Skip to content

Commit

Permalink
Flake follows: resolve all follows to absolute
Browse files Browse the repository at this point in the history 
It's not possible in general to know in computeLocks, relative to
which path the follows was intended to be. So, we always resolve
follows to their absolute states when we encounter them (which can
either be in parseFlakeInput or computeLocks' fake input population).

Fixes NixOS#6013
Fixes NixOS#5609
Fixes NixOS#5697 (again)
  • Loading branch information
@balsoft
balsoft committed Feb 2, 2022
1 parent 73d5f38 commit 169ea0b
Show file tree
Hide file tree
Showing 2 changed files with 38 additions and 55 deletions.
87 changes: 33 additions & 54 deletions src/libexpr/flake/flake.cc
View file
Original file line number Diff line number Diff line change
Expand Up @@ -89,11 +89,11 @@ static void expectType(EvalState & state, ValueType type,

static std::map<FlakeId, FlakeInput> parseFlakeInputs(
EvalState & state, Value * value, const Pos & pos,
const std::optional<Path> & baseDir);
const std::optional<Path> & baseDir, InputPath lockRootPath);

static FlakeInput parseFlakeInput(EvalState & state,
const std::string & inputName, Value * value, const Pos & pos,
const std::optional<Path> & baseDir)
const std::optional<Path> & baseDir, InputPath lockRootPath)
{
expectType(state, nAttrs, *value, pos);

Expand All @@ -117,10 +117,12 @@ 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);
input.overrides = parseFlakeInputs(state, attr.value, *attr.pos, baseDir, lockRootPath);
} else if (attr.name == sFollows) {
expectType(state, nString, *attr.value, *attr.pos);
input.follows = parseInputPath(attr.value->string.s);
auto follows(parseInputPath(attr.value->string.s));
follows.insert(follows.begin(), lockRootPath.begin(), lockRootPath.end());
input.follows = follows;
} else {
switch (attr.value->type()) {
case nString:
Expand Down Expand Up @@ -166,7 +168,7 @@ static FlakeInput parseFlakeInput(EvalState & state,

static std::map<FlakeId, FlakeInput> parseFlakeInputs(
EvalState & state, Value * value, const Pos & pos,
const std::optional<Path> & baseDir)
const std::optional<Path> & baseDir, InputPath lockRootPath)
{
std::map<FlakeId, FlakeInput> inputs;

Expand All @@ -178,7 +180,8 @@ static std::map<FlakeId, FlakeInput> parseFlakeInputs(
inputAttr.name,
inputAttr.value,
*inputAttr.pos,
baseDir));
baseDir,
lockRootPath));
}

return inputs;
Expand All @@ -188,7 +191,8 @@ static Flake getFlake(
EvalState & state,
const FlakeRef & originalRef,
bool allowLookup,
FlakeCache & flakeCache)
FlakeCache & flakeCache,
InputPath lockRootPath)
{
auto [sourceInfo, resolvedRef, lockedRef] = fetchOrSubstituteTree(
state, originalRef, allowLookup, flakeCache);
Expand Down Expand Up @@ -223,7 +227,7 @@ 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);
flake.inputs = parseFlakeInputs(state, inputs->value, *inputs->pos, flakeDir, lockRootPath);

auto sOutputs = state.symbols.create("outputs");

Expand Down Expand Up @@ -287,6 +291,11 @@ static Flake getFlake(
return flake;
}

Flake getFlake(EvalState & state, const FlakeRef & originalRef, bool allowLookup, FlakeCache & flakeCache)
{
return getFlake(state, originalRef, allowLookup, flakeCache, {});
}

Flake getFlake(EvalState & state, const FlakeRef & originalRef, bool allowLookup)
{
FlakeCache flakeCache;
Expand Down Expand Up @@ -332,22 +341,12 @@ LockedFlake lockFlake(

std::vector<FlakeRef> parents;

struct LockParent {
/* The path to this parent. */
InputPath path;

/* Whether we are currently inside a top-level lockfile
(inputs absolute) or subordinate lockfile (inputs
relative). */
bool absolute;
};

std::function<void(
const FlakeInputs & flakeInputs,
std::shared_ptr<Node> node,
const InputPath & inputPathPrefix,
std::shared_ptr<const Node> oldNode,
const LockParent & parent,
const InputPath & lockRootPath,
const Path & parentPath,
bool trustLock)>
computeLocks;
Expand All @@ -357,7 +356,7 @@ LockedFlake lockFlake(
std::shared_ptr<Node> node,
const InputPath & inputPathPrefix,
std::shared_ptr<const Node> oldNode,
const LockParent & parent,
const InputPath & lockRootPath,
const Path & parentPath,
bool trustLock)
{
Expand Down Expand Up @@ -402,17 +401,7 @@ LockedFlake lockFlake(
if (input.follows) {
InputPath target;

if (parent.absolute && !hasOverride) {
target = *input.follows;
} else {
if (hasOverride) {
target = inputPathPrefix;
target.pop_back();
} else
target = parent.path;

for (auto & i : *input.follows) target.push_back(i);
}
target.insert(target.end(), input.follows->begin(), input.follows->end());

debug("input '%s' follows '%s'", inputPathS, printInputPath(target));
node->inputs.insert_or_assign(id, target);
Expand Down Expand Up @@ -485,23 +474,25 @@ LockedFlake lockFlake(
break;
}
}
auto absoluteFollows(lockRootPath);
absoluteFollows.insert(absoluteFollows.end(), follows->begin(), follows->end());
fakeInputs.emplace(i.first, FlakeInput {
.follows = *follows,
.follows = absoluteFollows,
});
}
}
}

