;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2015 Federico Beffa <beffa@fbengineering.ch>
;;; Copyright © 2018 Ricardo Wurmus <rekado@elephly.net>
;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
;;;
;;; 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 import cabal)
#:use-module (ice-9 match)
#:use-module (ice-9 regex)
#:use-module (ice-9 rdelim)
#:use-module (srfi srfi-26)
#:use-module (srfi srfi-34)
#:use-module (srfi srfi-35)
#:use-module (srfi srfi-11)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-9)
#:use-module (srfi srfi-9 gnu)
#:use-module (system base lalr)
#:use-module (rnrs enums)
#:use-module (guix utils)
#:export (read-cabal
eval-cabal
cabal-custom-setup-dependencies
cabal-package?
cabal-package-name
cabal-package-version
cabal-package-revision
cabal-package-license
cabal-package-home-page
cabal-package-source-repository
cabal-package-synopsis
cabal-package-description
cabal-package-executables
cabal-package-library
cabal-package-test-suites
cabal-package-flags
cabal-package-eval-environment
cabal-package-custom-setup
cabal-source-repository?
cabal-source-repository-use-case
cabal-source-repository-type
cabal-source-repository-location
cabal-flag?
cabal-flag-name
cabal-flag-description
cabal-flag-default
cabal-flag-manual
cabal-dependency?
cabal-dependency-name
cabal-dependency-version
cabal-executable?
cabal-executable-name
cabal-executable-dependencies
cabal-library?
cabal-library-name
cabal-library-dependencies
cabal-test-suite?
cabal-test-suite-name
cabal-test-suite-dependencies))
;; Part 1:
;;
;; Functions used to read a Cabal file.
;; Comment:
;;
;; The use of virtual closing braces VCCURLY and some lexer functions were
;; inspired from http://hackage.haskell.org/package/haskell-src
;; Object containing information about the structure of a block: (i) delimited
;; by braces or by indentation, (ii) minimum indentation.
(define-record-type <parse-context>
(make-parse-context mode indentation)
parse-context?
(mode parse-context-mode) ; 'layout or 'no-layout
(indentation parse-context-indentation)) ; #f for 'no-layout
;; <parse-context> mode set universe
(define-enumeration context (layout no-layout) make-context)
(define (make-stack)
"Creates a simple stack closure. Actions on the generated stack are
requested by calling it with one of the following symbols as the first
argument: 'empty?, 'push!, 'top, 'pop! and 'clear!. The action 'push! is the
only one requiring a second argument corresponding to the object to be added
to the stack."
(let ((stack '()))
(lambda (msg . args)
(cond ((eqv? msg 'empty?) (null? stack))
((eqv? msg 'push!) (set! stack (cons (first args) stack)))
((eqv? msg 'top) (if (null? stack) '() (first stack)))
((eqv? msg 'pop!) (match stack
((e r ...) (set! stack (cdr stack)) e)
(_ #f)))
((eqv? msg 'clear!) (set! stack '()))
(else #f)))))
;; Stack to track the structure of nested blocks and simple interface
(define context-stack (make-parameter (make-stack)))
(define (context-stack-empty?) ((context-stack) 'empty?))
(define (context-stack-push! e) ((context-stack) 'push! e))
(define (context-stack-top) ((context-stack) 'top))
(define (context-stack-pop!) ((context-stack) 'pop!))
(define (context-stack-clear!) ((context-stack) 'clear!))
;; Indentation of the line being parsed.
(define current-indentation (make-parameter 0))
;; Signal to reprocess the beginning of line, in case we need to close more
;; than one indentation level.
(define check-bol? (make-parameter #f))
;; Name of the file being parsed. Used in error messages.
(define cabal-file-name (make-parameter "unknowk"))
;; Specify the grammar of a Cabal file and generate a suitable syntax analyser.
(define (make-cabal-parser)
"Generate a parser for Cabal files."
