diff options
-rw-r--r-- | .github/labeler.yml | 17 | ||||
-rw-r--r-- | .gitignore | 3 | ||||
-rw-r--r-- | .version | 2 | ||||
-rw-r--r-- | configure.ac | 15 | ||||
-rw-r--r-- | doc/manual/generate-xp-features-shortlist.nix | 9 | ||||
-rw-r--r-- | doc/manual/generate-xp-features.nix | 11 | ||||
-rw-r--r-- | doc/manual/local.mk | 23 | ||||
-rw-r--r-- | doc/manual/src/SUMMARY.md.in | 1 | ||||
-rw-r--r-- | doc/manual/src/contributing/experimental-features.md | 4 | ||||
-rw-r--r-- | doc/manual/src/release-notes/rl-2.15.md | 58 | ||||
-rw-r--r-- | doc/manual/src/release-notes/rl-next.md | 56 | ||||
-rw-r--r-- | doc/manual/utils.nix | 9 | ||||
-rw-r--r-- | flake.nix | 1 | ||||
-rw-r--r-- | src/libexpr/flake/lockfile.cc | 5 | ||||
-rw-r--r-- | src/libexpr/flake/lockfile.hh | 3 | ||||
-rw-r--r-- | src/libutil/config.cc | 16 | ||||
-rw-r--r-- | src/libutil/config.hh | 19 | ||||
-rw-r--r-- | src/libutil/experimental-features.cc | 241 | ||||
-rw-r--r-- | src/libutil/experimental-features.hh | 42 | ||||
-rw-r--r-- | src/libutil/util.hh | 10 | ||||
-rw-r--r-- | src/nix/main.cc | 5 | ||||
-rw-r--r-- | tests/experimental-features.sh | 42 | ||||
-rw-r--r-- | tests/nix-profile.sh | 1 |
23 files changed, 454 insertions, 139 deletions
diff --git a/.github/labeler.yml b/.github/labeler.yml index dc502b6d5..fce0d3aeb 100644 --- a/.github/labeler.yml +++ b/.github/labeler.yml @@ -2,5 +2,22 @@ - doc/manual/* - src/nix/**/*.md +"store": + - src/libstore/store-api.* + - src/libstore/*-store.* + +"fetching": + - src/libfetchers/**/* + +"repl": + - src/libcmd/repl.* + - src/nix/repl.* + +"new-cli": + - src/nix/**/* + "tests": + # Unit tests + - src/*/tests/**/* + # Functional and integration tests - tests/**/* diff --git a/.gitignore b/.gitignore index e326966d6..8ceff4ef2 100644 --- a/.gitignore +++ b/.gitignore @@ -19,9 +19,12 @@ perl/Makefile.config /doc/manual/nix.json /doc/manual/conf-file.json /doc/manual/builtins.json +/doc/manual/xp-features.json /doc/manual/src/SUMMARY.md /doc/manual/src/command-ref/new-cli /doc/manual/src/command-ref/conf-file.md +/doc/manual/src/command-ref/experimental-features-shortlist.md +/doc/manual/src/contributing/experimental-feature-descriptions.md /doc/manual/src/language/builtins.md # /scripts/ @@ -1 +1 @@ -2.15.0
\ No newline at end of file +2.16.0 diff --git a/configure.ac b/configure.ac index f1f45f868..e587bd563 100644 --- a/configure.ac +++ b/configure.ac @@ -289,13 +289,24 @@ PKG_CHECK_MODULES([GTEST], [gtest_main]) # Look for rapidcheck. +AC_ARG_VAR([RAPIDCHECK_HEADERS], [include path of gtest headers shipped by RAPIDCHECK]) # No pkg-config yet, https://github.com/emil-e/rapidcheck/issues/302 AC_LANG_PUSH(C++) AC_SUBST(RAPIDCHECK_HEADERS) [CXXFLAGS="-I $RAPIDCHECK_HEADERS $CXXFLAGS"] +[LIBS="-lrapidcheck -lgtest $LIBS"] AC_CHECK_HEADERS([rapidcheck/gtest.h], [], [], [#include <gtest/gtest.h>]) -dnl No good for C++ libs with mangled symbols -dnl AC_CHECK_LIB([rapidcheck], []) +dnl AC_CHECK_LIB doesn't work for C++ libs with mangled symbols +AC_LINK_IFELSE([ + AC_LANG_PROGRAM([[ + #include <gtest/gtest.h> + #include <rapidcheck/gtest.h> + ]], [[ + return RUN_ALL_TESTS(); + ]]) + ], + [], + [AC_MSG_ERROR([librapidcheck is not found.])]) AC_LANG_POP(C++) fi diff --git a/doc/manual/generate-xp-features-shortlist.nix b/doc/manual/generate-xp-features-shortlist.nix new file mode 100644 index 000000000..30e211c96 --- /dev/null +++ b/doc/manual/generate-xp-features-shortlist.nix @@ -0,0 +1,9 @@ +with builtins; +with import ./utils.nix; + +let + showExperimentalFeature = name: doc: + '' + - [`${name}`](@docroot@/contributing/experimental-features.md#xp-feature-${name}) + ''; +in xps: indent " " (concatStrings (attrValues (mapAttrs showExperimentalFeature xps))) diff --git a/doc/manual/generate-xp-features.nix b/doc/manual/generate-xp-features.nix new file mode 100644 index 000000000..adb94355c --- /dev/null +++ b/doc/manual/generate-xp-features.nix @@ -0,0 +1,11 @@ +with builtins; +with import ./utils.nix; + +let + showExperimentalFeature = name: doc: + squash '' + ## [`${name}`]{#xp-feature-${name}} + + ${doc} + ''; +in xps: (concatStringsSep "\n" (attrValues (mapAttrs showExperimentalFeature xps))) diff --git a/doc/manual/local.mk b/doc/manual/local.mk index df941d460..63e7e61e4 100644 --- a/doc/manual/local.mk +++ b/doc/manual/local.mk @@ -81,19 +81,20 @@ $(d)/%.8: $(d)/src/command-ref/%.md $(d)/nix.conf.5: $(d)/src/command-ref/conf-file.md @printf "Title: %s\n\n" "$$(basename $@ .5)" > $^.tmp @cat $^ >> $^.tmp + @$(call process-includes,$^,$^.tmp) $(trace-gen) lowdown -sT man --nroff-nolinks -M section=5 $^.tmp -o $@ @rm $^.tmp -$(d)/src/SUMMARY.md: $(d)/src/SUMMARY.md.in $(d)/src/command-ref/new-cli +$(d)/src/SUMMARY.md: $(d)/src/SUMMARY.md.in $(d)/src/command-ref/new-cli $(d)/src/contributing/experimental-feature-descriptions.md @cp $< $@ @$(call process-includes,$@,$@) -$(d)/src/command-ref/new-cli: $(d)/nix.json $(d)/generate-manpage.nix $(bindir)/nix +$(d)/src/command-ref/new-cli: $(d)/nix.json $(d)/utils.nix $(d)/generate-manpage.nix $(bindir)/nix @rm -rf $@ $@.tmp $(trace-gen) $(nix-eval) --write-to $@.tmp --expr 'import doc/manual/generate-manpage.nix (builtins.readFile $<)' @mv $@.tmp $@ -$(d)/src/command-ref/conf-file.md: $(d)/conf-file.json $(d)/utils.nix $(d)/src/command-ref/conf-file-prefix.md $(bindir)/nix +$(d)/src/command-ref/conf-file.md: $(d)/conf-file.json $(d)/utils.nix $(d)/src/command-ref/conf-file-prefix.md $(d)/src/command-ref/experimental-features-shortlist.md $(bindir)/nix @cat doc/manual/src/command-ref/conf-file-prefix.md > $@.tmp $(trace-gen) $(nix-eval) --expr '(import doc/manual/utils.nix).showSettings { useAnchors = true; } (builtins.fromJSON (builtins.readFile $<))' >> $@.tmp; @mv $@.tmp $@ @@ -106,6 +107,20 @@ $(d)/conf-file.json: $(bindir)/nix $(trace-gen) $(dummy-env) $(bindir)/nix show-config --json --experimental-features nix-command > $@.tmp @mv $@.tmp $@ +$(d)/src/contributing/experimental-feature-descriptions.md: $(d)/xp-features.json $(d)/utils.nix $(d)/generate-xp-features.nix $(bindir)/nix + @rm -rf $@ $@.tmp + $(trace-gen) $(nix-eval) --write-to $@.tmp --expr 'import doc/manual/generate-xp-features.nix (builtins.fromJSON (builtins.readFile $<))' + @mv $@.tmp $@ + +$(d)/src/command-ref/experimental-features-shortlist.md: $(d)/xp-features.json $(d)/utils.nix $(d)/generate-xp-features-shortlist.nix $(bindir)/nix + @rm -rf $@ $@.tmp + $(trace-gen) $(nix-eval) --write-to $@.tmp --expr 'import doc/manual/generate-xp-features-shortlist.nix (builtins.fromJSON (builtins.readFile $<))' + @mv $@.tmp $@ + +$(d)/xp-features.json: $(bindir)/nix + $(trace-gen) $(dummy-env) NIX_PATH=nix/corepkgs=corepkgs $(bindir)/nix __dump-xp-features > $@.tmp + @mv $@.tmp $@ + $(d)/src/language/builtins.md: $(d)/builtins.json $(d)/generate-builtins.nix $(d)/src/language/builtins-prefix.md $(bindir)/nix @cat doc/manual/src/language/builtins-prefix.md > $@.tmp $(trace-gen) $(nix-eval) --expr 'import doc/manual/generate-builtins.nix (builtins.fromJSON (builtins.readFile $<))' >> $@.tmp; @@ -145,7 +160,7 @@ doc/manual/generated/man1/nix3-manpages: $(d)/src/command-ref/new-cli done @touch $@ -$(docdir)/manual/index.html: $(MANUAL_SRCS) $(d)/book.toml $(d)/anchors.jq $(d)/custom.css $(d)/src/SUMMARY.md $(d)/src/command-ref/new-cli $(d)/src/command-ref/conf-file.md $(d)/src/language/builtins.md +$(docdir)/manual/index.html: $(MANUAL_SRCS) $(d)/book.toml $(d)/anchors.jq $(d)/custom.css $(d)/src/SUMMARY.md $(d)/src/command-ref/new-cli $(d)/src/contributing/experimental-feature-descriptions.md $(d)/src/command-ref/conf-file.md $(d)/src/language/builtins.md $(trace-gen) \ tmp="$$(mktemp -d)"; \ cp -r doc/manual "$$tmp"; \ diff --git a/doc/manual/src/SUMMARY.md.in b/doc/manual/src/SUMMARY.md.in index 5bf274550..f783d5908 100644 --- a/doc/manual/src/SUMMARY.md.in +++ b/doc/manual/src/SUMMARY.md.in @@ -99,6 +99,7 @@ - [CLI guideline](contributing/cli-guideline.md) - [Release Notes](release-notes/release-notes.md) - [Release X.Y (202?-??-??)](release-notes/rl-next.md) + - [Release 2.15 (2023-04-11)](release-notes/rl-2.15.md) - [Release 2.14 (2023-02-28)](release-notes/rl-2.14.md) - [Release 2.13 (2023-01-17)](release-notes/rl-2.13.md) - [Release 2.12 (2022-12-06)](release-notes/rl-2.12.md) diff --git a/doc/manual/src/contributing/experimental-features.md b/doc/manual/src/contributing/experimental-features.md index f1db22751..ad5cffa91 100644 --- a/doc/manual/src/contributing/experimental-features.md +++ b/doc/manual/src/contributing/experimental-features.md @@ -89,3 +89,7 @@ However they serve different purposes: It is primarily an issue of *design* and *communication*, targeting the broader community. This means that experimental features and RFCs are orthogonal mechanisms, and can be used independently or together as needed. + +# Currently