A test rule that compares two binary files or two directories.
Similar to `bazel-skylib`'s [`diff_test`](https://github.com/bazelbuild/bazel-skylib/blob/main/rules/diff_test.bzl)
but also supports comparing directories.
The rule uses a Bash command (diff) on Linux/macOS/non-Windows, and a cmd.exe
command (fc.exe) on Windows (no Bash is required).
## diff_test
diff_test(name, file1, file2, size, timeout, kwargs)
A test that compares two files.
The test succeeds if the files' contents match.
**PARAMETERS**
| Name | Description | Default Value |
| :------------- | :------------- | :------------- |
| name | The name of the test rule. | none |
| file1 | Label of the file to compare to <code>file2</code>. | none |
| file2 | Label of the file to compare to <code>file1</code>. | none |
| size | standard attribute for tests | None |
| timeout | standard attribute for tests. Defaults to "short" if both timeout and size are unspecified. | None |
| kwargs | The <a href="https://docs.bazel.build/versions/main/be/common-definitions.html#common-attributes-tests">common attributes for tests</a>. | none |