Merge remote-tracking branch 'upstream/master' into indexed-store-path-outputs

.github/workflows/backport.yml

@@ -8,7 +8,7 @@ jobs:
     if: github.repository_owner == 'NixOS' && github.event.pull_request.merged == true && (github.event_name != 'labeled' || startsWith('backport', github.event.label.name))
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           ref: ${{ github.event.pull_request.head.sha }}
           # required to find all branches

.github/workflows/ci.yml

@@ -14,10 +14,10 @@ jobs:
     runs-on: ${{ matrix.os }}
     timeout-minutes: 60
     steps:
-    - uses: actions/checkout@v2.4.0
+    - uses: actions/checkout@v3
       with:
         fetch-depth: 0
-    - uses: cachix/install-nix-action@v16
+    - uses: cachix/install-nix-action@v17
     - run: echo CACHIX_NAME="$(echo $GITHUB_REPOSITORY-install-tests | tr "[A-Z]/" "[a-z]-")" >> $GITHUB_ENV
     - uses: cachix/cachix-action@v10
       if: needs.check_cachix.outputs.secret == 'true'
@@ -46,11 +46,11 @@ jobs:
     outputs:
       installerURL: ${{ steps.prepare-installer.outputs.installerURL }}
     steps:
-    - uses: actions/checkout@v2.4.0
+    - uses: actions/checkout@v3
       with:
         fetch-depth: 0
     - run: echo CACHIX_NAME="$(echo $GITHUB_REPOSITORY-install-tests | tr "[A-Z]/" "[a-z]-")" >> $GITHUB_ENV
-    - uses: cachix/install-nix-action@v16
+    - uses: cachix/install-nix-action@v17
     - uses: cachix/cachix-action@v10
       with:
         name: '${{ env.CACHIX_NAME }}'
@@ -67,9 +67,9 @@ jobs:
         os: [ubuntu-latest, macos-latest]
     runs-on: ${{ matrix.os }}
     steps:
-    - uses: actions/checkout@v2.4.0
+    - uses: actions/checkout@v3
     - run: echo CACHIX_NAME="$(echo $GITHUB_REPOSITORY-install-tests | tr "[A-Z]/" "[a-z]-")" >> $GITHUB_ENV
-    - uses: cachix/install-nix-action@v16
+    - uses: cachix/install-nix-action@v17
       with:
         install_url: '${{needs.installer.outputs.installerURL}}'
         install_options: "--tarball-url-prefix https://${{ env.CACHIX_NAME }}.cachix.org/serve"
@@ -83,10 +83,10 @@ jobs:
       needs.check_cachix.outputs.secret == 'true'
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2.4.0
+    - uses: actions/checkout@v3
       with:
         fetch-depth: 0
-    - uses: cachix/install-nix-action@v16
+    - uses: cachix/install-nix-action@v17
     - run: echo CACHIX_NAME="$(echo $GITHUB_REPOSITORY-install-tests | tr "[A-Z]/" "[a-z]-")" >> $GITHUB_ENV
     - run: echo NIX_VERSION="$(nix-instantiate --eval -E '(import ./default.nix).defaultPackage.${builtins.currentSystem}.version' | tr -d \")" >> $GITHUB_ENV
     - uses: cachix/cachix-action@v10

.github/workflows/hydra_status.yml

@@ -9,7 +9,7 @@ jobs:
     if: github.repository_owner == 'NixOS'
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2.4.0
+    - uses: actions/checkout@v3
       with:
         fetch-depth: 0
     - run: bash scripts/check-hydra-status.sh

doc/manual/src/release-notes/rl-next.md

@@ -41,5 +41,9 @@
   As before, the old output will continue to work, but `nix flake check` will
   issue a warning about it.
 
+* `nix run` is now stricter wrt what it accepts:
+    * Members of `apps` are now required to be apps (as defined in [the manual](https://nixos.org/manual/nix/stable/command-ref/new-cli/nix3-run.html#apps))
+    * Member of `packages` or `legacyPackages` cannot be of type "app" when used by `nix run`.
+
 * Add experimental *indexed store derivations* installable syntax, part of the
   the `computed-derivations` experimental feature.

misc/bash/completion.sh

@@ -15,7 +15,7 @@ function _complete_nix {
         else
             COMPREPLY+=("$completion")
         fi
-    done < <(NIX_GET_COMPLETIONS=$cword "${words[@]/#\~/$HOME}" 2>/dev/null)
+    done < <(NIX_GET_COMPLETIONS=$cword "${words[@]}" 2>/dev/null)
     __ltrim_colon_completions "$cur"
 }
 

scripts/install-multi-user.sh

@@ -423,6 +423,18 @@ EOF
         fi
     done
 
+    if [ "$(uname -s)" = "Linux" ] && [ ! -e /run/systemd/system ]; then
+        warning <<EOF
+We did not detect systemd on your system. With a multi-user install
+without systemd you will have to manually configure your init system to
+launch the Nix daemon after installation.
+EOF
+        if ! ui_confirm "Do you want to proceed with a multi-user installation?"; then
+            failure <<EOF
+You have aborted the installation.
+EOF
+        fi
+    fi
 }
 
 setup_report() {

src/libcmd/command.hh

@@ -85,11 +85,12 @@ struct SourceExprCommand : virtual Args, MixFlakeOptions
 {
     std::optional<Path> file;
     std::optional<std::string> expr;
+    bool readOnlyMode = false;
 
