Remove dependent realisations

This progress on #11896. It introduces some issues temporarily which
will be fixed when #11928 is fixed.

src/libstore-test-support/include/nix/store/tests/protocol.hh

@@ -88,16 +88,22 @@ public:
     }
 };
 
-#define VERSIONED_CHARACTERIZATION_TEST_NO_JSON(FIXTURE, NAME, STEM, VERSION, VALUE) \
+#define VERSIONED_READ_CHARACTERIZATION_TEST_NO_JSON(FIXTURE, NAME, STEM, VERSION, VALUE) \
-    TEST_F(FIXTURE, NAME##_read)                                                     \
+    TEST_F(FIXTURE, NAME##_read)                                                          \
-    {                                                                                \
+    {                                                                                     \
-        readProtoTest(STEM, VERSION, VALUE);                                         \
+        readProtoTest(STEM, VERSION, VALUE);                                              \
-    }                                                                                \
-    TEST_F(FIXTURE, NAME##_write)                                                    \
-    {                                                                                \
-        writeProtoTest(STEM, VERSION, VALUE);                                        \
     }
 
+#define VERSIONED_WRITE_CHARACTERIZATION_TEST_NO_JSON(FIXTURE, NAME, STEM, VERSION, VALUE) \
+    TEST_F(FIXTURE, NAME##_write)                                                          \
+    {                                                                                      \
+        writeProtoTest(STEM, VERSION, VALUE);                                              \
+    }
+
+#define VERSIONED_CHARACTERIZATION_TEST_NO_JSON(FIXTURE, NAME, STEM, VERSION, VALUE)  \
+    VERSIONED_READ_CHARACTERIZATION_TEST_NO_JSON(FIXTURE, NAME, STEM, VERSION, VALUE) \
+    VERSIONED_WRITE_CHARACTERIZATION_TEST_NO_JSON(FIXTURE, NAME, STEM, VERSION, VALUE)
+
 #define VERSIONED_CHARACTERIZATION_TEST(FIXTURE, NAME, STEM, VERSION, VALUE)     \
     VERSIONED_CHARACTERIZATION_TEST_NO_JSON(FIXTURE, NAME, STEM, VERSION, VALUE) \
     TEST_F(FIXTURE, NAME##_json_read)                                            \

src/libstore-tests/common-protocol.cc

@@ -47,24 +47,30 @@ public:
     }
 };
 
-#define CHARACTERIZATION_TEST(NAME, STEM, VALUE) \
+#define READ_CHARACTERIZATION_TEST(NAME, STEM, VALUE) \
-    TEST_F(CommonProtoTest, NAME##_read)         \
+    TEST_F(CommonProtoTest, NAME##_read)              \
-    {                                            \
+    {                                                 \
-        readProtoTest(STEM, VALUE);              \
+        readProtoTest(STEM, VALUE);                   \
-    }                                            \
+    }                                                 \
-    TEST_F(CommonProtoTest, NAME##_write)        \
+    TEST_F(CommonProtoTest, NAME##_json_read)         \
-    {                                            \
+    {                                                 \
-        writeProtoTest(STEM, VALUE);             \
+        readJsonTest(STEM, VALUE);                    \
-    }                                            \
-    TEST_F(CommonProtoTest, NAME##_json_read)    \
-    {                                            \
-        readJsonTest(STEM, VALUE);               \
-    }                                            \
-    TEST_F(CommonProtoTest, NAME##_json_write)   \
-    {                                            \
-        writeJsonTest(STEM, VALUE);              \
     }
 
+#define WRITE_CHARACTERIZATION_TEST(NAME, STEM, VALUE) \
+    TEST_F(CommonProtoTest, NAME##_write)              \
+    {                                                  \
+        writeProtoTest(STEM, VALUE);                   \
+    }                                                  \
+    TEST_F(CommonProtoTest, NAME##_json_write)         \
+    {                                                  \
+        writeJsonTest(STEM, VALUE);                    \
+    }
+
+#define CHARACTERIZATION_TEST(NAME, STEM, VALUE)  \
+    READ_CHARACTERIZATION_TEST(NAME, STEM, VALUE) \
+    WRITE_CHARACTERIZATION_TEST(NAME, STEM, VALUE)
+
 CHARACTERIZATION_TEST(
     string,
     "string",
@@ -141,7 +147,7 @@ CHARACTERIZATION_TEST(
         },
     }))
 
