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Test::Harness::Straps - detailed analysis of test results


  use Test::Harness::Straps;

  my $strap = Test::Harness::Straps->new;

  # Various ways to interpret a test
  my $results = $strap->analyze($name, \@test_output);
  my $results = $strap->analyze_fh($name, $test_filehandle);
  my $results = $strap->analyze_file($test_file);

  my %total = $strap->total_results;

  # Altering the behavior of the strap  UNIMPLEMENTED
  my $verbose_output = $strap->dump_verbose();


THIS MODULE IS FOR BACKWARDS COMPATIBILITY ONLY! No further development is planned, no bugs will be fixed.

For customizable TAP parsing please use TAP::Parser instead.


Test::Harness is limited to printing out its results. This makes analysis of the test results difficult for anything but a human. To make it easier for programs to work with test results, we provide Test::Harness::Straps. Instead of printing the results, straps provide them as raw data. You can also configure how the tests are to be run.

The interface is currently incomplete. Please contact the author if you'd like a feature added or something change or just have comments.



  my $strap = Test::Harness::Straps->new;

Initialize a new strap.


Initialize the internal state of a strap to make it ready for parsing.


$strap->analyze( $name, \@output_lines )

    my $results = $strap->analyze($name, \@test_output);

Analyzes the output of a single test, assigning it the given $name for use in the total report. Returns the $results of the test. See Results.

@test_output should be the raw output from the test, including newlines.

    my $results = $strap->analyze_fh($name, $test_filehandle);

Like analyze, but it reads from the given filehandle.

$strap->analyze_file( $test_file )

    my $results = $strap->analyze_file($test_file);

Like analyze, but it runs the given $test_file and parses its results. It will also use that name for the total report.

Returns the full command line that will be run to test $file.

Returns the command that runs the test. Combine this with _switches() to build a command line.

Typically this is $^X, but you can set $ENV{HARNESS_PERL} to use a different Perl than what you're running the harness under. This might be to run a threaded Perl, for example.

You can also overload this method if you've built your own strap subclass, such as a PHP interpreter for a PHP-based strap.

Formats and returns the switches necessary to run the test.

Returns only defined, non-blank, trimmed switches from the parms passed.

  local $ENV{PERL5LIB} = $self->_INC2PERL5LIB;

Takes the current value of @INC and turns it into something suitable for putting onto PERL5LIB.

  my @filtered_inc = $self->_filtered_INC;

Shortens @INC by removing redundant and unnecessary entries. Necessary for OSes with limited command line lengths, like VMS.


This restores the original value of the PERL5LIB environment variable. Necessary on VMS, otherwise a no-op.


Methods for identifying what sort of line you're looking at.

    my $is_diagnostic = $strap->_is_diagnostic($line, \$comment);

Checks if the given line is a comment. If so, it will place it into $comment (sans #).

  my $is_header = $strap->_is_header($line);

Checks if the given line is a header (1..M) line. If so, it places how many tests there will be in $strap->{max}, a list of which tests are todo in $strap->{todo} and if the whole test was skipped $strap->{skip_all} contains the reason.

  my $is_bail_out = $strap->_is_bail_out($line, \$reason);

Checks if the line is a "Bail out!". Places the reason for bailing (if any) in $reason.


Resets things like $strap->{max} , $strap->{skip_all}, etc. so it's ready to parse the next file.


See examples/mini_harness.plx for an example of use.


Michael G Schwern <schwern at>, currently maintained by Andy Lester <andy at>.