2.4.0~alpha2

This is the second alpha release of opam 2.4.0.

Binaries and full archive are signed by the opam dev team (fingerprint 92C5 26AE 50DF 3947 0EB2 911B ED4C F1CA 67CB AA92).

Please see our blog post for a highlight on the major changes and upgrade instructions.

Changelog:

Changes

• Do not include compiler packages flagged with avoid-version/deprecated in the generated invariant when calling opam switch create [name] <version> [#6494 @kit-ty-kate]
• Cygwin: Fallback to the existing setup-x86_64.exe if its upgrade failed to be fetched [#6482 @kit-ty-kate - fix #6495, partial fix #6474]
• Fix a memory leak happening when running large numbers of commands or opening large number of opam files [#6485 @hannesm - fix #6484]
• Remove handling of the OPAMSTATS environment variable [#6485 @hannesm]

Regression fixes from 2.4.0~alpha1

• Fix a crash when updating a repository that is deleting or adding empty files [#6490 @kit-ty-kate]
• Fix an extreme performance issue (takes several hours) when applying a large repository update [#6490 @kit-ty-kate]
• Fix a crash when updating a git repository that moved a file to a new directory [#6490 @kit-ty-kate]

Build changes

• Update the requirement for the patch library to 3.0.0~alpha2 [#6490 @kit-ty-kate]
• Upgrade the downloaded-if-missing patch library to 3.0.0~alpha2 [#6490 @kit-ty-kate]

Testing and documentation

• Improve and extend the testsuite [#6490 #6494 @rjbou @kit-ty-kate]
• Improve and extend the test infrastructure [#6277 @rjbou @kit-ty-kate]

API updates

opam-core

• OpamArg.environment_variable: make STATS as removed from cli 2.3 [#6485 @rjbou]
• OpamClientConfig: remove STATS variant and related print_stats field in config record [#6485 @hannesm]

opam-format

• OpamFile: remove Stats module [#6485 @hannesm]

opam-core

• OpamSystem: remove print_stats function [#6485 @hannesm]
• OpamSystem: add the rmdir_cleanup function [#6490 @kit-ty-kate]
• OpamSystem.dir_is_empty: Speedup and change its type to handle unreachable directories better [#6490 @kit-ty-kate]
• OpamSystem.internal_patch: remove parent directories when all of their content has been moved somewhere else [#6490 @kit-ty-kate]
• OpamSystem.internal_patch: fix moving files to new directories when receiving a git diff [#6490 @kit-ty-kate]