Note: we are releasing a bit earlier than planned due to #3624. As such, not all the binaries have been built yet, but the commonly used 64-bit binaries of Linux static, macOS, and Windows are available.
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Changes since v1.5.1
Complete overhaul of how snapshots are defined, the packages and extra-deps fields, and a number of related items. For full details, please see the writeup on these changes. PR #3249, see the PR description for a number of related issues.
Upgraded to version 2.0 of the Cabal library.
The --install-ghc flag is now on by default. For example, if you run stack build in a directory requiring a GHC that you do not currently have, Stack will automatically download and install that GHC. You can explicitly set install-ghc: false or pass the flag --no-install-ghc to regain the previous behavior.
stack ghci no longer loads modules grouped by package. This is always an improvement for plain ghci - it makes loading faster and less noisy. For intero, this has the side-effect that it will no longer load multiple packages that depend on TH loading relative paths. TH relative paths will still work when loading a single package into intero. See #3309
Setting GHC options for a package via ghc-options: in your stack.yaml will promote it to a local package, providing for more consistency with flags and better reproducibility. See: #849
The package-indices setting with Hackage no longer works with the 00-index.tar.gz tarball, but must use the 01-index.tar.gz file to allow revised packages to be found.
Options passsed via --ghci-options are now passed to the end of the invocation of ghci, instead of the middle. This allows using +RTS without an accompanying -RTS.
When auto-detecting --ghc-build, tinfo6 is now preferred over standard if both versions of libtinfo are installed
Addition of stack build --copy-compiler-tool, to allow tools like intero to be installed globally for a particular compiler. #2643
Stack will ask before saving hackage credentials to file. This new prompt can be avoided by using the save-hackage-creds setting. Please see #2159.
The GHCRTS environment variable will no longer be passed through to every program stack runs. Instead, it will only be passed through commands like exec, runghc, script, ghci, etc. See #3444.
ghc-options: for specific packages will now come after the options specified for all packages / particular sets of packages. See #3573.
The pvp-bounds feature is no longer fully functional, due to some issues with the Cabal library's printer. See #3550.
The with-hpack configuration option specifies an Hpack executable to use instead of the Hpack bundled with Stack. Please see #3179.
It's now possible to skip tests and benchmarks using --skip flag
GitSHA1 is now StaticSHA256 and is implemented using the StaticSize 64 ByteString for improved performance. See #3006
Dependencies via HTTP(S) archives have been generalized to allow local file path archives, as well as to support setting a cryptographic hash (SHA256) of the contents for better reproducibility.
Allow specifying --git-branch when upgrading
When running stack upgrade from a file which is different from the default executable path (e.g., on POSIX systems, ~/.local/bin/stack), it will now additionally copy the new executable over the currently running stack executable. If permission is denied (such as in /usr/local/bin/stack), the user will be prompted to try again using sudo. This is intended to assist with the user experience when the PATH environment variable has not been properly configured, see #3232.
stack setup for ghcjs will now install alex and happy if they are not present. See #3109.
Added stack ghci --only-main flag, to skip loading / importing all but main modules. See the ghci documentation page for further info.
Allow GHC's colored output to show through. GHC colors output starting with version 8.2.1, for older GHC this does nothing. Sometimes GHC's heuristics would work fine even before this change, for example in stack ghci, but this override's GHC's heuristics when they're broken by our collecting and processing GHC's output.
Extended the ghc-options field to support $locals, $targets, and $everything. See: #3329
Better error message for case that stack ghci file targets are combined with invalid package targets. See: #3342
For profiling now uses -fprof-auto -fprof-cafs instead of the deprecated -auto-all -caf-all. See: #3360
Better descriptions are now available for stack upgrade --help. See: #3070
When using Nix, nix-shell now depends always on gcc to prevent build errors when using the FFI. As ghc depends on gcc anyway, this doesn't increase the dependency footprint.
--cwd DIR can now be passed to stack exec in order to execute the program in a different directory. See: #3264
Plan construction will detect if you add an executable-only package as a library dependency, resulting in much clearer error messages. See: #2195.
Addition of --ghc-options to stack script to pass options directly to GHC. See: #3454
Log when each individual test suite finishes. See: #3552.
Avoid spurious rebuilds when using --file-watch by not watching files for executable, test and benchmark components that aren't a target. See: #3483.
Stack will now try to detect the width of the running terminal (only on POSIX for the moment) and use that to better display output messages. Work is ongoing, so some messages will not be optimal yet. The terminal width can be overriden with the new --terminal-width command-line option (this works even on non-POSIX).
Passing non local packages as targets to stack ghci will now cause them to be used as -package args along with package hiding.
Detect when user changed .cabal file instead of package.yaml. This was implemented upstream in hpack. See #3383.
Automatically run autoreconf -i as necessary when a configure script is missing. See #3534
GHC bindists can now be identified by their SHA256 checksum in addition to their SHA1 checksum, allowing for more security in download.
For filesystem setup-info paths, it's no longer assumed that the directory is writable, instead a temp dir is used. See #3188.
stack build --only-dependencies no longer builds local project packages that are depended on. See #3476.
Properly handle relative paths stored in the precompiled cache files. See #3431.
In some cases, Cabal does not realize that it needs to reconfigure, and must be told to do so automatically. This would manifest as a "shadowed dependency" error message. We now force a reconfigure whenever a dependency is built, even if the package ID remained the same. See #2781.
When --pvp-bounds is enabled for sdist or upload, internal dependencies could cause errors when uploaded to hackage. This is fixed, see #3290
Fixes a bug where nonexistent hackage versions would cause stack to suggest the same package name, without giving version info. See #3562
Fixes a bug that has existed since 1.5.0, where stack setup --upgrade-cabal would say that Cabal is already the latest version, when it wasn't.
Ensure that an extra-dep from a local directory is not treated as a $locals for GHC options purposes. See #3574.
Building all executables only happens once instead of every time. See #3229 for more info.