(address . guix-patches@gnu.org)(address . mbakke@fastmail.com)
20200630220913.14665-1-kuba@kadziolka.net
* guix/build/utils.scm (substitute, substitute*)[require-matches?]: New
argument.
---
Of course, this will require some changes in the build recipes. However,
many of the bugs I have seen before could've been prevented by this
behavior, so I believe it is worth it.
I am currently running 'guix build hello' with these changes; I will
send any follow-up fixes needed to this bug#.
guix/build/utils.scm | 47 +++++++++++++++++++++++++++++++++-----------
1 file changed, 35 insertions(+), 12 deletions(-)
Toggle diff (96 lines)
diff --git a/guix/build/utils.scm b/guix/build/utils.scm
index dc55c6745d..1bfb774c60 100644
--- a/guix/build/utils.scm
+++ b/guix/build/utils.scm
@@ -6,6 +6,7 @@
;;; Copyright © 2018 Arun Isaac <arunisaac@systemreboot.net>
;;; Copyright © 2018, 2019 Ricardo Wurmus <rekado@elephly.net>
;;; Copyright © 2020 Efraim Flashner <efraim@flashner.co.il>
+;;; Copyright © 2020 Jakub Kądziołka <kuba@kadziolka.net>
;;;
;;; This file is part of GNU Guix.
;;;
@@ -747,29 +748,42 @@ PROC's result is returned."
(lambda (key . args)
(false-if-exception (delete-file template))))))
-(define (substitute file pattern+procs)
+(define* (substitute file pattern+procs #:key (require-matches? #t))
"PATTERN+PROCS is a list of regexp/two-argument-procedure pairs. For each
line of FILE, and for each PATTERN that it matches, call the corresponding
PROC as (PROC LINE MATCHES); PROC must return the line that will be written as
a substitution of the original line. Be careful about using '$' to match the
-end of a line; by itself it won't match the terminating newline of a line."
- (let ((rx+proc (map (match-lambda
- (((? regexp? pattern) . proc)
- (cons pattern proc))
- ((pattern . proc)
- (cons (make-regexp pattern regexp/extended)
- proc)))
- pattern+procs)))
+end of a line; by itself it won't match the terminating newline of a line.
+
+By default, SUBSTITUTE will raise a &message condition if one of the patterns
+fails to match. If a lack of matches is acceptable, pass #:require-matches? #f
+to disable this check."
+ (let ((rx+proc (map (match-lambda
+ (((? regexp? pattern) . proc)
+ (cons* #f "<unknown>" pattern proc))
+ ((pattern . proc)
+ (cons* #f pattern (make-regexp pattern regexp/extended)
+ proc)))
+ pattern+procs)))
(with-atomic-file-replacement file
(lambda (in out)
(let loop ((line (read-line in 'concat)))
(if (eof-object? line)
- #t
+ (when require-matches?
+ (for-each
+ (match-lambda
+ ((#f pat . _)
+ (raise (condition
+ (&message
+ (message (format #f "substitute: ~a: pattern failed to match: ~a" file pat))))))
+ ((#t . _) #t))
+ rx+proc))
(let ((line (fold (lambda (r+p line)
(match r+p
- ((regexp . proc)
+ ((_ _ regexp . proc)
(match (list-matches regexp line)
((and m+ (_ _ ...))
+ (set-car! r+p #t)
(proc line m+))
(_ line)))))
line
@@ -814,9 +828,17 @@ match substring.
Alternatively, FILE may be a list of file names, in which case they are
all subject to the substitutions.
+By default, SUBSTITUTE* will raise a &message condition if one of the patterns
+fails to match on one of the files. If a lack of matches is acceptable,
+add #:require-matches? #f after FILE to disable this check.
+
Be careful about using '$' to match the end of a line; by itself it won't
match the terminating newline of a line."
((substitute* file ((regexp match-var ...) body ...) ...)
+ (substitute* file #:require-matches? #t
+ ((regexp match-var ...) body ...) ...))
+ ((substitute* file #:require-matches? require-matches?
+ ((regexp match-var ...) body ...) ...)
(let ()
(define (substitute-one-file file-name)
(substitute
@@ -840,7 +862,8 @@ match the terminating newline of a line."
(begin body ...)
(substring l o (match:start m))
r))))))))
- ...)))
+ ...)
+ #:require-matches? require-matches?))
(match file
((files (... ...))
--
2.26.2