-CHARACTERIZATION_TEST(
+READ_CHARACTERIZATION_TEST(
     realisation_with_deps,
     "realisation-with-deps",
     (std::tuple<Realisation>{
@@ -149,16 +155,6 @@ CHARACTERIZATION_TEST(
             {
                 .outPath = StorePath{"g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo"},
                 .signatures = {"asdf", "qwer"},
-                .dependentRealisations =
-                    {
-                        {
-                            DrvOutput{
-                                .drvHash = Hash::parseSRI("sha256-b4afnqKCO9oWXgYHb9DeQ2berSwOjS27rSd9TxXDc/U="),
-                                .outputName = "quux",
-                            },
-                            StorePath{"g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo"},
-                        },
-                    },
             },
             {
                 .drvHash = Hash::parseSRI("sha256-FePFYIlMuycIXPZbWi7LGEiMmZSX9FMbaQenWBzm1Sc="),

src/libstore-tests/realisation.cc

@@ -44,54 +44,45 @@ TEST_P(RealisationJsonTest, to_json)
     writeJsonTest(name, value);
 }
 
+Realisation simple{
+    {
+        .outPath = StorePath{"g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo.drv"},
+    },
+    {
+        .drvHash = Hash::parseExplicitFormatUnprefixed(
+            "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad",
+            HashAlgorithm::SHA256,
+            HashFormat::Base16),
+        .outputName = "foo",
+    },
+};
+
 INSTANTIATE_TEST_SUITE_P(
     RealisationJSON,
     RealisationJsonTest,
-    ([] {
+    ::testing::Values(
-        Realisation simple{
+        std::pair{
-            {
+            "simple",
-                .outPath = StorePath{"g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo.drv"},
+            simple,
-            },
+        },
-            {
+        std::pair{
-                .drvHash = Hash::parseExplicitFormatUnprefixed(
+            "with-signature",
-                    "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad",
+            [&] {
-                    HashAlgorithm::SHA256,
+                auto r = simple;
-                    HashFormat::Base16),
+                // FIXME actually sign properly
-                .outputName = "foo",
+                r.signatures = {"asdfasdfasdf"};
-            },
+                return r;
-        };
+            }(),
-        return ::testing::Values(
+        }));
-            std::pair{
-                "simple",
-                simple,
-            },
-            std::pair{
-                "with-signature",
-                [&] {
-                    auto r = simple;
-                    // FIXME actually sign properly
-                    r.signatures = {"asdfasdfasdf"};
-                    return r;
-                }()},
-            std::pair{
-                "with-dependent-realisations",
-                [&] {
-                    auto r = simple;
-                    r.dependentRealisations = {{
-                        {
-                            .drvHash = Hash::parseExplicitFormatUnprefixed(
-                                "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad",
-                                HashAlgorithm::SHA256,
-                                HashFormat::Base16),
-                            .outputName = "foo",
-                        },
-                        StorePath{"g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo.drv"},
-                    }};
-                    return r;
-                }(),
-            });
-    }
 
-     ()));
+/**
+ * We no longer have a notion of "dependent realisations", but we still
+ * want to parse old realisation files. So make this just be a read test
+ * (no write direction), accordingly.
+ */
+TEST_F(RealisationTest, dependent_realisations_from_json)
+{
+    readJsonTest("with-dependent-realisations", simple);
+}
 
 } // namespace nix

src/libstore-tests/serve-protocol.cc

@@ -116,7 +116,7 @@ VERSIONED_CHARACTERIZATION_TEST(
         },
     }))
 
-VERSIONED_CHARACTERIZATION_TEST(
+VERSIONED_READ_CHARACTERIZATION_TEST(
     ServeProtoTest,
     realisation_with_deps,
     "realisation-with-deps",
@@ -126,16 +126,6 @@ VERSIONED_CHARACTERIZATION_TEST(
             {
                 .outPath = StorePath{"g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo"},
                 .signatures = {"asdf", "qwer"},
-                .dependentRealisations =
-                    {
-                        {
-                            DrvOutput{
-                                .drvHash = Hash::parseSRI("sha256-b4afnqKCO9oWXgYHb9DeQ2berSwOjS27rSd9TxXDc/U="),
-                                .outputName = "quux",
-                            },
-                            StorePath{"g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo"},
-                        },
-                    },
             },
             {
                 .drvHash = Hash::parseSRI("sha256-FePFYIlMuycIXPZbWi7LGEiMmZSX9FMbaQenWBzm1Sc="),

src/libstore-tests/worker-protocol.cc

@@ -169,7 +169,7 @@ VERSIONED_CHARACTERIZATION_TEST(
         },
     }))
 
