public void WhenReadingEndOfSource_ExpectMinusOne()
{
// Given that the text source has been initialized with an string
// When Read is called
// Then -1 is returned
var sut = new StringTextSource("");
var read = sut.Read();
Assert.Equal(-1, read);
}
public void WhenReadWithEmptyBuffer_ExpectArgumentNullException()
{
// Given that the text source has been initialized with a non-empty string
// When Read is called with a buffer that is a null reference
// Then an ArgumentNullException is thrown
var sut = new StringTextSource(Sentence);
int read;
Assert.Throws <ArgumentNullException>(() => read = sut.Read(null, 0, Sentence.Length));
}
public void WhenReadWithCountBeyondBufferLength_ExpectArgumentOutOfRangeException()
{
// Given that the text source has been initialized with a non-empty string
// When Read is called with a count that exceeds the buffer length
// Then an ArgumentOutOfRangeException is thrown
var sut = new StringTextSource(Sentence);
var buffer = new char[Sentence.Length];
int read;
Assert.Throws <ArgumentOutOfRangeException>(() => read = sut.Read(buffer, 0, buffer.Length + 1));
}
public void WhenReadWithNegativeOffset_ExpectArgumentOutOfRangeException()
{
// Given that the text source has been initialized with a non-empty string
// When Read is called with a negative offset
// Then an ArgumentOutOfRangeException is thrown
var sut = new StringTextSource(Sentence);
var buffer = new char[Sentence.Length];
int read;
Assert.Throws <ArgumentOutOfRangeException>(() => read = sut.Read(buffer, -1, buffer.Length));
}
public void SeekWithoutRecording()
{
// Given that there is a text source
// and the text length is 10
// When reading 1 character
// and seeking to offset 0
// Then an exception is thrown
using (var sut = new StringTextSource("1234567890"))
{
sut.Read(new char[2], 0, 2);
Assert.Throws <ArgumentOutOfRangeException>(() => sut.Seek(0));
}
}
public void WhenRead_ExpectCharacterIsReturnedAndConsumed()
{
// Given that there is text to be read
// When Read is called
// Then the next available character is returned
// And the character is consumed
using (var sut = new StringTextSource("abc"))
{
var read = (char)sut.Read();
Assert.Equal('a', read);
// Verify behavior by peeking at the next character
var peek = (char)sut.Peek();
Assert.NotEqual('a', peek);
}
}
public void WhenReadWithBuffer_ExpectTextIsReturnedAndConsumed()
{
// Given that there is text to be read
// When Read is called
// Then the buffer contains the text
// And the text is consumed
using (var sut = new StringTextSource(Sentence))
{
var buffer = new char[Sentence.Length];
var len = sut.Read(buffer, 0, buffer.Length);
Assert.Equal(buffer.Length, len);
Assert.Equal(Sentence.ToCharArray(), buffer);
// Verify behavior by peeking at the next character
Assert.Equal(-1, sut.Peek());
}
}
public void WhenReadWithBufferBiggerThanTextSource_ExpectResultLessThanBufferSize()
{
// Given that there is text to be read
// When Read is called with a buffer
// And the buffer length is larger than the length of the text
// Then the buffer contains the text
// And the returned length is less than the length of the buffer
// And the text is consumed
using (var sut = new StringTextSource(Sentence))
{
var buffer = new char[Sentence.Length * 2];
var len = sut.Read(buffer, 0, buffer.Length);
Assert.Equal(Sentence.Length, len);
Assert.Equal(Sentence.ToCharArray(), buffer.Take(len));
// Verify behavior by peeking at the next character
Assert.Equal(-1, sut.Peek());
}
}
