packages: 'supported-package?' binds '%current-system' for graph traversal.

Previously, (supported-package? coreutils "armhf-linux")
with (%current-system) = "x86_64-linux" would return false.  That's
because 'supported-package?' would traverse the x86_64 dependency graph,
which contains 'tcc-boot0', which supports x86 only.

Consequently, 'supported-package?' would match only 53 packages for
"armhf-linux" when running on x86, as is the case during continuous
integration.

* guix/packages.scm (package-transitive-supported-systems): Add an
optional 'system' parameter.  Use 'mlambda' instead of 'mlambdaq' for
memoization.
(supported-package?): Pass 'system' to 'package-transitive-supported-systems'.
* tests/packages.scm ("package-transitive-supported-systems, implicit inputs")
("package-transitive-supported-systems: reduced binary seed, implicit inputs"):
Remove calls to 'invalidate-memoization!', which no longer work and were
presumably introduced to work around the bug we're fixing (see commit
0db65c168fd6dec57a357735fe130c80feba5460).
* tests/packages.scm ("supported-package?"): Rewrite test to use only
existing system name since otherwise 'bootstrap-executable' raises an
exception.
("supported-package? vs. system-dependent graph"): New test.

1 files changed, 29 insertions, 7 deletions

diff --git a/tests/packages.scm b/tests/packages.scm
index 0478fff237..423c5061aa 100644
--- a/tests/packages.scm
+++ b/tests/packages.scm
@@ -341,7 +341,6 @@
                (build-system gnu-build-system)
                (supported-systems
                 `("does-not-exist" "foobar" ,@%supported-systems)))))
-    (invalidate-memoization! package-transitive-supported-systems)
     (parameterize ((%current-system "armhf-linux")) ; a traditionally-bootstrapped architecture
       (package-transitive-supported-systems p))))
 
@@ -354,17 +353,40 @@
              (build-system gnu-build-system)
              (supported-systems
               `("does-not-exist" "foobar" ,@%supported-systems)))))
-    (invalidate-memoization! package-transitive-supported-systems)
     (parameterize ((%current-system "x86_64-linux"))
       (package-transitive-supported-systems p))))
 
 (test-assert "supported-package?"
-  (let ((p (dummy-package "foo"
-             (build-system gnu-build-system)
-             (supported-systems '("x86_64-linux" "does-not-exist")))))
+  (let* ((d (dummy-package "dep"
+              (build-system trivial-build-system)
+              (supported-systems '("x86_64-linux"))))
+         (p (dummy-package "foo"
+              (build-system gnu-build-system)
+              (inputs `(("d" ,d)))
+              (supported-systems '("x86_64-linux" "armhf-linux")))))
+    (and (supported-package? p "x86_64-linux")
+         (not (supported-package? p "i686-linux"))
+         (not (supported-package? p "armhf-linux")))))
+
+(test-assert "supported-package? vs. system-dependent graph"
+  ;; The inputs of a package can depend on (%current-system).  Thus,
+  ;; 'supported-package?' must make sure that it binds (%current-system)
+  ;; appropriately before traversing the dependency graph.  In the example
+  ;; below, 'supported-package?' must thus return true for both systems.
+  (let* ((p0a (dummy-package "foo-arm"
+                (build-system trivial-build-system)
+                (supported-systems '("armhf-linux"))))
+         (p0b (dummy-package "foo-x86_64"
+                (build-system trivial-build-system)
+                (supported-systems '("x86_64-linux"))))
+         (p   (dummy-package "bar"
+                (build-system trivial-build-system)
+                (inputs
+                 (if (string=? (%current-system) "armhf-linux")
+                     `(("foo" ,p0a))
+                     `(("foo" ,p0b)))))))
     (and (supported-package? p "x86_64-linux")
-         (not (supported-package? p "does-not-exist"))
-         (not (supported-package? p "i686-linux")))))
+         (supported-package? p "armhf-linux"))))
 
 (test-skip (if (not %store) 8 0))