available experimental features + +{{#include ./experimental-feature-descriptions.md}} diff --git a/doc/manual/src/release-notes/rl-2.15.md b/doc/manual/src/release-notes/rl-2.15.md new file mode 100644 index 000000000..133121999 --- /dev/null +++ b/doc/manual/src/release-notes/rl-2.15.md @@ -0,0 +1,58 @@ +# Release 2.15 (2023-04-11) + +* Commands which take installables on the command line can now read them from the standard input if + passed the `--stdin` flag. This is primarily useful when you have a large amount of paths which + exceed the OS argument limit. + +* The `nix-hash` command now supports Base64 and SRI. Use the flags `--base64` + or `--sri` to specify the format of output hash as Base64 or SRI, and `--to-base64` + or `--to-sri` to convert a hash to Base64 or SRI format, respectively. + + As the choice of hash formats is no longer binary, the `--base16` flag is also added + to explicitly specify the Base16 format, which is still the default. + +* The special handling of an [installable](../command-ref/new-cli/nix.md#installables) with `.drv` suffix being interpreted as all of the given [store derivation](../glossary.md#gloss-store-derivation)'s output paths is removed, and instead taken as the literal store path that it represents. + + The new `^` syntax for store paths introduced in Nix 2.13 allows explicitly referencing output paths of a derivation. + Using this is better and more clear than relying on the now-removed `.drv` special handling. + + For example, + ```shell-session + $ nix path-info /nix/store/gzaflydcr6sb3567hap9q6srzx8ggdgg-glibc-2.33-78.drv + ``` + + now gives info about the derivation itself, while + + ```shell-session + $ nix path-info /nix/store/gzaflydcr6sb3567hap9q6srzx8ggdgg-glibc-2.33-78.drv^* + ``` + provides information about each of its outputs. + +* The experimental command `nix describe-stores` has been removed. + +* Nix stores and their settings are now documented in [`nix help-stores`](@docroot@/command-ref/new-cli/nix3-help-stores.md). + +* Documentation for operations of `nix-store` and `nix-env` are now available on separate pages of the manual. + They include all common options that can be specified and common environment variables that affect these commands. + + These pages can be viewed offline with `man` using + + * `man nix-store-<operation>` and `man nix-env-<operation>` + * `nix-store --help --<operation>` and `nix-env --help --<operation>`. + +* Nix when used as a client now checks whether the store (the server) trusts the client. + (The store always had to check whether it trusts the client, but now the client is informed of the store's decision.) + This is useful for scripting interactions with (non-legacy-ssh) remote Nix stores. + + `nix store ping` and `nix doctor` now display this information. + +* The new command `nix derivation add` allows adding derivations to the store without involving the Nix language. + It exists to round out our collection of basic utility/plumbing commands, and allow for a low barrier-to-entry way of experimenting with alternative front-ends to the Nix Store. + It uses the same JSON layout as `nix derivation show`, and is its inverse. + +* `nix show-derivation` has been renamed to `nix derivation show`. + This matches `nix derivation add`, and avoids bloating the top-level namespace. + The old name is still kept as an alias for compatibility, however. + +* The `nix derivation {add,show}` JSON format now includes the derivation name as a top-level field. + This is useful in general, but especially necessary for the `add` direction, as otherwise we would need to pass in the name out of band for certain cases. diff --git a/doc/manual/src/release-notes/rl-next.md b/doc/manual/src/release-notes/rl-next.md index 5b62836bf..78ae99f4b 100644 --- a/doc/manual/src/release-notes/rl-next.md +++ b/doc/manual/src/release-notes/rl-next.md @@ -1,58 +1,2 @@ # Release X.Y (202?-??