(lalr-parser
;; --- token definitions
(CCURLY VCCURLY OPAREN CPAREN TEST ID VERSION RELATION TRUE FALSE -ANY -NONE
(right: IF FLAG EXEC TEST-SUITE CUSTOM-SETUP SOURCE-REPO BENCHMARK LIB COMMON OCURLY)
(left: OR)
(left: PROPERTY AND)
(right: ELIF ELSE NOT))
;; --- rules
(body (properties sections) : (append $1 $2))
(sections (sections flags) : (append $1 $2)
(sections source-repo) : (append $1 (list $2))
(sections executables) : (append $1 $2)
(sections test-suites) : (append $1 $2)
(sections common) : (append $1 $2)
(sections custom-setup) : (append $1 $2)
(sections benchmarks) : (append $1 $2)
(sections lib-sec) : (append $1 (list $2))
() : '())
(flags (flags flag-sec) : (append $1 (list $2))
(flag-sec) : (list $1))
(flag-sec (FLAG OCURLY properties CCURLY) : `(section flag ,$1 ,$3)
(FLAG open properties close) : `(section flag ,$1 ,$3)
(FLAG) : `(section flag ,$1 '()))
(source-repo (SOURCE-REPO OCURLY properties CCURLY)
: `(section source-repository ,$1 ,$3)
(SOURCE-REPO open properties close)
: `(section source-repository ,$1 ,$3))
(properties (properties PROPERTY) : (append $1 (list $2))
(PROPERTY) : (list $1))
(executables (executables exec-sec) : (append $1 (list $2))
(exec-sec) : (list $1))
(exec-sec (EXEC OCURLY exprs CCURLY) : `(section executable ,$1 ,$3)
(EXEC open exprs close) : `(section executable ,$1 ,$3))
(test-suites (test-suites ts-sec) : (append $1 (list $2))
(ts-sec) : (list $1))
(ts-sec (TEST-SUITE OCURLY exprs CCURLY) : `(section test-suite ,$1 ,$3)
(TEST-SUITE open exprs close) : `(section test-suite ,$1 ,$3))
(common (common common-sec) : (append $1 (list $2))
(common-sec) : (list $1))
(common-sec (COMMON OCURLY exprs CCURLY) : `(section common ,$1 ,$3)
(COMMON open exprs close) : `(section common ,$1 ,$3))
(custom-setup (CUSTOM-SETUP exprs) : (list `(section custom-setup ,$1 ,$2)))
(benchmarks (benchmarks bm-sec) : (append $1 (list $2))
(bm-sec) : (list $1))
(bm-sec (BENCHMARK OCURLY exprs CCURLY) : `(section benchmark ,$1 ,$3)
(BENCHMARK open exprs close) : `(section benchmark ,$1 ,$3))
(lib-sec (LIB OCURLY exprs CCURLY) : `(section library ,$1 ,$3)
(LIB open exprs close) : `(section library ,$1 ,$3))
(exprs (exprs PROPERTY) : (append $1 (list $2))
(PROPERTY) : (list $1)
(exprs elif-else) : (append $1 (list ($2 '(()))))
(elif-else) : (list ($1 '(()))))
;; LALR(1) parsers prefer to be left-recursive, which make if-statements slightly involved.
;; XXX: This technically allows multiple else statements.
(elif-else (elif-else ELIF tests OCURLY exprs CCURLY) : (lambda (y) ($1 (list (append (list 'if $3 $5) y))))
(elif-else ELIF tests open exprs close) : (lambda (y) ($1 (list (append (list 'if $3 $5) y))))
(elif-else ELSE OCURLY exprs CCURLY) : (lambda (y) ($1 (list $4)))
;; The 'open' token after 'tests' is shifted after an 'exprs'
;; is found. This is because, instead of 'exprs' a 'OCURLY'
;; token is a valid alternative. For this reason, 'open'
;; pushes a <parse-context> with a line indentation equal to
;; the indentation of 'exprs'.
;;
;; Differently from this, without the rule above this
;; comment, when an 'ELSE' token is found, the 'open' token
;; following the 'ELSE' would be shifted immediately, before
;; the 'exprs' is found (because there are no other valid
;; tokens). The 'open' would therefore create a
;; <parse-context> with the indentation of 'ELSE' and not
;; 'exprs', creating an inconsistency. We therefore allow
;; mixed style conditionals.
(elif-else ELSE open exprs close) : (lambda (y) ($1 (list $4)))
;; Terminating rule.
(if-then) : (lambda (y) (append $1 y)))
(if-then (IF tests OCURLY exprs CCURLY) : (list 'if $2 $4)
(IF tests open exprs close) : (list 'if $2 $4))
(tests (TEST OPAREN ID CPAREN) : `(,$1 ,$3)
(TRUE) : 'true
(FALSE) : 'false
(TEST OPAREN ID RELATION VERSION CPAREN)
: `(,$1 ,(string-append $3 " " $4 " " $5))
(TEST OPAREN ID -ANY CPAREN)
: `(,$1 ,(string-append $3 " -any"))
(TEST OPAREN ID -NONE CPAREN)
: `(,$1 ,(string-append $3 " -none"))
(TEST OPAREN ID RELATION VERSION AND RELATION VERSION CPAREN)
: `(and (,$1 ,(string-append $3 " " $4 " " $5))
(,$1 ,(string-append $3 " " $7 " " $8)))
(NOT tests) : `(not ,$2)
(tests AND tests) : `(and ,$1 ,$3)
(tests OR tests) : `(or ,$1 ,$3)
(OPAREN tests CPAREN) : $2)
(open () : (context-stack-push!
