diff options
| -rw-r--r-- | guix/read-print.scm | 54 | ||||
| -rw-r--r-- | guix/scripts/style.scm | 3 | ||||
| -rw-r--r-- | tests/read-print.scm | 76 |
3 files changed, 129 insertions, 4 deletions
diff --git a/guix/read-print.scm b/guix/read-print.scm index 732d0dc1f8..2b626ba281 100644 --- a/guix/read-print.scm +++ b/guix/read-print.scm @@ -30,6 +30,11 @@ blank? + vertical-space + vertical-space? + vertical-space-height + canonicalize-vertical-space + comment comment? comment->string @@ -58,6 +63,26 @@ (define blank? (record-predicate <blank>)) +(define <vertical-space> + (make-record-type '<vertical-space> '(height) + #:parent <blank> + #:extensible? #f)) + +(define vertical-space? (record-predicate <vertical-space>)) +(define vertical-space (record-type-constructor <vertical-space>)) +(define vertical-space-height (record-accessor <vertical-space> 'height)) + +(define (combine-vertical-space x y) + "Return vertical space as high as the combination of X and Y." + (vertical-space (+ (vertical-space-height x) + (vertical-space-height y)))) + +(define canonicalize-vertical-space + (let ((unit (vertical-space 1))) + (lambda (space) + "Return a vertical space corresponding to a single blank line." + unit))) + (define <comment> ;; Comments. (make-record-type '<comment> '(str margin?) @@ -80,6 +105,19 @@ end with newline, otherwise an error is raised." (&message (message "invalid comment string"))))) (string->comment str margin?)) +(define (read-vertical-space port) + "Read from PORT until a non-vertical-space character is met, and return a +single <vertical-space> record." + (define (space? chr) + (char-set-contains? char-set:whitespace chr)) + + (let loop ((height 1)) + (match (read-char port) + (#\newline (loop (+ 1 height))) + ((? eof-object?) (vertical-space height)) + ((? space?) (loop height)) + (chr (unread-char chr port) (vertical-space height))))) + (define (read-with-comments port) "Like 'read', but include <blank> objects when they're encountered." ;; Note: Instead of implementing this functionality in 'read' proper, which @@ -107,7 +145,9 @@ end with newline, otherwise an error is raised." eof) ;oops! (chr (cond ((eqv? chr #\newline) - (loop #t return)) + (if blank-line? + (read-vertical-space port) + (loop #t return))) ((char-set-contains? char-set:whitespace chr) (loop blank-line? return)) ((memv chr '(#\( #\[)) @@ -297,6 +337,7 @@ semicolons." (define* (pretty-print-with-comments port obj #:key (format-comment identity) + (format-vertical-space identity) (indent 0) (max-width 78) (long-list 5)) @@ -306,7 +347,8 @@ included in the output. Lists longer than LONG-LIST are written as one element per line. Comments are passed through FORMAT-COMMENT before being emitted; a useful value for -FORMAT-COMMENT is 'canonicalize-comment'." +FORMAT-COMMENT is 'canonicalize-comment'. Vertical space is passed through +FORMAT-VERTICAL-SPACE; a useful value of 'canonicalize-vertical-space'." (define (list-of-lists? head tail) ;; Return true if HEAD and TAIL denote a list of lists--e.g., a list of ;; 'let' bindings. @@ -394,6 +436,14 @@ FORMAT-COMMENT is 'canonicalize-comment'." port))) (display (make-string indent #\space) port) indent) + ((? vertical-space? space) + (unless delimited? (newline port)) + (let loop ((i (vertical-space-height (format-vertical-space space)))) + (unless (zero? i) + (newline port) + (loop (- i 1)))) + (display (make-string indent #\space) port) + indent) (('quote lst) (unless delimited? (display " " port)) (display "'" port) diff --git a/guix/scripts/style.scm b/guix/scripts/style.scm index 5c0ecc0896..2e14bc68fd 100644 --- a/guix/scripts/style.scm +++ b/guix/scripts/style.scm @@ -316,7 +316,8 @@ PACKAGE." (object->string* exp (location-column (package-definition-location package)) - #:format-comment canonicalize-comment))))) + #:format-comment canonicalize-comment + #:format-vertical-space canonicalize-vertical-space))))) (define (package-location<? p1 p2) "Return true if P1's location is \"before\" P2's." diff --git a/tests/read-print.scm b/tests/read-print.scm index e9ba1127d4..f915b7e2d2 100644 --- a/tests/read-print.scm +++ b/tests/read-print.scm @@ -19,7 +19,8 @@ (define-module (tests-style) #:use-module (guix read-print) #:use-module (guix gexp) ;for the reader extensions - #:use-module (srfi srfi-64)) + #:use-module (srfi srfi-64) + #:use-module (ice-9 match)) (define-syntax-rule (test-pretty-print str args ...) "Test equality after a round-trip where STR is passed to @@ -40,6 +41,35 @@ (call-with-input-string "(a . b)" read-with-comments)) +(test-equal "read-with-comments: list with blank line" + `(list with ,(vertical-space 1) blank line) + (call-with-input-string "\ +(list with + + blank line)\n" + read-with-comments)) + +(test-equal "read-with-comments: list with multiple blank lines" + `(list with ,(comment ";multiple\n" #t) + ,(vertical-space 3) blank lines) + (call-with-input-string "\ +(list with ;multiple + + + + blank lines)\n" + read-with-comments)) + +(test-equal "read-with-comments: top-level blank lines" + (list (vertical-space 2) '(a b c) (vertical-space 2)) + (call-with-input-string " + +(a b c)\n\n" + (lambda (port) + (list (read-with-comments port) + (read-with-comments port) + (read-with-comments port))))) + (test-pretty-print "(list 1 2 3 4)") (test-pretty-print "((a . 1) (b . 2))") (test-pretty-print "(a b c . boom)") @@ -181,6 +211,24 @@ mnopqrstuvwxyz.\")" `(cons \"--without-any-problem\" ,flags)))") +(test-pretty-print "\ +(vertical-space one: + + two: + + + three: + + + + end)") + +(test-pretty-print "\ +(vertical-space one + + ;; Comment after blank line. + two)") + (test-equal "pretty-print-with-comments, canonicalize-comment" "\ (list abc @@ -206,4 +254,30 @@ mnopqrstuvwxyz.\")" #:format-comment canonicalize-comment))))) +(test-equal "pretty-print-with-comments, canonicalize-vertical-space" + "\ +(list abc + + def + + ;; last one + ghi)" + (let ((sexp (call-with-input-string + "\ +(list abc + + + + def + + +;; last one + ghi)" + read-with-comments))) + (call-with-output-string + (lambda (port) + (pretty-print-with-comments port sexp + #:format-vertical-space + canonicalize-vertical-space))))) + (test-end) |