Class ConstraintExpression

ConstraintExpression represents a compound constraint in the process of being constructed from a series of syntactic elements.

Individual elements are appended to the expression as they are reorganized. When a constraint is appended, it is returned as the value of the operation so that modifiers may be applied. However, any partially built expression is attached to the constraint for later resolution. When an operator is appended, the partial expression is returned. If it's a self-resolving operator, then a ResolvableConstraintExpression is returned.

Inheritance

object

ConstraintExpression

ItemsConstraintExpression

ResolvableConstraintExpression

Inherited Members

object.GetType()

object.MemberwiseClone()

object.Equals(object)

object.Equals(object, object)

object.ReferenceEquals(object, object)

object.GetHashCode()

Namespace: NUnit.Framework.Constraints

Assembly: nunit.framework.dll

Syntax

public class ConstraintExpression

Constructors

ConstraintExpression()

Initializes a new instance of the ConstraintExpression class.

Declaration

public ConstraintExpression()

ConstraintExpression(ConstraintBuilder)

Initializes a new instance of the ConstraintExpression class passing in a ConstraintBuilder, which may be pre-populated.

Declaration

public ConstraintExpression(ConstraintBuilder builder)

Parameters

Type	Name	Description
ConstraintBuilder	builder	The builder.

Fields

builder

The ConstraintBuilder holding the elements recognized so far

Declaration

protected readonly ConstraintBuilder builder

Field Value

Type	Description
ConstraintBuilder

Properties

All

Returns a ConstraintExpression, which will apply the following constraint to all members of a collection, succeeding if all of them succeed.

Declaration

public ConstraintExpression All { get; }

Property Value

Type	Description
ConstraintExpression

Count

Returns a new ConstraintExpression, which will apply the following constraint to the Count property of the object being tested.

Declaration

public ResolvableConstraintExpression Count { get; }

Property Value

Type	Description
ResolvableConstraintExpression

Default

Returns a constraint that tests for default value

Declaration

public DefaultConstraint Default { get; }

Property Value

Type	Description
DefaultConstraint

Empty

Returns a constraint that tests for empty

Declaration

public EmptyConstraint Empty { get; }

Property Value

Type	Description
EmptyConstraint

Exist

Returns a constraint that succeeds if the value is a file or directory and it exists.

Declaration

public Constraint Exist { get; }

Property Value

Type	Description
Constraint

False

Returns a constraint that tests for False

Declaration

public FalseConstraint False { get; }

Property Value

Type	Description
FalseConstraint

InnerException

Returns a new ConstraintExpression, which will apply the following constraint to the InnerException property of the object being tested.

Declaration

public ResolvableConstraintExpression InnerException { get; }

Property Value

Type	Description
ResolvableConstraintExpression

Length

Returns a new ConstraintExpression, which will apply the following constraint to the Length property of the object being tested.

Declaration

public ResolvableConstraintExpression Length { get; }

Property Value

Type	Description
ResolvableConstraintExpression

Message

Returns a new ConstraintExpression, which will apply the following constraint to the Message property of the object being tested.

Declaration

public ResolvableConstraintExpression Message { get; }

Property Value

Type	Description
ResolvableConstraintExpression

NaN

Returns a constraint that tests for NaN

Declaration

public NaNConstraint NaN { get; }

Property Value

Type	Description
NaNConstraint

Negative

Returns a constraint that tests for a negative value

Declaration

public LessThanConstraint Negative { get; }

Property Value

Type	Description
LessThanConstraint

No

Returns a ConstraintExpression that negates any following constraint.

Declaration

public ConstraintExpression No { get; }

Property Value

Type	Description
ConstraintExpression

None

Returns a ConstraintExpression, which will apply the following constraint to all members of a collection, succeeding if all of them fail.

Declaration

public ConstraintExpression None { get; }

Property Value

Type	Description
ConstraintExpression

Not

Returns a ConstraintExpression that negates any following constraint.

Declaration

public ConstraintExpression Not { get; }

Property Value

Type	Description
ConstraintExpression

Null

Returns a constraint that tests for null

Declaration

public NullConstraint Null { get; }

Property Value

Type	Description
NullConstraint

One

Returns a ItemsConstraintExpression, which will apply the following constraint to a collection of length one, succeeding only if exactly one of them succeeds.