-VERSIONED_CHARACTERIZATION_TEST(
+VERSIONED_READ_CHARACTERIZATION_TEST(
     WorkerProtoTest,
     realisation_with_deps,
     "realisation-with-deps",
@@ -179,16 +179,6 @@ VERSIONED_CHARACTERIZATION_TEST(
             {
                 .outPath = StorePath{"g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo"},
                 .signatures = {"asdf", "qwer"},
-                .dependentRealisations =
-                    {
-                        {
-                            DrvOutput{
-                                .drvHash = Hash::parseSRI("sha256-b4afnqKCO9oWXgYHb9DeQ2berSwOjS27rSd9TxXDc/U="),
-                                .outputName = "quux",
-                            },
-                            StorePath{"g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo"},
-                        },
-                    },
             },
             {
                 .drvHash = Hash::parseSRI("sha256-FePFYIlMuycIXPZbWi7LGEiMmZSX9FMbaQenWBzm1Sc="),

src/libstore/build/derivation-goal.cc

@@ -209,11 +209,6 @@ Goal::Co DerivationGoal::haveDerivation(bool storeDerivation)
                         .outputName = wantedOutput,
                     }};
                 newRealisation.signatures.clear();
-                if (!drv->type().isFixed()) {
-                    auto & drvStore = worker.evalStore.isValidPath(drvPath) ? worker.evalStore : worker.store;
-                    newRealisation.dependentRealisations =
-                        drvOutputReferences(worker.store, *drv, realisation.outPath, &drvStore);
-                }
                 worker.store.signRealisation(newRealisation);
                 worker.store.registerDrvOutput(newRealisation);
             }

src/libstore/build/drv-output-substitution-goal.cc

@@ -86,32 +86,8 @@ Goal::Co DrvOutputSubstitutionGoal::init()
         if (!outputInfo)
             continue;
 
-        bool failed = false;
-
         Goals waitees;
 
-        for (const auto & [depId, depPath] : outputInfo->dependentRealisations) {
-            if (depId != id) {
-                if (auto localOutputInfo = worker.store.queryRealisation(depId);
-                    localOutputInfo && localOutputInfo->outPath != depPath) {
-                    warn(
-                        "substituter '%s' has an incompatible realisation for '%s', ignoring.\n"
-                        "Local:  %s\n"
-                        "Remote: %s",
-                        sub->config.getHumanReadableURI(),
-                        depId.to_string(),
-                        worker.store.printStorePath(localOutputInfo->outPath),
-                        worker.store.printStorePath(depPath));
-                    failed = true;
-                    break;
-                }
-                waitees.insert(worker.makeDrvOutputSubstitutionGoal(depId));
-            }
-        }
-
-        if (failed)
-            continue;
-
         waitees.insert(worker.makePathSubstitutionGoal(outputInfo->outPath));
 
         co_await await(std::move(waitees));

src/libstore/ca-specific-schema.sql

@@ -12,30 +12,3 @@ create table if not exists Realisations (
 );
 
 create index if not exists IndexRealisations on Realisations(drvPath, outputName);
-
--- We can end-up in a weird edge-case where a path depends on itself because
--- it’s an output of a CA derivation, that happens to be the same as one of its
--- dependencies.
--- In that case we have a dependency loop (path -> realisation1 -> realisation2
--- -> path) that we need to break by removing the dependencies between the
--- realisations
-create trigger if not exists DeleteSelfRefsViaRealisations before delete on ValidPaths
-  begin
-    delete from RealisationsRefs where realisationReference in (
-      select id from Realisations where outputPath = old.id
-    );
-  end;
-
-create table if not exists RealisationsRefs (
-    referrer integer not null,
-    realisationReference integer,
-    foreign key (referrer) references Realisations(id) on delete cascade,
-    foreign key (realisationReference) references Realisations(id) on delete restrict
-);
--- used by deletion trigger
-create index if not exists IndexRealisationsRefsRealisationReference on RealisationsRefs(realisationReference);
-
--- used by QueryRealisationReferences
-create index if not exists IndexRealisationsRefs on RealisationsRefs(referrer);
--- used by cascade deletion when ValidPaths is deleted
-create index if not exists IndexRealisationsRefsOnOutputPath on Realisations(outputPath);

src/libstore/include/nix/store/realisation.hh

@@ -56,14 +56,6 @@ struct UnkeyedRealisation
 
     StringSet signatures;
 
