OCaml Changelog

Fixes

• Fix shutting down an already closed socket (#740)

Fixes

• Fix preprocessing, ppx, and reason support (#735 fixes #696, #706)

• Support include in folding ranges (#730)

Features

• Fix cancellation mechanism for all requests (#707)

• Allow cancellation of formatting requests (#707)

• Add --fallback-read-dot-merlin to the LSP Server (#705). If ocamllsp is started with this new flag, it will fall back to looking for Merlin configuration in .merlin files rather than calling dune ocaml-merlin. (#705)

• Support folding more ranges (#692)

• Improve parsing of ocamlc errors. We now correctly strip excerpts and parse alerts (#5879, @rgrinberg)

• The (libraries) field of the coq.theory stanza has been renamed to (plugins) and the Coq language version has been bumped to 0.5.

• Add support for OCaml 5.0 (#377 @dra27)

• Update expansion context to leave out value name when multiple are defined at once. (#351, @ceastlund)
• Add support for OCaml 5.0 (#348, @pitag-ha)
• Add Code_path.enclosing_value (#349, @ceastlund)
• Add Code_path.enclosing_module (#346, @ceastlund)
• Expand code generated by ~enclose_intf and ~enclose_impl (#345, @ceastlund)
• Add type annotations to code generated by metaquot (#344, @ceastlund)
• Fix typo in description field of dune-project (#343, @ceastlund)
• Fix Ast_pattern.many (#333, @nojb)
• Fix quoter and optimize identifier quoting (#327, @sim642)
• Driver, when run with --check: Allow toplevel_printer attributes (#340, @pitag-ha)
• Documentation: Add a section on reporting errors by embedding extension nodes in the AST (#318, @panglesd)
• Driver: In the case of ppxlib internal errors, embed those errors instead of raising to return a meaningful AST (#329, @panglesd)
• API: For each function that could raise a located error, add a function that return a result instead (#329, @panglesd)

• Add support for 5.0 (#122, @pitag-ha)

• Sandbox preprocessing, lint, and dialect rules by default. All these rules now require precise dependency specifications (#5807, @rgrinberg)

• Allow list expansion in the pps specification for preprocessing (#5820, @Firobe)

• Add warnings 67-69 to dune's default set of warnings. These are warnings of the form "unused X.." (#5844, @rgrinberg)

• Introduce project "composition" for coq theories. Coq theories in separate projects can now refer to each other when in the same workspace (#5784, @Alizter, @rgrinberg)

• Fix hint message for data_only_dirs that wrongly mentions the unknown constructor data_only (#5803, @lambdaxdotx)

• Fix creating sandbox directory trees by getting rid of buggy memoization (#5794, @rgrinberg, @snowleopard)

• Handle directory dependencies in sandboxed rules. Previously, the parents of these directory dependencies weren't created. (#5754, @rgrinberg)

• Set the exit code to 130 when dune is terminated with a signal (#5769, fixes #5757)

• Support new locations of unix, str, dynlink in OCaml >= 5.0 (#5582, @dra27)

• The coq.theory stanza now produces rules for running coqdoc. Given a theory named mytheory, the directory targets mytheory.html/ and mytheory.tex/ or additionally the aliases @doc and @doc-latex will build the HTML and LaTeX documentation repsectively. (#5695, fixes #3760, @Alizter)

• Coq theories marked as (boot) cannot depend on other theories (#5867, @ejgallego)

• Ignore bigarray in (libraries) with OCaml >= 5.0. (#5526, fixes #5494, @moyodiallo)

• Start with :standard when building the ctypes generated foreign stubs so that we include important compiler flags, such as -fPIC (#5816, fixes #5809).

• Bump ppxlib's AST to 4.14/5.00 (#320, @pitag-ha)

Removed

• Profiles compact and sparse are now removed (#2075, @gpetiot)
• Options align-cases, align-constructors-decl and align-variants-decl are now removed (#2076, @gpetiot)
• Option disable-outside-detected-project is now removed (#2077, @gpetiot)

Deprecated

• Cancel the deprecations of options that are not set by the preset profiles (#2074, @gpetiot)

Bug fixes

• emacs: Remove temp files in the event of an error (#2003, @gpetiot)
• Fix unstable comment formatting around prefix op (#2046, @gpetiot)

Changes

• Qtest comments are not re-formatted (#2034, @gpetiot)
• ocamlformat-rpc is now distributed through the ocamlformat package (#2035, @Julow)
• Doc-comments code blocks with a language other than 'ocaml' (set in metadata) are not parsed as OCaml (#2037, @gpetiot)
• More comprehensible error message in case of version mismatch (#2042, @gpetiot)
• The global configuration file ($XDG_CONFIG_HOME or $HOME/.config) is only applied when no project is detected, --enable-outside-detected-project is set, and no applicable .ocamlformat file has been found. Global and local configurations are no longer used at the same time. (#2039, @gpetiot)
• Set ocaml-version to a fixed version (4.04.0) by default to avoid reproducibility issues and surprising behaviours (#2064, @kit-ty-kate)
• Split option --numeric=X-Y into --range=X-Y and --numeric (flag). For now --range can only be used with --numeric. (#2073, #2082, @gpetiot)

