Lazy trees

doc/manual/generate-manpage.nix

@@ -2,7 +2,7 @@ let
   inherit (builtins)
     attrNames attrValues fromJSON listToAttrs mapAttrs
     concatStringsSep concatMap length lessThan replaceStrings sort;
-  inherit (import ./utils.nix) concatStrings optionalString filterAttrs trim squash unique showSettings;
+  inherit (import <nix/utils.nix>) concatStrings optionalString filterAttrs trim squash unique showSettings;
 in
 
 commandDump:

doc/manual/local.mk

@@ -32,7 +32,7 @@ dummy-env = env -i \
 	NIX_STATE_DIR=/dummy \
 	NIX_CONFIG='cores = 0'
 
-nix-eval = $(dummy-env) $(bindir)/nix eval --experimental-features nix-command -I nix/corepkgs=corepkgs --store dummy:// --impure --raw
+nix-eval = $(dummy-env) $(bindir)/nix eval --experimental-features nix-command -I nix=doc/manual --store dummy:// --impure --raw
 
 # re-implement mdBook's include directive to make it usable for terminal output and for proper @docroot@ substitution
 define process-includes

flake.nix

@@ -129,6 +129,7 @@
             bzip2 xz brotli editline
             openssl sqlite
             libarchive
+            libgit2
             boost
             lowdown-nix
           ]

src/libcmd/common-eval-args.cc

@@ -8,6 +8,8 @@
 #include "flake/flakeref.hh"
 #include "store-api.hh"
 #include "command.hh"
+#include "fs-input-accessor.hh"
+#include "tarball.hh"
 
 namespace nix {
 
@@ -165,15 +167,17 @@ SourcePath lookupFileArg(EvalState & state, std::string_view s)
 {
     if (EvalSettings::isPseudoUrl(s)) {
         auto storePath = fetchers::downloadTarball(
-            state.store, EvalSettings::resolvePseudoUrl(s), "source", false).tree.storePath;
-        return state.rootPath(CanonPath(state.store->toRealPath(storePath)));
+            state.store, EvalSettings::resolvePseudoUrl(s), "source", false).storePath;
+        auto accessor = makeStorePathAccessor(state.store, storePath);
+        state.registerAccessor(accessor);
+        return accessor->root();
     }
 
     else if (hasPrefix(s, "flake:")) {
         experimentalFeatureSettings.require(Xp::Flakes);
         auto flakeRef = parseFlakeRef(std::string(s.substr(6)), {}, true, false);
-        auto storePath = flakeRef.resolve(state.store).fetchTree(state.store).first.storePath;
-        return state.rootPath(CanonPath(state.store->toRealPath(storePath)));
+        auto [accessor, _] = flakeRef.resolve(state.store).lazyFetch(state.store);
+        return accessor->root();
     }
 
     else if (s.size() > 2 && s.at(0) == '<' && s.at(s.size() - 1) == '>') {

src/libcmd/installables.cc

@@ -19,6 +19,7 @@
 #include "url.hh"
 #include "registry.hh"
 #include "build-result.hh"
+#include "fs-input-accessor.hh"
 
 #include <regex>
 #include <queue>
@@ -108,7 +109,7 @@ MixFlakeOptions::MixFlakeOptions()
         .category = category,
         .labels = {"flake-lock-path"},
         .handler = {[&](std::string lockFilePath) {
-            lockFlags.referenceLockFilePath = lockFilePath;
+            lockFlags.referenceLockFilePath = getUnfilteredRootPath(CanonPath::fromCwd(lockFilePath));
         }},
         .completer = completePath
     });
@@ -119,7 +120,7 @@ MixFlakeOptions::MixFlakeOptions()
         .category = category,
         .labels = {"flake-lock-path"},
         .handler = {[&](std::string lockFilePath) {
-            lockFlags.outputLockFilePath = lockFilePath;
+            lockFlags.outputLockFilePath = getUnfilteredRootPath(CanonPath::fromCwd(lockFilePath));
         }},
         .completer = completePath
     });
@@ -233,9 +234,10 @@ void SourceExprCommand::completeInstallable(std::string_view prefix)
 
             evalSettings.pureEval = false;
             auto state = getEvalState();
-            Expr *e = state->parseExprFromFile(
-                resolveExprPath(state->checkSourcePath(lookupFileArg(*state, *file)))
-                );
+            auto e =
+                state->parseExprFromFile(
+                    resolveExprPath(
+                        lookupFileArg(*state, *file)));
 
             Value root;
             state->eval(e, root);
@@ -402,10 +404,10 @@ ref<eval_cache::EvalCache> openEvalCache(
     EvalState & state,
     std::shared_ptr<flake::LockedFlake> lockedFlake)
 {
-    auto fingerprint = lockedFlake->getFingerprint();
+    auto fingerprint = lockedFlake->getFingerprint(state.store);
     return make_ref<nix::eval_cache::EvalCache>(
         evalSettings.useEvalCache && evalSettings.pureEval
-            ? std::optional { std::cref(fingerprint) }
+            ? fingerprint
             : std::nullopt,
         state,
         [&state, lockedFlake]()

src/libexpr/attr-path.cc

@@ -132,7 +132,7 @@ std::pair<SourcePath, uint32_t> findPackageFilename(EvalState & state, Value & v
         if (colon == std::string::npos) fail();
         std::string filename(fn, 0, colon);
         auto lineno = std::stoi(std::string(fn, colon + 1, std::string::npos));
-        return {CanonPath(fn.substr(0, colon)), lineno};
+        return {SourcePath{path.accessor, CanonPath(fn.substr(0, colon))}, lineno};
     } catch (std::invalid_argument & e) {
         fail();
         abort();