     // FIXME: move this; not all commands (e.g. 'nix run') use it.
     OperateOn operateOn = OperateOn::Output;
 
-    SourceExprCommand();
+    SourceExprCommand(bool supportReadOnlyMode = false);
 
     std::vector<std::shared_ptr<Installable>> parseInstallables(
         ref<Store> store, std::vector<std::string> ss);
@@ -128,13 +129,13 @@ struct InstallableCommand : virtual Args, SourceExprCommand
 {
     std::shared_ptr<Installable> installable;
 
-    InstallableCommand();
+    InstallableCommand(bool supportReadOnlyMode = false);
 
     void prepare() override;
 
     std::optional<FlakeRef> getFlakeRefForCompletion() override
     {
-        return parseFlakeRef(_installable, absPath("."));
+        return parseFlakeRefWithFragment(_installable, absPath(".")).first;
     }
 
 private:

src/libcmd/common-eval-args.cc

@@ -7,6 +7,7 @@
 #include "registry.hh"
 #include "flake/flakeref.hh"
 #include "store-api.hh"
+#include "command.hh"
 
 namespace nix {
 
@@ -59,6 +60,9 @@ MixEvalArgs::MixEvalArgs()
             fetchers::Attrs extraAttrs;
             if (to.subdir != "") extraAttrs["dir"] = to.subdir;
             fetchers::overrideRegistry(from.input, to.input, extraAttrs);
+        }},
+        .completer = {[&](size_t, std::string_view prefix) {
+            completeFlakeRef(openStore(), prefix);
         }}
     });
 

src/libcmd/installables.cc

@@ -1,4 +1,6 @@
+#include "globals.hh"
 #include "installables.hh"
+#include "util.hh"
 #include "command.hh"
 #include "attr-path.hh"
 #include "common-eval-args.hh"
@@ -99,6 +101,14 @@ MixFlakeOptions::MixFlakeOptions()
             lockFlags.inputOverrides.insert_or_assign(
                 flake::parseInputPath(inputPath),
                 parseFlakeRef(flakeRef, absPath("."), true));
+        }},
+        .completer = {[&](size_t n, std::string_view prefix) {
+            if (n == 0) {
+                if (auto flakeRef = getFlakeRefForCompletion())
+                    completeFlakeInputPath(getEvalState(), *flakeRef, prefix);
+            } else if (n == 1) {
+                completeFlakeRef(getEvalState()->store, prefix);
+            }
         }}
     });
 
@@ -129,7 +139,7 @@ MixFlakeOptions::MixFlakeOptions()
     });
 }
 
-SourceExprCommand::SourceExprCommand()
+SourceExprCommand::SourceExprCommand(bool supportReadOnlyMode)
 {
     addFlag({
         .longName = "file",
@@ -157,6 +167,17 @@ SourceExprCommand::SourceExprCommand()
         .category = installablesCategory,
         .handler = {&operateOn, OperateOn::Derivation},
     });
+
+    if (supportReadOnlyMode) {
+        addFlag({
+            .longName = "read-only",
+            .description =
+                "Do not instantiate each evaluated derivation. "
+                "This improves performance, but can cause errors when accessing "
+                "store paths of derivations during evaluation.",
+            .handler = {&readOnlyMode, true},
+        });
+    }
 }
 
 Strings SourceExprCommand::getDefaultFlakeAttrPaths()
@@ -182,6 +203,8 @@ Strings SourceExprCommand::getDefaultFlakeAttrPathPrefixes()
 void SourceExprCommand::completeInstallable(std::string_view prefix)
 {
     if (file) {
+        completionType = ctAttrs;
+
         evalSettings.pureEval = false;
         auto state = getEvalState();
         Expr *e = state->parseExprFromFile(
@@ -210,13 +233,14 @@ void SourceExprCommand::completeInstallable(std::string_view prefix)
         Value v2;
         state->autoCallFunction(*autoArgs, v1, v2);
 
-        completionType = ctAttrs;
-
         if (v2.type() == nAttrs) {
             for (auto & i : *v2.attrs) {
                 std::string name = i.name;
                 if (name.find(searchWord) == 0) {
-                    completions->add(i.name);
+                    if (prefix_ == "")
+                        completions->add(name);
+                    else
+                        completions->add(prefix_ + "." + name);
                 }
             }
         }
@@ -244,10 +268,11 @@ void completeFlakeRefWithFragment(
         if (hash == std::string::npos) {
             completeFlakeRef(evalState->store, prefix);
         } else {
+            completionType = ctAttrs;
+
             auto fragment = prefix.substr(hash + 1);
             auto flakeRefS = std::string(prefix.substr(0, hash));
-            // FIXME: do tilde expansion.
+            auto flakeRef = parseFlakeRef(expandTilde(flakeRefS), absPath("."));
-            auto flakeRef = parseFlakeRef(flakeRefS, absPath("."));
 
             auto evalCache = openEvalCache(*evalState,
                 std::make_shared<flake::LockedFlake>(lockFlake(*evalState, flakeRef, lockFlags)));
@@ -259,8 +284,6 @@ void completeFlakeRefWithFragment(
                flake. */
             attrPathPrefixes.push_back("");
 