Declaration

public ItemsConstraintExpression One { get; }

Property Value

Type	Description
ItemsConstraintExpression

Ordered

Returns a constraint that tests whether a collection is ordered

Declaration

public CollectionOrderedConstraint Ordered { get; }

Property Value

Type	Description
CollectionOrderedConstraint

Positive

Returns a constraint that tests for a positive value

Declaration

public GreaterThanConstraint Positive { get; }

Property Value

Type	Description
GreaterThanConstraint

Some

Returns a ConstraintExpression, which will apply the following constraint to all members of a collection, succeeding if at least one of them succeeds.

Declaration

public ConstraintExpression Some { get; }

Property Value

Type	Description
ConstraintExpression

True

Returns a constraint that tests for True

Declaration

public TrueConstraint True { get; }

Property Value

Type	Description
TrueConstraint

Unique

Returns a constraint that tests whether a collection contains all unique items.

Declaration

public UniqueItemsConstraint Unique { get; }

Property Value

Type	Description
UniqueItemsConstraint

WhiteSpace

Returns a constraint that tests for white-space

Declaration

public WhiteSpaceConstraint WhiteSpace { get; }

Property Value

Type	Description
WhiteSpaceConstraint

With

With is currently a NOP - reserved for future use.

Declaration

public ConstraintExpression With { get; }

Property Value

Type	Description
ConstraintExpression

XmlSerializable

Returns a constraint that tests whether an object graph is serializable in XML format.

Declaration

public XmlSerializableConstraint XmlSerializable { get; }

Property Value

Type	Description
XmlSerializableConstraint

Zero

Returns a constraint that tests if item is equal to zero

Declaration

public EqualConstraint Zero { get; }

Property Value

Type	Description
EqualConstraint

Methods

AnyOf(ICollection)

Returns a constraint that tests if an item is equal to any of expected values

Declaration

public AnyOfConstraint AnyOf(ICollection expected)

Parameters

Type	Name	Description
ICollection	expected	Expected values

Returns

Type	Description
AnyOfConstraint

AnyOf(params object?[]?)

Returns a constraint that tests if an item is equal to any of parameters

Declaration

public AnyOfConstraint AnyOf(params object?[]? expected)

Parameters

Type	Name	Description
object[]	expected	Expected values

Returns

Type	Description
AnyOfConstraint

Append(Constraint)

Appends a constraint to the expression and returns that constraint, which is associated with the current state of the expression being built. Note that the constraint is not reduced at this time. For example, if there is a NotOperator on the stack we don't reduce and return a NotConstraint. The original constraint must be returned because it may support modifiers that are yet to be applied.

Declaration

public Constraint Append(Constraint constraint)

Parameters

Type	Name	Description
Constraint	constraint

Returns

Type	Description
Constraint

Append(ConstraintOperator)

Appends an operator to the expression and returns the resulting expression itself.

Declaration

public ConstraintExpression Append(ConstraintOperator op)

Parameters

Type	Name	Description
ConstraintOperator	op

Returns

Type	Description
ConstraintExpression

Append(SelfResolvingOperator)

Appends a self-resolving operator to the expression and returns a new ResolvableConstraintExpression.

Declaration

public ResolvableConstraintExpression Append(SelfResolvingOperator op)

Parameters

Type	Name	Description
SelfResolvingOperator	op

Returns

Type	Description
ResolvableConstraintExpression

Append<T>(T)

Appends a constraint to the expression and returns that constraint, which is associated with the current state of the expression being built. Note that the constraint is not reduced at this time. For example, if there is a NotOperator on the stack we don't reduce and return a NotConstraint. The original constraint must be returned because it may support modifiers that are yet to be applied.

Declaration

public T Append<T>(T constraint) where T : Constraint

Parameters

Type	Name	Description
T	constraint

Returns

Type	Description
T

Type Parameters

Name	Description
T

AssignableFrom(Type)

Returns a constraint that tests whether the actual value is assignable from the type supplied as an argument.

Declaration

public AssignableFromConstraint AssignableFrom(Type expectedType)

Parameters

Type	Name	Description
Type	expectedType

Returns

Type	Description
AssignableFromConstraint

AssignableFrom<TExpected>()

Returns a constraint that tests whether the actual value is assignable from the type supplied as an argument.

