// Copyright © 2010-12 Qtrac Ltd.

//

// This program or package and any associated files are licensed under the

// Apache License, Version 2.0 (the "License"); you may not use these files

// except in compliance with the License. You can get a copy of the License

// at: http://www.apache.org/licenses/LICENSE-2.0.

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

package stack_test

import (

"github.com/henrylee2cn/algorithm/evaler/stack"

"testing"

)

func TestStack(t *testing.T) {

count := 1

var aStack stack.Stack

assertTrue(t, aStack.Len() == 0, "expected empty Stack", count) // 1

count++

assertTrue(t, aStack.Cap() == 0, "expected empty Stack", count) // 2

count++

assertTrue(t, aStack.IsEmpty(), "expected empty Stack", count) // 3

count++

value, err := aStack.Pop()

assertTrue(t, value == nil, "expected nil value", count) // 4

count++

assertTrue(t, err != nil, "expected error", count) // 5

count++

value1, err := aStack.Top()

assertTrue(t, value1 == nil, "expected nil value", count) // 6

count++

assertTrue(t, err != nil, "expected error", count) // 7

count++

aStack.Push(1)

aStack.Push(2)

aStack.Push("three")

assertTrue(t, aStack.Len() == 3, "expected nonempty Stack", count) // 8

count++

assertTrue(t, aStack.IsEmpty() == false, "expected nonempty Stack",

count) // 9

count++

value2, err := aStack.Pop()

assertEqualString(t, value2.(string), "three", "unexpected text",

count) // 10

count++

assertTrue(t, err == nil, "no error expected", count) // 11

count++

value3, err := aStack.Top()

assertTrue(t, value3 == 2, "unexpected number", count) // 12

count++

assertTrue(t, err == nil, "no error expected", count) // 13

count++

aStack.Pop()

assertTrue(t, aStack.Len() == 1, "expected nonempty Stack", count) //14

count++

assertTrue(t, aStack.IsEmpty() == false, "expected nonempty Stack",

count) // 15

count++

value4, err := aStack.Pop()

assertTrue(t, value4 == 1, "unexpected number", count) // 16

count++

assertTrue(t, err == nil, "no error expected", count) // 17

count++

assertTrue(t, aStack.Len() == 0, "expected empty Stack", count) // 18

count++

assertTrue(t, aStack.IsEmpty(), "expected empty Stack", count) // 19

count++

}

// assertTrue() calls testing.T.Error() with the given message if the

// condition is false.

func assertTrue(t *testing.T, condition bool, message string, id int) {

if !condition {

t.Errorf("#%d: %s", id, message)

}

}

// assertEqualString() calls testing.T.Error() with the given message if

// the given strings are not equal.

func assertEqualString(t *testing.T, a, b string, message string, id int) {

if a != b {

t.Errorf("#%d: %s \"%s\" !=\n\"%s\"", id, message, a, b)

}

}