Merge pull request #6621 from Kha/nested-follows

Fix nested flake input overrides
This commit is contained in:
Théophane Hufschmitt 2022-09-01 12:04:00 +02:00 committed by GitHub
commit c530cda345
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3 changed files with 95 additions and 14 deletions

View file

@ -90,11 +90,11 @@ static void expectType(EvalState & state, ValueType type,
static std::map<FlakeId, FlakeInput> parseFlakeInputs(
EvalState & state, Value * value, const PosIdx pos,
const std::optional<Path> & baseDir, InputPath lockRootPath);
const std::optional<Path> & baseDir, InputPath lockRootPath, unsigned depth);
static FlakeInput parseFlakeInput(EvalState & state,
const std::string & inputName, Value * value, const PosIdx pos,
const std::optional<Path> & baseDir, InputPath lockRootPath)
const std::optional<Path> & baseDir, InputPath lockRootPath, unsigned depth)
{
expectType(state, nAttrs, *value, pos);
@ -118,7 +118,7 @@ static FlakeInput parseFlakeInput(EvalState & state,
expectType(state, nBool, *attr.value, attr.pos);
input.isFlake = attr.value->boolean;
} else if (attr.name == sInputs) {
input.overrides = parseFlakeInputs(state, attr.value, attr.pos, baseDir, lockRootPath);
input.overrides = parseFlakeInputs(state, attr.value, attr.pos, baseDir, lockRootPath, depth + 1);
} else if (attr.name == sFollows) {
expectType(state, nString, *attr.value, attr.pos);
auto follows(parseInputPath(attr.value->string.s));
@ -163,7 +163,11 @@ static FlakeInput parseFlakeInput(EvalState & state,
input.ref = parseFlakeRef(*url, baseDir, true, input.isFlake);
}
if (!input.follows && !input.ref)
if (!input.follows && !input.ref && depth == 0)
// in `input.nixops.inputs.nixpkgs.url = ...`, we assume `nixops` is from
// the flake registry absent `ref`/`follows`, but we should not assume so
// about `nixpkgs` (where `depth == 1`) as the `nixops` flake should
// determine its default source
input.ref = FlakeRef::fromAttrs({{"type", "indirect"}, {"id", inputName}});
return input;
@ -171,7 +175,7 @@ static FlakeInput parseFlakeInput(EvalState & state,
static std::map<FlakeId, FlakeInput> parseFlakeInputs(
EvalState & state, Value * value, const PosIdx pos,
const std::optional<Path> & baseDir, InputPath lockRootPath)
const std::optional<Path> & baseDir, InputPath lockRootPath, unsigned depth)
{
std::map<FlakeId, FlakeInput> inputs;
@ -184,7 +188,8 @@ static std::map<FlakeId, FlakeInput> parseFlakeInputs(
inputAttr.value,
inputAttr.pos,
baseDir,
lockRootPath));
lockRootPath,
depth));
}
return inputs;
@ -230,7 +235,7 @@ static Flake getFlake(
auto sInputs = state.symbols.create("inputs");
if (auto inputs = vInfo.attrs->get(sInputs))
flake.inputs = parseFlakeInputs(state, inputs->value, inputs->pos, flakeDir, lockRootPath);
flake.inputs = parseFlakeInputs(state, inputs->value, inputs->pos, flakeDir, lockRootPath, 0);
auto sOutputs = state.symbols.create("outputs");
@ -313,6 +318,19 @@ Flake getFlake(EvalState & state, const FlakeRef & originalRef, bool allowLookup
return getFlake(state, originalRef, allowLookup, flakeCache);
}
/* Recursively merge `overrides` into `overrideMap` */
static void updateOverrides(std::map<InputPath, FlakeInput> & overrideMap, const FlakeInputs & overrides,
const InputPath & inputPathPrefix)
{
for (auto & [id, input] : overrides) {
auto inputPath(inputPathPrefix);
inputPath.push_back(id);
// Do not override existing assignment from outer flake
overrideMap.insert({inputPath, input});
updateOverrides(overrideMap, input.overrides, inputPath);
}
}
/* Compute an in-memory lock file for the specified top-level flake,
and optionally write it to file, if the flake is writable. */
LockedFlake lockFlake(
@ -375,12 +393,9 @@ LockedFlake lockFlake(
/* Get the overrides (i.e. attributes of the form
'inputs.nixops.inputs.nixpkgs.url = ...'). */
for (auto & [id, input] : flakeInputs) {
for (auto & [idOverride, inputOverride] : input.overrides) {
auto inputPath(inputPathPrefix);
inputPath.push_back(id);
inputPath.push_back(idOverride);
overrides.insert_or_assign(inputPath, inputOverride);
}
updateOverrides(overrides, input.overrides, inputPath);
}
/* Check whether this input has overrides for a
@ -415,6 +430,12 @@ LockedFlake lockFlake(
// Respect the “flakeness” of the input even if we
// override it
i->second.isFlake = input2.isFlake;
if (!i->second.ref)
i->second.ref = input2.ref;
if (!i->second.follows)
i->second.follows = input2.follows;
// Note that `input.overrides` is not used in the following,
// so no need to merge it here (already done by `updateOverrides`)
}
auto & input = hasOverride ? i->second : input2;

