Add or replace variants on a test function

A family of functions for managing globally registered variant() objects across all HTEST_FN-based functions for the duration of the session.

Usage

plug_variant(test, name, impl, origin = c("user", "package"))

swap_variant(test, name, impl, origin = c("user", "package"))

clear_htest_defs(cls = NULL)

Arguments

test

A test function built with HTEST_FN(), e.g. TTEST.

name

A string naming the variant to add or replace.

impl

A variant() object.

origin

One of "user" (default, session-scoped) or "package" (permanent, intended for .onLoad()).

cls

A string naming the test class to clear (e.g. "ttest"). When NULL (default), all globally registered variants are cleared.

Value

plug_variant(), swap_variant(), and clear_htest_defs() return NULL invisibly, called for their side effects. get_htest_defs() returns a list of test_define() objects, or an empty list if none have been registered for the given cls.

Functions

• plug_variant(): Adds a new named variant() to an existing test function. Hard-errors if the name already exists or if name is "default".

• swap_variant(): Replaces an existing named variant(). Hard-errors if the name does not exist or if name is "default".

• clear_htest_defs(): Resets globally registered variants, either fully or scoped to a specific cls. Only "user"-originated entries are removed — "package" entries are always preserved.

Precedence

Globally registered variants sit between built-in definitions and the pipeline. The full priority order, from lowest to highest, is:

1. Built-in variants (declared inside HTEST_FN)

2. Global variants registered via plug_variant() or swap_variant()

See also

HTEST_FN(), test_define(), variant()