New features

• New syntax (*= ... *) for verbatim comments (#2028, @gpetiot)
• Preserve the begin-end construction in the AST (#1785, @hhugo, @gpetiot)
• Preserve position of comments located after the semi-colon of the last element of lists/arrays/records (#2032, @gpetiot)
• Option --print-config displays a warning when an .ocamlformat file defines redundant options (already defined by a profile) (#2084, @gpetiot)

Fixed

• Fix project name detection from dune-project. The parser could get confused when opam file generation is used. Now it only considers the first (name X) in the file. (#445, #446, @emillon)

Fixes

• Stop leaking file descriptors like a sieve (#701)

• Fixed dune describe workspace --with-deps so that it correctly handles Reason files, as well as files any other dialect. (#5701, @esope)

• Disable alerts when compiling code in vendored directories (#5683, @NathanReb)

• Fixed dune describe --with-deps, that crashed when some preprocessing was required in a dune file using per_module. (#5682, fixes #5680, @esope)

• Add $ dune describe pp to print the preprocssed ast of sources. (#5615, fixes #4470, @cannorin)

• Report dune file evaluation errors concurrently. In the same way we report build errors. (#5655, @rgrinberg)

• Watch mode now default to clearing the terminal on rebuild (#5636, fixes, #5216, @rgrinberg)

• The output of jobs that finished but were cancelled is now omitted. (#5631, fixes #5482, @rgrinberg)

• Allows to configure all the default destination directories with ./configure (adds bin, sbin, data, libexec). Use OPAM_SWITCH_PREFIX instead of calling the opam binaries in dune install. Fix handling of multiple libdir in ./configure for handling /usr/lib/ocaml/ and /usr/local/lib/ocaml. In dune install forbid relative directories in libdir, docdir and others specific directory setting because their handling was inconsistent (#5516, fixes #3978 and #5455, @bobot)

• --terminal-persistence=clear-on-rebuild will no longer destroy scrollback on some terminals (#5646, @rgrinberg)

• Add a fmt command as a shortcut of dune build @fmt --auto-promote (#5574, @tmattio)

• Watch mode now tracks copied external files, external directories for dependencies, dune files in OCaml syntax, files used by include stanzas, dune-project, opam files, libraries builtin with compiler, and foreign sources (#5627, #5645, #5652, #5656, #5672, #5691, #5722, fixes #5331, @rgrinberg)

• Improve metrics for cram tests. Include test names in the event and add a category for cram tests (#5626, @rgrinberg)

• Allow specifying multiple licenses in project file (#5579, fixes #5574, @liyishuai)

• Match glob_files only against files in external directories (#5614, fixes #5540, @rgrinberg)

• Add pid's to chrome trace output (#5617, @rgrinberg)

• Fix race when creating local cache directory (#5613, fixes #5461, @rgrinberg)

• Add not to boolean expressions (#5610, fix #5503, @rgrinberg)

• Fix relative dependencies outside the workspace (#4035, fixes #5572, @bobot)

• Allow to specify --prefix via the environment variable DUNE_INSTALL_PREFIX (#5589, @vapourismo)

• Dune-site.plugin: add support for archive(native|byte, plugin) used in the wild before findlib documented plugin(native|byte) in 2015 (#5518, @bobot)

• Fix a bug where Dune would not correctly interpret META files in alternative layout (ie when the META file is named META.$pkg). The Llvm bindings were affected by this issue. (#5619, fixes #5616, @nojb)

• Support (binaries) in (env) in dune-workspace files (#5560, fix #5555, @emillon)

• (mdx) stanza: add support for (locks). (#5628, fixes #5489, @emillon)

• (mdx) stanza: support including files in different directories using relative paths, and provide better error messages when paths are invalid (#5703, #5704, fixes #5596, @emillon)

• Fix ctypes rules for external lib names which aren't valid ocaml names (#5667, fixes #5511, @Khady)

• Fix process termination. Once the lsp server is stepped, the process will gracefully terminate (#697, fixes #694)

• Forward stderr from dune's merlin configuration to the lsp server's stderr (#697)

• Fix bug with large buffers being resized incorrectly in Lev

• Add folding ranges for more AST types (#680)

Fixes

• Enable dune rpc integration by default (#691, fixes #690)

Fixes

• Fix running external processes on Windows

• Fix build on Cygwin. (#5593, fixes 5577, @nojb)

• Fix execution of (system ..) actions on Windows. (#5593, fixes #5523, @nojb)

Fixes

• Fix Uri handling on Windows

• Fix build on MSVC 2015

• Add sourcehut as an option for defining project sources in dune-project files. For example, (source (sourcehut user/repo)). (#5564, @rgrinberg)

• Add dune coq top command for running a Coq toplevel (#5457, @rlepigre)