-??) -* Commands which take installables on the command line can now read them from the standard input if - passed the `--stdin` flag. This is primarily useful when you have a large amount of paths which - exceed the OS arg limit. - -* The `nix-hash` command now supports Base64 and SRI. Use the flags `--base64` - or `--sri` to specify the format of output hash as Base64 or SRI, and `--to-base64` - or `--to-sri` to convert a hash to Base64 or SRI format, respectively. - - As the choice of hash formats is no longer binary, the `--base16` flag is also added - to explicitly specify the Base16 format, which is still the default. - -* The special handling of an [installable](../command-ref/new-cli/nix.md#installables) with `.drv` suffix being interpreted as all of the given [store derivation](../glossary.md#gloss-store-derivation)'s output paths is removed, and instead taken as the literal store path that it represents. - - The new `^` syntax for store paths introduced in Nix 2.13 allows explicitly referencing output paths of a derivation. - Using this is better and more clear than relying on the now-removed `.drv` special handling. - - For example, - ```shell-session - $ nix path-info /nix/store/gzaflydcr6sb3567hap9q6srzx8ggdgg-glibc-2.33-78.drv - ``` - - now gives info about the derivation itself, while - - ```shell-session - $ nix path-info /nix/store/gzaflydcr6sb3567hap9q6srzx8ggdgg-glibc-2.33-78.drv^* - ``` - provides information about each of its outputs. - -* The experimental command `nix describe-stores` has been removed. - -* Nix stores and their settings are now documented in [`nix help-stores`](@docroot@/command-ref/new-cli/nix3-help-stores.md). - -* Documentation for operations of `nix-store` and `nix-env` are now available on separate pages of the manual. - They include all common options that can be specified and common environment variables that affect these commands. - - These pages can be viewed offline with `man` using - - * `man nix-store-<operation>` and `man nix-env-<operation>` - * `nix-store --help --<operation>` and `nix-env --help --<operation>`. - -* Nix when used as a client now checks whether the store (the server) trusts the client. - (The store always had to check whether it trusts the client, but now the client is informed of the store's decision.) - This is useful for scripting interactions with (non-legacy-ssh) remote Nix stores. - - `nix store ping` and `nix doctor` now display this information. - -* A new command `nix derivation add` is created, to allow adding derivations to the store without involving the Nix language. - It exists to round out our collection of basic utility/plumbing commands, and allow for a low barrier-to-entry way of experimenting with alternative front-ends to the Nix Store. - It uses the same JSON layout as `nix show-derivation`, and is its inverse. - -* `nix show-derivation` has been renamed to `nix derivation show`. - This matches `nix derivation add`, and avoids bloating the top-level namespace. - The old name is still kept as an alias for compatibility, however. - -* The `nix derivation {add,show}` JSON format now includes the derivation name as a top-level field. - This is useful in general, but especially necessary for the `add` direction, as otherwise we would need to pass in the name out of band for certain cases. diff --git a/doc/manual/utils.nix b/doc/manual/utils.nix index 5eacce0dd..82544935a 100644 --- a/doc/manual/utils.nix +++ b/doc/manual/utils.nix @@ -5,6 +5,9 @@ rec { concatStrings = concatStringsSep ""; + attrsToList = a: + map (name: { inherit name; value = a.${name}; }) (builtins.attrNames a); + replaceStringsRec = from: to: string: # recursively replace occurrences of `from` with `to` within `string` # example: @@ -74,10 +77,10 @@ rec { if aliases == [] then "" else "**Deprecated alias:** ${(concatStringsSep ", " (map (s: "`${s}`") aliases))}"; - indent = prefix: s: - concatStringsSep "\n" (map (x: if x == "" then x else "${prefix}${x}") (splitLines s)); - in result; + indent = prefix: s: + concatStringsSep "\n" (map (x: if x == "" then x else "${prefix}${x}") (splitLines s)); + showSettings = args: settingsInfo: concatStrings (attrValues (mapAttrs (showSetting args) settingsInfo)); } @@ -219,6 +219,7 @@ enableParallelBuilding = true; + configureFlags = testConfigureFlags; # otherwise configure fails dontBuild = true; doInstallCheck = true; diff --git a/src/libexpr/flake/lockfile.cc b/src/libexpr/flake/lockfile.cc index a74e68c9c..ba2fd46f0 100644 --- a/src/libexpr/flake/lockfile.cc +++ b/src/libexpr/flake/lockfile.cc @@ -234,6 +234,11 @@ bool LockFile::operator ==(const LockFile & other) const return toJSON() == other.toJSON(); } +bool LockFile::operator !=(const LockFile & other) const +{ + return !