(make-parse-context (context layout)
(current-indentation))))
(close (VCCURLY))))
(define (peek-next-line-indent port)
"This function can be called when the next character on PORT is #\newline
and returns the indentation of the line starting after the #\newline
character. Discard (and consume) empty and comment lines."
(if (eof-object? (peek-char port))
;; If the file is missing the #\newline on the last line, add it and act
;; as if it were there. This is needed for proper operation of
;; indentation based block recognition (based on ‘port-column’).
(begin (unread-char #\newline port) (read-char port) 0)
(let ((initial-newline (string (read-char port))))
(let loop ((char (peek-char port))
(word ""))
(cond ((eqv? char #\newline) (read-char port)
(loop (peek-char port) ""))
((or (eqv? char #\space) (eqv? char #\tab))
(let ((c (read-char port)))
(loop (peek-char port) (string-append word (string c)))))
((comment-line port char) (loop (peek-char port) ""))
(else
(let ((len (string-length word)))
(unread-string (string-append initial-newline word) port)
len)))))))
(define* (read-value port value min-indent #:optional (separator " "))
"The next character on PORT must be #\newline. Append to VALUE the
following lines with indentation larger than MIN-INDENT."
(let loop ((val (string-trim-both value))
(x (peek-next-line-indent port)))
(if (> x min-indent)
(begin
(read-char port) ; consume #\newline
(loop (string-append
val (if (string-null? val) "" separator)
(string-trim-both (read-delimited "\n" port 'peek)))
(peek-next-line-indent port)))
val)))
(define* (read-braced-value port)
"Read up to a closing brace."
(string-trim-both (read-delimited "}" port 'trim)))
(define (lex-white-space port bol)
"Consume white spaces and comment lines on PORT. If a new line is started return #t,
otherwise return BOL (beginning-of-line)."
(let loop ((c (peek-char port))
(bol bol))
(cond
((and (not (eof-object? c))
(or (char=? c #\space) (char=? c #\tab)))
(read-char port)
(loop (peek-char port) bol))
((and (not (eof-object? c)) (char=? c #\newline))
(read-char port)
(loop (peek-char port) #t))
((comment-line port c)
(lex-white-space port bol))
(else
bol))))
(define (lex-bol port)
"Process the beginning of a line on PORT: update current-indentation and
check the end of an indentation based context."
(let ((loc (make-source-location (cabal-file-name) (port-line port)
(port-column port) -1 -1)))
(current-indentation (source-location-column loc))
(case (get-offside port)
((less-than)
(check-bol? #t) ; need to check if closing more than 1 indent level.
(unless (context-stack-empty?) (context-stack-pop!))
(make-lexical-token 'VCCURLY loc #f))
(else
(lex-token port)))))
(define (bol? port) (or (check-bol?) (= (port-column port) 0)))
(define (comment-line port c)
"If PORT starts with a comment line, consume it up to, but not including
#\newline. C is the next character on PORT."
(cond ((and (not (eof-object? c)) (char=? c #\-))
(read-char port)
(let ((c2 (peek-char port)))
(if (char=? c2 #\-)
(read-delimited "\n" port 'peek)
(begin (unread-char c port) #f))))
(else #f)))
(define-enumeration ordering (less-than equal greater-than) make-ordering)
(define (get-offside port)
"In an indentation based context return the symbol 'greater-than, 'equal or
'less-than to signal if the current column number on PORT is greater-, equal-,
or less-than the indentation of the current context."
(let ((x (port-column port)))
(match (context-stack-top)
(($ <parse-context> 'layout indentation)
(cond
((> x indentation) (ordering greater-than))
((= x indentation) (ordering equal))
(else (ordering less-than))))
(_ (ordering greater-than)))))
;; (Semi-)Predicates for individual tokens.
(define (is-relation? c)
(and (char? c) (any (cut char=? c <>) '(#\< #\> #\=))))
(define* (make-rx-matcher pat #:optional (flag #f))
"Compile PAT into a regular expression with FLAG and creates a function
matching a string against the created regexp."