Declaration

public AssignableFromConstraint AssignableFrom<TExpected>()

Returns

Type	Description
AssignableFromConstraint

Type Parameters

Name	Description
TExpected

AssignableTo(Type)

Returns a constraint that tests whether the actual value is assignable from the type supplied as an argument.

Declaration

public AssignableToConstraint AssignableTo(Type expectedType)

Parameters

Type	Name	Description
Type	expectedType

Returns

Type	Description
AssignableToConstraint

AssignableTo<TExpected>()

Returns a constraint that tests whether the actual value is assignable from the type supplied as an argument.

Declaration

public AssignableToConstraint AssignableTo<TExpected>()

Returns

Type	Description
AssignableToConstraint

Type Parameters

Name	Description
TExpected

AtLeast(object)

Returns a constraint that tests whether the actual value is greater than or equal to the supplied argument

Declaration

public GreaterThanOrEqualConstraint AtLeast(object expected)

Parameters

Type	Name	Description
object	expected

Returns

Type	Description
GreaterThanOrEqualConstraint

AtMost(object)

Returns a constraint that tests whether the actual value is less than or equal to the supplied argument

Declaration

public LessThanOrEqualConstraint AtMost(object expected)

Parameters

Type	Name	Description
object	expected

Returns

Type	Description
LessThanOrEqualConstraint

Attribute(Type)

Returns a new AttributeConstraint checking for the presence of a particular attribute on an object.

Declaration

public ResolvableConstraintExpression Attribute(Type expectedType)

Parameters

Type	Name	Description
Type	expectedType

Returns

Type	Description
ResolvableConstraintExpression

Attribute<TExpected>()

Returns a new AttributeConstraint checking for the presence of a particular attribute on an object.

Declaration

public ResolvableConstraintExpression Attribute<TExpected>()

Returns

Type	Description
ResolvableConstraintExpression

Type Parameters

Name	Description
TExpected

Contain(object?)

Returns a new SomeItemsConstraint checking for the presence of a particular object in the collection.

Declaration

public SomeItemsConstraint Contain(object? expected)

Parameters

Type	Name	Description
object	expected

Returns

Type	Description
SomeItemsConstraint

Contain(string?)

Returns a new ContainsConstraint. This constraint will, in turn, make use of the appropriate second-level constraint, depending on the type of the actual argument. This overload is only used if the item sought is a string, since any other type implies that we are looking for a collection member.

Declaration

public ContainsConstraint Contain(string? expected)

Parameters

Type	Name	Description
string	expected

Returns

Type	Description
ContainsConstraint

ContainKey(object)

Returns a new DictionaryContainsKeyConstraint checking for the presence of a particular key in the Dictionary key collection.

Declaration

public DictionaryContainsKeyConstraint ContainKey(object expected)

Parameters

Type	Name	Description
object	expected	The key to be matched in the Dictionary key collection

Returns

Type	Description
DictionaryContainsKeyConstraint

ContainValue(object?)

Returns a new DictionaryContainsValueConstraint checking for the presence of a particular value in the Dictionary value collection.

Declaration

public DictionaryContainsValueConstraint ContainValue(object? expected)

Parameters

Type	Name	Description
object	expected	The value to be matched in the Dictionary value collection

Returns

Type	Description
DictionaryContainsValueConstraint

Contains(object?)

Returns a new SomeItemsConstraint checking for the presence of a particular object in the collection.

To search for a substring instead of a collection element, use the Contains(string?) overload.

Declaration

public SomeItemsConstraint Contains(object? expected)

Parameters

Type	Name	Description
object	expected

Returns

Type	Description
SomeItemsConstraint

Contains(string?)

Returns a new ContainsConstraint. This constraint will, in turn, make use of the appropriate second-level constraint, depending on the type of the actual argument.

To search for a collection element instead of a substring, use the Contains(object?) overload.

Declaration

public ContainsConstraint Contains(string? expected)

Parameters

Type	Name	Description
string	expected

Returns

Type	Description
ContainsConstraint

EndWith(string)

Returns a constraint that succeeds if the actual value ends with the substring supplied as an argument.

Declaration

public EndsWithConstraint EndWith(string expected)

Parameters

Type	Name	Description
string	expected

Returns

Type	Description
EndsWithConstraint

EndsWith(string)

Returns a constraint that succeeds if the actual value ends with the substring supplied as an argument.

Declaration

public EndsWithConstraint EndsWith(string expected)

Parameters

Type	Name	Description
string	expected

Returns

Type	Description
EndsWithConstraint

EqualTo(object?)

