guix-kreyren/guix/diagnostics.scm
Maxim Cournoyer 53cd5923ef
diagnostics: Fix typo about 0-indexed COL in location.
* guix/diagnostics.scm (source-properties->location): The location column is
0-indexed, not 1-indexed (the same as in source-properties, so the code is
accurate).
2022-05-31 14:52:14 -04:00

384 lines
14 KiB
Scheme
Raw Permalink Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
(define-module (guix diagnostics)
#:use-module (guix colors)
#:use-module (guix i18n)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-9)
#:use-module (srfi srfi-26)
#:use-module (srfi srfi-35)
#:use-module (ice-9 format)
#:use-module (ice-9 match)
#:export (warning
info
report-error
leave
<location>
location
location?
location-file
location-line
location-column
source-properties->location
location->source-properties
location->string
location->hyperlink
&error-location
error-location?
error-location
formatted-message
formatted-message?
formatted-message-string
formatted-message-arguments
&fix-hint
fix-hint?
condition-fix-hint
guix-warning-port
program-name
define-with-syntax-properties))
;;; Commentary:
;;;
;;; This module provides the tools to report diagnostics to the user in a
;;; consistent way: errors, warnings, and notes.
;;;
;;; Code:
(define (trivial-format-string? fmt)
(define len
(string-length fmt))
(let loop ((start 0))
(or (>= (+ 1 start) len)
(let ((tilde (string-index fmt #\~ start)))
(or (not tilde)
(case (string-ref fmt (+ tilde 1))
((#\a #\A #\%) (loop (+ tilde 2)))
(else #f)))))))
(define-syntax highlight-argument
(lambda (s)
"Given FMT and ARG, expand ARG to a call that highlights it, provided FMT
is a trivial format string."
;; Be conservative: limit format argument highlighting to cases where the
;; format string contains nothing but ~a escapes. If it contained ~s
;; escapes, this strategy wouldn't work.
(syntax-case s ()
((_ "~a~%" arg) ;don't highlight whole messages
#'arg)
((_ fmt arg)
(trivial-format-string? (syntax->datum #'fmt))
#'(%highlight-argument arg))
((_ fmt arg)
#'arg))))
(define* (%highlight-argument arg #:optional (port (guix-warning-port)))
"Highlight ARG, a format string argument, if PORT supports colors."
(cond ((string? arg)
;; If ARG contains white space, don't highlight it, on the grounds
;; that it may be a complete message in its own, like those produced
;; by 'guix lint.
(if (string-any char-set:whitespace arg)
arg
(highlight arg port)))
((symbol? arg)
(highlight (symbol->string arg) port))
(else arg)))
(define-syntax define-diagnostic
(syntax-rules ()
"Create a diagnostic macro (i.e., NAME), which will prepend PREFIX to all
messages."
((_ name (G_ prefix) colors)
(define-syntax name
(lambda (x)
(syntax-case x ()
((name location (underscore fmt) args (... ...))
(and (string? (syntax->datum #'fmt))
(free-identifier=? #'underscore #'G_))
#'(begin
(print-diagnostic-prefix prefix location
#:colors colors)
(format (guix-warning-port) (gettext fmt %gettext-domain)
(highlight-argument fmt args) (... ...))))
((name location (N-underscore singular plural n)
args (... ...))
(and (string? (syntax->datum #'singular))
(string? (syntax->datum #'plural))
(free-identifier=? #'N-underscore #'N_))
#'(begin
(print-diagnostic-prefix prefix location
#:colors colors)
(format (guix-warning-port)
(ngettext singular plural n %gettext-domain)
(highlight-argument singular args) (... ...))))
((name (underscore fmt) args (... ...))
(free-identifier=? #'underscore #'G_)
#'(name #f (underscore fmt) args (... ...)))
((name (N-underscore singular plural n)
args (... ...))
(free-identifier=? #'N-underscore #'N_)
#'(name #f (N-underscore singular plural n)
args (... ...)))
(id
(identifier? #'id)
;; Run-time variant.
#'(lambda (location fmt . args)
(emit-diagnostic fmt args
#:location location
#:prefix prefix
#:colors colors)))))))))
;; XXX: This doesn't work well for right-to-left languages.
;; TRANSLATORS: The goal is to emit "warning:" followed by a short phrase;
;; "~a" is a placeholder for that phrase.
(define-diagnostic warning (G_ "warning: ") %warning-color) ;emit a warning
(define-diagnostic info (G_ "") %info-color)
(define-diagnostic report-error (G_ "error: ") %error-color)
(define-syntax-rule (leave args ...)
"Emit an error message and exit."
(begin
(report-error args ...)
(exit 1)))
(define* (emit-diagnostic fmt args
#:key location (colors (color)) (prefix ""))
"Report diagnostic message FMT with the given ARGS and the specified
LOCATION, COLORS, and PREFIX.
This procedure is used as a last resort when the format string is not known at
macro-expansion time."
(print-diagnostic-prefix (gettext prefix %gettext-domain)
location #:colors colors)
(apply format (guix-warning-port) fmt
(if (trivial-format-string? fmt)
(map %highlight-argument args)
args)))
(define %warning-color (color BOLD MAGENTA))
(define %info-color (color BOLD))
(define %error-color (color BOLD RED))
(define* (print-diagnostic-prefix prefix #:optional location
#:key (colors (color)))
"Print PREFIX as a diagnostic line prefix."
(define color?
(color-output? (guix-warning-port)))
(define location-color
(if color?
(cut colorize-string <> (color BOLD))
identity))
(define prefix-color
(if color?