(let ((rx (if flag
(make-regexp pat flag)
(make-regexp pat))))
(cut regexp-exec rx <>)))
(define is-layout-property (make-rx-matcher "([a-z0-9-]+)[ \t]*:[ \t]*(\\w?[^{}]*)"
regexp/icase))
(define is-braced-property (make-rx-matcher "([a-z0-9-]+)[ \t]*:[ \t]*\\{[ \t]*$"
regexp/icase))
(define is-flag (make-rx-matcher "^flag +([a-z0-9_-]+)"
regexp/icase))
(define is-src-repo
(make-rx-matcher "^source-repository +([a-z0-9_-]+)"
regexp/icase))
(define is-exec (make-rx-matcher "^executable +([a-z0-9_-]+)"
regexp/icase))
(define is-test-suite (make-rx-matcher "^test-suite +([a-z0-9_-]+)"
regexp/icase))
(define is-common (make-rx-matcher "^common +([a-z0-9_-]+)"
regexp/icase))
(define is-custom-setup (make-rx-matcher "^(custom-setup)"
regexp/icase))
(define is-benchmark (make-rx-matcher "^benchmark +([a-z0-9_-]+)"
regexp/icase))
;; Libraries can have optional names since Cabal 2.0.
(define is-lib (make-rx-matcher "^library(\\s+([a-z0-9_-]+))?\\s*" regexp/icase))
(define (is-else s) (string-ci=? s "else"))
(define (is-elif s) (string-ci=? s "elif"))
(define (is-if s) (string-ci=? s "if"))
(define (is-true s) (string-ci=? s "true"))
(define (is-false s) (string-ci=? s "false"))
(define (is-any s) (string-ci=? s "-any"))
(define (is-none s) (string-ci=? s "-none"))
(define (is-and s) (string=? s "&&"))
(define (is-or s) (string=? s "||"))
(define (is-id s port loc)
(let ((cabal-reserved-words
'("if" "else" "elif" "library" "flag" "executable" "test-suite"
"custom-setup" "source-repository" "benchmark" "common"))
(spaces (read-while (cut char-set-contains? char-set:blank <>) port))
(c (peek-char port)))
(unread-string spaces port)
;; Sometimes the name of an identifier is the same as one of the reserved
;; words, which would normally lead to an error, see
;; <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=25138>. Unless the word
;; is at the beginning of a line (excluding whitespace), treat is as just
;; another identifier instead of a reserved word.
(and (or (not (= (source-location-column loc) (current-indentation)))
(every (cut string-ci<> s <>) cabal-reserved-words))
(and (not (char=? (last (string->list s)) #\:))
(not (char=? #\: c))))))
(define (is-test s port)
(let ((tests-rx (make-regexp "os|arch|flag|impl"))
(spaces (read-while (cut char-set-contains? char-set:blank <>) port))
(c (peek-char port)))
(if (and (regexp-exec tests-rx s) (char=? #\( c))
#t
(begin (unread-string spaces port) #f))))
;; Lexers for individual tokens.
(define (lex-relation loc port)
(make-lexical-token 'RELATION loc (read-while is-relation? port)))
(define (lex-version loc port)
(make-lexical-token 'VERSION loc
(read-while (lambda (x)
(or (char-numeric? x)
(char=? x #\*)
(char=? x #\.)))
port)))
(define* (read-while is? port #:optional
(is-if-followed-by? (lambda (c) #f))
(is-allowed-follower? (lambda (c) #f)))
"Read from PORT as long as: (i) either the read character satisfies the
predicate IS?, or (ii) it satisfies the predicate IS-IF-FOLLOWED-BY? and the
character immediately following it satisfies IS-ALLOWED-FOLLOWER?. Returns a
string with the read characters."
(let loop ((c (peek-char port))
(res '()))
(cond ((and (not (eof-object? c)) (is? c))
(let ((c (read-char port)))
(loop (peek-char port) (append res (list c)))))
((and (not (eof-object? c)) (is-if-followed-by? c))
(let ((c (read-char port))
(c2 (peek-char port)))
(if (and (not (eof-object? c2)) (is-allowed-follower? c2))
(loop c2 (append res (list c)))
(begin (unread-char c) (list->string res)))))
(else (list->string res)))))
(define (lex-layout-property k-v-rx-res loc port)
(let ((key (string-downcase (match:substring k-v-rx-res 1)))
(value (match:substring k-v-rx-res 2)))
(make-lexical-token
'PROPERTY loc
(list key `(,(if (eqv? (peek-char port) #\newline) ; The next character
; is not necessarily a newline if a bracket follows the property.
