profiles: Do not repeat entries in 'manifest' file.

Fixes <https://issues.guix.gnu.org/55499>.
Reported by Ricardo Wurmus <rekado@elephly.net>.

With this change, the manifest file created for:

  guix install r r-seurat r-cistopic r-monocle3 r-cicero-monocle3 r-assertthat

goes from 5.7M to 176K.  Likewise, on this profile, wall-clock time of:

  GUIX_PROFILING=gc guix package -I

goes from 0.7s to 0.1s, with heap usage going from 55M to 9M.

* guix/profiles.scm (manifest->gexp)[optional]: New procedure.
[entry->gexp]: Turn into a monadic procedure.  Return a 'repeated' sexp
if ENTRY was already visited before.
Adjust caller accordingly.  Bump manifest version.
(sexp->manifest)[sexp->manifest-entry]: Turn into a monadic procedure.
Add case for 'repeated' nodes.  Add each entry to the current state
vhash.
Add clause for version 4 manifests.
[sexp->manifest-entry/v3]: New procedure, with former
'sexp->manifest-entry' code.
* tests/profiles.scm ("deduplication of repeated entries"): New test.
* guix/build/profiles.scm (manifest-sexp->inputs+search-paths)[let-fields]:
New macro.
Use it.  Expect version 4.  Add clause for 'repeated' nodes.

1 files changed, 25 insertions, 7 deletions

diff --git a/guix/build/profiles.scm b/guix/build/profiles.scm
index f9875ca92e..2ab76bde74 100644
--- a/guix/build/profiles.scm
+++ b/guix/build/profiles.scm
@@ -149,19 +149,33 @@ instead make DIRECTORY a \"real\" directory containing symlinks."
   "Parse MANIFEST, an sexp as produced by 'manifest->gexp', and return two
 values: the list of store items of its manifest entries, and the list of
 search path specifications."
+  (define-syntax let-fields
+    (syntax-rules ()
+      ;; Bind the fields NAME of LST to same-named variables in the lexical
+      ;; scope of BODY.
+      ((_ lst (name rest ...) body ...)
+       (let ((name (match (assq 'name lst)
+                     ((_ value) value)
+                     (#f '()))))
+         (let-fields lst (rest ...) body ...)))
+      ((_ lst () body ...)
+       (begin body ...))))
+
   (match manifest                            ;this must match 'manifest->gexp'
-    (('manifest ('version 3)
+    (('manifest ('version 4)
                 ('packages (entries ...)))
      (let loop ((entries entries)
                 (inputs '())
                 (search-paths '()))
        (match entries
-         (((name version output item
-                 ('propagated-inputs deps)
-                 ('search-paths paths) _ ...) . rest)
-          (loop (append rest deps)                ;breadth-first traversal
-                (cons item inputs)
-                (append paths search-paths)))
+         (((name version output item fields ...) . rest)
+          (let ((paths search-paths))
+            (let-fields fields (propagated-inputs search-paths properties)
+              (loop (append rest propagated-inputs) ;breadth-first traversal
+                    (cons item inputs)
+                    (append search-paths paths)))))
+         ((('repeated name version item) . rest)
+          (loop rest inputs search-paths))
          (()
           (values (reverse inputs)
                   (delete-duplicates
@@ -212,4 +226,8 @@ search paths of MANIFEST's entries."
     ;; Write 'OUTPUT/etc/profile'.
     (build-etc/profile output search-paths)))
 
+;;; Local Variables:
+;;; eval: (put 'let-fields 'scheme-indent-function 2)
+;;; End:
+
 ;;; profile.scm ends here