• Fix dune exec dumping database in wrong directory (#5544, @bobot)

• Always output absolute paths for locations in RPC reported diagnostics (#5539, @rgrinberg)

• Add (deps <deps>) in ctype field (#5346, @bobot)

• Add (include <file>) constructor to dependency specifications. This can be used to introduce dynamic dependencies (#5442, @anmonteiro)

• Ensure that dune describe computes a transitively closed set of libraries (#5395, @esope)

• Add direct dependencies to $ dune describe output (#5412, @esope)

• Show auto-detected concurrency on Windows too (#5502, @MisterDA)

• Fix operations that remove folders with absolute path. This happens when using esy (#5507, @EduardoRFS)

• Dune will not fail if some directories are non-empty when uninstalling. (#5543, fixes #5542, @nojb)

• coqdep now depends only on the filesystem layout of the .v files, and not on their contents (#5547, helps with #5100, @ejgallego)

• The mdx stanza 0.2 can now be used with (implicit_transitive_deps false) (#5558, fixes #5499, @emillon)

• Fix missing parenthesis in printing of corresponding terminal command for (with-outputs-to ) (#5551, fixes #5546, @Alizter)

Features

• Add support for dune in watch mode. The lsp server will now display build errors in the diagnostics and offer promotion code actions.

• Re-introduce ocamlformat-rpc (#599, fixes #495)

Fixes

• Fix workspace symbols that could have a wrong path in some cases (#675)

Fixes

• Compatiblity with OCaml 4.14.0

Fixes

• Patch merlin to remove the result module

• merlin binary
  • don't reset the environment when running merlin in single mode so that the parent environment is forwarded the the child processes (#1425)
  • filter dups in source paths (#1218)
  • improve load path performance (#1323)
  • fix handlink of ppx's under Windows (#1413)
  • locate: look for original source files before looking for preprocessed files (#1219 by @ddickstein, fixes #894)
  • handle = syntax in compiler flags (#1409)
  • expose all destruct exceptions in the api (#1437)
  • fix superfluous break in error reporting (#1432)
  • recognise binding operators in locate and occurrences (#1398, @mattiase)
  • remove dependency on Result (#1441, @kit-ty-kate)
  • use the new "shapes" generated by the compiler to perform precise jump-to-definition (#1431)
• editor modes
  • fix an issue in Neovim where the current line jumps to the top of the window on repeated calls to MerlinTypeOf (#1433 by @ddickstein, fixes #1221)
  • add module, module type, and class imenu items for emacs (#1244, @ivg)
  • add prefix argument to force or prevent opening in a new buffer in locate command (#1426, @panglesd)
  • add type-on-hover functionality for vim (#1439, @nilsbecker)
  • add a dedicated buffer *merlin-errors* containing the last viewed error (#1414, @panglesd)
• test suite
  • make merlin-wrapper create a default .merlin file only when there is no dune-project to let tests use dune ocaml-merlin reader. (#1425)
  • cover locate calls on module aliases with and without dune
  • Add a test expliciting the interaction between locate and Dune's generated source files (#1444)

• Add support for OCaml 5.0 (#371 @favonia)

• Add support for OCaml 5.0 (#355, @pitag-ha)

• Added error_extensionf function to the Location module (#316, @panglesd)
• Ast patterns: add drop and as patterns (#313 by @Kakadu, review by @pitag-ha)
• Fixed a bug resulting in disscarded rewriters in the presence of instrumentations, as well as a wrong order of rewriting (#296, @panglesd)
• Driver: Append the last valid AST to the error in case of located exception when embedding errors (#315, @panglesd)

• Do not enable warnings 63-70 by default (#5476, fixes #5464, @rgrinberg)

• Allow %{read-lines} to introduce dynamic dependencies like %{read}. (#5440, @anmonteiro)

• Look up gmake before make (#5474, fixes #5470, @rgrinberg)

• Handle empty output from getconf (#5473 fixes #5471, @mndrix)

• Depend on any provided foreign_archives for ctypes stub generation (#5475, @mbacarella)

Bug fixes

• Add missing parentheses around variant class arguments (#1967, @gpetiot)
• Fix indentation of module binding RHS (#1969, @gpetiot)
• Fix position of := when assignment-operator=end-line (#1985, @gpetiot)
• Fix position of comments attached to constructor decl (#1986, @gpetiot)
• Do not wrap docstrings, wrap-comments should only impact non-documentation comments, wrapping invalid docstrings would cause the whole file to not be formatted (#1988, @gpetiot)
• Do not break between 2 module items when the first one has a comment attached on the same line. Only a comment on the next line should induce a break to make it clear to which element it is attached to (#1989, @gpetiot)
• Preserve position of comments attached to the last node of a subtree (#1667, @gpetiot)
• Do not override the values of the following non-formatting options when a profile is set: comment-check, disable, max-iters, ocaml-version, and quiet (#1995, @gpetiot).
• Remove incorrect parentheses around polymorphic type constraint (#2002, @gpetiot)
• Handle cases where an attribute is added to a bind expression, e.g. (x >>= (fun () -> ())) [@a] (#2013, @emillon)
• Fix indentation of constraints of a package type pattern (#2025, @gpetiot)

Changes

• More expressions are considered "simple" (not inducing a break e.g. as an argument of an application):
  • Variants with no argument (#1968, @gpetiot)
  • Empty or singleton arrays/lists (#1943, @gpetiot)
• Print odoc code block delimiters on their own line (#1980, @gpetiot)
• Make formatting of cons-list patterns consistent with cons-list expressions, (::) operators are aligned when possible, comments position also improved (#1983, @gpetiot)
• Apply 'sequence-style' to add a space before ';;' between toplevel items, consistently with the formatting of ';' in sequences (#2004, @gpetiot)

New features

• Format toplevel phrases and their output (#1941, @Julow, @gpetiot). This feature is enabled with the flag --parse-toplevel-phrases. Toplevel phrases are supported when they are located in doc-comments blocks and cinaps comments. Whole input files can also be formatted as toplevel phrases with the flag --repl-file.

RPC

• ocamlformat-rpc-lib is now functorized over the IO (#1975, @gpetiot). Now handles Csexp.t types instead of Sexplib0.Sexp.t.
• RPC v2 (#1935, @panglesd): Define a 'Format' command parameterized with optionnal arguments to set or override the config and path, to format in the style of a file.
• Prevent RPC to crash on version mismatch with .ocamlformat (#2011, @panglesd, @Julow)

Fixed

• Fix compatibility with Cmdliner 1.1.0. This also unfortunately means that the minimum OCaml version is 4.08 now. (#429, @NathanReb)

Fixes

• Fix more debouncing bugs (#629)

Fixes

• Catch merlin desturct exceptions (#626)

• Fix broken debouncing (#627)

• Fix compilation on MacOS SDK < 10.13. The native watch mode is disabled in such instances (#5431 fix #5430, @rgrinberg)

• Do no add workspace_root to BUILD_PATH_PREFIX_MAP for projects before 3.0 (5448, @rgrinberg)

• Fix performance regression in incremental builds (#5439, @snowleopard)

• Fix digest computation bug introduced in 3.0.1 (#5451, @rgrinberg)

Fixes

• Fix executing ppx executables

Features

• Add better support for code folding: more folds and more precise folds

Fixes

• Fix infer interface code action crash when implementation source does not exist (#597)

• Improve error message when the reason plugin for merlin is absent (#608)

• Fix chdir races when running ppx (#550)

• More accurate completion kinds. New completion kinds for variants and fields. Removed inaccurate completion kinds for constructors and types. (#510)

• Fix handling request cancellation (#616)

• Remove uchar and seq dummy ocamlfind libraries from dune's builtin library database (#5260, @kit-ty-kate)

• Add a DUNE_DIFF_COMMAND environment variable to match --diff-command command-line parameter (@raphael-proust, fix #5369, #5375)

• Add support for odoc-link rules (#5045, @jonludlam, @lubegasimon)

• Dune will no longer generate documentation for hidden modules (#5045, @jonludlam, @lubegasimon)

• Parse the native_pack_linker field of ocamlc -config (#5281, @TheLortex)

• Fix plugins with dot in the name (#5182, @bobot, review @rgrinberg)

• Don't generate the dune-site build part when not needed (#4861, @bobot, review @kit-ty-kate)

• Fix installation of implementations of virtual libraries (#5150, fix #3636, @rgrinberg)

• Run tests in all modes defined. Previously, jsoo was excluded. (@hhugo, #5049, fix #4951)

• Allow to configure the alias to run the jsoo tests (@hhugo, #5049, #4999)

• Set jsoo compilation flags in the env stanza (@hhugo, #5049, #1613)

• Allow to configure jsoo separate compilation in the env stanza. Previously, it was hard coded to always be enabled in the dev profile. (@hhugo, #5049, fix #970)

• Fix build-info version in jsoo executables (@hhugo, #5049, fix #4444)

• Pass -no-check-prims when building bytecode for jsoo (@hhugo, #5049, #4027)

• Fix jsoo builds when dynamically linked foreign archives are disabled (@hhugo, #5049)

• Disallow empty packages starting from 3.0. Empty packages may be re-enabled by adding the (allow_empty) to the package stanza in the dune-project file. (#4867, fix #2882, @kit-ty-kate, @rgrinberg)

• Add link_flags field to the executable field of inline_tests (#5088, fix #1530, @jvillard)

• In watch mode, use fsevents instead of fswatch on OSX (#4937, #4990, fixes #4896 @rgrinberg)

• Remove inotifywait watch mode backend on Linux. We now use the inotify API exclusively (#4941, @rgrinberg)

• Report cycles between virtual libraries and their implementation (#5050, fixes #2896, @rgrinberg)

• Warn when lang versions have an ignored suffix. (lang dune 2.3.4) or (lang dune 2.3suffix) were silently parsed as 2.3 and we know suggest to remove the prefix. (#5040, @emillon)