(read-value port value (current-indentation))
value))))))
(define (lex-braced-property k-rx-res loc port)
(let ((key (string-downcase (match:substring k-rx-res 1))))
(make-lexical-token
'PROPERTY loc
(list key `(,(read-braced-value port))))))
(define* (lex-rx-res rx-res token loc #:optional (substring-id 1))
(let* ((match (match:substring rx-res substring-id))
(name (if match (string-downcase match) match)))
(make-lexical-token token loc name)))
(define (lex-flag flag-rx-res loc) (lex-rx-res flag-rx-res 'FLAG loc))
(define (lex-src-repo src-repo-rx-res loc)
(lex-rx-res src-repo-rx-res 'SOURCE-REPO loc))
(define (lex-exec exec-rx-res loc) (lex-rx-res exec-rx-res 'EXEC loc))
(define (lex-test-suite ts-rx-res loc) (lex-rx-res ts-rx-res 'TEST-SUITE loc))
(define (lex-common common-rx-res loc) (lex-rx-res common-rx-res 'COMMON loc))
(define (lex-custom-setup ts-rx-res loc) (lex-rx-res ts-rx-res 'CUSTOM-SETUP loc))
(define (lex-benchmark bm-rx-res loc) (lex-rx-res bm-rx-res 'BENCHMARK loc))
(define (lex-lib lib-rx-res loc) (lex-rx-res lib-rx-res 'LIB loc 2))
(define (lex-else loc) (make-lexical-token 'ELSE loc #f))
(define (lex-elif loc) (make-lexical-token 'ELIF loc #f))
(define (lex-if loc) (make-lexical-token 'IF loc #f))
(define (lex-true loc) (make-lexical-token 'TRUE loc #t))
(define (lex-false loc) (make-lexical-token 'FALSE loc #f))
(define (lex-any loc) (make-lexical-token '-ANY loc #f))
(define (lex-none loc) (make-lexical-token '-NONE loc #f))
(define (lex-and loc) (make-lexical-token 'AND loc #f))
(define (lex-or loc) (make-lexical-token 'OR loc #f))
(define (lex-id w loc) (make-lexical-token 'ID loc w))
(define (lex-test w loc) (make-lexical-token 'TEST loc (string->symbol w)))
;; Lexer for tokens recognizable by single char.
(define* (is-ref-char->token ref-char next-char token loc port
#:optional (hook-fn #f))
"If the next character NEXT-CHAR on PORT is REF-CHAR, then read it,
execute HOOK-FN if it isn't #f and return a lexical token of type TOKEN with
location information LOC."
(cond ((char=? next-char ref-char)
(read-char port)
(when hook-fn (hook-fn))
(make-lexical-token token loc (string next-char)))
(else #f)))
(define (is-ocurly->token c loc port)
(is-ref-char->token #\{ c 'OCURLY loc port
(lambda ()
(context-stack-push! (make-parse-context
(context no-layout) #f)))))
(define (is-ccurly->token c loc port)
(is-ref-char->token #\} c 'CCURLY loc port (lambda () (context-stack-pop!))))
(define (is-oparen->token c loc port)
(is-ref-char->token #\( c 'OPAREN loc port))
(define (is-cparen->token c loc port)
(is-ref-char->token #\) c 'CPAREN loc port))
(define (is-not->token c loc port)
(is-ref-char->token #\! c 'NOT loc port))
(define (is-version? c) (char-numeric? c))
;; Main lexer functions
(define (lex-single-char port loc)
"Process tokens which can be recognised by peeking the next character on
PORT. If no token can be recognized return #f. LOC is the current port
location."
(let* ((c (peek-char port)))
(cond ((eof-object? c) (read-char port) '*eoi*)
((is-ocurly->token c loc port))
((is-ccurly->token c loc port))
((is-oparen->token c loc port))
((is-cparen->token c loc port))
((is-not->token c loc port))
((is-version? c) (lex-version loc port))
((is-relation? c) (lex-relation loc port))
(else
#f))))
(define (lex-word port loc)
"Process tokens which can be recognized by reading the next word form PORT.
LOC is the current port location."
(let* ((w (read-delimited " <>=():\t\n" port 'peek)))
(cond ((is-if w) (lex-if loc))
((is-elif w) (lex-elif loc))
((is-else w) (lex-else loc))
((is-test w port) (lex-test w loc))
((is-true w) (lex-true loc))
((is-false w) (lex-false loc))
((is-any w) (lex-any loc))
((is-none w) (lex-none loc))
((is-and w) (lex-and loc))
((is-or w) (lex-or loc))
((is-id w port loc) (lex-id w loc))
(else (unread-string w port) #f))))
(define (lex-line port loc)
"Process tokens which can be recognised by reading a line from PORT. LOC is
the current port location."
(let* ((s (read-delimited "\n{}" port 'peek)))
(cond
((is-flag s) => (cut lex-flag <> loc))
((is-src-repo s) => (cut lex-src-repo <> loc))
((is-exec s) => (cut lex-exec <> loc))
((is-test-suite s) => (cut lex-test-suite <> loc))
((is-common s) => (cut lex-common <> loc))
((is-custom-setup s) => (cut lex-custom-setup <> loc))
((is-benchmark s) => (cut lex-benchmark <> loc))
((is-lib s) => (cut lex-lib <> loc))
(else (unread-string s port) #f))))
(define (lex-property port loc)
;; Stop reading on a }, so closing brackets (for example during
;; if-clauses) work properly.
