transformations: '--with-source' now operates in depth.

The '--with-source' option is the first one that was implemented, and
it's the only one that would operate only on leaf packages rather than
traversing the dependency graph.  This change makes it consistent with
the rest of the transformation options.

* guix/transformations.scm (evaluate-source-replacement-specs): New
procedure.
(transform-package-source): Rewrite using it.
* tests/transformations.scm ("options->transformation, with-source, no
matches"): Rewrite since we no longer get a warning.
("options->transformation, with-source, in depth"): New test.
* doc/guix.texi (Package Transformation Options): Adjust examples.

1 files changed, 39 insertions, 35 deletions

diff --git a/guix/transformations.scm b/guix/transformations.scm
index 411c4014cb..be2d31b8c7 100644
--- a/guix/transformations.scm
+++ b/guix/transformations.scm
@@ -129,42 +129,46 @@ the new package's version number from URI."
 ;;; Transformations.
 ;;;
 
-(define (transform-package-source sources)
-  "Return a transformation procedure that replaces package sources with the
-matching URIs given in SOURCES."
-  (define new-sources
-    (map (lambda (uri)
-           (match (string-index uri #\=)
-             (#f
-              ;; Determine the package name and version from URI.
-              (call-with-values
-                  (lambda ()
-                    (hyphen-package-name->name+version
-                     (tarball-base-name (basename uri))))
-                (lambda (name version)
-                  (list name version uri))))
-             (index
-              ;; What's before INDEX is a "PKG@VER" or "PKG" spec.
-              (call-with-values
-                  (lambda ()
-                    (package-name->name+version (string-take uri index)))
-                (lambda (name version)
-                  (list name version
-                        (string-drop uri (+ 1 index))))))))
-         sources))
+(define (evaluate-source-replacement-specs specs)
+  "Parse SPECS, a list of strings like \"guile=/tmp/guile-4.2.tar.gz\" or just
+\"/tmp/guile-4.2.tar.gz\" and return a list of package spec/procedure pairs as
+expected by 'package-input-rewriting/spec'.  Raise an error if an element of
+SPECS uses invalid syntax."
+  (define not-equal
+    (char-set-complement (char-set #\=)))
 
-  (lambda (obj)
-    (let loop ((sources  new-sources)
-               (result   '()))
-      (match obj
-        ((? package? p)
-         (match (assoc-ref sources (package-name p))
-           ((version source)
-            (package-with-source p source version))
-           (#f
-            p)))
-        (_
-         obj)))))
+  (map (lambda (spec)
+         (match (string-tokenize spec not-equal)
+           ((uri)
+            (let* ((base (tarball-base-name (basename uri)))
+                   (name (hyphen-package-name->name+version base)))
+              (cons name
+                    (lambda (old)
+                      (package-with-source old uri)))))
+           ((spec uri)
+            (let-values (((name version)
+                          (package-name->name+version spec)))
+              ;; Note: Here VERSION is used as the version string of the new
+              ;; package rather than as part of the spec of the package being
+              ;; targeted.
+              (cons name
+                    (lambda (old)
+                      (package-with-source old uri version)))))
+           (_
+            (raise (formatted-message
+                    (G_ "invalid source replacement specification: ~s")
+                    spec)))))
+       specs))
+
+(define (transform-package-source replacement-specs)
+  "Return a transformation procedure that replaces package sources with the
+matching URIs given in REPLACEMENT-SPECS."
+  (let* ((replacements (evaluate-source-replacement-specs replacement-specs))
+         (rewrite      (package-input-rewriting/spec replacements)))
+    (lambda (obj)
+      (if (package? obj)
+          (rewrite obj)
+          obj))))
 
 (define (evaluate-replacement-specs specs proc)
   "Parse SPECS, a list of strings like \"guile=guile@2.1\" and return a list