• Allow users to specify dynamic dependencies in rules. For example (deps %{read:foo.gen}) (#4662, fixes #4089, @jeremiedimino)

• Sandbox infer rules for menhir. Fixes possible "inconsistent assumptions" errors (#5015, @rgrinberg)

• Experimental support for ctypes stubs (#3905, fixes #135, @mbacarella)

• Fix interpretation of binaries defined in the env stanza. Binaries defined in x/dune wouldn't be visible in `x/*/**/dune. (#4975, fixes #4976, @Leonidas-from-XIV, @rgrinberg)

• Do not list private libraries in package listings (#4945, fixes #4799, @rgrinberg)

• Allow spaces in cram test paths (#4980, fixes #4162, @rgrinberg)

• Improve error handling of misbehaving cram scripts. (#4981, fix #4230, @rgrinberg)

• Fix foreign_stubs inside a tests stanza. Previously, dune would crash when this field was present (#4942, fix #4946, @rgrinberg)

• Add the enabled_if field to inline_tests within the library stanza. This allows us to disable executing the inline tests while still allowing for compilation (#4939, @rgrinberg)

• Generate a dune-project when initializing projects with dune init proj ... (#4881, closes #4367, @shonfeder)

• Allow spaces in the directory argument of the subdir stanza (#4943, fixes #4907, @rgrinberg)

• Add a %{toolchain} expansion variable (#4899, fixes #3949, @rgrinberg)

• Include dependencies of executables when creating toplevels (either dune top or dune utop) (#4882, fixes #4872, @Gopiancode)

• Fixes opam META file requires entry for private libs (#4841, fixes #4839, @toots)

• Fixes dune exec not adding .exe on Windows (#4371, fixes #3322, @MisterDA)

• Allow multiple cinaps stanzas in the same directory (#4460, @rgrinberg)

• Fix $ dune subst in empty git repositories (#4441, fixes #3619, @rgrinberg)

• Improve interpretation of ansi escape sequence when spawning processes (#4408, fixes #2665, @rgrinberg)

• Allow (package pkg) in dependencies even if pkg is an installed package (#4170, @bobot)

• Allow %{version:pkg} to work for external packages (#4104, @kit-ty-kate)

• Add (glob_files_rec <dir>/<glob>) for globbing files recursively (#4176, @jeremiedimino)

• Automatically generate empty .mli files for executables and tests (#3768, fixes #3745, @CraigFe)

• Add ocaml command subgroup for OCaml related commands such as utop, top, and merlin (#3936, @rgrinberg).

• Detect unknown variables more eagerly (#4184, @jeremiedimino)

• Improve location of variables and macros in error messages (#4205, @jeremiedimino)

• Auto-detect dune-project files as dune files in Emacs (#4222, @shonfeder)

• Dune no longer automatically create or edit dune-project files (#4239, fixes #4108, @jeremiedimino)

• Warn if dune-project is not found (fatal in release mode) (#5343, @emillon)

• Cleanup temporary files after running $ dune exec. (#4260, fixes #4243, @rgrinberg)

• Add a new subcommand dune ocaml dump-dot-merlin that prints a mix of all the merlin configuration of a directory (defaulting to the current directory) in the Merlin configuration syntax. (#4250, @voodoos)

• Enable cram tests by default (#4262, @rgrinberg)

• Drop support for opam 1.x (#4280, @jeremiedimino)

• Stop calling ocamlfind to determine the library search path or library installation directory. This makes the behavior of Dune simpler and more reproducible (#4281, @jeremiedimino)

• Remove the external-lib-deps command. This command was only approximative and the cost of maintainance was getting too high. We removed it to make room for new more important features (#4298, @jeremiedimino)

• It is now possible to define action dependencies through a chain of aliases. (#4303, @aalekseyev)

• If an .ml file is not used by an executable, Dune no longer report parsing error in this file (#4330, @jeremiedimino)

• Add support for sandboxing using hard links (#4360, Andrey Mokhov)

• Fix dune crash when subdir is an absolute path (#4366, @anmonteiro)

• Changed the implementation of actions attached to aliases, as in (rule (alias runtest) (action (run ./test))). A visible result for users is that such actions are now memoized for longer. For instance:

  $ echo '(rule (alias runtest) (action (echo "X=%{env:X=0}\n")))` > dune
  $ X=1 dune runtest
  X=1
  $ X=2 dune runtest
  X=2
  $ X=1 dune runtest
  

  Previously, Dune would have re-executed the action again at the last line. Now it remembers the result of the first execution.