(let* ((s (read-delimited "\n}" port 'peek)))
(cond
((is-braced-property s) => (cut lex-braced-property <> loc port))
((is-layout-property s) => (cut lex-layout-property <> loc port))
(else #f))))
(define (lex-token port)
(let* ((loc (make-source-location (cabal-file-name) (port-line port)
(port-column port) -1 -1)))
(or (lex-single-char port loc)
(lex-word port loc)
(lex-line port loc)
(lex-property port loc))))
;; Lexer- and error-function generators
(define (errorp)
"Generates the lexer error function."
(let ((p (current-error-port)))
(lambda (message . args)
(format p "~a" message)
(if (and (pair? args) (lexical-token? (car args)))
(let* ((token (car args))
(source (lexical-token-source token))
(line (source-location-line source))
(column (source-location-column source)))
(format p "~a " (or (lexical-token-value token)
(lexical-token-category token)))
(when (and (number? line) (number? column))
(format p "(at line ~a, column ~a)" (1+ line) column)))
(for-each display args))
(format p "~%"))))
(define (make-lexer port)
"Generate the Cabal lexical analyser reading from PORT."
(let ((p port))
(lambda ()
(let ((bol (lex-white-space p (bol? p))))
(check-bol? #f)
(if bol (lex-bol p) (lex-token p))))))
(define* (read-cabal #:optional (port (current-input-port))
(file-name #f))
"Read a Cabal file from PORT. FILE-NAME is a string used in error messages.
If #f use the function 'port-filename' to obtain it."
(let ((cabal-parser (make-cabal-parser)))
(parameterize ((cabal-file-name
(or file-name (port-filename port) "standard input"))
(current-indentation 0)
(check-bol? #f)
(context-stack (make-stack)))
(cabal-parser (make-lexer port) (errorp)))))
;; Part 2:
;;
;; Evaluate the S-expression returned by 'read-cabal'.
;; This defines the object and interface that we provide to access the Cabal
;; file information. Note that this does not include all the pieces of
;; information of the Cabal file, but only the ones we currently are
;; interested in.
(define-record-type <cabal-package>
(make-cabal-package name version revision license home-page source-repository
synopsis description
executables lib test-suites
flags eval-environment custom-setup)
cabal-package?
(name cabal-package-name)
(version cabal-package-version)
(revision cabal-package-revision)
(license cabal-package-license)
(home-page cabal-package-home-page)
(source-repository cabal-package-source-repository)
(synopsis cabal-package-synopsis)
(description cabal-package-description)
(executables cabal-package-executables)
(lib cabal-package-library) ; 'library' is a Scheme keyword
(test-suites cabal-package-test-suites)
(flags cabal-package-flags)
(eval-environment cabal-package-eval-environment) ; alist
(custom-setup cabal-package-custom-setup))
(set-record-type-printer! <cabal-package>
(lambda (package port)
(format port "#<cabal-package ~a@~a>"
(cabal-package-name package)
(cabal-package-version package))))
(define-record-type <cabal-source-repository>
(make-cabal-source-repository use-case type location)
cabal-source-repository?
(use-case cabal-source-repository-use-case)
(type cabal-source-repository-type)
(location cabal-source-repository-location))
;; We need to be able to distinguish the value of a flag from the Scheme #t
;; and #f values.
(define-record-type <cabal-flag>
(make-cabal-flag name description default manual)
cabal-flag?
(name cabal-flag-name)
(description cabal-flag-description)
(default cabal-flag-default) ; 'true or 'false
(manual cabal-flag-manual)) ; 'true or 'false
(set-record-type-printer! <cabal-flag>
(lambda (package port)
(format port "#<cabal-flag ~a default:~a>"
(cabal-flag-name package)
(cabal-flag-default package))))
(define-record-type <cabal-dependency>
(make-cabal-dependency name version)
cabal-dependency?
(name cabal-dependency-name)
(version cabal-dependency-version))
(define-record-type <cabal-executable>
(make-cabal-executable name dependencies)
cabal-executable?
(name cabal-executable-name)
(dependencies cabal-executable-dependencies)) ; list of <cabal-dependency>
(define-record-type <cabal-library>
(make-cabal-library name dependencies)
cabal-library?
(name cabal-library-name)
(dependencies cabal-library-dependencies)) ; list of <cabal-dependency>
(define-record-type <cabal-test-suite>
(make-cabal-test-suite name dependencies)
cabal-test-suite?