-            completionType = ctAttrs;
-
             for (auto & attrPathPrefixS : attrPathPrefixes) {
                 auto attrPathPrefix = parseAttrPath(*evalState, attrPathPrefixS);
                 auto attrPathS = attrPathPrefixS + std::string(fragment);
@@ -334,16 +357,16 @@ DerivedPath Installable::toDerivedPath()
     return std::move(buildables[0]);
 }
 
-std::vector<std::pair<std::shared_ptr<eval_cache::AttrCursor>, std::string>>
+std::vector<ref<eval_cache::AttrCursor>>
 Installable::getCursors(EvalState & state)
 {
     auto evalCache =
         std::make_shared<nix::eval_cache::EvalCache>(std::nullopt, state,
             [&]() { return toValue(state).first; });
-    return {{evalCache->getRoot(), ""}};
+    return {evalCache->getRoot()};
 }
 
-std::pair<std::shared_ptr<eval_cache::AttrCursor>, std::string>
+ref<eval_cache::AttrCursor>
 Installable::getCursor(EvalState & state)
 {
     auto cursors = getCursors(state);
@@ -586,27 +609,9 @@ InstallableFlake::InstallableFlake(
 
 std::tuple<std::string, FlakeRef, InstallableValue::DerivationInfo> InstallableFlake::toDerivation()
 {
-    auto lockedFlake = getLockedFlake();
+    auto attr = getCursor(*state);
 
-    auto cache = openEvalCache(*state, lockedFlake);
+    auto attrPath = attr->getAttrPathStr();
-    auto root = cache->getRoot();
-
-    Suggestions suggestions;
-
-    for (auto & attrPath : getActualAttrPaths()) {
-        debug("trying flake output attribute '%s'", attrPath);
-
-        auto attrOrSuggestions = root->findAlongAttrPath(
-            parseAttrPath(*state, attrPath),
-            true
-        );
-
-        if (!attrOrSuggestions) {
-            suggestions += attrOrSuggestions.getSuggestions();
-            continue;
-        }
-
-        auto attr = *attrOrSuggestions;
 
     if (!attr->isDerivation())
         throw Error("flake output attribute '%s' is not a derivation", attrPath);
@@ -618,11 +623,7 @@ std::tuple<std::string, FlakeRef, InstallableValue::DerivationInfo> InstallableF
         attr->getAttr(state->sOutputName)->getString()
     };
 
-        return {attrPath, lockedFlake->flake.lockedRef, std::move(drvInfo)};
+    return {attrPath, getLockedFlake()->flake.lockedRef, std::move(drvInfo)};
-    }
-
-    throw Error(suggestions, "flake '%s' does not provide attribute %s",
-        flakeRef, showAttrPaths(getActualAttrPaths()));
 }
 
 std::vector<InstallableValue::DerivationInfo> InstallableFlake::toDerivations()
@@ -634,33 +635,10 @@ std::vector<InstallableValue::DerivationInfo> InstallableFlake::toDerivations()
 
 std::pair<Value *, Pos> InstallableFlake::toValue(EvalState & state)
 {
-    auto lockedFlake = getLockedFlake();
+    return {&getCursor(state)->forceValue(), noPos};
-
-    auto vOutputs = getFlakeOutputs(state, *lockedFlake);
-
-    auto emptyArgs = state.allocBindings(0);
-
-    Suggestions suggestions;
-
-    for (auto & attrPath : getActualAttrPaths()) {
-        try {
-            auto [v, pos] = findAlongAttrPath(state, attrPath, *emptyArgs, *vOutputs);
-            state.forceValue(*v, pos);
-            return {v, pos};
-        } catch (AttrPathNotFound & e) {
-            suggestions += e.info().suggestions;
-        }
 }
 
-    throw Error(
+std::vector<ref<eval_cache::AttrCursor>>
-        suggestions,
-        "flake '%s' does not provide attribute %s",
-        flakeRef,
-        showAttrPaths(getActualAttrPaths())
-    );
-}
-
-std::vector<std::pair<std::shared_ptr<eval_cache::AttrCursor>, std::string>>
 InstallableFlake::getCursors(EvalState & state)
 {
     auto evalCache = openEvalCache(state,
@@ -668,21 +646,55 @@ InstallableFlake::getCursors(EvalState & state)
 
     auto root = evalCache->getRoot();
 
-    std::vector<std::pair<std::shared_ptr<eval_cache::AttrCursor>, std::string>> res;
+    std::vector<ref<eval_cache::AttrCursor>> res;
 
     for (auto & attrPath : getActualAttrPaths()) {
         auto attr = root->findAlongAttrPath(parseAttrPath(state, attrPath));
-        if (attr) res.push_back({*attr, attrPath});
+        if (attr) res.push_back(ref(*attr));
     }
 
