#10152: Testsuite diffs can be misleading when normalisers are in use -------------------------------------+------------------------------------- Reporter: ezyang | Owner: Type: task | Status: new Priority: low | Milestone: Component: Test Suite | Version: 7.11 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: None/Unknown | Unknown/Multiple Blocked By: | Test Case: Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by Thomas Miedema <thomasmiedema@…>): In [changeset:"5ddd90415f307cac72d75d86da58e552b168ee30/ghc"]: {{{ #!CommitTicketReference repository="ghc" revision="5ddd90415f307cac72d75d86da58e552b168ee30" Testsuite: diff non-whitespace normalised output (#10152) On a test failure, we show a diff between the expected and the actual output. The method of how we do this has changed a couple of times: * In 2007: 9951189ccf90b709436fa55ee49eeef031f79f4e "On failure, diff the normalised test outputs" * In 2011: 3019b1e409c129ef7af63e6a7408fb36ec44444b "When the output files differ, present the diffs between the *actual* output, not the normalised output. The latter may have newlines removed, making the diff unreadable." * In 2015 (now): do something in between. - Do apply the normalisers again, to make the diff smaller (only showing the actual problem). - But don't apply normalise_whitespace, as it indeed makes the diff unreadable. Differential Revision: https://phabricator.haskell.org/D984 }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10152#comment:1> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler