v1.19.0-rc.0

1. Enhancements

Elixir

• [Access] Add Access.values/0 for traversing maps and keyword lists values
• [Base] Add functions to verify if an encoding is valid, such as valid16?, valid64?, and so forth
• [Calendar] Support 2-arity options for Calendar.strftime/3 which receives the whole data type
• [Code] Add :migrate_call_parens_on_pipe formatter option
• [Code] Add :indentation option to Code.string_to_quoted/2
• [Code.Fragment] Preserve more block content around cursor in container_cursor_to_quoted
• [Code.Fragment] Add :block_keyword_or_binary_operator to Code.Fragment for more precise suggestions after operators and closing terminators
• [Code.Fragment] Add Code.Fragment.lines/1
• [Enum] Provide more information on Enum.OutOfBoundsError
• [Inspect] Allow optional: :all when deriving Inspect
• [Inspect.Algebra] Add optimistic/pessimistic groups as a simplified implementation of next_break_fits
• [IO.ANSI] Add ANSI codes to turn off conceal and crossed_out
• [Kernel] Allow controlling which applications are used during inference
• [Kernel] Support min/2 and max/2 as guards
• [Kernel.ParallelCompiler] Add each_long_verification_threshold which invokes a callback when type checking a module takes too long
• [Kernel.ParallelCompiler] Include lines in == Compilation error in file ... == slogans
• [Macro] Print debugging results from Macro.dbg/3 as they happen, instead of once at the end
• [Module] Do not automatically load modules after their compilation, guaranteeing a more consistent compile time experience and drastically improving compilation times
• [Protocol] Type checking of protocols dispatch and implementations
• [Regex] Add Regex.to_embed/2 which returns an embeddable representation of regex in another regex
• [String] Add String.count/2 to count occurrences of a pattern

ExUnit

• [ExUnit.CaptureLog] Parallelize log dispatch when multiple processes are capturing log
• [ExUnit.Case] Add :test_group to the test context
• [ExUnit.Doctest] Support ellipsis in doctest exceptions to match the remaining of the exception
• [ExUnit.Doctest] Add :inspect_opts option for doctest

IEx

• [IEx] Support multi-line prompts (due to this feature, :continuation_prompt and :alive_continuation_prompt are no longer supported as IEx configuration)
• [IEx.Autocomplete] Functions annotated with @doc group: "Name" metadata will appear within their own groups in autocompletion

Mix

• [mix] Add support for MIX_PROFILE_FLAGS to configure MIX_PROFILE
• [mix compile] Debug the compiler and type checker PID when MIX_DEBUG=1 and compilation/verification thresholds are met
• [mix compile] Add Mix.Tasks.Compiler.reenable/1
• [mix deps.compile] Support MIX_OS_DEPS_COMPILE_PARTITION_COUNT for compiling deps concurrently across multiple operating system processes
• [mix help] Add mix help Mod, mix help :mod, mix help Mod.fun and mix help Mod.fun/arity
• [mix test] Allow to distinguish the exit status between warnings as errors and test failures
• [mix xref graph] Add support for --format json
• [mix xref graph] Emit a warning if --source is part of a cycle
• [M ix.Task.Compiler] Add Mix.Task.Compiler.run/2

2. Bug fixes

Elixir

• [DateTime] Do not truncate microseconds regardless of precision in DateTime.diff/3
• [File] Properly handle permissions errors cascading from parent in File.mkdir_p/1
• [Kernel] not_a_map.key now raises BadMapError for consistency with other map operations
• [Regex] Fix Regex.split/2 returning too many results when the chunk being split on was empty (which can happen when using features such as /K)
• [Stream] Ensure Stream.transform/5 respects suspend command when its inner stream halts
• [URI] Several fixes to URI.merge/2 related to trailing slashes, trailing dots, and hostless base URIs

Mix

• [mix cmd] Preserve argument quoting in subcommands
• [mix format] Ensure the formatter does not go over the specified limit in certain corner cases
• [mix release] Fix RELEASE_SYS_CONFIG for Windows 11
• [mix test] Preserve files with no longer filter on mix test
• [mix xref graph] Provide more consistent output by considering strong connected components only when computing graphs

3. Soft deprecations (no warnings emitted)

Elixir

• [Inspect.Algebra] next_break_fits is deprecated in favor of optimistic/pessimistic groups
• [Node] Node.start/2-3 is deprecated in favor of Node.start/2 with a keyword list

Mix

• [mix compile] --no-protocol-consolidation is deprecated in favor of --no-consolidate-protocols for consistency with mix.exs configuration
• [mix compile.protocols] Protocol consolidation is now part of compile.elixir and has no effect

4. Hard deprecations

Elixir

• [Code] The on_undefined_variable: :warn is deprecated. Relying on undefined variables becoming function calls will not be supported in the future
• [File] Passing a callback as third argument to File.cp/3 is deprecated, pass it as a on_conflict: callback option instead
• [File] Passing a callback as third argument to File.cp_r/3 is deprecated, pass it as a on_conflict: callback option instead
• [Kernel] The struct update syntax, such as %URI{uri | path: "/foo/bar"} is deprecated in favor of pattern matching on the struct when the variable is defined and then using the map update syntax %{uri | path: "/foo/bar"}. Thanks to the type system, pattern matching on structs can find more errors, more reliably
• [Kernel.ParallelCompiler] Passing return_diagnostics: true as an option is required on compile, compile_to_path and require

Logger

• [Logger] The :backends configuration is deprecated, either set the :default_handler to false or start backends in your application start callback

Mix

• [mix] The :default_task, :preferred_cli_env, and :preferred_cli_target configuration inside def project in your mix.exs has been deprecated in favor of :default_task, :preferred_envs and :preferred_targets inside the def cli function
• [mix do] Using commas as task separator in mix do (such as mix do foo, bar) is deprecated, use + instead (as in mix do foo + bar)