Fixes <https://issues.guix.gnu.org/57093>.
Reported by Mohammed AMAR-BENSABER <renken@shione.net>.
Previously 'read-with-comments' would enter an infinite loop.
* guix/read-print.scm (read-with-comments)[missing-closing-paren-error]:
New procedure.
Call it when 'loop' as called from 'liip' returns EOF.
* tests/read-print.scm ("read-with-comments: missing closing paren"):
New test.
* guix/read-print.scm (%not-newline): New variable.
(print-multi-line-comment): New procedure.
(pretty-print-with-comments): Use it.
* tests/read-print.scm ("pretty-print-with-comments, multi-line
comment"): New test.
This lets users use three leading semicolons, for instance, in top-level
comments.
* guix/read-print.scm (canonicalize-comment): Add INDENT parameter and
honor it.
(pretty-print-with-comments): Change default value of #:format-comment.
Call FORMAT-COMMENT with INDENT as the second argument.
* tests/read-print.scm: Adjust test accordingly.
* guix/read-print.scm (read-with-comments): Add #:blank-line? and honor it.
(read-with-comments/sequence, pretty-print-with-comments/splice): New
procedures.
* tests/read-print.scm (test-pretty-print/sequence): New macro.
Add tests using it.
* guix/read-print.scm (<page-break>, page-break?, page-break)
(char-set:whitespace-sans-page-break): New variables.
(space?): New procedure.
(read-vertical-space): Use it.
(read-until-end-of-line): New procedure.
(read-with-comments): Add #\page case.
(pretty-print-with-comments): Add 'page-break?' case.
* tests/read-print.scm ("read-with-comments: top-level page break"): New
test.
Add round-trip test with page break within an sexp.
* guix/read-print.scm (<vertical-space>, vertical-space?)
(vertical-space, vertical-space-height): New variables.
(combine-vertical-space, canonicalize-vertical-space)
(read-vertical-space): New procedures.
(read-with-comments): Use it in the #\newline case.
(pretty-print-with-comments): Add #:format-vertical-space and honor it.
Add case for 'vertical-space?'.
* guix/scripts/style.scm (format-package-definition): Pass
#:format-vertical-space to 'object->string*'.
* tests/read-print.scm ("read-with-comments: list with blank line")
("read-with-comments: list with multiple blank lines")
("read-with-comments: top-level blank lines")
("pretty-print-with-comments, canonicalize-vertical-space"): New tests.
Add a couple of additional round-trip tests.
