Have Cabal build a Setup executable and test with it. #3260
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I recently discovered that build-tools can be used to specify dependencies on internal executables (haskell#220). This means that we can make a nice improvement to the package-tests test suite: instead of manually building a Setup.hs script ourselves, we can add one to the Cabal file for Cabal, and have the test suite have a build-tools dependency on it. Perhaps the only objection to this is that the Cabal *library* now has an executable cabal-setup. Maybe with some buildable shenanigans we can make it so that we never build this executable unless the user asks for it, or the test suite is enabled. Alternately, cabal-setup is a generally handy executable to have around. Signed-off-by: Edward Z. Yang <[email protected]>
| @@ -342,6 +342,14 @@ library | |||
| if !impl(ghc >= 7.0) | |||
| default-extensions: CPP | |||
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| executable cabal-setup | |||
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This means that cabal install Cabal will now also install cabal-setup. Would be nice to avoid that, perhaps by building cabal-setup only when a flag is enabled.
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Still testing, but how does something like this look:
diff --git a/Cabal/Cabal.cabal b/Cabal/Cabal.cabal
index 494eb97..b182bc6 100644
--- a/Cabal/Cabal.cabal
+++ b/Cabal/Cabal.cabal
@@ -212,6 +212,9 @@ source-repository head
flag bundled-binary-generic
default: False
+flag cabal-setup-buildable
+ default: False
+
library
build-depends:
array >= 0.1 && < 0.6,
@@ -347,6 +350,10 @@ library
default-extensions: CPP
executable cabal-setup
+ if flag(cabal-setup-buildable)
+ buildable: True
+ else
+ buildable: False
build-depends: base, Cabal
main-is: Setup.hs
-- Actually, we don't really want anything from tests; just
@@ -392,7 +399,11 @@ test-suite package-tests
PackageTests.TestSuiteTests.ExeV10.Check
PackageTests.PackageTester
hs-source-dirs: tests
- build-tools: cabal-setup
+ if flag(cabal-setup-buildable)
+ buildable: True
+ build-tools: cabal-setup
+ else
+ buildable: False
build-depends:
base,
containers,
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Yep, that's what I had I mind. Is Cabal smart enough to see that --enable-tests must imply cabal-setup-buildable: True? Then maybe the second conditional could be elided.
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It's not, because build-tools are not considered during dependency resolution; this is bug #220
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Ugh, this interacts poorly with new-build, now it thinks that the package has no component named package-tests. Reported in #3262.
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OK, well, this patch doesn't simplify that much, so I guess if the added executable is a deal breaker lets not put it in. |
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Canned. |
I recently discovered that build-tools can be used to specify
dependencies on internal executables (#220). This means that
we can make a nice improvement to the package-tests test suite:
instead of manually building a Setup.hs script ourselves,
we can add one to the Cabal file for Cabal, and have the
test suite have a build-tools dependency on it.
Perhaps the only objection to this is that the Cabal library
now has an executable cabal-setup. Maybe with some buildable
shenanigans we can make it so that we never build this executable
unless the user asks for it, or the test suite is enabled.
Alternately, cabal-setup is a generally handy executable to have
around.
Signed-off-by: Edward Z. Yang [email protected]