findFile: Realise the context of the path attributes

This commit is contained in:
Shea Levy 2014-05-30 15:43:31 -04:00 committed by Eelco Dolstra
parent a8fb575c98
commit 718f20da6d
2 changed files with 51 additions and 24 deletions

View file

@ -16,6 +16,7 @@ MakeError(ThrownError, AssertionError)
MakeError(Abort, EvalError)
MakeError(TypeError, EvalError)
MakeError(ImportError, EvalError) // error building an imported derivation
MakeError(FindError, EvalError) // error building a nix-path component
MakeError(UndefinedVarError, Error)

View file

@ -37,6 +37,38 @@ std::pair<string, string> decodeContext(const string & s)
}
struct InvalidPathError : EvalError
{
Path path;
InvalidPathError(const Path & path) :
EvalError(format("path `%1%' is not valid") % path), path(path) {};
};
static void realiseContext(const PathSet & context)
{
PathSet drvs;
for (auto & i : context) {
std::pair<string, string> decoded = decodeContext(i);
Path ctx = decoded.first;
assert(isStorePath(ctx));
if (!store->isValidPath(ctx))
throw InvalidPathError(ctx);
if (isDerivation(ctx))
drvs.insert(decoded.first + "!" + decoded.second);
}
if (!drvs.empty()) {
/* For performance, prefetch all substitute info. */
PathSet willBuild, willSubstitute, unknown;
unsigned long long downloadSize, narSize;
queryMissing(*store, drvs,
willBuild, willSubstitute, unknown, downloadSize, narSize);
store->buildPaths(drvs);
}
}
/* Load and evaluate an expression from path specified by the
argument. */
static void prim_scopedImport(EvalState & state, const Pos & pos, Value * * args, Value & v)
@ -44,29 +76,13 @@ static void prim_scopedImport(EvalState & state, const Pos & pos, Value * * args
PathSet context;
Path path = state.coerceToPath(pos, *args[1], context);
PathSet drvs;
for (auto & i : context) {
std::pair<string, string> decoded = decodeContext(i);
Path ctx = decoded.first;
assert(isStorePath(ctx));
if (!store->isValidPath(ctx))
throw EvalError(format("cannot import `%1%', since path `%2%' is not valid, at %3%")
% path % ctx % pos);
if (isDerivation(ctx))
drvs.insert(decoded.first + "!" + decoded.second);
}
if (!drvs.empty()) {
try {
/* For performance, prefetch all substitute info. */
PathSet willBuild, willSubstitute, unknown;
unsigned long long downloadSize, narSize;
queryMissing(*store, drvs,
willBuild, willSubstitute, unknown, downloadSize, narSize);
store->buildPaths(drvs);
} catch (Error & e) {
throw ImportError(e.msg());
}
try {
realiseContext(context);
} catch (InvalidPathError & e) {
throw EvalError(format("cannot import `%1%', since path `%2%' is not valid, at %3%")
% path % e.path % pos);
} catch (Error & e) {
throw ImportError(e.msg());
}
if (isStorePath(path) && store->isValidPath(path) && isDerivation(path)) {
@ -660,6 +676,7 @@ static void prim_findFile(EvalState & state, const Pos & pos, Value * * args, Va
SearchPath searchPath;
PathSet context;
for (unsigned int n = 0; n < args[0]->list.length; ++n) {
Value & v2(*args[0]->list.elems[n]);
state.forceAttrs(v2, pos);
@ -672,13 +689,22 @@ static void prim_findFile(EvalState & state, const Pos & pos, Value * * args, Va
i = v2.attrs->find(state.symbols.create("path"));
if (i == v2.attrs->end())
throw EvalError(format("attribute `path' missing, at %1%") % pos);
PathSet context;
string path = state.coerceToPath(pos, *i->value, context);
searchPath.push_back(std::pair<string, Path>(prefix, path));
}
string path = state.forceStringNoCtx(*args[1], pos);
try {
realiseContext(context);
} catch (InvalidPathError & e) {
throw EvalError(format("cannot find `%1%', since path `%2%' is not valid, at %3%")
% path % e.path % pos);
} catch (Error & e) {
throw FindError(e.msg());
}
mkPath(v, state.findFile(searchPath, path).c_str());
}