(*this == other); +} + InputPath parseInputPath(std::string_view s) { InputPath path; diff --git a/src/libexpr/flake/lockfile.hh b/src/libexpr/flake/lockfile.hh index 0ac731b5d..ba4c0c848 100644 --- a/src/libexpr/flake/lockfile.hh +++ b/src/libexpr/flake/lockfile.hh @@ -73,6 +73,9 @@ struct LockFile std::optional<FlakeRef> isUnlocked() const; bool operator ==(const LockFile & other) const; + // Needed for old gcc versions that don't synthesize it (like gcc 8.2.2 + // that is still the default on aarch64-linux) + bool operator !=(const LockFile & other) const; std::shared_ptr<Node> findInput(const InputPath & path); diff --git a/src/libutil/config.cc b/src/libutil/config.cc index 8d63536d6..5ff8d91ba 100644 --- a/src/libutil/config.cc +++ b/src/libutil/config.cc @@ -70,17 +70,10 @@ void AbstractConfig::reapplyUnknownSettings() set(s.first, s.second); } -// Whether we should process the option. Excludes aliases, which are handled elsewhere, and disabled features. -static bool applicable(const Config::SettingData & sd) -{ - return !sd.isAlias - && experimentalFeatureSettings.isEnabled(sd.setting->experimentalFeature); -} - void Config::getSettings(std::map<std::string, SettingInfo> & res, bool overriddenOnly) { for (auto & opt : _settings) - if (applicable(opt.second) && (!overriddenOnly || opt.second.setting->overridden)) + if (!opt.second.isAlias && (!overriddenOnly || opt.second.setting->overridden)) res.emplace(opt.first, SettingInfo{opt.second.setting->to_string(), opt.second.setting->description}); } @@ -154,7 +147,7 @@ nlohmann::json Config::toJSON() { auto res = nlohmann::json::object(); for (auto & s : _settings) - if (applicable(s.second)) + if (!s.second.isAlias) res.emplace(s.first, s.second.setting->toJSON()); return res; } @@ -163,7 +156,7 @@ std::string Config::toKeyValue() { auto res = std::string(); for (auto & s : _settings) - if (applicable(s.second)) + if (s.second.isAlias) res += fmt("%s = %s\n", s.first, s.second.setting->to_string()); return res; } @@ -171,9 +164,6 @@ std::string Config::toKeyValue() void Config::convertToArgs(Args & args, const std::string & category) { for (auto & s : _settings) { - /* We do include args for settings gated on disabled - experimental-features. The args themselves however will also be - gated on any experimental feature the underlying setting is. */ if (!s.second.isAlias) s.second.setting->convertToArg(args, category); } diff --git a/src/libutil/config.hh b/src/libutil/config.hh index 3c1d70294..162626791 100644 --- a/src/libutil/config.hh +++ b/src/libutil/config.hh @@ -371,8 +371,23 @@ extern GlobalConfig globalConfig; struct ExperimentalFeatureSettings : Config { - Setting<std::set<ExperimentalFeature>> experimentalFeatures{this, {}, "experimental-features", - "Experimental Nix features to enable."}; + Setting<std::set<ExperimentalFeature>> experimentalFeatures{ + this, {}, "experimental-features", + R"( + Experimental features that are enabled. + + Example: + + ``` + experimental-features = nix-command flakes + ``` + + The following experimental features are available: + + {{#include experimental-features-shortlist.md}} + + Experimental features are [further documented in the manual](@docroot@/contributing/experimental-features.md). + )"}; /** * Check whether the given experimental feature is enabled. diff --git a/src/libutil/experimental-features.cc b/src/libutil/experimental-features.cc index 32aa66db1..be5a2c088 100644 --- a/src/libutil/experimental-features.cc +++ b/src/libutil/experimental-features.cc @@ -5,30 +5,218 @@ namespace nix { -std::map<ExperimentalFeature, std::string> stringifiedXpFeatures = { - { Xp::CaDerivations, "ca-derivations" }, - { Xp::ImpureDerivations, "impure-derivations" }, - { Xp::Flakes, "flakes" }, - { Xp::NixCommand, "nix-command" }, - { Xp::RecursiveNix, "recursive-nix" }, - { Xp::NoUrlLiterals, "no-url-literals" }, - { Xp::FetchClosure, "fetch-closure" }, - { Xp::ReplFlake, "repl-flake" }, - { Xp::AutoAllocateUids, "auto-allocate-uids" }, - { Xp::Cgroups, "cgroups" }, - { Xp::DiscardReferences, "discard-references" }, - { Xp::NixTesting, "nix-testing" }, +struct ExperimentalFeatureDetails +{ + ExperimentalFeature tag; + std::string_view name; + std::string_view description; }; +constexpr std::array<ExperimentalFeatureDetails, 12> xpFeatureDetails = {{ + { + .tag = Xp::CaDerivations, + .name = "ca-derivations", + .description = R"( + Allow derivations to be content-addressed in order to prevent + rebuilds when changes to the derivation do not result in changes to + the derivation's output. See + [__contentAddressed](@docroot@/language/advanced-attributes.md#adv-attr-__contentAddressed) + for details. + )", + }, + { + .tag = Xp::ImpureDerivations, + .name = "impure-derivations", + .description = R"( + Allow derivations to produce non-fixed outputs by setting the + `__impure` derivation attribute to `true`. An impure derivation can + have differing outputs each time it is built. + + Example: + + ``` + derivation { + name = "impure"; + builder = /bin/sh; + __impure = true; # mark this derivation as impure + args = [ "-c" "read -n 10 random < /dev/random; echo $random > $out" ]; + system = builtins.currentSystem; + } + ``` + + Each time this derivation is built, it can produce a different + output (as the builder outputs random bytes to `$out`). Impure + derivations also have access to the network, and only fixed-output + or other impure derivations can rely on impure derivations. Finally, + an impure derivation cannot also be + [content-addressed](#xp-feature-ca-derivations). + )", + }, + { + .tag = Xp::Flakes, + .name = "flakes", + .description = R"( + Enable flakes. See the manual entry for [`nix + flake`](@docroot@/command-ref/new-cli/nix3-flake.md) for details. + )", + }, + { + .tag = Xp::NixCommand, + .name = "nix-command", + .description = R"( + Enable the new `nix` subcommands. See the manual on + [`nix`](@docroot@/command-ref/new-cli/nix.md) for details. + )", + }, + { + .tag = Xp::RecursiveNix, + .name = "recursive-nix", + .description = R"( + Allow derivation builders to call Nix, and thus build derivations + recursively. + + Example: + + ``` + with import <nixpkgs> {}; + + runCommand "foo" + { + buildInputs = [ nix jq ]; + NIX_PATH = "nixpkgs=${<nixpkgs>}"; + } + '' + hello=$(nix-build -E '(import <nixpkgs> {}).hello.overrideDerivation (args: { name = "recursive-hello"; })') + + mkdir -p $out/bin + ln -s $hello/bin/hello $out/bin/hello + '' + ``` + + An important restriction on recursive builders is disallowing + arbitrary substitutions. For example, running + + ``` + nix-store -r /nix/store/kmwd1hq55akdb9sc7l3finr175dajlby-hello-2.10 + ``` + + in the above `runCommand` script would be disallowed, as this could + lead to derivations with hidden dependencies or breaking + reproducibility by relying on the current state of the Nix store. An + exception would be if + `/nix/store/kmwd1hq55akdb9sc7l3finr175dajlby-hello-2.10` were + already in the build inputs or built by a previous recursive Nix + call. + )", + }, + { + .tag = Xp::NoUrlLiterals, + .name = "no-url-literals", + .description = R"( + Disallow unquoted URLs as part of the Nix language syntax. The Nix + language allows for URL literals, like so: + + ``` + $ nix repl + Welcome to Nix 2.15.0. Type :? for help. + + nix-repl> http://foo + "http://foo" + ``` + + But enabling this experimental feature will cause the Nix parser to + throw an error when encountering a URL literal: + + ``` + $ nix repl --extra-experimental-features 'no-url-literals' + Welcome to Nix 2.15.0. Type :? for help. + + nix-repl> http://foo + error: URL literals are disabled + + at «string»:1:1: + + 1| http://foo + | ^ + + ``` + + While this is currently an experimental feature, unquoted URLs are + being deprecated and their usage is discouraged. + + The reason is that, as opposed to path literals, URLs have no + special properties that distinguish them from regular strings, URLs + containing parameters have to be quoted anyway, and unquoted URLs + may confuse external tooling. + )", + }, + { + .tag = Xp::FetchClosure, + .name = "fetch-closure", + .description = R"( + Enable the use of the [`fetchClosure`](@docroot@/language/builtins.md#builtins-fetchClosure) built-in function in the Nix language. + )", + }, + { + .tag = Xp::ReplFlake, + .name = "repl-flake", + .description = R"( + Allow passing [installables](@docroot@/command-ref/new-cli/nix.md#installables) to `nix repl`, making its interface consistent with the other experimental commands. + )", + }, + { + .tag = Xp::AutoAllocateUids, + .name = "auto-allocate-uids", + .description = R"( + Allows Nix to automatically pick UIDs for builds, rather than creating + `nixbld*` user accounts. See the [`auto-allocate-uids`](#conf-auto-allocate-uids) setting for details. + )", + }, + { + .tag = Xp::Cgroups, + .name = "cgroups", + .description = R"( + Allows Nix to execute builds inside cgroups. See + the [`use-cgroups`](#conf-use-cgroups) setting