(lambda (prefix)
(colorize-string prefix colors))
identity))
(let ((prefix (if (string-null? prefix)
prefix
(gettext prefix %gettext-domain))))
(if location
(format (guix-warning-port) "~a: ~a"
(location-color
(if (supports-hyperlinks? (guix-warning-port))
(location->hyperlink location)
(location->string location)))
(prefix-color prefix))
(format (guix-warning-port) "~:[~*~;guix ~a: ~]~a"
(program-name) (program-name)
(prefix-color prefix)))))
;; A source location.
(define-record-type <location>
(make-location file line column)
location?
(file location-file) ; file name
(line location-line) ; 1-indexed line
(column location-column)) ; 0-indexed column
(define (location file line column)
"Return the <location> object for the given FILE, LINE, and COLUMN."
(and line column file
(make-location file line column)))
(define (source-properties->location loc)
"Return a location object based on the info in LOC, an alist as returned
by Guile's `source-properties', `frame-source', `current-source-location',
etc."
;; In accordance with the GCS, start line and column numbers at 1. Note
;; that unlike LINE and `port-column', COL is actually 0-indexed here...
(match loc
((('line . line) ('column . col) ('filename . file)) ;common case
(and file line col
(make-location file (+ line 1) col)))
(#f
#f)
(#(file line column)
;; Guile >= 3.0.6 uses vectors instead of alists internally, which can be
;; seen in the arguments to 'syntax-error' exceptions.
(location file (+ 1 line) column))
(_
(let ((file (assq-ref loc 'filename))
(line (assq-ref loc 'line))
(col (assq-ref loc 'column)))
(location file (and line (+ line 1)) col)))))
(define (location->source-properties loc)
"Return the source property association list based on the info in LOC,
a location object."
`((line . ,(and=> (location-line loc) 1-))
(column . ,(location-column loc))
(filename . ,(location-file loc))))
(define (location->string loc)
"Return a human-friendly, GNU-standard representation of LOC."
(match loc
(#f (G_ "<unknown location>"))
(($ <location> file line column)
(format #f "~a:~a:~a" file line column))))
(define (location->hyperlink location)
"Return a string corresponding to LOCATION, with escapes for a hyperlink."
(let ((str (location->string location))
(file (if (string-prefix? "/" (location-file location))
(location-file location)
(search-path %load-path (location-file location)))))
(if file
(file-hyperlink file str)
str)))
(define-condition-type &error-location &error
error-location?
(location error-location)) ;<location>
(define-condition-type &fix-hint &condition
fix-hint?
(hint condition-fix-hint)) ;string
(define-condition-type &formatted-message &error
formatted-message?
(format formatted-message-string)
(arguments formatted-message-arguments))
(define (check-format-string location format args)
"Check that FORMAT, a format string, contains valid escapes, and that the
number of arguments in ARGS matches the escapes in FORMAT."
(define actual-count
(length args))
(define allowed-chars ;for 'simple-format'
'(#\A #\S #\a #\s #\~ #\%))
(define (format-chars fmt)
(let loop ((chars (string->list fmt))
(result '()))
(match chars
(()
(reverse result))
((#\~ opt rest ...)
(loop rest (cons opt result)))
((chr rest ...)
(and (memv chr allowed-chars)
(loop rest result))))))
(match (format-chars format)
(#f
;; XXX: In this case it could be that FMT contains invalid escapes, or it
;; could be that it contains escapes beyond ALLOWED-CHARS, for (ice-9
;; format). Instead of implementing '-Wformat', do nothing.
#f)
(chars
(let ((count (fold (lambda (chr count)
(case chr
((#\~ #\%) count)
(else (+ count 1))))
0
chars)))
(unless (= count actual-count)
(warning location (G_ "format string got ~a arguments, expected ~a~%")
actual-count count))))))
(define-syntax formatted-message
(lambda (s)
"Return a '&formatted-message' error condition."
(syntax-case s (G_)
((_ (G_ str) args ...)
(string? (syntax->datum #'str))
(let ((str (syntax->datum #'str)))
;; Implement a subset of '-Wformat'.
(check-format-string (source-properties->location
(syntax-source s))
str #'(args ...))
(with-syntax ((str (string-append str "\n")))
#'(condition
(&formatted-message (format str)
(arguments (list args ...))))))))))
(define guix-warning-port
(make-parameter (current-warning-port)))
(define program-name
;; Name of the command-line program currently executing, or #f.
(make-parameter #f))
(define-syntax define-with-syntax-properties
(lambda (x)
"Define BINDING to be a syntax form replacing each VALUE-IDENTIFIER and
SYNTAX-PROPERTIES-IDENTIFIER in body by the syntax and syntax-properties,
respectively, of each ensuing syntax object."
(syntax-case x ()
((_ (binding (value-identifier syntax-properties-identifier)
...)
body ...)
(and (and-map identifier? #'(value-identifier ...))
(and-map identifier? #'(syntax-properties-identifier ...)))
#'(define-syntax binding
(lambda (y)
(with-ellipsis :::
(syntax-case y ()
((_ value-identifier ...)
(with-syntax ((syntax-properties-identifier
#`'#,(datum->syntax y
(syntax-source
#'value-identifier)))
...)
#'(begin body ...)))
(_
(syntax-violation #f (format #f
"Expected (~a~{ ~a~})"
'binding
'(value-identifier ...))
y)))))))
(_
(syntax-violation #f "Expected a definition of the form \
(define-with-syntax-properties (binding (value syntax-properties) \
...) body ...)" x)))))