[bug#36048] [PATCH] guix: import: hackage: handle hackage revisions

[Robert Vollmert]

Hackage packages can have metadata revision (cabal-file only)
that aren't reflected in the source archive. haskell-build-system
has support for this, but previously `guix import hackage` would
create a definition based on the new cabal file but building using
the old cabal file.

Compare https://debbugs.gnu.org/cgi/bugreport.cgi?bug=35750.

* guix/import/cabal.scm: Parse `x-revision:` property.
* guix/import/hackage.scm: Compute hash of cabal file, and write
cabal-revision build system arguments.
* guix/tests/hackage.scm: Test import of cabal revision.
---
 guix/import/cabal.scm   |  7 +++--
 guix/import/hackage.scm | 61 ++++++++++++++++++++++++++++++-----------
 tests/hackage.scm       | 46 +++++++++++++++++++++++++++++++
 3 files changed, 96 insertions(+), 18 deletions(-)

diff --git a/guix/import/cabal.scm b/guix/import/cabal.scm
index 1a87be0b00..7dfe771e41 100644
--- a/guix/import/cabal.scm
+++ b/guix/import/cabal.scm
@@ -40,6 +40,7 @@
             cabal-package?
             cabal-package-name
             cabal-package-version
+            cabal-package-revision
             cabal-package-license
             cabal-package-home-page
             cabal-package-source-repository
@@ -638,13 +639,14 @@ If #f use the function 'port-filename' to obtain it."
 ;; information of the Cabal file, but only the ones we currently are
 ;; interested in.
 (define-record-type <cabal-package>
-  (make-cabal-package name version license home-page source-repository
+  (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)
@@ -838,6 +840,7 @@ 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
@@ -856,7 +859,7 @@ See the manual for limitations.")))))))
            (custom-setup (match (make-cabal-section evaluated-sexp 
'custom-setup)
                            ((x) x)
                            (_ #f))))
-      (make-cabal-package name version license home-page-or-hackage
+      (make-cabal-package name version revision license home-page-or-hackage
                           source-repository synopsis description executables 
lib
                           test-suites flags eval-environment custom-setup)))
 
diff --git a/guix/import/hackage.scm b/guix/import/hackage.scm
index 366256b40d..cf8219143a 100644
--- a/guix/import/hackage.scm
+++ b/guix/import/hackage.scm
@@ -117,9 +117,15 @@ version is returned."
           (#f name)
           (m (match:substring m 1)))))))
 
-(define (hackage-fetch name-version)
-  "Return the Cabal file for the package NAME-VERSION, or #f on failure.  If
-the version part is omitted from the package name, then return the latest
+(define (read-cabal-and-hash port)
+  (let-values (((port get-hash) (open-sha256-input-port port)))
+    (cons
+      (read-cabal (canonical-newline-port port))
+      (bytevector->nix-base32-string (get-hash)))))
+
+(define (hackage-fetch-and-hash name-version)
+  "Return the Cabal file and hash for the package NAME-VERSION, or #f on 
failure.
+If the version part is omitted from the package name, then return the latest
 version."
   (guard (c ((and (http-get-error? c)
                   (= 404 (http-get-error-code c)))
@@ -127,10 +133,18 @@ version."
     (let-values (((name version) (package-name->name+version name-version)))
       (let* ((url (hackage-cabal-url name version))
              (port (http-fetch url))
-             (result (read-cabal (canonical-newline-port port))))
+             (result (read-cabal-and-hash port)))
         (close-port port)
         result))))
 
+(define (hackage-fetch name-version)
+  "Return the Cabal file for the package NAME-VERSION, or #f on failure.  If
+the version part is omitted from the package name, then return the latest
+version."
+  (match (hackage-fetch-and-hash name-version)
+         ((cabal . hash) cabal)
+         (_              #f)))
+
 (define string->license
   ;; List of valid values from
   ;; https://www.haskell.org
@@ -198,15 +212,19 @@ package being processed and is used to filter references 
to itself."
                                    (cons own-name ghc-standard-libraries))))
           dependencies))
 
-(define* (hackage-module->sexp cabal #:key (include-test-dependencies? #t))
+(define* (hackage-module->sexp cabal cabal-hash #:key 
(include-test-dependencies? #t))
   "Return the `package' S-expression for a Cabal package.  CABAL is the
-representation of a Cabal file as produced by 'read-cabal'."
+representation of a Cabal file as produced by 'read-cabal'. CABAL-HASH is
+the hash of the Cabal file."
 