     return res;
 }
 
+ref<eval_cache::AttrCursor> InstallableFlake::getCursor(EvalState & state)
+{
+    auto lockedFlake = getLockedFlake();
+
+    auto cache = openEvalCache(state, lockedFlake);
+    auto root = cache->getRoot();
+
+    Suggestions suggestions;
+
+    auto attrPaths = getActualAttrPaths();
+
+    for (auto & attrPath : attrPaths) {
+        debug("trying flake output attribute '%s'", attrPath);
+
+        auto attrOrSuggestions = root->findAlongAttrPath(
+            parseAttrPath(state, attrPath),
+            true
+        );
+
+        if (!attrOrSuggestions) {
+            suggestions += attrOrSuggestions.getSuggestions();
+            continue;
+        }
+
+        return *attrOrSuggestions;
+    }
+
+    throw Error(
+        suggestions,
+        "flake '%s' does not provide attribute %s",
+        flakeRef,
+        showAttrPaths(attrPaths));
+}
+
 std::shared_ptr<flake::LockedFlake> InstallableFlake::getLockedFlake() const
 {
+    if (!_lockedFlake) {
         flake::LockFlags lockFlagsApplyConfig = lockFlags;
         lockFlagsApplyConfig.applyNixConfig = true;
-    if (!_lockedFlake) {
         _lockedFlake = std::make_shared<flake::LockedFlake>(lockFlake(*state, flakeRef, lockFlagsApplyConfig));
     }
     return _lockedFlake;
@@ -707,6 +719,10 @@ std::vector<std::shared_ptr<Installable>> SourceExprCommand::parseInstallables(
 {
     std::vector<std::shared_ptr<Installable>> result;
 
+    if (readOnlyMode) {
+        settings.readOnlyMode = true;
+    }
+
     if (file || expr) {
         if (file && expr)
             throw UsageError("'--file' and '--expr' are exclusive");
@@ -988,7 +1004,7 @@ InstallablesCommand::InstallablesCommand()
 void InstallablesCommand::prepare()
 {
     if (_installables.empty() && useDefaultInstallables())
-        // FIXME: commands like "nix install" should not have a
+        // FIXME: commands like "nix profile install" should not have a
         // default, probably.
         _installables.push_back(".");
     installables = parseInstallables(getStore(), _installables);
@@ -998,13 +1014,14 @@ std::optional<FlakeRef> InstallablesCommand::getFlakeRefForCompletion()
 {
     if (_installables.empty()) {
         if (useDefaultInstallables())
-            return parseFlakeRef(".", absPath("."));
+            return parseFlakeRefWithFragment(".", absPath(".")).first;
         return {};
     }
-    return parseFlakeRef(_installables.front(), absPath("."));
+    return parseFlakeRefWithFragment(_installables.front(), absPath(".")).first;
 }
 
-InstallableCommand::InstallableCommand()
+InstallableCommand::InstallableCommand(bool supportReadOnlyMode)
+    : SourceExprCommand(supportReadOnlyMode)
 {
     expectArgs({
         .label = "installable",

src/libcmd/installables.hh

@@ -80,10 +80,10 @@ struct Installable
         return {};
     }
 
-    virtual std::vector<std::pair<std::shared_ptr<eval_cache::AttrCursor>, std::string>>
+    virtual std::vector<ref<eval_cache::AttrCursor>>
     getCursors(EvalState & state);
 
-    std::pair<std::shared_ptr<eval_cache::AttrCursor>, std::string>
+    virtual ref<eval_cache::AttrCursor>
     getCursor(EvalState & state);
 
     virtual FlakeRef nixpkgsFlakeRef() const
@@ -180,9 +180,15 @@ struct InstallableFlake : InstallableValue
 
     std::pair<Value *, Pos> toValue(EvalState & state) override;
 
-    std::vector<std::pair<std::shared_ptr<eval_cache::AttrCursor>, std::string>>
+    /* Get a cursor to every attrpath in getActualAttrPaths() that
+       exists. */
+    std::vector<ref<eval_cache::AttrCursor>>
     getCursors(EvalState & state) override;
 
+    /* Get a cursor to the first attrpath in getActualAttrPaths() that
+       exists, or throw an exception with suggestions if none exists. */
+    ref<eval_cache::AttrCursor> getCursor(EvalState & state) override;
+
     std::shared_ptr<flake::LockedFlake> getLockedFlake() const;
 
     FlakeRef nixpkgsFlakeRef() const override;

src/libexpr/eval-cache.cc

@@ -306,9 +306,9 @@ Value * EvalCache::getRootValue()
     return *value;
 }
 
-std::shared_ptr<AttrCursor> EvalCache::getRoot()
+ref<AttrCursor> EvalCache::getRoot()
 {
-    return std::make_shared<AttrCursor>(ref(shared_from_this()), std::nullopt);
+    return make_ref<AttrCursor>(ref(shared_from_this()), std::nullopt);
 }
 
 AttrCursor::AttrCursor(

src/libexpr/eval-cache.hh

@@ -33,7 +33,7 @@ public:
         EvalState & state,
         RootLoader rootLoader);
 
-    std::shared_ptr<AttrCursor> getRoot();
+    ref<AttrCursor> getRoot();
 };
 
 enum AttrType {
@@ -104,6 +104,8 @@ public:
 
     ref<AttrCursor> getAttr(std::string_view name);
 
+    /* Get an attribute along a chain of attrsets. Note that this does
+       not auto-call functors or functions. */
     OrSuggestions<ref<AttrCursor>> findAlongAttrPath(const std::vector<Symbol> & attrPath, bool force = false);
 
     std::string getString();

src/libfetchers/fetchers.cc

@@ -238,9 +238,18 @@ std::optional<std::string> Input::getRef() const
 
 std::optional<Hash> Input::getRev() const
 {
-    if (auto s = maybeGetStrAttr(attrs, "rev"))
+    std::optional<Hash> hash = {};
-        return Hash::parseAny(*s, htSHA1);
+
-    return {};
+    if (auto s = maybeGetStrAttr(attrs, "rev")) {
+        try {
+            hash = Hash::parseAnyPrefixed(*s);
+        } catch (BadHash &e) {
+            // Default to sha1 for backwards compatibility with existing flakes
+            hash = Hash::parseAny(*s, htSHA1);
+        }
+    }
+
+    return hash;
 }
 
 std::optional<uint64_t> Input::getRevCount() const

src/libfetchers/git.cc

@@ -28,9 +28,7 @@ static std::string readHead(const Path & path)
 
 static bool isNotDotGitDirectory(const Path & path)
 {
-    static const std::regex gitDirRegex("^(?:.*/)?\\.git$");
+    return baseNameOf(path) != ".git";
-
-    return not std::regex_match(path, gitDirRegex);
 }
 
 struct GitInputScheme : InputScheme
@@ -189,8 +187,16 @@ struct GitInputScheme : InputScheme
         if (submodules) cacheType += "-submodules";
         if (allRefs) cacheType += "-all-refs";
 
+        auto checkHashType = [&](const std::optional<Hash> & hash)
+        {
+            if (hash.has_value() && !(hash->type == htSHA1 || hash->type == htSHA256))
+                throw Error("Hash '%s' is not supported by Git. Supported types are sha1 and sha256.", hash->to_string(Base16, true));
+        };
+
         auto getLockedAttrs = [&]()
         {
+            checkHashType(input.getRev());
+
             return Attrs({
                 {"type", cacheType},
                 {"name", name},

src/libfetchers/mercurial.cc

@@ -178,9 +178,11 @@ struct MercurialInputScheme : InputScheme
                 auto files = tokenizeString<std::set<std::string>>(
                     runHg({ "status", "-R", actualUrl, "--clean", "--modified", "--added", "--no-status", "--print0" }), "\0"s);
 
+                Path actualPath(absPath(actualUrl));
+
                 PathFilter filter = [&](const Path & p) -> bool {
-                    assert(hasPrefix(p, actualUrl));
+                    assert(hasPrefix(p, actualPath));
-                    std::string file(p, actualUrl.size() + 1);
+                    std::string file(p, actualPath.size() + 1);
 
                     auto st = lstat(p);
 
@@ -193,7 +195,7 @@ struct MercurialInputScheme : InputScheme
                     return files.count(file);
                 };
 
-                auto storePath = store->addToStore(input.getName(), actualUrl, FileIngestionMethod::Recursive, htSHA256, filter);
+                auto storePath = store->addToStore(input.getName(), actualPath, FileIngestionMethod::Recursive, htSHA256, filter);
 
                 return {std::move(storePath), input};
             }
@@ -201,8 +203,17 @@ struct MercurialInputScheme : InputScheme
 
         if (!input.getRef()) input.attrs.insert_or_assign("ref", "default");
 
+        auto checkHashType = [&](const std::optional<Hash> & hash)
+        {
+            if (hash.has_value() && hash->type != htSHA1)
+                throw Error("Hash '%s' is not supported by Mercurial. Only sha1 is supported.", hash->to_string(Base16, true));
+        };
+
+
         auto getLockedAttrs = [&]()
         {
+            checkHashType(input.getRev());
+
             return Attrs({
                 {"type", "hg"},
                 {"name", name},

src/libstore/build-result.hh

@@ -31,6 +31,8 @@ struct BuildResult
         ResolvesToAlreadyValid,
         NoSubstituters,
     } status = MiscFailure;
+
+    // FIXME: include entire ErrorInfo object.
     std::string errorMsg;
 
     std::string toString() const {

src/libstore/build/derivation-goal.cc

@@ -1371,8 +1371,7 @@ void DerivationGoal::done(
 {
     buildResult.status = status;
     if (ex)
-        // FIXME: strip: "error: "
+        buildResult.errorMsg = fmt("%s", normaltxt(ex->info().msg));
-        buildResult.errorMsg = ex->what();
     if (buildResult.status == BuildResult::TimedOut)
         worker.timedOut = true;
     if (buildResult.status == BuildResult::PermanentFailure)

src/libstore/build/local-derivation-goal.cc

@@ -704,6 +704,9 @@ void LocalDerivationGoal::startBuilder()
 
     /* Run the builder. */
     printMsg(lvlChatty, "executing builder '%1%'", drv->builder);
+    printMsg(lvlChatty, "using builder args '%1%'", concatStringsSep(" ", drv->args));
+    for (auto & i : drv->env)
+        printMsg(lvlVomit, "setting builder env variable '%1%'='%2%'", i.first, i.second);
 
     /* Create the log file. */
     Path logFile = openLogFile();

src/libstore/filetransfer.hh

@@ -31,7 +31,7 @@ struct FileTransferSettings : Config
         R"(
           The timeout (in seconds) for establishing connections in the
           binary cache substituter. It corresponds to `curl`’s
-          `--connect-timeout` option.
+          `--connect-timeout` option. A value of 0 means no limit.
         )"};
 
     Setting<unsigned long> stalledDownloadTimeout{
@@ -123,8 +123,6 @@ public:
 
     template<typename... Args>
     FileTransferError(FileTransfer::Error error, std::optional<std::string> response, const Args & ... args);
-
-    virtual const char* sname() const override { return "FileTransferError"; }
 };
 
 bool isUri(std::string_view s);

src/libstore/sqlite.cc

@@ -215,7 +215,6 @@ void handleSQLiteBusy(const SQLiteBusy & e)
     if (now > lastWarned + 10) {
         lastWarned = now;
         logWarning({
-            .name = "Sqlite busy",
             .msg = hintfmt(e.what())
         });
     }

src/libutil/args.cc

@@ -127,9 +127,9 @@ bool Args::processFlag(Strings::iterator & pos, Strings::iterator end)
                 if (flag.handler.arity == ArityAny) break;
                 throw UsageError("flag '%s' requires %d argument(s)", name, flag.handler.arity);
             }
-            if (flag.completer)
             if (auto prefix = needsCompletion(*pos)) {
                 anyCompleted = true;
+                if (flag.completer)
                     flag.completer(n, *prefix);
             }
             args.push_back(*pos++);
@@ -146,6 +146,7 @@ bool Args::processFlag(Strings::iterator & pos, Strings::iterator end)
                     && hasPrefix(name, std::string(*prefix, 2)))
                     completions->add("--" + name, flag->description);
             }
+            return false;
         }
         auto i = longFlags.find(std::string(*pos, 2));
         if (i == longFlags.end()) return false;
@@ -187,10 +188,12 @@ bool Args::processArgs(const Strings & args, bool finish)
     {
         std::vector<std::string> ss;
         for (const auto &[n, s] : enumerate(args)) {
-            ss.push_back(s);
+            if (auto prefix = needsCompletion(s)) {
+                ss.push_back(*prefix);
                 if (exp.completer)
-                if (auto prefix = needsCompletion(s))
                     exp.completer(n, *prefix);
+            } else
+                ss.push_back(s);
         }
         exp.handler.fun(ss);
         expectedArgs.pop_front();
@@ -279,21 +282,22 @@ static void _completePath(std::string_view prefix, bool onlyDirs)
 {
     completionType = ctFilenames;
     glob_t globbuf;
-    int flags = GLOB_NOESCAPE | GLOB_TILDE;
+    int flags = GLOB_NOESCAPE;
     #ifdef GLOB_ONLYDIR
     if (onlyDirs)
         flags |= GLOB_ONLYDIR;
     #endif
-    if (glob((std::string(prefix) + "*").c_str(), flags, nullptr, &globbuf) == 0) {
+    // using expandTilde here instead of GLOB_TILDE(_CHECK) so that ~<Tab> expands to /home/user/
+    if (glob((expandTilde(prefix) + "*").c_str(), flags, nullptr, &globbuf) == 0) {
         for (size_t i = 0; i < globbuf.gl_pathc; ++i) {
             if (onlyDirs) {
-                auto st = lstat(globbuf.gl_pathv[i]);
+                auto st = stat(globbuf.gl_pathv[i]);
                 if (!S_ISDIR(st.st_mode)) continue;
             }
             completions->add(globbuf.gl_pathv[i]);
         }
-        globfree(&globbuf);
     }
+    globfree(&globbuf);
 }
 
 void completePath(size_t, std::string_view prefix)
@@ -322,11 +326,6 @@ MultiCommand::MultiCommand(const Commands & commands_)
         .optional = true,
         .handler = {[=](std::string s) {
             assert(!command);
-            if (auto prefix = needsCompletion(s)) {
-                for (auto & [name, command] : commands)
-                    if (hasPrefix(name, *prefix))
-                        completions->add(name);
-            }
             auto i = commands.find(s);
             if (i == commands.end()) {
                 std::set<std::string> commandNames;
@@ -337,6 +336,11 @@ MultiCommand::MultiCommand(const Commands & commands_)
             }
             command = {s, i->second()};
             command->second->parent = this;
+        }},
+        .completer = {[&](size_t, std::string_view prefix) {
+            for (auto & [name, command] : commands)
+                if (hasPrefix(name, prefix))
+                    completions->add(name);
         }}
     });
 

src/libutil/error.cc

@@ -21,12 +21,9 @@ const std::string & BaseError::calcWhat() const
     if (what_.has_value())
         return *what_;
     else {
-        err.name = sname();
-
         std::ostringstream oss;
         showErrorInfo(oss, err, loggerSettings.showTrace);
         what_ = oss.str();
-
         return *what_;
     }
 }

src/libutil/error.hh

@@ -109,7 +109,6 @@ struct Trace {
 
 struct ErrorInfo {
     Verbosity level;
-    std::string name; // FIXME: rename
     hintformat msg;
     std::optional<ErrPos> errPos;
     std::list<Trace> traces;
@@ -162,8 +161,6 @@ public:
         : err(e)
     { }
 
-    virtual const char* sname() const { return "BaseError"; }
-
 #ifdef EXCEPTION_NEEDS_THROW_SPEC
     ~BaseError() throw () { };
     const char * what() const throw () { return calcWhat().c_str(); }
@@ -190,7 +187,6 @@ public:
     {                                                   \
     public:                                             \
         using superClass::superClass;                   \
-        virtual const char* sname() const override { return #newClass; } \
     }
 
 MakeError(Error, BaseError);
@@ -210,8 +206,6 @@ public:
         auto hf = hintfmt(args...);
         err.msg = hintfmt("%1%: %2%", normaltxt(hf.str()), strerror(errNo));
     }
-
-    virtual const char* sname() const override { return "SysError"; }
 };
 
