compare

Comparison tests

This document covers the comparison tests, that are tests that are executed through the command line that compare the behavior of Scriggo with the behavior of gc.

• Running existing tests
• Adding new tests
  • Specifying a testing mode
  • Available testing modes
  • Adding tests from gc
    • License

Running existing tests

1. Ensure that the latest version of the scriggo command is installed and available on your system.
2. Enter test/compare/cmd
3. Generate the sources with go generate
4. Enter test/compare
5. Build the compare command with go build
6. Run the comparison tests with ./compare; this step may take a while.

You may want to run ./compare -h to see the available options.

Adding new tests

A test consists in a text file containing source code, which can be put everywhere inside the directory testdata. Directory names has no special meaning, except for test/compare/sources/github.com-golang-go (see the section below).

Every test source code must specify a testing mode. See the section Testing modes for more information.

Warning: when a new test is added or an existing one is modified, pay attention to not run formatting tools (as go fmt) on tests. Some of them test some special syntaxes that are changed by such tools.

Specifying a testing mode

A testing mode can be specified using a comment at the first non-empty line of the test file.

For programs:

// mode [options]

for templates:

{# mode [options] #}

The option that is currently available is:

• -disallowGoStatement: disallow the go statement

Note that in templates the line that specifies the mode cannot contain anything but the comment.

Available testing modes

Testing modes are listed in the table below. If you want, for example, test a program source code with the mode errorcheck, the first non-empty line of the file must be

// errorcheck

• A golden file associated to a test is a text file with the same path as the test but with extension .golden instead of .html. Golden files can have comments, that are lines that get replaced by empty lines during comparison. A comment line must start with //. Important: when comparing the output of a test with its goldenfile, leading and trailing space is removed.

• A dir-directory associated to a test is a directory with the same path as the test, but which ends in .dir instead of .go or .html. For instance, a test located at test/path/testname.go has an associated dir-directory with path test/path/testname.dir.

Only one mode per test is supported. If more than one comment containing a mode is present in a file, only the first is considered. This allow, for example, the disabling of a test without the needing to change the existing mode.

// run

...test...

can be changed to

// skip : cannot run for reason X

// run

...test...

Adding tests from gc

The directory testdata/github.com-golang-go contains tests taken from https://github.com/golang/go/tree/master/test. Such tests should be changed only when necessary to run the test with Scriggo successfully.

License

Tests taken from https://github.com/golang/go/tree/master/test are covered by a license which can be found in the LICENSE file in the directory github.com-golang-go/ (github.com-golang-go/LICENSE).