• Fix a bug where dune would always re-run all actions that produce symlinks, even if their dependencies did not change. (#4405, @aalekseyev)

• Fix a bug that was causing Dune to re-hash generated files more often than necessary (#4419, @jeremiedimino)

• Fields allowed in the config file are now also allowed in the workspace file (#4426, @jeremiedimino)

• Add options to control how Dune should handle stdout and stderr of actions when then succeed. It is now possible to ask Dune to ignore the stdout of actions when they succeed or to request that the stderr of actions must be empty. This allows to reduce the noise of large builds (#4422, #4515, @jeremiedimino)

• The @all alias no longer depends directly on copies of files from the source directory (#4461, @nojb)

• Allow dune-file as an alternative file name for dune files (needs to be enabled in the dune-project file) (#4428, @nojb)

• Drop support for upgrading jbuilder projects (#4473, @jeremiedimino)

• Extend the environment variable BUILD_PATH_PREFIX_MAP to rewrite the root of the build dir (or sandbox) to /workspace_root (#4466, @jeremiedimino)

• Simplify the implementation of build cache. We stop using the cache daemon to access the cache and instead write to and read from it directly. The new cache implementation is based on Jenga's cache library, which was thoroughly tested on large-scale builds. Using Jenga's cache library will also make it easier for us to port Jenga's cloud cache to Dune. (#4443, #4465, Andrey Mokhov)

• More informative error message when Dune can't read a target that's supposed to be produced by the action. Old message is still produced on ENOENT, but other errors deserve a more detailed report. (#4501, @aalekseyev)

• Fixed a bug where a sandboxed action would fail if it declares no dependencies in its initial working directory or any directory it chdirs into. (#4509, @aalekseyev)

• Fix a crash when clearing temporary directories (#4489, #4529, Andrey Mokhov)

• Dune now memoizes all errors when running in the file-watching mode. This speeds up incremental rebuilds but may be inconvenient in rare cases, e.g. if a build action fails due to a spurious error, such as running out of memory. Right now, the only way to force such actions to be rebuilt is to restart Dune, which clears all memoized errors. In future, we would like to provide a way to rerun all actions failed due to errors without restarting the build, e.g. via a Dune RPC call. (#4522, Andrey Mokhov)

• Remove dune compute. It was broken and unused (#4540, @jeremiedimino)

• No longer generate an approximate merlin files when computing the ocaml flags fails, for instance because they include the contents of a file that failed to build. This was a niche feature and it was getting in the way of making Dune's core better. (#4607, @jeremiedimino)

• Make Dune display the progress indicator in all output modes except quiet (#4618, @aalekseyev)

• Report accurate process timing information in trace mode (enabled with --trace-file) (#4517, @rgrinberg)

• Do not log live_words and free_words in trace file. This allows using Gc.quick_stat which does not scan the heap. (#4643, @emillon)

• Don't let command run by Dune observe the environment variable INSIDE_EMACS in order to improve reproducibility (#4680, @jeremiedimino)

• Fix root_module when used in public libraries (#4685, fixes #4684, @rgrinberg, @CraigFe)

• Fix root_module when used with preprocessing (#4683, fixes #4682, @rgrinberg, @CraigFe)

• Display Coq profile flags in dune printenv (#4767, @ejgallego)

• Introduce mdx stanza 0.2, requiring mdx >= 1.9.0, with a new generic deps field and the possibility to statically link libraries in the test executable. (#3956, #5391, fixes #3955)

• Improve lookup of optional or disabled binaries. Previously, we'd treat every executable with missing libraries as optional. Now, we treat make sure to look at the library's optional or enabled_if status (#4786).

• Always use 7 char hash prefix in build info version (#4857, @jberdine, fixes #4855)

• Allow to explicitly disable/enable the use of dune subst by adding a new (subst <disable|enable>) stanza to the dune-project file. (#4864, @kit-ty-kate)

• Simplify the way dune discovers the root of the workspace. It now stops at the first dune-workspace file it encounters, and fails if it finds neither a dune-workspace nor a dune-project file (#4921, fixes #4459, @jeremiedimino)

• Dune no longer reads installed META files for libraries distributed with the compiler, instead using its own internal database. (#4946, @nojb)

• Add support for (empty_module_interface_if_absent) in executable and library stanzas. (#4955, @nojb)

• Add support for %{bin-available:...} (#4995, @jeremiedimino)

• Make sure running git or hg in a sandboxed action, such as a cram test cannot escape the sandbox and pick up some random git or mercurial repository on the file system (#4996, @jeremiedimino)

• Allow %{read:...} in more places such as (enabled_if ...) (#4994, @jeremiedimino)

• Run each action in its own process group so that we don't leave stray processes behind when killing actions (#4998, @jeremiedimino)

• Add an option expand_aliases_in_sandbox (#5003, @jeremiedimino)

• Allow to cancel the initial scan via Control+C (#4460, fixes #4364 @jeremiedimino)

• Add experimental support for directory targets (#3316, #5025, Andrey Mokhov), enabled via (using directory-targets 0.1) in dune-project.

• Delete old promote-into, promote-until-clean and promote-until-clean-into syntax (#5091, Andrey Mokhov).

