Warning: The install command is a part of the legacy v1 style of cabal usage.

Please switch to using either the new project style and the new-install
command or the legacy v1-install alias as new-style projects will become the
default in the next version of cabal-install. Please file a bug if you cannot
replicate a working v1- use case with the new-style commands.

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Resolving dependencies...
Starting     parser-combinators-tests-1.2.1
Building     parser-combinators-tests-1.2.1
Failed to install parser-combinators-tests-1.2.1
Build log ( /home/builder/.cabal/logs/ghc-8.6.3/parser-combinators-tests-1.2.1-8xDyxH1B3v4FX6uqzuFCc5.log ):
cabal: Entering directory '/tmp/cabal-tmp-27883/parser-combinators-tests-1.2.1'
Configuring parser-combinators-tests-1.2.1...
Building parser-combinators-tests-1.2.1...
Warning: No documentation was generated as this package does not contain a
library. Perhaps you want to use the --executables, --tests, --benchmarks or
--foreign-libraries flags.
cabal: No executables and no library found. Nothing to do.

cabal: Leaving directory '/tmp/cabal-tmp-27883/parser-combinators-tests-1.2.1'
cabal: Error: some packages failed to install:
parser-combinators-tests-1.2.1-8xDyxH1B3v4FX6uqzuFCc5 failed during the final
install step. The exception was:
ExitFailure 1