Add support for racket packages (#27564)

- Add variants for various common build flags, including support for both versions of the Racket VM environment.
- Prevent `-j` flags to `make`, which has been known to cause problems with Racket builds.
- Prefer the minimal release to improve install times. Bells and whistles carry their own runtime dependencies and should be installed via `raco`. An enterprising user may even create a `RacketPackage` class to make spack aware of `raco` installed packages.
- Match the official version numbering scheme.

5 files changed, 155 insertions, 0 deletions

diff --git a/lib/spack/docs/build_systems.rst b/lib/spack/docs/build_systems.rst
index 0ee80276b8..77fb5c7838 100644
--- a/lib/spack/docs/build_systems.rst
+++ b/lib/spack/docs/build_systems.rst
@@ -51,6 +51,7 @@ on these ideas for each distinct build system that Spack supports:
    build_systems/perlpackage
    build_systems/pythonpackage
    build_systems/rpackage
+   build_systems/racketpackage
    build_systems/rubypackage
 
 .. toctree::
diff --git a/lib/spack/docs/build_systems/racketpackage.rst b/lib/spack/docs/build_systems/racketpackage.rst
new file mode 100644
index 0000000000..8ba37ceeba
--- /dev/null
+++ b/lib/spack/docs/build_systems/racketpackage.rst
@@ -0,0 +1,46 @@
+.. Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+   Spack Project Developers. See the top-level COPYRIGHT file for details.
+
+   SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+.. _racketpackage:
+
+-------------
+RacketPackage
+-------------
+
+Much like Python, Racket packages and modules have their own special build system.
+To learn more about the specifics of Racket package system, please refer to the
+`Racket Docs <https://docs.racket-lang.org/pkg/cmdline.html>`_.
+
+^^^^^^
+Phases
+^^^^^^
+
+The ``RacketPackage`` base class provides an ``install`` phase that
+can be overridden, corresponding to the use of:
+
+.. code-block:: console
+
+   $ raco pkg install
+
+^^^^^^^
+Caveats
+^^^^^^^
+
+In principle, ``raco`` supports a second, ``setup`` phase; however, we have not
+implemented this separately, as in normal circumstances, ``install`` also handles
+running ``setup`` automatically.
+
+Unlike Python, Racket currently on supports two installation scopes for packages, user
+or system, and keeps a registry of installed packages at each scope in its configuration files.
+This means we can't simply compose a "``RACKET_PATH``" environment variable listing all of the
+places packages are installed, and update this at will.
+
+Unfortunately this means that all currently installed packages which extend Racket via ``raco pkg install``
+are accessible whenever Racket is accessible.
+
+Additionally, because Spack does not implement uninstall hooks, uninstalling a Spack  ``rkt-`` package
+will have no effect on the ``raco`` installed packages visible to your Racket installation.
+Instead, you must manually run ``raco pkg remove`` to keep the two package managers in a mutually
+consistent state.
diff --git a/lib/spack/spack/build_systems/racket.py b/lib/spack/spack/build_systems/racket.py
new file mode 100644
index 0000000000..5bb4026cf4
--- /dev/null
+++ b/lib/spack/spack/build_systems/racket.py
@@ -0,0 +1,70 @@
+# Copyright 2013-2021 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+import os
+
+import llnl.util.tty as tty
+from llnl.util.filesystem import working_dir
+
+from spack.build_environment import SPACK_NO_PARALLEL_MAKE, determine_number_of_jobs
+from spack.directives import extends
+from spack.package import PackageBase
+from spack.util.environment import env_flag
+from spack.util.executable import Executable, ProcessError
+
+
+class RacketPackage(PackageBase):
+    """Specialized class for packages that are built using Racket's
+    `raco pkg install` and `raco setup` commands.
+
+    This class provides the following phases that can be overridden:
+
+    * install
+    * setup
+    """
+    #: Package name, version, and extension on PyPI
+    maintainers = ['elfprince13']
+
+    # Default phases
+    phases = ['install']
+
+    # To be used in UI queries that require to know which
+    # build-system class we are using
+    build_system_class = 'RacketPackage'
+
+    extends('racket')
+
+    pkgs = False
+    subdirectory = None
+    name = None
+    parallel = True
+
+    @property
+    def homepage(self):
+        if self.pkgs:
+            return 'https://pkgs.racket-lang.org/package/{0}'.format(self.name)
+
+    @property
+    def build_directory(self):
+        ret = os.getcwd()
+        if self.subdirectory:
+            ret = os.path.join(ret, self.subdirectory)
+        return ret
+
+    def install(self, spec, prefix):
+        """Install everything from build directory."""
+        raco = Executable("raco")
+        with working_dir(self.build_directory):
+            allow_parallel = self.parallel and (not env_flag(SPACK_NO_PARALLEL_MAKE))
+            args = ['pkg', 'install', '-t', 'dir', '-n', self.name, '--deps', 'fail',
+                    '--ignore-implies', '--copy', '-i', '-j',
+                    str(determine_number_of_jobs(allow_parallel)),
+                    '--', os.getcwd()]
+            try:
+                raco(*args)
+            except ProcessError:
+                args.insert(-2, "--skip-installed")
+                raco(*args)
+                tty.warn(("Racket package {0} was already installed, uninstalling via "
+                          "Spack may make someone unhappy!").format(self.name))
diff --git a/lib/spack/spack/cmd/create.py b/lib/spack/spack/cmd/create.py
index 1281c6d9ef..14463127d3 100644
--- a/lib/spack/spack/cmd/create.py
+++ b/lib/spack/spack/cmd/create.py
@@ -258,6 +258,42 @@ class BazelPackageTemplate(PackageTemplate):
         bazel()"""
 
 
+class RacketPackageTemplate(PackageTemplate):
+    """Provides approriate overrides for Racket extensions"""
+    base_class_name = 'RacketPackage'
+
+    url_line = """\
+    # FIXME: set the proper location from which to fetch your package
+    git      = "git@github.com:example/example.git"
+    """
+
+    dependencies = """\
+    # FIXME: Add dependencies if required. Only add the racket dependency
+    # if you need specific versions. A generic racket dependency is
+    # added implicity by the RacketPackage class.
+    # depends_on('racket@8.3:', type=('build', 'run'))"""
+
+    body_def = """\
+    # FIXME: specify the name of the package,
+    # as it should appear to ``raco pkg install``
+    name = '{0}'
+    # FIXME: set to true if published on pkgs.racket-lang.org
+    # pkgs = False
+    # FIXME: specify path to the root directory of the
+    # package, if not the base directory
+    # subdirectory = None
+    """
+
+    def __init__(self, name, url, *args, **kwargs):
+        # If the user provided `--name rkt-scribble`, don't rename it rkt-rkt-scribble
+        if not name.startswith('rkt-'):
+            # Make it more obvious that we are renaming the package
+            tty.msg("Changing package name from {0} to rkt-{0}".format(name))
+            name = 'rkt-{0}'.format(name)
+        self.body_def = self.body_def.format(name[4:])
+        super(RacketPackageTemplate, self).__init__(name, url, *args, **kwargs)
+
+
 class PythonPackageTemplate(PackageTemplate):
     """Provides appropriate overrides for python extensions"""
     base_class_name = 'PythonPackage'
@@ -536,6 +572,7 @@ templates = {
     'bazel':      BazelPackageTemplate,
     'python':     PythonPackageTemplate,
     'r':          RPackageTemplate,
+    'racket':     RacketPackageTemplate,
     'perlmake':   PerlmakePackageTemplate,
     'perlbuild':  PerlbuildPackageTemplate,
     'octave':     OctavePackageTemplate,
diff --git a/lib/spack/spack/pkgkit.py b/lib/spack/spack/pkgkit.py
index ba1f5f377b..f4dd3dbe61 100644
--- a/lib/spack/spack/pkgkit.py
+++ b/lib/spack/spack/pkgkit.py
@@ -38,6 +38,7 @@ from spack.build_systems.perl import PerlPackage
 from spack.build_systems.python import PythonPackage
 from spack.build_systems.qmake import QMakePackage
 from spack.build_systems.r import RPackage
+from spack.build_systems.racket import RacketPackage
 from spack.build_systems.rocm import ROCmPackage
 from spack.build_systems.ruby import RubyPackage
 from spack.build_systems.scons import SConsPackage