Haskell-stack is giving “Download expectation failure”

Question

I'm trying to use stack to build a project, and I'm receiving 'Download expectation failure' when running 'stack build'.

C:\Users\T60\Dropbox\notebooks-stack>stack build
Setting codepage to UTF-8 (65001) to ensure correct output from GHC
Download expectation failure: content hash (SHA512)
Expected: aa1178f08ad3364c504ee790dac9b0774b7461fa7ea0a8f2c3ad82943d109602debcf4
a8a83090815fef487ceac40019f8b5594ab0043f36e019d69bc5f76853 (ByteString)
Actual:   91f514e1731ef3c2063ff5ab6156242755b2b2b462d4a1f40f150d96cf714f7b7b5b19
c7705e5129bbb9876216ca86ff52e49cd7604d83e4b4150172c9bda228
For: https://s3.amazonaws.com:443/hackage.fpcomplete.com/package/SHA-1.6.4.2.tar
.gz
Pr

The relevant portion of my cabal file is:

  build-depends:       base >= 4.7 && < 5
                       , bytestring
                       , sqlite-simple
                       , time
                       , SHA

I've traced the error message to the show instance of VerifiedDownloadException in Verified.hs in the stack source code, but for what this actually means (something dumb in my cabal file, bad package on stackage, internal error in stack...) I have no idea.

I'm running Windows 7 32-bit.

Answer 1

It turns out that this was a bug in stack, where a corrupted download would fail to be properly redownloaded. It's been fixed in the latest builds.