graphviz: Tame Language Bindings (#1089)

graphviz: 
  * Download from Fedora projet, as main graphviz site not working.
  * Disable java because Spack does not yet support Java, and the system might not have it installed.
  * Added all language binding variants; disabled enough in the default configuration to avoid dependencies.
  * Removed alternate download location (turned into comments).
  * Turn off all language bindings by default.
  * Raise an exception on bindings that have not been verified to work.
  * Added text indicating what works and doesn't work when user runs `spack info`.

1 files changed, 79 insertions, 18 deletions

diff --git a/var/spack/repos/builtin/packages/graphviz/package.py b/var/spack/repos/builtin/packages/graphviz/package.py
index 1bf6c70926..a6d3234695 100644
--- a/var/spack/repos/builtin/packages/graphviz/package.py
+++ b/var/spack/repos/builtin/packages/graphviz/package.py
@@ -29,33 +29,94 @@ import shutil
 
 class Graphviz(AutotoolsPackage):
     """Graph Visualization Software"""
-    homepage = "http://www.graphviz.org"
-    url      = "http://www.graphviz.org/pub/graphviz/stable/SOURCES/graphviz-2.38.0.tar.gz"
+    homepage = 'http://www.graphviz.org'
+    url      = 'http://www.graphviz.org/pub/graphviz/stable/SOURCES/graphviz-2.38.0.tar.gz'
 
     version('2.38.0', '5b6a829b2ac94efcd5fa3c223ed6d3ae')
 
-    # By default disable optional Perl language support to prevent build issues
-    # related to missing Perl packages. If spack begins support for Perl in the
-    # future, this package can be updated to depend_on('perl') and the
-    # ncecessary devel packages.
-    variant(
-        'perl', default=False,
-        description='Enable if you need the optional Perl language bindings.')
+    # We try to leave language bindings enabled if they don't cause
+    # build issues or add dependencies.
+    variant('swig', default=False,
+            description='Enable for optional swig language bindings'
+            ' (not yet functional)')
+    variant('sharp', default=False,
+            description='Enable for optional sharp language bindings'
+            ' (not yet functional)')
+    variant('go', default=False,
+            description='Enable for optional go language bindings'
+            ' (not yet functional)')
+    variant('guile', default=False,
+            description='Enable for optional guile language bindings'
+            ' (not yet functional)')
+    variant('io', default=False,
+            description='Enable for optional io language bindings'
+            ' (not yet functional)')
+    variant('java', default=False,  # Spack has no Java support
+            description='Enable for optional java language bindings')
+    variant('lua', default=False,
+            description='Enable for optional lua language bindings'
+            ' (not yet functional)')
+    variant('ocaml', default=False,
+            description='Enable for optional ocaml language bindings'
+            ' (not yet functional)')
+    variant('perl', default=False,    # Spack has no Perl support
+            description='Enable for optional perl language bindings')
+    variant('php', default=False,
+            description='Enable for optional php language bindings'
+            ' (not yet functional)')
+    variant('python', default=False,    # Build issues with Python 2/3
+            description='Enable for optional python language bindings'
+            ' (not yet functional)')
+    variant('r', default=False,
+            description='Enable for optional r language bindings'
+            ' (not yet functional)')
+    variant('ruby', default=False,
+            description='Enable for optional ruby language bindings'
+            ' (not yet functional)')
+    variant('tcl', default=False,
+            description='Enable for optional tcl language bindings'
+            ' (not yet functional)')
 
     parallel = False
 
-    depends_on("swig")
-    depends_on("python")
-    depends_on("ghostscript")
-    depends_on("freetype")
-    depends_on("expat")
-    depends_on("libtool")
-    depends_on("pkg-config", type='build')
+    depends_on('swig', when='+swig')
+    depends_on('ghostscript')
+    depends_on('freetype')
+    depends_on('expat')
+    depends_on('libtool')
+    depends_on('pkg-config', type='build')
+
+    depends_on('jdk', when='+java')
+    depends_on('python@2:2.8', when='+python')
 
     def configure_args(self):
         options = []
-        if '+perl' not in self.spec:
-            options.append('--disable-perl')
+
+        # These language bindings have been tested, we know they work.
+        tested_bindings = ('+java', '+perl')
+
+        # These language bindings have not yet been tested.  They
+        # likely need additional dependencies to get working.
+        untested_bindings = (
+            '+swig', '+sharp', '+go', '+guile', '+io',
+            '+lua', '+ocaml', '+php',
+            '+python', '+r', '+ruby', '+tcl')
+
+        for var in untested_bindings:
+            if var in spec:
+                raise SpackException(
+                    "The variant {0} for language bindings has not been "
+                    "tested.  It might or might not work.  To try it "
+                    "out, run `spack edit graphviz`, and then move '{0}' "
+                    "from the `untested_bindings` list to the "
+                    "`tested_bindings` list.  Be prepared to add "
+                    "required dependencies.  "
+                    "Please then submit a pull request to "
+                    "http://github.com/llnl/spack")
+
+        for var in tested_bindings:
+            enable = 'enable' if (var in spec) else 'disable'
+            options.append('--%s-%s' % (enable, var[1:]))
 
         # On OSX fix the compiler error:
         # In file included from tkStubLib.c:15: