Docs section and firedrake-install tweaks

docs/source/download.rst

@@ -104,6 +104,8 @@ gives a full list of update options. For instance additional Firedrake
 packages can be installed into an existing Firedrake installation using
 ``firedrake-update``.
 
+.. _system-requirements:
+
 System requirements
 -------------------
 
@@ -227,6 +229,49 @@ type::
 
 You should now be able to run ``firedrake-update``.
 
+Installing Firedrake with pip (experimental, Linux only)
+--------------------------------------------------------
+
+Firedrake is working towards having support for binary installs. As such there is experimental support for installing Firedrake using ``pip``, avoiding the need for a ``firedrake-install`` script. At present only Linux is tested using this install method.
+
+Requirements
+~~~~~~~~~~~~
+
+* All the system requirements listed in :ref:`system-requirements`.
+* A Firedrake-compatible PETSc installation (using our `fork of PETSc <https://github.com/firedrakeproject/petsc.git>`_). The set of flags passed to PETSc can be retrieved by passing the command ``--show-petsc-configure-options`` to ``firedrake-install``.
+* The following environment variables to be set:
+
+  * ``PETSC_DIR`` and ``PETSC_ARCH`` to point to the correct location for the PETSc installation.
+  * ``HDF5_DIR`` to ``$PETSC_DIR/$PETSC_ARCH``.
+  * ``CC`` and ``MPICC`` to point to the ``mpicc`` compiler wrapper.
+  * ``CXX`` to point to the ``mpicxx`` compiler wrapper.
+  * ``MPI_HOME`` to point to the location of the MPI library (e.g. ``/opt/mpich``).
+
+Installation
+~~~~~~~~~~~~
+
+Having set up this environment, Firedrake can now be installed (into a virtual environment) with the command::
+
+  pip install --no-binary mpi4py,h5py git+https://github.com/firedrakeproject/firedrake.git
+
+
+Removing Firedrake
+------------------
+Firedrake and its dependencies can be removed by deleting the Firedrake
+install directory. This is usually the ``firedrake`` subdirectory
+created after having run ``firedrake-install``. Note that this will not
+undo the installation of any system packages which are Firedrake
+dependencies: removing these might affect subsequently installed
+packages for which these are also dependencies.
+
+.. _Paraview: http://www.paraview.org
+.. _venv: https://docs.python.org/3/tutorial/venv.html
+.. _homebrew: https://brew.sh/
+.. _PETSc: https://www.mcs.anl.gov/petsc/
+.. _discussions: https://github.com/firedrakeproject/firedrake/discussions
+.. _issue: https://github.com/firedrakeproject/firedrake/issues
+.. _WSL: https://github.com/firedrakeproject/firedrake/wiki/Installing-on-Windows-Subsystem-for-Linux
+
 Visualisation software
 ----------------------
 
@@ -254,20 +299,3 @@ and can be built by executing::
 
 This will generate the HTML documentation (this website) on your local
 machine.
-
-Removing Firedrake
-------------------
-Firedrake and its dependencies can be removed by deleting the Firedrake
-install directory. This is usually the ``firedrake`` subdirectory
-created after having run ``firedrake-install``. Note that this will not
-undo the installation of any system packages which are Firedrake
-dependencies: removing these might affect subsequently installed
-packages for which these are also dependencies.
-
-.. _Paraview: http://www.paraview.org
-.. _venv: https://docs.python.org/3/tutorial/venv.html
-.. _homebrew: https://brew.sh/
-.. _PETSc: https://www.mcs.anl.gov/petsc/
-.. _discussions: https://github.com/firedrakeproject/firedrake/discussions
-.. _issue: https://github.com/firedrakeproject/firedrake/issues
-.. _WSL: https://github.com/firedrakeproject/firedrake/wiki/Installing-on-Windows-Subsystem-for-Linux

firedrake/scripts/firedrake-install

@@ -1387,7 +1387,7 @@ def build_update_script():
 
 
 if args.rebuild_script:
-    os.chdir(os.path.dirname(os.path.realpath(__file__)) + ("/../.."))
+    os.chdir(os.path.dirname(os.path.realpath(__file__)) + ("/../../.."))
 
     build_update_script()
 
@@ -1787,9 +1787,8 @@ if mode == "install":
             packages.remove("petsc")
         except ValueError:
             log.warning("PETSc wasn't in dependencies list")
-
-    # Need to install petsc first in order to resolve hdf5 dependency.
-    if not args.honour_petsc_dir:
+    else:
+        # Need to install petsc first in order to resolve hdf5 dependency.
         with environment(**compiler_env):
             with pipargs("--no-deps"):
                 packages.remove("petsc")
@@ -1854,11 +1853,6 @@ if mode == "install":
     with pipargs("--no-deps"), environment(**compiler_env, **link_env):
         install("firedrake/")
 
-    # Work around easy-install.pth bug.
-    try:
-        packages.remove("petsc")
-    except ValueError:
-        pass
     packages.remove("petsc4py")
 
 else:
@@ -1906,7 +1900,10 @@ else:
         clean("slepc4py")
         shutil.move("slepc4py", "slepc4py_old")
 
-    packages.remove("petsc")
+    try:
+        packages.remove("petsc")
+    except ValueError:
+        log.warning("PETSc wasn't in dependencies list")
     packages.remove("petsc4py")
 
     if args.clean: