test_constraint( $type, $tests, [ $describer ] )

This subroutine accepts two arguments. The first should be a Specio type object. The second is hashref which can contain the keys "accept" and "reject". Each key should contain an arrayref of values which the type accepts or rejects.

The third argument is optional. This is a sub reference which will be called to generate a description of the value being tested. This defaults to calling this package's "describe" sub, but you can provide your own.

describe($value)

Given a value, this subroutine returns a string describing that value in a useful way for test output. It know about the various classes used for the variables exported by this package and will do something intelligent when such a variable.

builtins_tests( $GLOB, $GLOB_OVERLOAD, $GLOB_OVERLOAD_FH )

This subroutine returns a hashref containing test variables for all builtin types. The hashref has a form like this:

  {
      Bool => {
          accept => [
              $ZERO,
              $ONE,
              $BOOL_OVERLOAD_TRUE,
              $BOOL_OVERLOAD_FALSE,
              ...,
          ],
          reject => [
              $INT,
              $NEG_INT,
              $NUM,
              $NEG_NUM,
              ...,
              $OBJECT,
          ],
      },
      Maybe => {...},
  }

You need to pass in a glob, an object which overloads globification, and an object which overloads globification to return an open filehandle. See below for more details on how to create these things.

Variables

This module also exports many variables containing values which are useful for testing constraints. Note that references are always empty unless stated otherwise. You can import these variables individually or import all of them with the ":vars" import tag.

• $ZERO
• $ONE
• $INT

  An arbitrary positive integer.

• $NEG_INT

  An arbitrary negative integer.

• $NUM

  An arbitrary positive non-integer number.

• $NEG_NUM

  An arbitrary negative non-integer number.

• $EMPTY_STRING
• $STRING

  An arbitrary non-empty string.

• $NUM_IN_STRING

  An arbitrary string which contains a number.

• $INT_WITH_NL1

  An string containing an integer followed by a newline.

• $INT_WITH_NL2

  An string containing a newline followed by an integer.

• $SCALAR_REF
• $SCALAR_REF_REF

  A reference containing a reference to a scalar.

• $ARRAY_REF
• $HASH_REF
• $CODE_REF
• $GLOB_REF
• $FH

  An opened filehandle.

• $FH_OBJECT

  An opened IO::File object.

• $REGEX

  A regex created with "qr//".

• $REGEX_OBJ

  A regex created with "qr//" that was then blessed into class.

• $FAKE_REGEX

  A non-regex blessed into the "Regexp" class which Perl uses internally for "qr//" objects.

• $OBJECT

  An arbitrary object.

• $UNDEF
• $CLASS_NAME

  A string containing a loaded package name.

• $BOOL_OVERLOAD_TRUE

  An object which overloads boolification to return true.

• $BOOL_OVERLOAD_FALSE

  An object which overloads boolification to return false.

• $STR_OVERLOAD_EMPTY

  An object which overloads stringification to return an empty string.

• $STR_OVERLOAD_FULL

  An object which overloads stringification to return a non-empty string.

• $STR_OVERLOAD_CLASS_NAME

  An object which overloads stringification to return a loaded package name.

• $NUM_OVERLOAD_ZERO
• $NUM_OVERLOAD_ONE
• $NUM_OVERLOAD_NEG
• $NUM_OVERLOAD_DECIMAL
• $NUM_OVERLOAD_NEG_DECIMAL
• $CODE_OVERLOAD
• $SCALAR_OVERLOAD

  An object which overloads scalar dereferencing to return a non-empty string.

• $ARRAY_OVERLOAD

  An object which overloads array dereferencing to return a non-empty array.

• $HASH_OVERLOAD

  An object which overloads hash dereferencing to return a non-empty hash.

Globs and the _T::GlobOverload package

To create a glob you can pass around for tests, use this code:

  my $GLOB = do {
      no warnings 'once';
      *SOME_GLOB;
  };

The "_T::GlobOverload" package is defined when you load "Test::Specio" so you can create your own glob overloading objects. Such objects cannot be exported because the glob they return does not transfer across packages properly.

You can create such a variable like this:

  local *FOO;
  my $GLOB_OVERLOAD = _T::GlobOverload->new( \*FOO );

If you want to create a glob overloading object that returns a filehandle, do this:

  local *BAR;
  open BAR, '<', $^X or die "Could not open $^X for the test";
  my $GLOB_OVERLOAD_FH = _T::GlobOverload->new( \*BAR );