* When obtaining derivations from Nix expressions, ignore all

expressions that cause an assertion failure (like `assert system ==
  "i686-linux"').  This allows all-packages.nix in Nixpkgs to be used
  on all platforms, even if some Nix expressions don't work on all
  platforms.

  Not sure if this is a good idea; it's a bit hacky.  In particular,
  due to laziness some derivations might appear in `nix-env -qa' but
  disappear in `nix-env -qas' or `nix-env -i'.

  Commit 5000!
This commit is contained in:
Eelco Dolstra 2006-03-08 16:03:58 +00:00
parent 9088dee9e2
commit 6dca5c9099
3 changed files with 98 additions and 70 deletions

View file

@ -383,7 +383,13 @@ Expr evalExpr(EvalState & state, Expr e)
/* Otherwise, evaluate and memoize. */
state.normalForms.set(e, state.blackHole);
try {
nf = evalExpr2(state, e);
} catch (Error & err) {
debug("removing black hole");
state.normalForms.remove(e);
throw;
}
state.normalForms.set(e, nf);
return nf;
}

View file

@ -5,22 +5,29 @@
typedef set<Expr> Exprs;
/* Evaluate expression `e'. If it evaluates to an attribute set of
type `derivation', then put information about it in `drvs' (unless
it's already in `doneExprs'). The result boolean indicates whether
it makes sense for the caller to recursively search for derivations
in `e'. */
static bool getDerivation(EvalState & state, Expr e,
DrvInfos & drvs, Exprs & doneExprs)
{
try {
ATermList es;
e = evalExpr(state, e);
if (!matchAttrs(e, es)) return false;
if (!matchAttrs(e, es)) return true;
ATermMap attrs;
queryAllAttrs(e, attrs, false);
Expr a = attrs.get("type");
if (!a || evalString(state, a) != "derivation") return false;
if (!a || evalString(state, a) != "derivation") return true;
/* Remove spurious duplicates (e.g., an attribute set like `rec {
x = derivation {...}; y = x;}'. */
if (doneExprs.find(e) != doneExprs.end()) return true;
/* Remove spurious duplicates (e.g., an attribute set like
`rec { x = derivation {...}; y = x;}'. */
if (doneExprs.find(e) != doneExprs.end()) return false;
doneExprs.insert(e);
DrvInfo drv;
@ -38,7 +45,11 @@ static bool getDerivation(EvalState & state, Expr e,
drv.attrs = attrs;
drvs.push_back(drv);
return true;
return false;
} catch (AssertionError & e) {
return false;
}
}
@ -46,9 +57,10 @@ bool getDerivation(EvalState & state, Expr e, DrvInfo & drv)
{
Exprs doneExprs;
DrvInfos drvs;
bool result = getDerivation(state, e, drvs, doneExprs);
if (result) drv = drvs.front();
return result;
getDerivation(state, e, drvs, doneExprs);
if (drvs.size() != 1) return false;
drv = drvs.front();
return true;
}
@ -101,26 +113,28 @@ static void getDerivations(EvalState & state, Expr e,
ATermList es;
DrvInfo drv;
e = evalExpr(state, e);
if (getDerivation(state, e, drvs, doneExprs)) {
if (!getDerivation(state, e, drvs, doneExprs)) {
if (apType != apNone) throw attrError;
return;
}
e = evalExpr(state, e);
if (matchAttrs(e, es)) {
if (apType != apNone && apType != apAttr) throw attrError;
ATermMap drvMap;
queryAllAttrs(e, drvMap);
if (apType == apNone) {
for (ATermIterator i(drvMap.keys()); i; ++i) {
debug(format("evaluating attribute `%1%'") % aterm2String(*i));
startNest(nest, lvlDebug,
format("evaluating attribute `%1%'") % aterm2String(*i));
getDerivation(state, drvMap.get(*i), drvs, doneExprs);
}
} else {
Expr e2 = drvMap.get(attr);
if (!e2) throw Error(format("attribute `%1%' in selection path not found") % attr);
debug(format("evaluating attribute `%1%'") % attr);
startNest(nest, lvlDebug,
format("evaluating attribute `%1%'") % attr);
getDerivation(state, e2, drvs, doneExprs);
if (!attrPath.empty())
getDerivations(state, e2, drvs, doneExprs, attrPathRest);
@ -132,14 +146,16 @@ static void getDerivations(EvalState & state, Expr e,
if (apType != apNone && apType != apIndex) throw attrError;
if (apType == apNone) {
for (ATermIterator i(es); i; ++i) {
debug(format("evaluating list element"));
startNest(nest, lvlDebug,
format("evaluating list element"));
if (!getDerivation(state, *i, drvs, doneExprs))
getDerivations(state, *i, drvs, doneExprs, attrPathRest);
}
} else {
Expr e2 = ATelementAt(es, attrIndex);
if (!e2) throw Error(format("list index %1% in selection path not found") % attrIndex);
debug(format("evaluating list element"));
startNest(nest, lvlDebug,
format("evaluating list element"));
if (!getDerivation(state, e2, drvs, doneExprs))
getDerivations(state, e2, drvs, doneExprs, attrPathRest);
}

View file

@ -762,6 +762,8 @@ static void opQuery(Globals & globals,
for (vector<DrvInfo>::iterator i = elems2.begin();
i != elems2.end(); ++i)
{
try {
Strings columns;
if (printStatus) {
@ -776,10 +778,10 @@ static void opQuery(Globals & globals,
if (printName) columns.push_back(i->name);
if (compareVersions) {
/* Compare this element against the versions of the same
named packages in either the set of available elements,
or the set of installed elements. !!! This is O(N *
M), should be O(N * lg M). */
/* Compare this element against the versions of the
same named packages in either the set of available
elements, or the set of installed elements. !!!
This is O(N * M), should be O(N * lg M). */
string version;
VersionDiff diff = compareVersionAgainstSet(*i, otherElems, version);
char ch;
@ -802,8 +804,12 @@ static void opQuery(Globals & globals,
? "-" : i->queryDrvPath(globals.state));
if (printOutPath) columns.push_back(i->queryOutPath(globals.state));
table.push_back(columns);
}
catch (AssertionError & e) {
}
}
printTable(table);
}