NUnit - StringConstraints

## String Constraints (NUnit 2.4)

String constraints perform tests that are specific to strings. Attempting to test a non-string value with a string constraint is an error and gives an exception.

The Text prefix is deprecated beginning with NUnit 2.5.1 and will be removed in NUnit 3.0.

### SubstringConstraint

#### Action

Tests for a substring.

#### Constructor

    SubstringConstraint(string expected)

#### Syntax

    Is.StringContaining(string expected)
    Contains.Substring(string expected)
    ContainsSubstring(string expected)
    Contains(string expected)
    [Obsolete] Text.Contains(string expected)
    [Obsolete] Text.DoesNotContain(string expected)

#### Modifiers

    ...IgnoreCase

#### Examples of Use

    string phrase = "Make your tests fail before passing!"

    Assert.That( phrase, Is.StringContaining( "tests fail" ) );
    Assert.That( phrase, Contains.Substring( "tests fail" ) );
    Assert.That( phrase, Is.Not.StringContaining( "tests pass" ) );
    Assert.That( phrase, Is.StringContaining( "make" ).IgnoreCase );
    Expect (phrase, Contains.Substring( "make" ).IgnoreCase );

#### Notes

1. ContainsSubstring and Contains may appear only in the body of a constraint expression or when the inherited syntax is used.
2. Contains is not actually a string constraint but is converted to one when a string is being tested.

### StartsWithConstraint

#### Action

Tests for an initial string.

#### Constructor

    StartsWithConstraint(string expected)

#### Syntax

    Is.StringStarting(string expected)
    StartsWith(string expected)
    [Obsolete] Text.StartsWith(string expected)
    [Obsolete] Text.DoesNotStartWith(string expected)

#### Modifiers

    ...IgnoreCase

#### Examples of Use

    string phrase = "Make your tests fail before passing!"

    Assert.That( phrase, Is.StringStarting( "Make" ) );
    Assert.That( phrase, Is.Not.StringStarting( "Break" ) );
    Assert.That( phrase, Has.Length.GreaterThan(10)
                    .And.Not.StartsWith( "Break" ) );
    Expect( phrase, StartsWith( "Make" ) );

#### Notes

1. StartsWith may appear only in the body of a constraint expression or when the inherited syntax is used.

### EndsWithConstraint

#### Action

Tests for an ending string.

#### Constructor

    EndsWithConstraint(string expected)

#### Syntax

    Is.StringEnding(string expected)
    EndsWith(string expected)
    [Obsolete] Text.EndsWith(string expected)
    [Obsolete] Text.DoesNotEndWith(string expected)

#### Modifiers

    ...IgnoreCase

#### Examples of Use

    string phrase = "Make your tests fail before passing!"

    Assert.That( phrase, Is.StringEnding( "!" ) );
    Assert.That( phrase, Is.StringEnding( "PASSING!" ).IgnoreCase );
    Expect( phrase, EndsWith( "!" ) );

#### Notes

1. EndsWith may appear only in the body of a constraint expression or when the inherited syntax is used.

### RegexConstraint

#### Action

Tests that a pattern is matched.

#### Constructor

    RegexConstraint(string pattern)

#### Syntax

    Is.StringMatching(string pattern)
    Matches(string pattern)
    [Obsolete] Text.Matches(string pattern)
    [Obsolete] Text.DoesNotMatch(string pattern)

#### Modifiers

    ...IgnoreCase

#### Examples of Use

    string phrase = "Make your tests fail before passing!"

    Assert.That( phrase, Is.StringMatching( "Make.*tests.*pass" ) );
    Assert.That( phrase, Is.Not.StringMatching( "your.*passing.*tests" ) );
    Assert.That( phrase, Has.Length.GreaterThan(10)
                    .And.Not.Matches( "your.*passing.*tests" ) );
    Expect( phrase, Matches( "Make.*pass" ) );

#### Notes

1. Matches may appear only in the body of a constraint expression or when the inherited syntax is used.