Setup for Rails

Install

gem'parallel_tests',group:[:development,:test]

Add toconfig/database.yml

test:database:yourproject_test<%= ENV['TEST_ENV_NUMBER'] %>

Create additional database(s)

rake parallel:create

(Multi-DB) Create individual database

rake parallel:create:<database>rake parallel:create:secondary

Copy development schema (repeat after migrations)

rake parallel:prepare

Run migrations in additional database(s) (repeat after migrations)

rake parallel:migrate

(Multi-DB) Run migrations in individual database

rake parallel:migrate:<database>

Setup environment from scratch (create db and loads schema, useful for CI)

rake parallel:setup

Drop all test databases

rake parallel:drop

(Multi-DB) Drop individual test database

rake parallel:drop:<database>

Run!

rake parallel:test          # Minitestrake parallel:spec          # RSpecrake parallel:features      # Cucumberrake parallel:features-spinach       # Spinachrake "parallel:test[1]" --> force 1 CPU --> 86 secondsrake parallel:test    --> got 2 CPUs? --> 47 secondsrake parallel:test    --> got 4 CPUs? --> 26 seconds...

rake "parallel:test[^test/unit]" # every test file in test/unit folderrake "parallel:test[user]"  # run users_controller + user_helper + user testsrake "parallel:test['user|product']"  # run user and product related testsrake "parallel:spec['spec\/(?!features)']" # run RSpec tests except the tests in spec/features

Example output

2 processes for 210 specs, ~ 105 specs per process... test output ...843 examples, 0 failures, 1 pendingTook 29.925333 seconds

Run an arbitrary task in parallel

RAILS_ENV=test parallel_test -e"rake my:custom:task"# orrake"parallel:rake[my:custom:task]"# limited parallelismrake"parallel:rake[my:custom:task,2]"

Running setup or teardown once

require"parallel_tests"# preparation:# affected by race-condition: first process may boot slower than the second# the Process.ppid will be the pod of the process that started the parallel tests# when not using TEST_ENV_NUMBER we use a unique file per process because ppid would be the users shelldone="/tmp/parallel-setup-done-#{ENV['TEST_ENV_NUMBER'] ?Process.ppid :Process.pid}"ifParallelTests.first_process?do_somethingFile.writedone,"true"elsesleep0.1untilFile.exist?(done)end# cleanup:# could also use last_process? but that is just the last process to start, not the last to finishat_exitdoifParallelTests.first_process?File.unlinkdoneParallelTests.wait_for_other_processes_to_finishundo_somethingendend

Even test group runtimes

RSpec

--format progress--format ParallelTests::RSpec::RuntimeLogger --out tmp/parallel_runtime_rspec.log

Minitest

ifENV['RECORD_RUNTIME']require'parallel_tests/test/runtime_logger'# ParallelTests::Test::RuntimeLogger.logfile = "tmp/parallel_runtime_test.log" # where to write itend

Loggers

RSpec: SummaryLogger

--format progress--format ParallelTests::RSpec::SummaryLogger --out tmp/spec_summary.log

RSpec: FailuresLogger

rspec /path/to/my_spec.rb:123# should do something

--format progress--format ParallelTests::RSpec::FailuresLogger --out tmp/failing_specs.log

RSpec: VerboseLogger

# PID, parallel process number, spec status, example description[14403] [2] [STARTED] Foo foo[14402] [1] [STARTED] Bar bar[14402] [1] [PASSED] Bar bar

  --format ParallelTests::RSpec::VerboseLogger

Cucumber: FailuresLogger

cucumber --format ParallelTests::Cucumber::FailuresLogger --out tmp/cucumber_failures.log

parallel: --format progress --format ParallelTests::Cucumber::FailuresLogger --out tmp/cucumber_failures.log

cucumber @tmp/cucumber_failures.log

Setup for non-rails

gem install parallel_tests# go to your project dirparallel_testparallel_rspecparallel_cucumberparallel_spinach

