The source code schema for the Windows Installer XML Toolset Lux Extension. Test mutations let you author unit tests with different expected results. The mutation id is passed as the value of the WIXLUX_RUNNING_MUTATION property. Your custom action, typically in an '#ifdef DEBUG' block, can retrieve the WIXLUX_RUNNING_MUTATION property and hard-code different behavior based on the mutation. To author test mutations, use the Mutation element with UnitTest elements as children. Child UnitTest elements are validated when the parent mutation is being executed. Value of the WIXLUX_RUNNING_MUTATION property set by the mutation. Describes a unit test to be executed against a particular custom action, resulting in a particular property value. Single-value properties, multi-value properties, and name/value-pair properties can all be tested declaratively. Child UnitTest elements are used to test multi-value properties. Note that Property and ValueDelimiter or NameValueDelimiter must be specified in the parent element. Identifier of the unit test. If you omit this attribute, a stable identifier is generated for you. Identifier of the custom action to be tested. Name of the property set by the custom action. The operator to apply to the property and value. Default is "equal." (Default) Compares Property to Value and succeeds if they are equal. Compares Property to Value and succeeds if they are NOT equal. Compares Property to Value and succeeds if they are equal (ignoring case). Compares Property to Value and succeeds if they are NOT equal (ignoring case). The value to compare to the property. One character that is used to separate values in a multi-value property. One character that is used to separate values in a name/value-pair multi-value property. A formatted string that evaluates to either an integer index into a multi-value property or a string name of a name/value-pair multi-value property. Conditions for a unit test. An expression that must evaluate to true to succeed. Cannot be specified if Property is specified. Identifies a unit test to be linked into a project. Identifier of the unit test to be included.