graph: Allow store file names for 'derivation' and 'references' graphs.

* guix/scripts/graph.scm (%derivation-node-type)[convert]: Add
'derivation-path?' and catch-all clauses.
(%reference-node-type)[convert]: Add 'store-path?' and catch-all
clauses.
(assert-package, nodes-from-package): New procedures.
(%package-node-type, %bag-node-type,%bag-with-origins-node-type)
(%bag-emerged-node-type): Add 'convert' field
(guix-graph): Rename 'packages' to 'items' and
allow 'store-path?' arguments.
* guix/graph.scm (<node-type>)[convert]: Adjust comment.
* doc/guix.texi (Invoking guix graph): Document it.

1 files changed, 14 insertions, 0 deletions

diff --git a/doc/guix.texi b/doc/guix.texi
index 3f0106be02..d88cc256d7 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -5161,6 +5161,12 @@ derivations (@pxref{Derivations}) and plain store items.  Compared to
 the above representation, many additional nodes are visible, including
 build scripts, patches, Guile modules, etc.
 
+For this type of graph, it is also possible to pass a @file{.drv} file
+name instead of a package name, as in:
+
+@example
+guix graph -t derivation `guix system build -d my-config.scm`
+@end example
 @end table
 
 All the types above correspond to @emph{build-time dependencies}.  The
@@ -5173,6 +5179,14 @@ by @command{guix gc --references} (@pxref{Invoking guix gc}).
 
 If the given package output is not available in the store, @command{guix
 graph} attempts to obtain dependency information from substitutes.
+
+Here you can also pass a store file name instead of a package name.  For
+example, the command below produces the reference graph of your profile
+(which can be big!):
+
+@example
+guix graph -t references `readlink -f ~/.guix-profile`
+@end example
 @end table
 
 The available options are the following: