From 60b7121d2c6d4322b7c2e8e7acfec7b701b2d3a1 Mon Sep 17 00:00:00 2001 From: John Ericson Date: Sun, 15 Jan 2023 17:39:04 -0500 Subject: Make the Derived Path family of types inductive for dynamic derivations We want to be able to write down `foo.drv^bar.drv^baz`: `foo.drv^bar.drv` is the dynamic derivation (since it is itself a derivation output, `bar.drv` from `foo.drv`). To that end, we create `Single{Derivation,BuiltPath}` types, that are very similar except instead of having multiple outputs (in a set or map), they have a single one. This is for everything to the left of the rightmost `^`. `NixStringContextElem` has an analogous change, and now can reuse `SingleDerivedPath` at the top level. In fact, if we ever get rid of `DrvDeep`, `NixStringContextElem` could be replaced with `SingleDerivedPath` entirely! Important note: some JSON formats have changed. We already can *produce* dynamic derivations, but we can't refer to them directly. Today, we can merely express building or example at the top imperatively over time by building `foo.drv^bar.drv`, and then with a second nix invocation doing `^baz`, but this is not declarative. The ethos of Nix of being able to write down the full plan everything you want to do, and then execute than plan with a single command, and for that we need the new inductive form of these types. Co-authored-by: Robert Hensing Co-authored-by: Valentin Gagarin --- src/libstore/legacy-ssh-store.cc | 3 +++ 1 file changed, 3 insertions(+) (limited to 'src/libstore/legacy-ssh-store.cc') diff --git a/src/libstore/legacy-ssh-store.cc b/src/libstore/legacy-ssh-store.cc index fa17d606d..78b05031a 100644 --- a/src/libstore/legacy-ssh-store.cc +++ b/src/libstore/legacy-ssh-store.cc @@ -358,6 +358,9 @@ public: [&](const StorePath & drvPath) { throw Error("wanted to fetch '%s' but the legacy ssh protocol doesn't support merely substituting drv files via the build paths command. It would build them instead. Try using ssh-ng://", printStorePath(drvPath)); }, + [&](std::monostate) { + throw Error("wanted build derivation that is itself a build product, but the legacy ssh protocol doesn't support that. Try using ssh-ng://"); + }, }, sOrDrvPath); } conn->to << ss; -- cgit v1.2.3