(name cabal-test-suite-name)
(dependencies cabal-test-suite-dependencies)) ; list of <cabal-dependency>
(define-record-type <cabal-custom-setup>
(make-cabal-custom-setup name dependencies)
cabal-custom-setup?
(name cabal-custom-setup-name)
(dependencies cabal-custom-setup-dependencies)) ; list of <cabal-dependency>
(define (cabal-flags->alist flag-list)
"Return an alist associating the flag name to its default value from a
list of <cabal-flag> objects."
(map (lambda (flag) (cons (cabal-flag-name flag) (cabal-flag-default flag)))
flag-list))
(define (eval-cabal cabal-sexp env)
"Given the CABAL-SEXP produced by 'read-cabal', evaluate all conditionals
and return a 'cabal-package' object. The values of all tests can be
overwritten by specifying the desired value in ENV. ENV must be an alist.
The accepted keys are: \"os\", \"arch\", \"impl\" and a name of a flag. The
value associated with a flag has to be either \"true\" or \"false\". The
value associated with other keys has to conform to the Cabal file format
definition."
(define (os name)
(let ((env-os (or (assoc-ref env "os") "linux")))
(string-match env-os name)))
(define (arch name)
(let ((env-arch (or (assoc-ref env "arch") "x86_64")))
(string-match env-arch name)))
(define (comp-name+version haskell)
"Extract the compiler name and version from the string HASKELL."
(let* ((matcher-fn (make-rx-matcher "([a-zA-Z0-9_]+)-([0-9.]+)"))
(name (or (and=> (matcher-fn haskell) (cut match:substring <> 1))
haskell))
(version (and=> (matcher-fn haskell) (cut match:substring <> 2))))
(values name version)))
(define (comp-spec-name+op+version spec)
"Extract the compiler specification from SPEC. Return the compiler name,
the ordering operation and the version."
(let* ((with-ver-matcher-fn (make-rx-matcher
"([a-zA-Z0-9_-]+) *([<>=]+) *([0-9.]+) *"))
(without-ver-matcher-fn (make-rx-matcher "([a-zA-Z0-9_-]+)"))
(without-ver-matcher-fn-2 (make-rx-matcher "([a-zA-Z0-9_-]+) (-any|-none)"))
(name (or (and=> (with-ver-matcher-fn spec)
(cut match:substring <> 1))
(and=> (without-ver-matcher-fn-2 spec)
(cut match:substring <> 1))
(match:substring (without-ver-matcher-fn spec) 1)))
(operator (or (and=> (with-ver-matcher-fn spec)
(cut match:substring <> 2))
(and=> (without-ver-matcher-fn-2 spec)
(cut match:substring <> 2))))
(version (or (and=> (with-ver-matcher-fn spec)
(cut match:substring <> 3))
(and=> (without-ver-matcher-fn-2 spec)
(cut match:substring <> 2)))))
(values name operator version)))
(define (impl haskell)
(let*-values (((comp-name comp-ver)
(comp-name+version (or (assoc-ref env "impl") "ghc")))
((spec-name spec-op spec-ver)
(comp-spec-name+op+version haskell)))
(if (and spec-ver comp-ver)
(cond
((not (string= spec-name comp-name)) #f)
((string= spec-op "==") (string= spec-ver comp-ver))
((string= spec-op ">=") (version>=? comp-ver spec-ver))
((string= spec-op ">") (version>? comp-ver spec-ver))
((string= spec-op "<=") (not (version>? comp-ver spec-ver)))
((string= spec-op "<") (not (version>=? comp-ver spec-ver)))
((string= spec-op "-any") #t)
((string= spec-op "-none") #f)
(else
(raise (condition
(&message (message "Failed to evaluate 'impl' test."))))))
(string-match spec-name comp-name))))
(define (cabal-flags)
(make-cabal-section cabal-sexp 'flag))
(define (flag name)
(let ((value (or (assoc-ref env name)
(assoc-ref (cabal-flags->alist (cabal-flags)) name))))
(if (eq? value 'false) #f #t)))
(define common-stanzas
(filter-map (match-lambda
(('section 'common common-name common)
(cons common-name common))
(_ #f))
cabal-sexp))
(define (eval sexp)
"Given an SEXP and an ENV, return the evaluated (SEXP . ENV)."
(match sexp
(() '())
;; nested 'if'
((('if predicate true-group false-group) rest ...)