for details. + )", + }, + { + .tag = Xp::DiscardReferences, + .name = "discard-references", + .description = R"( + Allow the use of the [`unsafeDiscardReferences`](@docroot@/language/advanced-attributes.html#adv-attr-unsafeDiscardReferences) attribute in derivations + that use [structured attributes](@docroot@/language/advanced-attributes.html#adv-attr-structuredAttrs). This disables scanning of outputs for + runtime dependencies. + )", + }, + { + .tag = Xp::NixTesting, + .name = "nix-testing", + .description = R"( + A "permanent" experimental feature for extra features we just need + for testing. Not actually an "experiment" in the sense of being + prospective functionality for regular users. + )", + }, +}}; + +static_assert( + []() constexpr { + for (auto [index, feature] : enumerate(xpFeatureDetails)) + if (index != (size_t)feature.tag) + return false; + return true; + }(), + "array order does not match enum tag order"); + const std::optional<ExperimentalFeature> parseExperimentalFeature(const std::string_view & name) { using ReverseXpMap = std::map<std::string_view, ExperimentalFeature>; - static auto reverseXpMap = []() - { + static std::unique_ptr<ReverseXpMap> reverseXpMap = []() { auto reverseXpMap = std::make_unique<ReverseXpMap>(); - for (auto & [feature, name] : stringifiedXpFeatures) - (*reverseXpMap)[name] = feature; + for (auto & xpFeature : xpFeatureDetails) + (*reverseXpMap)[xpFeature.name] = xpFeature.tag; return reverseXpMap; }(); @@ -38,20 +226,27 @@ const std::optional<ExperimentalFeature> parseExperimentalFeature(const std::str return std::nullopt; } -std::string_view showExperimentalFeature(const ExperimentalFeature feature) +std::string_view showExperimentalFeature(const ExperimentalFeature tag) +{ + assert((size_t)tag < xpFeatureDetails.size()); + return xpFeatureDetails[(size_t)tag].name; +} + +nlohmann::json documentExperimentalFeatures() { - const auto ret = get(stringifiedXpFeatures, feature); - assert(ret); - return *ret; + StringMap res; + for (auto & xpFeature : xpFeatureDetails) + res[std::string { xpFeature.name }] = + trim(stripIndentation(xpFeature.description)); + return (nlohmann::json) res; } std::set<ExperimentalFeature> parseFeatures(const std::set<std::string> & rawFeatures) { std::set<ExperimentalFeature> res; - for (auto & rawFeature : rawFeatures) { + for (auto & rawFeature : rawFeatures) if (auto feature = parseExperimentalFeature(rawFeature)) res.insert(*feature); - } return res; } diff --git a/src/libutil/experimental-features.hh b/src/libutil/experimental-features.hh index 6a3c929df..c41f73fa0 100644 --- a/src/libutil/experimental-features.hh +++ b/src/libutil/experimental-features.hh @@ -11,8 +11,9 @@ namespace nix { /** * The list of available experimental features. * - * If you update this, don’t forget to also change the map defining their - * string representation in the corresponding `.cc` file. + * If you update this, don’t forget to also change the map defining + * their string representation and documentation in the corresponding + * `.cc` file as well. */ enum struct ExperimentalFeature { @@ -27,11 +28,6 @@ enum struct ExperimentalFeature AutoAllocateUids, Cgroups, DiscardReferences, - - /** - * A "permanent" experimental feature for extra features we just - * need for testing. - **/ NixTesting, }; @@ -40,26 +36,52 @@ enum struct ExperimentalFeature */ using Xp = ExperimentalFeature; +/** + * Parse an experimental feature (enum value) from its name. Experimental + * feature flag names are hyphenated and do not contain spaces. + */ const std::optional<ExperimentalFeature> parseExperimentalFeature( const std::string_view & name); + +/** + * Show the name of an experimental feature. This is the opposite of + * parseExperimentalFeature(). + */ std::string_view showExperimentalFeature(const ExperimentalFeature); +/** + * Compute the documentation of all experimental features. + * + * See `doc/manual` for how this information is used. + */ +nlohmann::json documentExperimentalFeatures(); + +/** + * Shorthand for `str << showExperimentalFeature(feature)`. + */ std::ostream & operator<<( std::ostream & str, const ExperimentalFeature & feature); /** - * Parse a set of strings to the corresponding set of experimental features, - * ignoring (but warning for) any unkwown feature. + * Parse a set of strings to the corresponding set of experimental + * features, ignoring (but