View file

@ -338,7 +338,7 @@ void LockFile::check()
for (auto & [inputPath, input] : inputs) {
if (auto follows = std::get_if<1>(&input)) {
if (!follows->empty() && !get(inputs, *follows))
if (!follows->empty() && !findInput(*follows))
throw Error("input '%s' follows a non-existent input '%s'",
printInputPath(inputPath),
printInputPath(*follows));

View file

@ -148,3 +148,63 @@ git -C $flakeFollowsA add flake.nix
nix flake lock $flakeFollowsA 2>&1 | grep "warning: input 'B' has an override for a non-existent input 'invalid'"
nix flake lock $flakeFollowsA 2>&1 | grep "warning: input 'B' has an override for a non-existent input 'invalid2'"
# Test nested flake overrides: A overrides B/C/D
cat <<EOF > $flakeFollowsD/flake.nix
{ outputs = _: {}; }
EOF
cat <<EOF > $flakeFollowsC/flake.nix
{
inputs.D.url = "path:nosuchflake";
outputs = _: {};
}
EOF
cat <<EOF > $flakeFollowsB/flake.nix
{
inputs.C.url = "path:$flakeFollowsC";
outputs = _: {};
}
EOF
cat <<EOF > $flakeFollowsA/flake.nix
{
inputs.B.url = "path:$flakeFollowsB";
inputs.D.url = "path:$flakeFollowsD";
inputs.B.inputs.C.inputs.D.follows = "D";
outputs = _: {};
}
EOF
nix flake lock $flakeFollowsA
[[ $(jq -c .nodes.C.inputs.D $flakeFollowsA/flake.lock) = '["D"]' ]]
# Test overlapping flake follows: B has D follow C/D, while A has B/C follow C
cat <<EOF > $flakeFollowsC/flake.nix
{
inputs.D.url = "path:$flakeFollowsD";
outputs = _: {};
}
EOF
cat <<EOF > $flakeFollowsB/flake.nix
{
inputs.C.url = "path:nosuchflake";
inputs.D.url = "path:nosuchflake";
inputs.D.follows = "C/D";
outputs = _: {};
}
EOF
cat <<EOF > $flakeFollowsA/flake.nix
{
inputs.B.url = "path:$flakeFollowsB";
inputs.C.url = "path:$flakeFollowsC";
inputs.B.inputs.C.follows = "C";
outputs = _: {};
}
EOF
# bug was not triggered without recreating the lockfile
nix flake lock $flakeFollowsA --recreate-lock-file
[[ $(jq -c .nodes.B.inputs.D $flakeFollowsA/flake.lock) = '["B","C","D"]' ]]