-    /**
-     * The realisations that are required for the current one to be valid.
-     *
-     * When importing this realisation, the store will first check that all its
-     * dependencies exist, and map to the correct output path
-     */
-    std::map<DrvOutput, StorePath> dependentRealisations;
-
     std::string fingerprint(const DrvOutput & key) const;
 
     void sign(const DrvOutput & key, const Signer &);
@@ -87,10 +79,6 @@ struct Realisation : UnkeyedRealisation
 
     bool isCompatibleWith(const UnkeyedRealisation & other) const;
 
-    static std::set<Realisation> closure(Store &, const std::set<Realisation> &);
-
-    static void closure(Store &, const std::set<Realisation> &, std::set<Realisation> & res);
-
     bool operator==(const Realisation &) const = default;
     auto operator<=>(const Realisation &) const = default;
 };
@@ -154,10 +142,6 @@ struct RealisedPath
      */
     const StorePath & path() const &;
 
-    void closure(Store & store, Set & ret) const;
-    static void closure(Store & store, const Set & startPaths, Set & ret);
-    Set closure(Store & store) const;
-
     bool operator==(const RealisedPath &) const = default;
     auto operator<=>(const RealisedPath &) const = default;
 };

src/libstore/include/nix/store/store-api.hh

@@ -1001,9 +1001,6 @@ decodeValidPathInfo(const Store & store, std::istream & str, std::optional<HashR
 
 const ContentAddress * getDerivationCA(const BasicDerivation & drv);
 
-std::map<DrvOutput, StorePath>
-drvOutputReferences(Store & store, const Derivation & drv, const StorePath & outputPath, Store * evalStore = nullptr);
-
 template<>
 struct json_avoids_null<TrustedFlag> : std::true_type
 {};

src/libstore/local-store.cc

@@ -390,21 +390,6 @@ LocalStore::LocalStore(ref<const Config> config)
                     where drvPath = ?
                     ;
             )");
-        state->stmts->QueryRealisationReferences.create(
-            state->db,
-            R"(
-                select drvPath, outputName from Realisations
-                    join RealisationsRefs on realisationReference = Realisations.id
-                    where referrer = ?;
-            )");
-        state->stmts->AddRealisationReference.create(
-            state->db,
-            R"(
-                insert or replace into RealisationsRefs (referrer, realisationReference)
-                values (
-                    (select id from Realisations where drvPath = ? and outputName = ?),
-                    (select id from Realisations where drvPath = ? and outputName = ?));
-            )");
     }
 }
 
@@ -654,25 +639,6 @@ void LocalStore::registerDrvOutput(const Realisation & info)
                     concatStringsSep(" ", info.signatures))
                 .exec();
         }
-        for (auto & [outputId, depPath] : info.dependentRealisations) {
-            auto localRealisation = queryRealisationCore_(*state, outputId);
-            if (!localRealisation)
-                throw Error(
-                    "unable to register the derivation '%s' as it "
-                    "depends on the non existent '%s'",
-                    info.id.to_string(),
-                    outputId.to_string());
-            if (localRealisation->second.outPath != depPath)
-                throw Error(
-                    "unable to register the derivation '%s' as it "
-                    "depends on a realisation of '%s' that doesn’t"
-                    "match what we have locally",
-                    info.id.to_string(),
-                    outputId.to_string());
-            state->stmts->AddRealisationReference
-                .use()(info.id.strHash())(info.id.outputName)(outputId.strHash())(outputId.outputName)
-                .exec();
-        }
     });
 }
 
@@ -1609,21 +1575,6 @@ std::optional<const UnkeyedRealisation> LocalStore::queryRealisation_(LocalStore
         return std::nullopt;
     auto [realisationDbId, res] = *maybeCore;
 
