TableFor1
Related Docs:
object TableFor1
| package prop
Applies the passed property check function to each row of this TableFor1.
Applies the passed property check function to each row of this TableFor1.
If the property checks for all rows succeed (the property check function returns normally when passed
the data for each row), this apply method returns normally. If the property check function
completes abruptly with an exception for any row, this apply method wraps that exception
in a TableDrivenPropertyCheckFailedException and completes abruptly with that exception. Once
the property check function throws an exception for a row, this apply method will complete
abruptly immediately and subsequent rows will not be checked against the function.
the property check function to apply to each row of this TableFor1
Selects a row of data by its index.
Selects a row of data by its index.
a string name for the lone column of this table
The number of rows of data in the table.
The number of rows of data in the table. (This does not include the heading tuple)
Creates a new Builder for TableFor1s.
Creates a new Builder for TableFor1s.
(Changed in version 2.9.0) The behavior of scanRight has changed. The previous behavior can be reproduced with scanRight.reverse.
A string representation of this object, which includes the heading strings as well as the rows of data.
A string representation of this object, which includes the heading strings as well as the rows of data.
(Changed in version 2.9.0) transpose throws an IllegalArgumentException if collections are not uniformly sized.
A table with 1 column.
For an overview of using tables, see the documentation for trait TableDrivenPropertyChecks.
This table is a sequence of objects, where each object represents one row of the (one-column) table. This table also carries with it a heading tuple that gives a string name to the lone column of the table.
A handy way to create a
TableFor1is via anapplyfactory method in theTablesingleton object provided by theTablestrait. Here's an example:val examples = Table( "a", 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 )Because you supplied a list of non-tuple objects, the type you'll get back will be a
TableFor1.The table provides an
applymethod that takes a function with a parameter list that matches the type of the objects contained in this table. Theapplymethod will invoke the function with the object in each row passed as the lone argument, in ascending order by index. (I.e., the zeroth object is checked first, then the object with index 1, then index 2, and so on until all the rows have been checked (or until a failure occurs). The function represents a property of the code under test that should succeed for every row of the table. If the function returns normally, that indicates the property check succeeded for that row. If the function completes abruptly with an exception, that indicates the property check failed and theapplymethod will complete abruptly with aTableDrivenPropertyCheckFailedExceptionthat wraps the exception thrown by the supplied property function.The usual way you'd invoke the
applymethod that checks a property is via aforAllmethod provided by traitTableDrivenPropertyChecks. TheforAllmethod takes aTableFor1as its first argument, then in a curried argument list takes the property check function. It invokesapplyon theTableFor1, passing in the property check function. Here's an example:forAll (examples) { (a) => a should equal (a * 1) }Because
TableFor1is aSeq[(A)], you can use it as aSeq. For example, here's how you could get a sequence ofOutcomes for each row of the table, indicating whether a property check succeeded or failed on each row of the table:for (row <- examples) yield { outcomeOf { row._1 should not equal (7) } }Note: the
outcomeOfmethod, contained in theOutcomeOftrait, will execute the supplied code (a by-name parameter) and transform it to anOutcome. If no exception is thrown by the code,outcomeOfwill result in aSucceeded, indicating the "property check" succeeded. If the supplied code completes abruptly in an exception that would normally cause a test to fail,outcomeOfwill result in in aFailedinstance containing that exception. For example, the previous for expression would give you:Vector(Succeeded, Succeeded, Succeeded, Succeeded, Succeeded, Succeeded, Succeeded, Failed(org.scalatest.TestFailedException: 7 equaled 7), Succeeded, Succeeded)This shows that all the property checks succeeded, except for the one at index 7.
One other way to use a
TableFor1is to test subsequent return values of a stateful function. Imagine, for example, you had an object namedFiboGenwhosenextmethod returned the next fibonacci number, where next means the next number in the series following the number previously returned bynext. So the first timenextwas called, it would return 0. The next time it was called it would return 1. Then 1. Then 2. Then 3, and so on.FiboGenwould need to be stateful, because it has to remember where it is in the series. In such a situation, you could create aTableFor1(a table with one column, which you could alternatively think of as one row), in which each row represents the next value you expect.val first14FiboNums = Table("n", 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233)Then in your
forAllsimply call the function and compare it with the expected return value, like this:forAll (first14FiboNums) { n => FiboGen.next should equal (n) }