 }

src/libutil/experimental-features.hh

@@ -50,10 +50,6 @@ public:
     ExperimentalFeature missingFeature;
 
     MissingExperimentalFeature(ExperimentalFeature);
-    virtual const char * sname() const override
-    {
-        return "MissingExperimentalFeature";
-    }
 };
 
 }

src/libutil/hash.cc

@@ -155,7 +155,7 @@ static std::pair<std::optional<HashType>, bool> getParsedTypeAndSRI(std::string_
 {
     bool isSRI = false;
 
-    // Parse the has type before the separater, if there was one.
+    // Parse the hash type before the separator, if there was one.
     std::optional<HashType> optParsedType;
     {
         auto hashRaw = splitPrefixTo(rest, ':');

src/libutil/hash.hh

@@ -93,13 +93,11 @@ public:
 
     std::string gitRev() const
     {
-        assert(type == htSHA1);
         return to_string(Base16, false);
     }
 
     std::string gitShortRev() const
     {
-        assert(type == htSHA1);
         return std::string(to_string(Base16, false), 0, 7);
     }
 

src/libutil/serialise.cc

@@ -357,7 +357,7 @@ Sink & operator << (Sink & sink, const Error & ex)
     sink
         << "Error"
         << info.level
-        << info.name
+        << "Error" // removed
         << info.msg.str()
         << 0 // FIXME: info.errPos
         << info.traces.size();
@@ -426,11 +426,10 @@ Error readError(Source & source)
     auto type = readString(source);
     assert(type == "Error");
     auto level = (Verbosity) readInt(source);
-    auto name = readString(source);
+    auto name = readString(source); // removed
     auto msg = readString(source);
     ErrorInfo info {
         .level = level,
-        .name = name,
         .msg = hintformat(std::move(format("%s") % msg)),
     };
     auto havePos = readNum<size_t>(source);

src/libutil/tests/url.cc

@@ -178,7 +178,7 @@ namespace nix {
     }
 
     TEST(parseURL, parseFileURLWithQueryAndFragment) {
-        auto s = "file:///none/of/your/business";
+        auto s = "file:///none/of//your/business";
         auto parsed = parseURL(s);
 
         ParsedURL expected {
@@ -186,7 +186,7 @@ namespace nix {
             .base = "",
             .scheme = "file",
             .authority = "",
-            .path = "/none/of/your/business",
+            .path = "/none/of//your/business",
             .query = (StringMap) { },
             .fragment = "",
         };

src/libutil/url-parts.hh

@@ -18,7 +18,7 @@ const static std::string userRegex = "(?:(?:" + unreservedRegex + "|" + pctEncod
 const static std::string authorityRegex = "(?:" + userRegex + "@)?" + hostRegex + "(?::[0-9]+)?";
 const static std::string pcharRegex = "(?:" + unreservedRegex + "|" + pctEncoded + "|" + subdelimsRegex + "|[:@])";
 const static std::string queryRegex = "(?:" + pcharRegex + "|[/? \"])*";
-const static std::string segmentRegex = "(?:" + pcharRegex + "+)";
+const static std::string segmentRegex = "(?:" + pcharRegex + "*)";
 const static std::string absPathRegex = "(?:(?:/" + segmentRegex + ")*/?)";
 const static std::string pathRegex = "(?:" + segmentRegex + "(?:/" + segmentRegex + ")*/?)";
 

src/libutil/util.cc

@@ -198,6 +198,17 @@ std::string_view baseNameOf(std::string_view path)
 }
 
 
+std::string expandTilde(std::string_view path)
+{
+    // TODO: expand ~user ?
+    auto tilde = path.substr(0, 2);
+    if (tilde == "~/" || tilde == "~")
+        return getHome() + std::string(path.substr(1));
+    else
+        return std::string(path);
+}
+
+
 bool isInDir(std::string_view path, std::string_view dir)
 {
     return path.substr(0, 1) == "/"
@@ -213,6 +224,15 @@ bool isDirOrInDir(std::string_view path, std::string_view dir)
 }
 
 
+struct stat stat(const Path & path)
+{
+    struct stat st;
+    if (stat(path.c_str(), &st))
+        throw SysError("getting status of '%1%'", path);
+    return st;
+}
+
+
 struct stat lstat(const Path & path)
 {
     struct stat st;

src/libutil/util.hh

@@ -68,6 +68,9 @@ Path dirOf(const PathView path);
    following the final `/' (trailing slashes are removed). */
 std::string_view baseNameOf(std::string_view path);
 
+/* Perform tilde expansion on a path. */
+std::string expandTilde(std::string_view path);
+
 /* Check whether 'path' is a descendant of 'dir'. Both paths must be
    canonicalized. */
 bool isInDir(std::string_view path, std::string_view dir);
@@ -77,6 +80,7 @@ bool isInDir(std::string_view path, std::string_view dir);
 bool isDirOrInDir(std::string_view path, std::string_view dir);
 
 /* Get status of `path'. */
+struct stat stat(const Path & path);
 struct stat lstat(const Path & path);
 
 /* Return true iff the given path exists. */

src/nix/app.cc

@@ -61,14 +61,18 @@ std::string resolveString(Store & store, const std::string & toResolve, const Bu
 
 UnresolvedApp Installable::toApp(EvalState & state)
 {
-    auto [cursor, attrPath] = getCursor(state);
+    auto cursor = getCursor(state);
+    auto attrPath = cursor->getAttrPath();
 
     auto type = cursor->getAttr("type")->getString();
 
+    std::string expected = !attrPath.empty() && attrPath[0] == "apps" ? "app" : "derivation";
+    if (type != expected)
+        throw Error("attribute '%s' should have type '%s'", cursor->getAttrPathStr(), expected);
+
     if (type == "app") {
         auto [program, context] = cursor->getAttr("program")->getStringWithContext();
 
-
         std::vector<StorePathWithOutputs> context2;
         for (auto & [path, name] : context)
             context2.push_back({path, {name}});
@@ -101,7 +105,7 @@ UnresolvedApp Installable::toApp(EvalState & state)
     }
 
     else
-        throw Error("attribute '%s' has unsupported type '%s'", attrPath, type);
+        throw Error("attribute '%s' has unsupported type '%s'", cursor->getAttrPathStr(), type);
 }
 
 // FIXME: move to libcmd

src/nix/eval.cc

@@ -16,7 +16,7 @@ struct CmdEval : MixJSON, InstallableCommand
     std::optional<std::string> apply;
     std::optional<Path> writeTo;
 
-    CmdEval()
+    CmdEval() : InstallableCommand(true /* supportReadOnlyMode */)
     {
         addFlag({
             .longName = "raw",

src/nix/flake.cc

@@ -705,7 +705,7 @@ struct CmdFlakeInitCommon : virtual Args, EvalCommand
             defaultTemplateAttrPathsPrefixes,
             lockFlags);
 
-        auto [cursor, attrPath] = installable.getCursor(*evalState);
+        auto cursor = installable.getCursor(*evalState);
 
         auto templateDirAttr = cursor->getAttr("path");
         auto templateDir = templateDirAttr->getString();

src/nix/flake.md

@@ -177,8 +177,8 @@ Currently the `type` attribute can be one of the following:
   attribute `url`.
 
   In URL form, the schema must be `http://`, `https://` or `file://`
-  URLs and the extension must be `.zip`, `.tar`, `.tar.gz`, `.tar.xz`,
+  URLs and the extension must be `.zip`, `.tar`, `.tgz`, `.tar.gz`,
-  `.tar.bz2` or `.tar.zst`.
+  `.tar.xz`, `.tar.bz2` or `.tar.zst`.
 
 * `github`: A more efficient way to fetch repositories from
   GitHub. The following attributes are required:

src/nix/search.cc

@@ -165,8 +165,8 @@ struct CmdSearch : InstallableCommand, MixJSON
             }
         };
 
-        for (auto & [cursor, prefix] : installable->getCursors(*state))
+        for (auto & cursor : installable->getCursors(*state))
-            visit(*cursor, parseAttrPath(*state, prefix), true);
+            visit(*cursor, cursor->getAttrPath(), true);
 
         if (!json && !results)
             throw Error("no results for the given search term(s)!");

tests/fetchMercurial.sh

@@ -7,7 +7,9 @@ fi
 
 clearStore
 
-repo=$TEST_ROOT/hg
+# Intentionally not in a canonical form
+# See https://github.com/NixOS/nix/issues/6195
+repo=$TEST_ROOT/./hg
 
 rm -rf $repo ${repo}-tmp $TEST_HOME/.cache/nix
 
@@ -28,6 +30,12 @@ echo world > $repo/hello
 hg commit --cwd $repo -m 'Bla2'
 rev2=$(hg log --cwd $repo -r tip --template '{node}')
 
+# Fetch an unclean branch.
+echo unclean > $repo/hello
+path=$(nix eval --impure --raw --expr "(builtins.fetchMercurial file://$repo).outPath")
+[[ $(cat $path/hello) = unclean ]]
+hg revert --cwd $repo --all
+
 # Fetch the default branch.
 path=$(nix eval --impure --raw --expr "(builtins.fetchMercurial file://$repo).outPath")
 [[ $(cat $path/hello) = world ]]

tests/flakes-run.sh

@@ -0,0 +1,29 @@
+source common.sh
+
+clearStore
+rm -rf $TEST_HOME/.cache $TEST_HOME/.config $TEST_HOME/.local
+cp ./shell-hello.nix ./config.nix $TEST_HOME
+cd $TEST_HOME
+
+cat <<EOF > flake.nix
+{
+    outputs = {self}: {
+      packages.$system.pkgAsPkg = (import ./shell-hello.nix).hello;
+      packages.$system.appAsApp = self.packages.$system.appAsApp;
+
+      apps.$system.pkgAsApp = self.packages.$system.pkgAsPkg;
+      apps.$system.appAsApp = {
+        type = "app";
+        program = "\${(import ./shell-hello.nix).hello}/bin/hello";
+      };
+    };
+}
+EOF
+nix run --no-write-lock-file .#appAsApp
+nix run --no-write-lock-file .#pkgAsPkg
+
+! nix run --no-write-lock-file .#pkgAsApp || fail "'nix run' shouldn’t accept an 'app' defined under 'packages'"
+! nix run --no-write-lock-file .#appAsPkg || fail "elements of 'apps' should be of type 'app'"
+
+clearStore
+

tests/local.mk

@@ -1,5 +1,6 @@
 nix_tests = \
   flakes.sh \
+  flakes-run.sh \
   ca/gc.sh \
   gc.sh \
   remote-store.sh \