(append (if (eval predicate)
(eval true-group)
(eval false-group))
(eval rest)))
(('if predicate true-group false-group)
(if (eval predicate)
(eval true-group)
(eval false-group)))
(('flag name) (flag name))
(('os name) (os name))
(('arch name) (arch name))
(('impl name) (impl name))
('true #t)
('false #f)
(('not name) (not (eval name)))
;; 'and' and 'or' aren't functions, thus we can't use apply
(('and args ...) (fold (lambda (e s) (and e s)) #t (eval args)))
(('or args ...) (fold (lambda (e s) (or e s)) #f (eval args)))
;; no need to evaluate flag parameters
(('section 'flag name parameters)
(list 'section 'flag name parameters))
(('section 'custom-setup parameters)
(list 'section 'custom-setup parameters))
(('section type name parameters)
(list 'section type name (eval parameters)))
(((? string? name) values)
(list name values))
((("import" imports) rest ...)
(eval (append (append-map (cut assoc-ref common-stanzas <>) imports)
rest)))
((element rest ...)
(cons (eval element) (eval rest)))
(_ (raise (condition
(&message (message "Failed to evaluate Cabal file. \
See the manual for limitations.")))))))
(define (cabal-evaluated-sexp->package evaluated-sexp)
(let* ((name (lookup-join evaluated-sexp "name"))
(version (lookup-join evaluated-sexp "version"))
(revision (lookup-join evaluated-sexp "x-revision"))
(license (lookup-join evaluated-sexp "license"))
(home-page (lookup-join evaluated-sexp "homepage"))
(home-page-or-hackage
(if (string-null? home-page)
(string-append "http://hackage.haskell.org/package/" name)
home-page))
(source-repository (make-cabal-section evaluated-sexp
'source-repository))
(synopsis (lookup-join evaluated-sexp "synopsis"))
(description (lookup-join evaluated-sexp "description"))
(executables (make-cabal-section evaluated-sexp 'executable))
(lib (make-cabal-section evaluated-sexp 'library))
(test-suites (make-cabal-section evaluated-sexp 'test-suite))
(flags (make-cabal-section evaluated-sexp 'flag))
(eval-environment '())
(custom-setup (match (make-cabal-section evaluated-sexp 'custom-setup)
((x) x)
(_ #f))))
(make-cabal-package name version revision license home-page-or-hackage
source-repository synopsis description executables lib
test-suites flags eval-environment custom-setup)))
((compose cabal-evaluated-sexp->package eval) cabal-sexp))
(define (make-cabal-section sexp section-type)
"Given an SEXP as produced by 'read-cabal', produce a list of objects
pertaining to SECTION-TYPE sections. SECTION-TYPE must be one of:
'executable, 'flag, 'test-suite, 'custom-setup, 'source-repository or
'library."
(filter-map (cut match <>
(('section (? (cut equal? <> section-type)) name parameters)
(case section-type
((test-suite) (make-cabal-test-suite
name (dependencies parameters)))
((custom-setup) (make-cabal-custom-setup
name (dependencies parameters "setup-depends")))
((executable) (make-cabal-executable
name (dependencies parameters)))
((source-repository) (make-cabal-source-repository
name
(lookup-join parameters "type")
(lookup-join parameters "location")))
((library) (make-cabal-library name
(dependencies parameters)))
((flag)
(let* ((default (lookup-join parameters "default"))
(default-true-or-false
(if (and default (string-ci=? "false" default))
'false
'true))
(description (lookup-join parameters "description"))
(manual (lookup-join parameters "manual"))
(manual-true-or-false
(if (and manual (string-ci=? "true" manual))
'true
'false)))
(make-cabal-flag name description
default-true-or-false
manual-true-or-false)))
(else #f)))
(_ #f))
sexp))
(define* (lookup-join key-values-list key #:optional (delimiter " "))
"Lookup and joint all values pertaining to keys of value KEY in
KEY-VALUES-LIST. The optional DELIMITER is used to specify a delimiter string
to be added between the values found in different key/value pairs."
(string-join
(filter-map (cut match <>
(((? (lambda(x) (equal? x key))) value)
(string-join value delimiter))
(_ #f))
key-values-list)
delimiter))
(define dependency-name-version-rx
(make-regexp "([a-zA-Z0-9_-]+) *(.*)"))
(define* (dependencies key-values-list #:optional (key "build-depends"))
"Return a list of 'cabal-dependency' objects for the dependencies found in
KEY-VALUES-LIST."
(let ((deps (string-tokenize (lookup-join key-values-list key ",")
(char-set-complement (char-set #\,)))))
(map (lambda (d)
(let ((rx-result (regexp-exec dependency-name-version-rx d)))
(make-cabal-dependency
(match:substring rx-result 1)
(match:substring rx-result 2))))
deps)))
;;; cabal.scm ends here