   (define name
     (cabal-package-name cabal))
 
   (define version
     (cabal-package-version cabal))
+
+  (define revision
+    (cabal-package-revision cabal))
   
   (define source-url
     (hackage-source-url name version))
@@ -252,9 +270,17 @@ representation of a Cabal file as produced by 
'read-cabal'."
                    (list 'quasiquote inputs))))))
   
   (define (maybe-arguments)
-    (if (not include-test-dependencies?)
-        '((arguments `(#:tests? #f)))
-        '()))
+    (define testargs (if (not include-test-dependencies?)
+                       '(#:tests? #f)
+                       '()))
+    (define revargs  (if (not (string-null? revision))
+                       `(#:cabal-revision (,revision ,cabal-hash))
+                       '()))
+    (define args (append testargs revargs))
+    (if (not (nil? args))
+      (let ((qargs `(,'quasiquote ,args)))
+        `((arguments ,qargs)))
+      '()))
 
   (let ((tarball (with-store store
                    (download-to-store store source-url))))
@@ -294,13 +320,16 @@ symbol 'true' or 'false'.  The value associated with 
other keys has to conform
 to the Cabal file format definition.  The default value associated with the
 keys \"os\", \"arch\" and \"impl\" is \"linux\", \"x86_64\" and \"ghc\"
 respectively."
-  (let ((cabal-meta (if port
-                        (read-cabal (canonical-newline-port port))
-                        (hackage-fetch package-name))))
-    (and=> cabal-meta (compose (cut hackage-module->sexp <>
-                                    #:include-test-dependencies?
-                                    include-test-dependencies?)
-                               (cut eval-cabal <> cabal-environment)))))
+  (match
+    (if port (read-cabal-and-hash port)
+             (hackage-fetch-and-hash package-name))
+    ((cabal-meta . cabal-hash)
+     (and=> cabal-meta (compose (cut hackage-module->sexp <>
+                                     cabal-hash
+                                     #:include-test-dependencies?
+                                     include-test-dependencies?)
+                                (cut eval-cabal <> cabal-environment))))
+    (_ #f)))
 
 (define hackage->guix-package/m                   ;memoized variant
   (memoize hackage->guix-package))
diff --git a/tests/hackage.scm b/tests/hackage.scm
index 38a5825af7..fe4e0efb69 100644
--- a/tests/hackage.scm
+++ b/tests/hackage.scm
@@ -274,6 +274,52 @@ executable cabal
 (test-assert "hackage->guix-package test multiline desc (braced)"
   (eval-test-with-cabal test-cabal-multiline-braced match-ghc-foo))
 
+;; test hackage cabal revisions
+(define test-cabal-revision
+  "name: foo
+version: 1.0.0
+x-revision: 2
+homepage: http://test.org
+synopsis: synopsis
+description: description
+license: BSD3
+executable cabal
+  build-depends:
+    HTTP       >= 4000.2.5 && < 4000.3,
+    mtl        >= 2.0      && < 3
+")
+
+(define-package-matcher match-ghc-foo-revision
+  ('package
+    ('name "ghc-foo")
+    ('version "1.0.0")
+    ('source
+     ('origin
+       ('method 'url-fetch)
+       ('uri ('string-append
+              "https://hackage.haskell.org/package/foo/foo-";
+              'version
+              ".tar.gz"))
+       ('sha256
+        ('base32
+         (? string? hash)))))
+    ('build-system 'haskell-build-system)
+    ('inputs
+     ('quasiquote
+      (("ghc-http" ('unquote 'ghc-http)))))
+    ('arguments
+     ('quasiquote
+      ('#:cabal-revision
+       ("2" "0xxd88fb659f0krljidbvvmkh9ppjnx83j0nqzx8whcg4n5qbyng"))))
+    ('home-page "http://test.org";)
+    ('synopsis (? string?))
+    ('description (? string?))
+    ('license 'bsd-3)))
+
+(test-assert "hackage->guix-package test cabal revision"
+  (eval-test-with-cabal test-cabal-revision match-ghc-foo-revision))
+
+
 (test-assert "read-cabal test 1"
   (match (call-with-input-string test-read-cabal-1 read-cabal)
     ((("name" ("test-me"))
-- 
2.20.1 (Apple Git-117)