LockParent newParent {
.path = inputPath,
.absolute = true
};

auto localPath(parentPath);
// If this input is a path, recurse it down.
// This allows us to resolve path inputs relative to the current flake.
if ((*input.ref).input.getType() == "path")
localPath = absPath(*input.ref->input.getSourcePath(), parentPath);
computeLocks(
mustRefetch
? getFlake(state, oldLock->lockedRef, false, flakeCache).inputs
? getFlake(state, oldLock->lockedRef, false, flakeCache, inputPath).inputs
: fakeInputs,
childNode, inputPath, oldLock, newParent, parentPath, !mustRefetch);
childNode, inputPath, oldLock, lockRootPath, parentPath, !mustRefetch);

} else {
/* We need to create a new lock file entry. So fetch
Expand All @@ -520,7 +511,7 @@ LockedFlake lockFlake(
if (localRef.input.getType() == "path")
localPath = absPath(*input.ref->input.getSourcePath(), parentPath);

auto inputFlake = getFlake(state, localRef, useRegistries, flakeCache);
auto inputFlake = getFlake(state, localRef, useRegistries, flakeCache, inputPath);

/* Note: in case of an --override-input, we use
the *original* ref (input2.ref) for the
Expand All @@ -541,13 +532,6 @@ LockedFlake lockFlake(
parents.push_back(*input.ref);
Finally cleanup([&]() { parents.pop_back(); });

// Follows paths from existing inputs in the top-level lockfile are absolute,
// whereas paths in subordinate lockfiles are relative to those lockfiles.
LockParent newParent {
.path = inputPath,
.absolute = oldLock ? true : false
};

/* Recursively process the inputs of this
flake. Also, unless we already have this flake
in the top-level lock file, use this flake's
Expand All @@ -558,7 +542,7 @@ LockedFlake lockFlake(
? std::dynamic_pointer_cast<const Node>(oldLock)
: LockFile::read(
inputFlake.sourceInfo->actualPath + "/" + inputFlake.lockedRef.subdir + "/flake.lock").root,
newParent, localPath, false);
oldLock ? lockRootPath : inputPath, localPath, false);
}

else {
Expand All @@ -576,17 +560,12 @@ LockedFlake lockFlake(
}
};

LockParent parent {
.path = {},
.absolute = true
};

// Bring in the current ref for relative path resolution if we have it
auto parentPath = canonPath(flake.sourceInfo->actualPath + "/" + flake.lockedRef.subdir, true);

computeLocks(
flake.inputs, newLockFile.root, {},
lockFlags.recreateLockFile ? nullptr : oldLockFile.root, parent, parentPath, false);
lockFlags.recreateLockFile ? nullptr : oldLockFile.root, {}, parentPath, false);

for (auto & i : lockFlags.inputOverrides)
if (!overridesUsed.count(i.first))
Expand Down
6 changes: 5 additions & 1 deletion tests/flakes.sh
View file
Original file line number Diff line number Diff line change
Expand Up @@ -730,6 +730,7 @@ cat > $flakeFollowsB/flake.nix <<EOF
description = "Flake B";
inputs = {
foobar.url = "path:$flakeFollowsA/flakeE";
goodoo.follows = "C/goodoo";
C = {
url = "path:./flakeC";
inputs.foobar.follows = "foobar";
Expand All @@ -744,6 +745,7 @@ cat > $flakeFollowsC/flake.nix <<EOF
description = "Flake C";
inputs = {
foobar.url = "path:$flakeFollowsA/flakeE";
goodoo.follows = "foobar";
};
outputs = { ... }: {};
}
Expand All @@ -759,7 +761,7 @@ EOF

cat > $flakeFollowsE/flake.nix <<EOF
{
description = "Flake D";
description = "Flake E";
inputs = {};
outputs = { ... }: {};
}
Expand All @@ -768,6 +770,8 @@ EOF
git -C $flakeFollowsA add flake.nix flakeB/flake.nix \
flakeB/flakeC/flake.nix flakeD/flake.nix flakeE/flake.nix

nix flake metadata $flakeFollowsA

nix flake update $flakeFollowsA

oldLock="$(cat "$flakeFollowsA/flake.lock")"
Expand Down

0 comments on commit 169ea0b

Please sign in to comment.