apteryx pushed a commit to branch master
in repository guix.
commit 9b7213fc11bdefb884c4c23d1e853ea92b40239f
Author: Sergey Trofimov <[email protected]>
AuthorDate: Mon May 19 11:50:08 2025 +0200
gexp: Allow file-unions with dangling symlinks.
* guix/gexp.scm (file-union): Add #:dangling-symlinks? parameter.
Change-Id: I09d44ec785fd7141b02dee2d8dc23ccc499aa933
Signed-off-by: Maxim Cournoyer <[email protected]>
---
doc/guix.texi | 12 +++++++-----
guix/gexp.scm | 47 ++++++++++++++++++++++++-----------------------
2 files changed, 31 insertions(+), 28 deletions(-)
diff --git a/doc/guix.texi b/doc/guix.texi
index fd86551787..ef8504bb3e 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -12673,11 +12673,13 @@ as in:
This is the declarative counterpart of @code{text-file*}.
@end deffn
-@deffn {Procedure} file-union name files
-Return a @code{<computed-file>} that builds a directory containing all of
@var{files}.
-Each item in @var{files} must be a two-element list where the first element is
the
-file name to use in the new directory, and the second element is a gexp
-denoting the target file. Here's an example:
+@deffn {Procedure} file-union name files [#:dangling-symlinks? #f]
+Return a @code{<computed-file>} that builds a directory containing all
+of @var{files}. Each item in @var{files} must be a two-element list
+where the first element is the file name to use in the new directory,
+and the second element is a gexp denoting the target file.
+@code{#:dangling-symlinks?} controls if gexps must lower to an existing
+file. Here's an example:
@lisp
(file-union "etc"
diff --git a/guix/gexp.scm b/guix/gexp.scm
index 8dd746eee0..302a1bb553 100644
--- a/guix/gexp.scm
+++ b/guix/gexp.scm
@@ -2144,7 +2144,7 @@ This is the declarative counterpart of 'text-file*'."
(computed-file name build #:guile guile))
-(define* (file-union name files #:key guile)
+(define* (file-union name files #:key guile dangling-symlinks?)
"Return a <computed-file> that builds a directory containing all of FILES.
Each item in FILES must be a two-element list where the first element is the
file name to use in the new directory, and the second element is a gexp
@@ -2158,28 +2158,29 @@ denoting the target file. Here's an example:
(\"libvirt/qemu.conf\" ,(plain-file \"qemu.conf\" \"\"))))
This yields an 'etc' directory containing these two files."
- (computed-file name
- (with-imported-modules '((guix build utils))
- (gexp
- (begin
- (use-modules (guix build utils))
-
- (mkdir (ungexp output))
- (chdir (ungexp output))
- (ungexp-splicing
- (map (match-lambda
- ((target source)
- (gexp
- (begin
- ;; Stat the source to abort early if it does
- ;; not exist.
- (stat (ungexp source))
-
- (mkdir-p (dirname (ungexp target)))
- (symlink (ungexp source)
- (ungexp target))))))
- files)))))
- #:guile guile))
+ (computed-file
+ name
+ (with-imported-modules '((guix build utils))
+ (gexp
+ (begin
+ (use-modules (guix build utils))
+
+ (mkdir (ungexp output))
+ (chdir (ungexp output))
+ (ungexp-splicing
+ (map (match-lambda
+ ((target source)
+ (gexp
+ (let ((source (ungexp source))
+ (target (ungexp target)))
+ (unless (or (ungexp dangling-symlinks?)
+ (stat source #f))
+ (error (format #f "~a points to inexistent file \
+or dangling symlink ~a" target source)))
+ (mkdir-p (dirname target))
+ (symlink source target)))))
+ files)))))
+ #:guile guile))
(define* (directory-union name things
#:key (copy? #f) (quiet? #f)
