Fix SPACK-21: stage names are too long

Stage names now hash dependencies like install prefixes.

lib/spack/spack/directory_layout.py

@@ -138,18 +138,8 @@ def __init__(self, root, **kwargs):
 
     def relative_path_for_spec(self, spec):
         _check_concrete(spec)
-
-        path = join_path(
-            spec.architecture,
-            spec.compiler,
-            "%s@%s%s" % (spec.name, spec.version, spec.variants))
-
-        if spec.dependencies:
-            path += "-"
-            sha1 = spec.dependencies.sha1()
-            path += sha1[:self.prefix_size]
-
-        return path
+        dir_name = spec.format('$_$@$+$#')
+        return join_path(spec.architecture, spec.compiler, dir_name)
 
 
     def write_spec(self, spec, path):

lib/spack/spack/package.py

@@ -407,7 +407,7 @@ def stage(self):
         if self._stage is None:
             mirror_path = "%s/%s" % (self.name, os.path.basename(self.url))
             self._stage = Stage(
-                self.url, mirror_path=mirror_path, name=str(self.spec))
+                self.url, mirror_path=mirror_path, name=self.spec.short_spec)
         return self._stage
 
 

lib/spack/spack/spec.py

@@ -465,6 +465,13 @@ def preorder_traversal(self, visited=None, d=0, **kwargs):
                 yield elt
 
 
+    @property
+    def short_spec(self):
+        """Returns a version of the spec with the dependencies hashed
+           instead of completely enumerated."""
+        return self.format('$_$@$%@$+$=$#')
+
+
     @property
     def prefix(self):
         return Prefix(spack.install_layout.path_for_spec(self))
@@ -998,15 +1005,18 @@ def format(self, format_string='$_$@$%@$+$=', **kwargs):
                $%@  Compiler & compiler version
                $+   Options
                $=   Architecture
-               $#   Dependencies' 6-char sha1 prefix
+               $#   Dependencies' 8-char sha1 prefix
                $$   $
 
            Anything else is copied verbatim into the output stream.
 
            *Example:*  ``$_$@$+`` translates to the name, version, and options
            of the package, but no dependencies, arch, or compiler.
+
+           TODO: allow, e.g., $6# to customize short hash length
+           TODO: allow, e.g., $## for full hash.
            """
-        color = kwargs.get('color', False)
+        color    = kwargs.get('color', False)
         length = len(format_string)
         out = StringIO()
         escape = compiler = False
@@ -1037,7 +1047,7 @@ def write(s, c):
                         write(c + str(self.architecture), c)
                 elif c == '#':
                     if self.dependencies:
-                        out.write('-' + self.dependencies.sha1()[:6])
+                        out.write('-' + self.dependencies.sha1()[:8])
                 elif c == '$':
                     out.write('$')
                 escape = False