-    std::map<DrvOutput, StorePath> dependentRealisations;
-    auto useRealisationRefs(state.stmts->QueryRealisationReferences.use()(realisationDbId));
-    while (useRealisationRefs.next()) {
-        auto depId = DrvOutput{
-            Hash::parseAnyPrefixed(useRealisationRefs.getStr(0)),
-            useRealisationRefs.getStr(1),
-        };
-        auto dependentRealisation = queryRealisationCore_(state, depId);
-        assert(dependentRealisation); // Enforced by the db schema
-        auto outputPath = dependentRealisation->second.outPath;
-        dependentRealisations.insert({depId, outputPath});
-    }
-
-    res.dependentRealisations = dependentRealisations;
-
     return {res};
 }
 

src/libstore/misc.cc

@@ -330,65 +330,6 @@ StorePaths Store::topoSortPaths(const StorePathSet & paths)
         }});
 }
 
-std::map<DrvOutput, StorePath>
-drvOutputReferences(const std::set<Realisation> & inputRealisations, const StorePathSet & pathReferences)
-{
-    std::map<DrvOutput, StorePath> res;
-
-    for (const auto & input : inputRealisations) {
-        if (pathReferences.count(input.outPath)) {
-            res.insert({input.id, input.outPath});
-        }
-    }
-
-    return res;
-}
-
-std::map<DrvOutput, StorePath>
-drvOutputReferences(Store & store, const Derivation & drv, const StorePath & outputPath, Store * evalStore_)
-{
-    auto & evalStore = evalStore_ ? *evalStore_ : store;
-
-    std::set<Realisation> inputRealisations;
-
-    auto accumRealisations = [&](this auto & self,
-                                 const StorePath & inputDrv,
-                                 const DerivedPathMap<StringSet>::ChildNode & inputNode) -> void {
-        if (!inputNode.value.empty()) {
-            auto outputHashes = staticOutputHashes(evalStore, evalStore.readDerivation(inputDrv));
-            for (const auto & outputName : inputNode.value) {
-                auto outputHash = get(outputHashes, outputName);
-                if (!outputHash)
-                    throw Error(
-                        "output '%s' of derivation '%s' isn't realised", outputName, store.printStorePath(inputDrv));
-                DrvOutput key{*outputHash, outputName};
-                auto thisRealisation = store.queryRealisation(key);
-                if (!thisRealisation)
-                    throw Error(
-                        "output '%s' of derivation '%s' isn’t built", outputName, store.printStorePath(inputDrv));
-                inputRealisations.insert({*thisRealisation, std::move(key)});
-            }
-        }
-        if (!inputNode.value.empty()) {
-            auto d = makeConstantStorePathRef(inputDrv);
-            for (const auto & [outputName, childNode] : inputNode.childMap) {
-                SingleDerivedPath next = SingleDerivedPath::Built{d, outputName};
-                self(
-                    // TODO deep resolutions for dynamic derivations, issue #8947, would go here.
-                    resolveDerivedPath(store, next, evalStore_),
-                    childNode);
-            }
-        }
-    };
-
-    for (const auto & [inputDrv, inputNode] : drv.inputDrvs.map)
-        accumRealisations(inputDrv, inputNode);
-
-    auto info = store.queryPathInfo(outputPath);
-
-    return drvOutputReferences(Realisation::closure(store, inputRealisations), info->references);
-}
-
 OutputPathMap resolveDerivedPath(Store & store, const DerivedPath::Built & bfd, Store * evalStore_)
 {
     auto drvPath = resolveDerivedPath(store, *bfd.drvPath, evalStore_);

src/libstore/realisation.cc

@@ -1,6 +1,5 @@
 #include "nix/store/realisation.hh"
 #include "nix/store/store-api.hh"
-#include "nix/util/closure.hh"
 #include "nix/util/signature/local-keys.hh"
 #include "nix/util/json-utils.hh"
 #include <nlohmann/json.hpp>
@@ -26,41 +25,6 @@ std::string DrvOutput::to_string() const
     return strHash() + "!" + outputName;
 }
 
