import: elpa: Improve error message reporting.

* guix/import/elpa.scm (filter-dependencies): Fix bug.
  (call-with-downloaded-file): Add optional parameter 'error-thunk'.
  (fetch-package-description): Use it.
This commit is contained in:
Federico Beffa 2015-07-22 15:26:12 +02:00
parent 23bae7bb86
commit 6544aba5fc

@ -52,7 +52,7 @@ past were distributed separately from Emacs."
(define (filter-dependencies names)
"Remove the package names included with Emacs from the list of
NAMES (strings)."
(filter emacs-standard-library? names))
(filter (compose not emacs-standard-library?) names))
(define (elpa-name->package-name name)
"Given the NAME of an Emacs package, return the corresponding Guix name."
@ -77,14 +77,17 @@ NAMES (strings)."
(call-with-downloaded-file url read)
(leave (_ "~A: currently not supported~%") repo))))
(define (call-with-downloaded-file url proc)
(define* (call-with-downloaded-file url proc #:optional (error-thunk #f))
"Fetch URL, store the content in a temporary file and call PROC with that
file. Returns the value returned by PROC."
file. Returns the value returned by PROC. On error call ERROR-THUNK and
return its value or leave if it's false."
(call-with-temporary-output-file
(lambda (temp port)
(or (and (url-fetch url temp)
(call-with-input-file temp proc))
(error "download failed" url)))))
(if error-thunk
(error-thunk)
(leave (_ "~A: download failed~%") url))))))
(define (is-elpa-package? name elpa-pkg-spec)
"Return true if the string NAME corresponds to the name of the package
@ -158,8 +161,9 @@ include VERSION."
(define (fetch-package-description kind name repo)
"Fetch the description of package NAME of type KIND from REPO."
(let ((url (full-url repo name "-readme.txt")))
(call-with-downloaded-file url read-string)))
(let ((url (full-url repo name "-readme.txt"))
(error-thunk (lambda () "No description available.")))
(call-with-downloaded-file url read-string error-thunk)))
(define* (fetch-elpa-package name #:optional (repo 'gnu))
"Fetch package NAME from REPO."