Returns a constraint that tests two items for equality

Declaration

public EqualConstraint EqualTo(object? expected)

Parameters

Type	Name	Description
object	expected

Returns

Type	Description
EqualConstraint

EquivalentTo(IEnumerable)

Returns a constraint that tests whether the actual value is a collection containing the same elements as the collection supplied as an argument.

Declaration

public CollectionEquivalentConstraint EquivalentTo(IEnumerable expected)

Parameters

Type	Name	Description
IEnumerable	expected

Returns

Type	Description
CollectionEquivalentConstraint

Exactly(int)

Returns a ConstraintExpression, which will apply the following constraint to all members of a collection, succeeding only if a specified number of them succeed.

Declaration

public ItemsConstraintExpression Exactly(int expectedCount)

Parameters

Type	Name	Description
int	expectedCount

Returns

Type	Description
ItemsConstraintExpression

GreaterThan(object)

Returns a constraint that tests whether the actual value is greater than the supplied argument

Declaration

public GreaterThanConstraint GreaterThan(object expected)

Parameters

Type	Name	Description
object	expected

Returns

Type	Description
GreaterThanConstraint

GreaterThanOrEqualTo(object)

Returns a constraint that tests whether the actual value is greater than or equal to the supplied argument

Declaration

public GreaterThanOrEqualConstraint GreaterThanOrEqualTo(object expected)

Parameters

Type	Name	Description
object	expected

Returns

Type	Description
GreaterThanOrEqualConstraint

InRange(object, object)

Returns a constraint that tests whether the actual value falls inclusively within a specified range.

Declaration

public RangeConstraint InRange(object from, object to)

Parameters

Type	Name	Description
object	from	Inclusive beginning of the range.
object	to	Inclusive end of the range.

Returns

Type	Description
RangeConstraint

InstanceOf(Type)

Returns a constraint that tests whether the actual value is of the type supplied as an argument or a derived type.

Declaration

public InstanceOfTypeConstraint InstanceOf(Type expectedType)

Parameters

Type	Name	Description
Type	expectedType

Returns

Type	Description
InstanceOfTypeConstraint

InstanceOf<TExpected>()

Returns a constraint that tests whether the actual value is of the type supplied as an argument or a derived type.

Declaration

public InstanceOfTypeConstraint InstanceOf<TExpected>()

Returns

Type	Description
InstanceOfTypeConstraint

Type Parameters

Name	Description
TExpected

ItemAt(params object[])

Returns a new IndexerConstraintExpression, which will apply any following constraint to that indexer value.

Declaration

public ConstraintExpression ItemAt(params object[] indexArgs)

Parameters

Type	Name	Description
object[]	indexArgs	Index accessor values.

Returns

Type	Description
ConstraintExpression

LessThan(object)

Returns a constraint that tests whether the actual value is less than the supplied argument

Declaration

public LessThanConstraint LessThan(object expected)

Parameters

Type	Name	Description
object	expected

Returns

Type	Description
LessThanConstraint

LessThanOrEqualTo(object)

Returns a constraint that tests whether the actual value is less than or equal to the supplied argument

Declaration

public LessThanOrEqualConstraint LessThanOrEqualTo(object expected)

Parameters

Type	Name	Description
object	expected

Returns

Type	Description
LessThanOrEqualConstraint

Match(string)

Returns a constraint that succeeds if the actual value matches the regular expression supplied as an argument.

Declaration

public RegexConstraint Match(string pattern)

Parameters

Type	Name	Description
string	pattern

Returns

Type	Description
RegexConstraint

Match(Regex)

Returns a constraint that succeeds if the actual value matches the regular expression supplied as an argument.

Declaration

public RegexConstraint Match(Regex regex)

Parameters

Type	Name	Description
Regex	regex

Returns

Type	Description
RegexConstraint

Matches(IResolveConstraint)

Returns the constraint provided as an argument - used to allow custom custom constraints to easily participate in the syntax.

Declaration

public Constraint Matches(IResolveConstraint constraint)

Parameters

Type	Name	Description
IResolveConstraint	constraint

Returns

Type	Description
Constraint

Matches(string)

Returns a constraint that succeeds if the actual value matches the regular expression supplied as an argument.