-std::set<Realisation> Realisation::closure(Store & store, const std::set<Realisation> & startOutputs)
-{
-    std::set<Realisation> res;
-    Realisation::closure(store, startOutputs, res);
-    return res;
-}
-
-void Realisation::closure(Store & store, const std::set<Realisation> & startOutputs, std::set<Realisation> & res)
-{
-    auto getDeps = [&](const Realisation & current) -> std::set<Realisation> {
-        std::set<Realisation> res;
-        for (auto & [currentDep, _] : current.dependentRealisations) {
-            if (auto currentRealisation = store.queryRealisation(currentDep))
-                res.insert({*currentRealisation, currentDep});
-            else
-                throw Error("Unrealised derivation '%s'", currentDep.to_string());
-        }
-        return res;
-    };
-
-    computeClosure<Realisation>(
-        startOutputs,
-        res,
-        [&](const Realisation & current, std::function<void(std::promise<std::set<Realisation>> &)> processEdges) {
-            std::promise<std::set<Realisation>> promise;
-            try {
-                auto res = getDeps(current);
-                promise.set_value(res);
-            } catch (...) {
-                promise.set_exception(std::current_exception());
-            }
-            return processEdges(promise);
-        });
-}
-
 std::string UnkeyedRealisation::fingerprint(const DrvOutput & key) const
 {
     nlohmann::json serialized = Realisation{*this, key};
@@ -99,43 +63,7 @@ const StorePath & RealisedPath::path() const &
 
 bool Realisation::isCompatibleWith(const UnkeyedRealisation & other) const
 {
-    if (outPath == other.outPath) {
+    return outPath == other.outPath;
-        if (dependentRealisations.empty() != other.dependentRealisations.empty()) {
-            warn(
-                "Encountered a realisation for '%s' with an empty set of "
-                "dependencies. This is likely an artifact from an older Nix. "
-                "I’ll try to fix the realisation if I can",
-                id.to_string());
-            return true;
-        } else if (dependentRealisations == other.dependentRealisations) {
-            return true;
-        }
-    }
-    return false;
-}
-
-void RealisedPath::closure(Store & store, const RealisedPath::Set & startPaths, RealisedPath::Set & ret)
-{
-    // FIXME: This only builds the store-path closure, not the real realisation
-    // closure
-    StorePathSet initialStorePaths, pathsClosure;
-    for (auto & path : startPaths)
-        initialStorePaths.insert(path.path());
-    store.computeFSClosure(initialStorePaths, pathsClosure);
-    ret.insert(startPaths.begin(), startPaths.end());
-    ret.insert(pathsClosure.begin(), pathsClosure.end());
-}
-
-void RealisedPath::closure(Store & store, RealisedPath::Set & ret) const
-{
-    RealisedPath::closure(store, {*this}, ret);
-}
-
-RealisedPath::Set RealisedPath::closure(Store & store) const
-{
-    RealisedPath::Set ret;
-    closure(store, ret);
-    return ret;
 }
 
 } // namespace nix
@@ -162,27 +90,19 @@ UnkeyedRealisation adl_serializer<UnkeyedRealisation>::from_json(const json & js
     if (auto signaturesOpt = optionalValueAt(json, "signatures"))
         signatures = *signaturesOpt;
 
-    std::map<DrvOutput, StorePath> dependentRealisations;
-    if (auto jsonDependencies = optionalValueAt(json, "dependentRealisations"))
-        for (auto & [jsonDepId, jsonDepOutPath] : getObject(*jsonDependencies))
-            dependentRealisations.insert({DrvOutput::parse(jsonDepId), jsonDepOutPath});
-
     return UnkeyedRealisation{
         .outPath = valueAt(json, "outPath"),
         .signatures = signatures,
-        .dependentRealisations = dependentRealisations,
     };
 }
 
 void adl_serializer<UnkeyedRealisation>::to_json(json & json, const UnkeyedRealisation & r)
 {
-    auto jsonDependentRealisations = nlohmann::json::object();
-    for (auto & [depId, depOutPath] : r.dependentRealisations)
-        jsonDependentRealisations.emplace(depId.to_string(), depOutPath);
     json = {
         {"outPath", r.outPath},
         {"signatures", r.signatures},
-        {"dependentRealisations", jsonDependentRealisations},
+        // back-compat
+        {"dependentRealisations", json::object()},
     };
 }
 

src/libstore/restricted-store.cc

@@ -292,7 +292,7 @@ std::vector<KeyedBuildResult> RestrictedStore::buildPathsWithResults(
     next->computeFSClosure(newPaths, closure);
     for (auto & path : closure)
         goal.addDependency(path);
-    for (auto & real : Realisation::closure(*next, newRealisations))
+    for (auto & real : newRealisations)
         goal.addedDrvOutputs.insert(real.id);
 