warning for) any unknown feature. */ std::set<ExperimentalFeature> parseFeatures(const std::set<std::string> &); +/** + * An experimental feature was required for some (experimental) + * operation, but was not enabled. + */ class MissingExperimentalFeature : public Error { public: + /** + * The experimental feature that was required but not enabled. + */ ExperimentalFeature missingFeature; - MissingExperimentalFeature(ExperimentalFeature); + MissingExperimentalFeature(ExperimentalFeature missingFeature); }; /** diff --git a/src/libutil/util.hh b/src/libutil/util.hh index 56160baaf..85ab77b1b 100644 --- a/src/libutil/util.hh +++ b/src/libutil/util.hh @@ -916,16 +916,16 @@ constexpr auto enumerate(T && iterable) { size_t i; TIter iter; - bool operator != (const iterator & other) const { return iter != other.iter; } - void operator ++ () { ++i; ++iter; } - auto operator * () const { return std::tie(i, *iter); } + constexpr bool operator != (const iterator & other) const { return iter != other.iter; } + constexpr void operator ++ () { ++i; ++iter; } + constexpr auto operator * () const { return std::tie(i, *iter); } }; struct iterable_wrapper { T iterable; - auto begin() { return iterator{ 0, std::begin(iterable) }; } - auto end() { return iterator{ 0, std::end(iterable) }; } + constexpr auto begin() { return iterator{ 0, std::begin(iterable) }; } + constexpr auto end() { return iterator{ 0, std::end(iterable) }; } }; return iterable_wrapper{ std::forward<T>(iterable) }; diff --git a/src/nix/main.cc b/src/nix/main.cc index f943f77bb..705061d25 100644 --- a/src/nix/main.cc +++ b/src/nix/main.cc @@ -375,6 +375,11 @@ void mainWrapped(int argc, char * * argv) return; } + if (argc == 2 && std::string(argv[1]) == "__dump-xp-features") { + logger->cout(documentExperimentalFeatures().dump()); + return; + } + Finally printCompletions([&]() { if (completions) { diff --git a/tests/experimental-features.sh b/tests/experimental-features.sh index a4d55f5f4..73554da8c 100644 --- a/tests/experimental-features.sh +++ b/tests/experimental-features.sh @@ -1,25 +1,27 @@ source common.sh -# Without flakes, flake options should not show up -# With flakes, flake options should show up - -function both_ways { - nix --experimental-features 'nix-command' "$@" | grepQuietInverse flake - nix --experimental-features 'nix-command flakes' "$@" | grepQuiet flake - - # Also, the order should not matter - nix "$@" --experimental-features 'nix-command' | grepQuietInverse flake - nix "$@" --experimental-features 'nix-command flakes' | grepQuiet flake -} - -# Simple case, the configuration effects the running command -both_ways show-config - -# Skipping for now, because we actually *do* want these to show up in -# the manual, just be marked experimental. Will reenable once the manual -# generation takes advantage of the JSON metadata on this. - -# both_ways store gc --help +# Skipping these two for now, because we actually *do* want flags and +# config settings to always show up in the manual, just be marked +# experimental. Will reenable once the manual generation takes advantage +# of the JSON metadata on this. +# +# # Without flakes, flake options should not show up +# # With flakes, flake options should show up +# +# function grep_both_ways { +# nix --experimental-features 'nix-command' "$@" | grepQuietInverse flake +# nix --experimental-features 'nix-command flakes' "$@" | grepQuiet flake +# +# # Also, the order should not matter +# nix "$@" --experimental-features 'nix-command' | grepQuietInverse flake +# nix "$@" --experimental-features 'nix-command flakes' | grepQuiet flake +# } +# +# # Simple case, the configuration effects the running command +# grep_both_ways show-config +# +# # Medium case, the configuration effects --help +# grep_both_ways store gc --help expect 1 nix --experimental-features 'nix-command' show-config --flake-registry 'https://no' nix --experimental-features 'nix-command flakes' show-config --flake-registry 'https://no' diff --git a/tests/nix-profile.sh b/tests/nix-profile.sh index 652e8a8f2..4ef5b484a 100644 --- a/tests/nix-profile.sh +++ b/tests/nix-profile.sh @@ -144,6 +144,7 @@ expect 1 nix profile install $flake2Dir diff -u <( nix --offline profile install $flake2Dir 2>&1 1> /dev/null \ | grep -vE "^warning: " \ + | grep -vE "^error \(ignored\): " \ || true ) <(cat << EOF error: An existing package already provides the following file: |