• Add link_flags in the env stanza (#5215)

• Bootstrap: ignore errors when trying to remove generated files. (#5407, @damiendoligez)

Added

• Add --skip-lint, --skip-build, --skip-test and --keep-build-dir to the main command (#419, @NathanReb)
• Added support for parsing changelogs written in the style of keepachangelog.com (#421, @ifazk)

Additions

• New subcommand to resolve references (@panglesd, @lubegasimon, #812)
• Improved rendering of long signatures (@panglesd, #782)
• Handle comments attached to open statement as floating comment, instead of dropping them (@panglesd, #797)
• Empty includes (containing entirely shadowed entries) are now hidden (@panglesd, #798)

Bugs fixed

• Fix a missing Result constructor during compile. This will cause some functor arguments to have different filenames (@jonludlam, #795)
• Better memory/disk space usage when handling module alias chains (@jonludlam, #799)
• Resolving class-type paths (ie., val x : #c) (@jonludlam, #809)
• Skip top-level attributes while extracting the top comment. Fix top-comment extraction with PPX preprocessing (@jorisgio, #819)
• Better handling of @canonical tags (@jonludlam, #820)
• css: improved layout (@jonludlam, @Julow, #822)

Added

• Add support for adding language tags and metadata labels in mli files. (#339, #357, @julow, @Leonidas-from-XIV)
• Add support for running non-deterministic tests in dune MDX 0.2 stanza by setting the MDX_RUN_NON_DETERMINISTIC environment variable. (#365, #366, @Leonidas-from-XIV)

• Disable warning for deprecated Toploop functions used in dune files written in OCaml syntax. Restores 4.02 compatibility. (#5381, @nojb)

• Fix missing -linkall flag when linking library dune-sites.plugin ( #4348, @kakadu, @bobot, reported by @kakadu)

• No longer reference deprecated Toploop functions when using dune files in OCaml syntax. (#4834, fixes #4830, @nojb)

• Use the stag format API to be compatible with OCaml 5.0 (#5351, @emillon).

• Fix post-processing of dune-package (fix #4389, @strub)

Added

• Add trailing ;; to the output of toplevel phrases that were missing it. (#346, @Leonidas-from-XIV)
• Make MDX compatible with OCaml 4.14 (#356, @NathanReb)

Fixed

• Use the same output as the normal toplevel. Mdx used to carry an unsafe patch to work around a bug fixed in OCaml 4.06 and that patch would change the printed types in some corner cases. (#322, @emillon)

Removed

• Dropped compatibility with older OCaml versions. The minimal supported range is 4.08 to 4.13 now (#345, @Leonidas-from-XIV)
• Do not install deprecated mdx binary anymore (#274, @gpetiot)
• Remove deprecated rule command (#312, @gpetiot)
• Remove support for require-package label, use the mdx stanza in dune instead. This label was only used for the rule command and can now be safely removed. (#363, @Leonidas-from-XIV)

New features

• Update to odoc-parser 1.0.0 (#1843, @Julow). New syntax: code blocks can carry metadata, e.g.: {@ocaml kind=toplevel env=e1[ code ]}

• Add support for OCaml 4.14 (#304, @kit-ty-kate)
• Expand nodes before applying derivers or other inline attributes based transformation, allowing better interactions between extensions and derivers (#279, #297, @NathanReb)
• Add support for registering ppx_import as a pseudo context-free rule (#271, @NathanReb)
• Add input_name to the Expansion_context.Extension and Expansion_context.Deriver modules (#284, @tatchi)
• Improve gen_symbol to strip previous unique suffix before adding a new one (#285, @ceastlund)
• Improve name_type_params_in_td to use prefixes a, b, ... instead of v_x. (#285, @ceastlund)
• Fix a bug in type_is_recursive and really_recursive where they would consider a type declaration recursive if the type appeared inside an attribute payload (#299, @NathanReb)

• Add support for OCaml 4.14 (#360 @kit-ty-kate)
• Document options in utop(1) manpage (#364 #365 @lindig)

Changed

• Use odoc-parser.0.9.0 (#333, @julow)

Deprecated

• Add a deprecation warning for toplevel blocks that are not terminated with ;; (#342, @Leonidas-from-XIV)

Fixed

• Fix accidental redirect of stderr to stdout (#343, @Leonidas-from-XIV)
• Remove trailing whitespaces that were added to indent empty lines (#341, @gpetiot)

• Fallback on dnf if yum does not exist on RHEL-based systems [#4825 @kit-ty-kate]
• Use --no-depexts in CLI 2.0 mode [#4908 @dra27]
• bootstrap: update ocaml version (fixes the compilation of opam with mingw) [#4927 @kit-ty-kate]

• Add support for 4.14 (#119, @kit-ty-kate)

Deprecated

• Profiles compact and sparse are now deprecated and will be removed by version 1.0 (#1803, @gpetiot)
• Options that are not set by the preset profiles are now deprecated and will be removed by version 1.0:
  • align-cases, align-constructors-decl and align-variants-decl (#1793, @gpetiot)
  • disambiguate-non-breaking-match (#1805, @gpetiot)
  • break-before-in (#1888, @gpetiot)
  • break-cases={toplevel,all} (#1890, @gpetiot)
  • break-collection-expressions (#1891, @gpetiot)
  • break-fun-decl=smart (#1892, @gpetiot)
  • break-fun-sig=smart (#1893, @gpetiot)
  • break-string-literals (#1894, @gpetiot)
  • break-struct (#1895, @gpetiot)
  • extension-indent (#1896, @gpetiot)
  • function-indent (#1897, @gpetiot)
  • function-indent-nested (#1898, @gpetiot)
  • if-then-else={fit-or-vertical,k-r} (#1899, @gpetiot)
  • indicate-multiline-delimiters=closing-on-separate-line (#1900, @gpetiot)
  • indent-after-in (#1901, @gpetiot)
  • let-binding-indent (#1902, @gpetiot)
  • let-binding-spacing=sparse (#1903, @gpetiot)
  • match-indent (#1904, @gpetiot)
  • match-indent-nested (#1905, @gpetiot)
  • module-item-spacing=preserve (#1906, @gpetiot)
  • nested-match (#1907, @gpetiot)
  • parens-tuple-patterns (#1908, @gpetiot)
  • sequence-style=before (#1909, @gpetiot)
  • stritem-extension-indent (#1910, @gpetiot)
  • type-decl-indent (#1911, @gpetiot)

Bug fixes

• Fix normalization of sequences of expressions (#1731, @gpetiot)
• Type constrained patterns are now always parenthesized, parentheses were missing in a class context (#1734, @gpetiot)
• Support sugared form of coercions in let bindings (#1739, @gpetiot)
• Add missing parentheses around constructor used as indexing op (#1740, @gpetiot)
• Honour .ocamlformat-ignore on Windows (#1752, @nojb)
• Avoid normalizing newlines inside quoted strings {|...|} (#1754, @nojb, @hhugo)
• Fix quadratic behavior when certain constructs are nested. This corresponds to the cases where a partial layout is triggered to determine if a construct fits on a single line for example. (#1750, #1766, @emillon)
• Fix non stabilizing comments after infix operators (*, %, #-ops) (#1776, @gpetiot)
• Fix excessive break and wrong indentation after a short-open when indicate-multiline-delimiters=closing-on-separate-line (#1786, @gpetiot)
• Add parentheses around type alias used as type constraint (#1801, @gpetiot)
• Fix alignment of comments inside a tuple pattern and remove incorrect linebreak. Fix formatting of labelled arguments containing comments. (#1797, @gpetiot)
• Emacs: only hook ocamlformat mode on tuareg/caml modes when ocamlformat is not disabled (#1814, @gpetiot)
• Fix boxing of labelled arguments, avoid having a linebreak after a label when the argument has a comment attached (#1830, #1885, @gpetiot)
• Add missing parentheses around application of prefix op when applied to other operands (#1825, @gpetiot)
• Fix application of a monadic binding when 'break-infix-before-func=false' (#1849, @gpetiot)
• Fix dropped comments attached to a sequence in a sugared extension node (#1853, @gpetiot)
• Fix formatting of exception types, and add missing parentheses (#1873, @gpetiot)
• Fix indentation of with-type constraints (#1883, @gpetiot)
• Preserve sugared syntax of extension points with attributes (#1913, @gpetiot)
• Improve comment attachment when followed but not preceded by a linebreak (#1926, @gpetiot)
• Fix position of comments preceding Pmod_ident (#1939, @gpetiot)
• Make the formatting of attributes and docstrings more consistent (#1929, @gpetiot)
• Fix stabilization of comments inside attributes (#1942, @gpetiot)

Changes

• Set 'module-item-spacing=compact' in the default/conventional profile (#1848, @gpetiot)
• Preserve bracketed lists in the Parsetree (#1694, #1876, #1914, @gpetiot)
• Line directives now cause OCamlFormat to emit an error, they were previously silently ignored (#1845, @gpetiot)
• Apply option 'module-item-spacing' on mutually recursive type declarations for more consistency (#1854, @gpetiot)

New features

• Handle merlin typed holes (#1698, @gpetiot)
• Handle punned labelled arguments with type constraint in function applications. For example, function application of the form foo ~(x:int) instead of the explicit foo ~x:(x:int). (ocaml#10434) (#1756, #1759, @gpetiot). This syntax is only produced when the output syntax is at least OCaml 4.14.
• Allow explicit binders for type variables (ocaml#10437) (#1757, @gpetiot)
• Add a new ocaml-version option to select the version of OCaml syntax of the output (#1759, @gpetiot)
• Allow disambiguated global identifiers (like t/2) so they can be formatted by tools like OCaml-LSP (#1716, @let-def)
• Handle let operator punning uniformly with other punning forms. Normalizes let operator to the punned form where possible, if output syntax version is at least OCaml 4.13.0. (#1834, #1846, @jberdine)
• Remove unnecessary surrounding parentheses for immediate objects. This syntax is only produced when the output syntax is at least OCaml 4.14. (#1934, @gpetiot)

Additions

• Compatibility with OCaml 4.14 (@patricoferris, @kit-ty-kate, #788)