-n PROCESSES                     How many processes to use, default: available CPUs-p, --pattern PATTERN            run tests matching this regex pattern    --exclude-pattern PATTERN    exclude tests matching this regex pattern    --group-by TYPE              group tests by:                                 found - order of finding files                                 steps - number of cucumber/spinach steps                                 scenarios - individual cucumber scenarios                                 filesize - by size of the file                                 runtime - info from runtime log                                 default - runtime when runtime log is filled otherwise filesize-m, --multiply-processes COUNT   use given number as a multiplier of processes to run-s, --single PATTERN             Run all matching files in the same process-i, --isolate                    Do not run any other tests in the group used by --single(-s)    --isolate-n PROCESSES        Use 'isolate'  singles with number of processes, default: 1    --highest-exit-status        Exit with the highest exit status provided by test run(s)    --failure-exit-code INT      Specify the exit code to use when tests fail    --specify-groups SPECS       Use 'specify-groups' if you want to specify multiple specs running in multiple                                 processes in a specific formation. Commas indicate specs in the same process,                                 pipes indicate specs in a new process. If SPECS is a '-' the value for this                                 option is read from STDIN instead. Cannot use with --single, --isolate, or                                 --isolate-n.  Ex.                                 $ parallel_tests -n 3 . --specify-groups '1_spec.rb,2_spec.rb|3_spec.rb'                                   Process 1 will contain 1_spec.rb and 2_spec.rb                                   Process 2 will contain 3_spec.rb                                   Process 3 will contain all other specs    --only-group GROUP_INDEX[,GROUP_INDEX]                                 Only run the given group numbers.                                 Changes `--group-by` default to 'filesize'.-e, --exec COMMAND               execute COMMAND in parallel and with ENV['TEST_ENV_NUMBER']    --exec-args COMMAND          execute COMMAND in parallel with test files as arguments, for example:                                 $ parallel_tests --exec-args echo                                 > echo spec/a_spec.rb spec/b_spec.rb-o, --test-options 'OPTIONS'     execute test commands with those options-t, --type TYPE                  test(default) / rspec / cucumber / spinach    --suffix PATTERN             override built in test file pattern (should match suffix):                                 '_spec.rb$' - matches rspec files                                 '_(test|spec).rb$' - matches test or spec files    --serialize-stdout           Serialize stdout output, nothing will be written until everything is done    --prefix-output-with-test-env-number                                 Prefixes test env number to the output when not using --serialize-stdout    --combine-stderr             Combine stderr into stdout, useful in conjunction with --serialize-stdout    --non-parallel               execute same commands but do not in parallel, needs --exec    --no-symlinks                Do not traverse symbolic links to find test files    --ignore-tags PATTERN        When counting steps ignore scenarios with tags that match this pattern    --nice                       execute test commands with low priority.    --runtime-log PATH           Location of previously recorded test runtimes    --allowed-missing COUNT      Allowed percentage of missing runtimes (default = 50)    --allow-duplicates           When detecting files to run, allow duplicates    --unknown-runtime SECONDS    Use given number as unknown runtime (otherwise use average time)    --first-is-1                 Use "1" as TEST_ENV_NUMBER to not reuse the default test environment    --fail-fast                  Stop all groups when one group fails (best used with --test-options '--fail-fast' if supported    --test-file-limit LIMIT      Limit to this number of files per test run by batching                                 (for windows set to ~100 to stay below 8192 max command limit, might have bugs from reusing test-env-number                                 and summarizing partial results)    --verbose                    Print debug output    --verbose-command            Combines options --verbose-process-command and --verbose-rerun-command    --verbose-process-command    Print the command that will be executed by each process before it begins    --verbose-rerun-command      After a process fails, print the command executed by that process    --quiet                      Print only tests output-v, --version                    Show Version-h, --help                       Show this.

parallel_test -n 3 -e'ruby -e "puts %[hello from process #{ENV[:TEST_ENV_NUMBER.to_s].inspect}]"'hello from process"2"hello from process""hello from process"3"

parallel_test -n 3 --exec-argsechospec/a_spec.rb spec/b_spec.rb spec/c_spec.rb spec/d_spec.rbspec/e_spec.rb

parallel_test -n 3 --exec-args"sh -c\"echo 'hello world' && rspec\$@\" --"

TIPS

RSpec

Cucumber

General

Authors

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