     return results;

src/libstore/store-api.cc

@@ -915,36 +915,21 @@ std::map<StorePath, StorePath> copyPaths(
     SubstituteFlag substitute)
 {
     StorePathSet storePaths;
-    std::set<Realisation> toplevelRealisations;
+    std::vector<const Realisation *> realisations;
     for (auto & path : paths) {
         storePaths.insert(path.path());
         if (auto * realisation = std::get_if<Realisation>(&path.raw)) {
             experimentalFeatureSettings.require(Xp::CaDerivations);
-            toplevelRealisations.insert(*realisation);
+            realisations.push_back(realisation);
         }
     }
 
     auto pathsMap = copyPaths(srcStore, dstStore, storePaths, repair, checkSigs, substitute);
 
     try {
-        // Copy the realisation closure
+        // Copy the realisations. TODO batch this
-        processGraph<Realisation>(
+        for (const auto * realisation : realisations)
-            Realisation::closure(srcStore, toplevelRealisations),
+            dstStore.registerDrvOutput(*realisation, checkSigs);
-            [&](const Realisation & current) -> std::set<Realisation> {
-                std::set<Realisation> children;
-                for (const auto & [drvOutput, _] : current.dependentRealisations) {
-                    auto currentChild = srcStore.queryRealisation(drvOutput);
-                    if (!currentChild)
-                        throw Error(
-                            "incomplete realisation closure: '%s' is a "
-                            "dependency of '%s' but isn't registered",
-                            drvOutput.to_string(),
-                            current.id.to_string());
-                    children.insert({*currentChild, drvOutput});
-                }
-                return children;
-            },
-            [&](const Realisation & current) -> void { dstStore.registerDrvOutput(current, checkSigs); });
     } catch (MissingExperimentalFeature & e) {
         // Don't fail if the remote doesn't support CA derivations is it might
         // not be within our control to change that, and we might still want
@@ -1055,8 +1040,19 @@ void copyClosure(
     if (&srcStore == &dstStore)
         return;
 
-    RealisedPath::Set closure;
+    StorePathSet closure0;
-    RealisedPath::closure(srcStore, paths, closure);
+    for (auto & path : paths) {
+        if (auto * opaquePath = std::get_if<OpaquePath>(&path.raw)) {
+            closure0.insert(opaquePath->path);
+        }
+    }
+
+    StorePathSet closure1;
+    srcStore.computeFSClosure(closure0, closure1);
+
+    RealisedPath::Set closure = paths;
+    for (auto && path : closure1)
+        closure.insert({std::move(path)});
 
     copyPaths(srcStore, dstStore, closure, repair, checkSigs, substitute);
 }

tests/functional/ca/duplicate-realisation-in-closure.sh

@@ -25,4 +25,9 @@ nix build -f nondeterministic.nix dep2 --no-link
 # If everything goes right, we should rebuild dep2 rather than fetch it from
 # the cache (because that would mean duplicating `current-time` in the closure),
 # and have `dep1 == dep2`.
+
+# FIXME: Force the use of small-step resolutions only to fix this in a
+# better way (#11896, #11928).
+skipTest "temporarily broken because dependent realisations are removed"
+
 nix build --substituters "$REMOTE_STORE" -f nondeterministic.nix toplevel --no-require-sigs --no-link

tests/functional/ca/substitute.sh

@@ -22,7 +22,10 @@ nix copy --to "$REMOTE_STORE" --file ./content-addressed.nix
 
 # Restart the build on an empty store, ensuring that we don't build
 clearStore
-buildDrvs --substitute --substituters "$REMOTE_STORE" --no-require-sigs -j0 transitivelyDependentCA
+# FIXME: `dependentCA` should not need to be explicitly mentioned in
+# this. Force the use of small-step resolutions only to allow not
+# mentioning it explicitly again. (#11896, #11928).
+buildDrvs --substitute --substituters "$REMOTE_STORE" --no-require-sigs -j0 transitivelyDependentCA dependentCA
 # Check that the thing we’ve just substituted has its realisation stored
 nix realisation info --file ./content-addressed.nix transitivelyDependentCA
 # Check that its dependencies have it too