Declaration

public RegexConstraint Matches(string pattern)

Parameters

Type	Name	Description
string	pattern

Returns

Type	Description
RegexConstraint

Matches(Regex)

Returns a constraint that succeeds if the actual value matches the regular expression supplied as an argument.

Declaration

public RegexConstraint Matches(Regex regex)

Parameters

Type	Name	Description
Regex	regex

Returns

Type	Description
RegexConstraint

Matches<TActual>(Predicate<TActual>)

Returns the constraint provided as an argument - used to allow custom custom constraints to easily participate in the syntax.

Declaration

public Constraint Matches<TActual>(Predicate<TActual> predicate)

Parameters

Type	Name	Description
Predicate<TActual>	predicate

Returns

Type	Description
Constraint

Type Parameters

Name	Description
TActual

Member(object?)

Returns a new SomeItemsConstraint checking for the presence of a particular object in the collection.

Declaration

public SomeItemsConstraint Member(object? expected)

Parameters

Type	Name	Description
object	expected

Returns

Type	Description
SomeItemsConstraint

Property(string)

Returns a new PropertyConstraintExpression, which will either test for the existence of the named property on the object being tested or apply any following constraint to that property.

Declaration

public ResolvableConstraintExpression Property(string name)

Parameters

Type	Name	Description
string	name

Returns

Type	Description
ResolvableConstraintExpression

SameAs(object?)

Returns a constraint that tests that two references are the same object

Declaration

public SameAsConstraint SameAs(object? expected)

Parameters

Type	Name	Description
object	expected

Returns

Type	Description
SameAsConstraint

SamePath(string)

Returns a constraint that tests whether the path provided is the same as an expected path after canonicalization.

Declaration

public SamePathConstraint SamePath(string expected)

Parameters

Type	Name	Description
string	expected

Returns

Type	Description
SamePathConstraint

SamePathOrUnder(string)

Returns a constraint that tests whether the path provided is the same path or under an expected path after canonicalization.

Declaration

public SamePathOrUnderConstraint SamePathOrUnder(string expected)

Parameters

Type	Name	Description
string	expected

Returns

Type	Description
SamePathOrUnderConstraint

StartWith(string)

Returns a constraint that succeeds if the actual value starts with the substring supplied as an argument.

Declaration

public StartsWithConstraint StartWith(string expected)

Parameters

Type	Name	Description
string	expected

Returns

Type	Description
StartsWithConstraint

StartsWith(string)

Returns a constraint that succeeds if the actual value starts with the substring supplied as an argument.

Declaration

public StartsWithConstraint StartsWith(string expected)

Parameters

Type	Name	Description
string	expected

Returns

Type	Description
StartsWithConstraint

SubPathOf(string)

Returns a constraint that tests whether the path provided is the a subpath of the expected path after canonicalization.

Declaration

public SubPathConstraint SubPathOf(string expected)

Parameters

Type	Name	Description
string	expected

Returns

Type	Description
SubPathConstraint

SubsetOf(IEnumerable)

Returns a constraint that tests whether the actual value is a subset of the collection supplied as an argument.

Declaration

public CollectionSubsetConstraint SubsetOf(IEnumerable expected)

Parameters

Type	Name	Description
IEnumerable	expected

Returns

Type	Description
CollectionSubsetConstraint

SupersetOf(IEnumerable)

Returns a constraint that tests whether the actual value is a superset of the collection supplied as an argument.

Declaration

public CollectionSupersetConstraint SupersetOf(IEnumerable expected)

Parameters

Type	Name	Description
IEnumerable	expected

Returns

Type	Description
CollectionSupersetConstraint

ToString()

Returns a string representation of the expression as it currently stands. This should only be used for testing, since it has the side-effect of resolving the expression.

Declaration

public override string ToString()

Returns

Type	Description
string

Overrides

object.ToString()

TypeOf(Type)

Returns a constraint that tests whether the actual value is of the exact type supplied as an argument.

Declaration

public ExactTypeConstraint TypeOf(Type expectedType)

Parameters

Type	Name	Description
Type	expectedType

Returns

Type	Description
ExactTypeConstraint

TypeOf<TExpected>()

Returns a constraint that tests whether the actual value is of the exact type supplied as an argument.

Declaration

public ExactTypeConstraint TypeOf<TExpected>()

Returns

Type	Description
ExactTypeConstraint

Type Parameters

Name	Description
TExpected