Remove the unused pygmt.test() function (#2652)

doc/api/index.rst

@@ -203,7 +203,6 @@ Miscellaneous
     :toctree: generated
 
     which
-    test
     print_clib_info
     show_versions
 

pygmt/__init__.py

@@ -182,55 +182,3 @@ def _get_ghostscript_version():
     print(f"  ghostscript: {_get_ghostscript_version()}", file=file)
 
     print_clib_info(file=file)
-
-
-def test(doctest=True, verbose=True, coverage=False, figures=True):
-    """
-    Run the test suite.
-
-    Uses `pytest <http://pytest.org/>`__ to discover and run the tests. If you
-    haven't already, you can install it with `mamba
-    <https://mamba.readthedocs.org/>`__ or `pip
-    <https://pip.pypa.io/en/stable/>`__.
-
-    Parameters
-    ----------
-    doctest : bool
-        If ``True``, will run the doctests as well (code examples that start
-        with a ``>>>`` in the docs).
-    verbose : bool
-        If ``True``, will print extra information during the test run.
-    coverage : bool
-        If ``True``, will run test coverage analysis on the code as well.
-        Requires ``pytest-cov``.
-    figures : bool
-        If ``True``, will test generated figures against saved baseline
-        figures.  Requires ``pytest-mpl`` and ``matplotlib``.
-
-    Raises
-    ------
-
-    AssertionError
-        If pytest returns a non-zero error code indicating that some tests have
-        failed.
-    """
-    import pytest  # pylint: disable=import-outside-toplevel
-
-    show_versions()
-
-    package = __name__
-
-    args = []
-    if verbose:
-        args.append("-vv")
-    if coverage:
-        args.append(f"--cov={package}")
-        args.append("--cov-report=term-missing")
-    if doctest:
-        args.append("--doctest-modules")
-    if figures:
-        args.append("--mpl")
-    args.append("--pyargs")
-    args.append(package)
-    status = pytest.main(args)
-    assert status == 0, "Some tests have failed."