To add a collaborator to this project you will need to use the Relish gem to add the collaborator via a terminal command. Soon you'll be able to also add collaborators here!
More about adding a collaborator`output` matcher
The output matcher provides a way to assert that the block has emitted content to either
$stdout or $stderr.
With no arg, passes if the block outputs to_stdout or to_stderr. With a string, passes
if the blocks outputs that specific string to_stdout or to_stderr. With a regexp or
matcher, passes if the blocks outputs a string to_stdout or to_stderr that matches.
Note: to_stdout and to_stderr work by temporarily replacing $stdout or $stderr, so
they're not able to intercept stream output that explicitly uses STDOUT/STDERR or that
uses a reference to $stdout/$stderr that was stored before the matcher is used.
To capture output from any spawned subprocess as well, use to_stdout_from_any_process
or to_stderr_from_any_process. Output from any process that inherits the main process's
corresponding standard stream will be captured.
Note: to_stdout_from_any_process and to_stderr_from_any_process use tempfiles to
capture output, and are thus significantly (~30x) slower than to_stdout and to_stderr.
- Scenarios
-
- output_to_stdout matcher
- output_to_stderr matcher
- output_to_stdout_from_any_process matcher
- output_to_stderr_from_any_process matcher
- output_to_stdout matcher
-
- Given
-
a file named "output_to_stdout_spec.rb" with:
RSpec.describe "output.to_stdout matcher" do specify { expect { print('foo') }.to output.to_stdout } specify { expect { print('foo') }.to output('foo').to_stdout } specify { expect { print('foo') }.to output(/foo/).to_stdout } specify { expect { }.to_not output.to_stdout } specify { expect { print('foo') }.to_not output('bar').to_stdout } specify { expect { print('foo') }.to_not output(/bar/).to_stdout } # deliberate failures specify { expect { }.to output.to_stdout } specify { expect { }.to output('foo').to_stdout } specify { expect { print('foo') }.to_not output.to_stdout } specify { expect { print('foo') }.to output('bar').to_stdout } specify { expect { print('foo') }.to output(/bar/).to_stdout } end - When
-
I run
rspec output_to_stdout_spec.rb - Then
-
the output should contain all of these:
11 examples, 5 failures expected block to output to stdout, but did not expected block to not output to stdout, but output "foo" expected block to output "bar" to stdout, but output "foo" expected block to output "foo" to stdout, but output nothing expected block to output /bar/ to stdout, but output "foo"
- output_to_stderr matcher
-
- Given
-
a file named "output_to_stderr.rb" with:
RSpec.describe "output_to_stderr matcher" do specify { expect { warn('foo') }.to output.to_stderr } specify { expect { warn('foo') }.to output("foo\n").to_stderr } specify { expect { warn('foo') }.to output(/foo/).to_stderr } specify { expect { }.to_not output.to_stderr } specify { expect { warn('foo') }.to_not output('bar').to_stderr } specify { expect { warn('foo') }.to_not output(/bar/).to_stderr } # deliberate failures specify { expect { }.to output.to_stderr } specify { expect { }.to output('foo').to_stderr } specify { expect { warn('foo') }.to_not output.to_stderr } specify { expect { warn('foo') }.to output('bar').to_stderr } specify { expect { warn('foo') }.to output(/bar/).to_stderr } end - When
-
I run
rspec output_to_stderr.rb - Then
-
the output should contain all of these:
11 examples, 5 failures expected block to output to stderr, but did not expected block to not output to stderr, but output "foo expected block to output "bar" to stderr, but output "foo " expected block to output "foo" to stderr, but output nothing expected block to output /bar/ to stderr, but output "foo "
- output_to_stdout_from_any_process matcher
-
- Given
-
a file named "output_to_stdout_from_any_process_spec.rb" with:
RSpec.describe "output.to_stdout_from_any_process matcher" do specify { expect { system('printf foo') }.to output.to_stdout_from_any_process } specify { expect { system('printf foo') }.to output("foo").to_stdout_from_any_process } specify { expect { system('printf foo') }.to output(/foo/).to_stdout_from_any_process } specify { expect { }.to_not output.to_stdout_from_any_process } specify { expect { system('printf foo') }.to_not output("bar").to_stdout_from_any_process } specify { expect { system('printf foo') }.to_not output(/bar/).to_stdout_from_any_process } # deliberate failures specify { expect { }.to output.to_stdout_from_any_process } specify { expect { }.to output('foo').to_stdout_from_any_process } specify { expect { system('printf foo') }.to_not output.to_stdout_from_any_process } specify { expect { system('printf foo') }.to output('bar').to_stdout_from_any_process } specify { expect { system('printf foo') }.to output(/bar/).to_stdout_from_any_process } end - When
-
I run
rspec output_to_stdout_from_any_process_spec.rb - Then
-
the output should contain all of these:
11 examples, 5 failures expected block to output to stdout, but did not expected block to not output to stdout, but output "foo" expected block to output "bar" to stdout, but output "foo" expected block to output "foo" to stdout, but output nothing expected block to output /bar/ to stdout, but output "foo"
- output_to_stderr_from_any_process matcher
-
- Given
-
a file named "output_to_stderr_from_any_process_spec.rb" with:
RSpec.describe "output.to_stderr_from_any_process matcher" do specify { expect { system('printf foo 1>&2') }.to output.to_stderr_from_any_process } specify { expect { system('printf foo 1>&2') }.to output("foo").to_stderr_from_any_process } specify { expect { system('printf foo 1>&2') }.to output(/foo/).to_stderr_from_any_process } specify { expect { }.to_not output.to_stderr_from_any_process } specify { expect { system('printf foo 1>&2') }.to_not output("bar").to_stderr_from_any_process } specify { expect { system('printf foo 1>&2') }.to_not output(/bar/).to_stderr_from_any_process } # deliberate failures specify { expect { }.to output.to_stderr_from_any_process } specify { expect { }.to output('foo').to_stderr_from_any_process } specify { expect { system('printf foo 1>&2') }.to_not output.to_stderr_from_any_process } specify { expect { system('printf foo 1>&2') }.to output('bar').to_stderr_from_any_process } specify { expect { system('printf foo 1>&2') }.to output(/bar/).to_stderr_from_any_process } end - When
-
I run
rspec output_to_stderr_from_any_process_spec.rb - Then
-
the output should contain all of these:
11 examples, 5 failures expected block to output to stderr, but did not expected block to not output to stderr, but output "foo" expected block to output "bar" to stderr, but output "foo" expected block to output "foo" to stderr, but output nothing expected block to output /bar/ to stderr, but output "foo"
Last published 9 months ago by Jon Rowe.