf("%s:%d", file, line)
}

func assertPanic(t *testing.T, code func(), expected string) {
	defer func() {
		if r := recover(); r != nil {
			if expected != r.(string) {
				t.Errorf(
					"Code did panic, but unexpected panic message received:\nexpected: %q\nactual: %q",
					expected, r)
			}
		} else {
			t.Errorf("Function did not panic (expected panic message: %s)", expected)
		}
	}()
	code()
}

func assertBuffer(t *testing.T, name string, r *Buffer, code func(), capacity, start, length int) {
	code()
	if capacity != r.cap {
		t.Errorf("[%s] Unexpected buffer cap (expected %d, got %d)", name, capacity, r.cap)
	}
	if start != r.start {
		t.Errorf("[%s] Unexpected data starting point (expected %d, got %d)", name, start, r.start)
	}
	if length != r.len {
		t.Errorf("[%s] Unexpected buffer len (expected %d, got %d)", name, length, r.len)
	}
}