Fold dynamic binds handling into addAttr

Since addAttr has to iterate through the AttrPath we pass it, it makes
more sense to just iterate through the AttrNames in addAttr instead. As
an added bonus, this allows attrsets where two dynamic attribute paths
have the same static leading part (see added test case for an example
that failed previously).

Signed-off-by: Shea Levy <shea@shealevy.com>

src/libexpr/parser.y

@@ -89,31 +89,47 @@ static void dupAttr(Symbol attr, const Pos & pos, const Pos & prevPos)
 }
 
 
-static void addAttr(ExprAttrs * attrs, AttrPath & attrPath,
+static void addAttr(ExprAttrs * attrs, AttrNames & attrNames,
     Expr * e, const Pos & pos)
 {
-    unsigned int n = 0;
+    AttrPath path;
-    foreach (AttrPath::const_iterator, i, attrPath) {
+    AttrNames::iterator i;
-        n++;
+    // All attrpaths have at least one attr
-        ExprAttrs::AttrDefs::iterator j = attrs->attrs.find(*i);
+    assert(!attrNames.empty());
+    for (i = attrNames.begin(); i + 1 < attrNames.end(); i++) {
+        if (i->symbol.set()) {
+            path.push_back(i->symbol);
+            ExprAttrs::AttrDefs::iterator j = attrs->attrs.find(i->symbol);
             if (j != attrs->attrs.end()) {
                 if (!j->second.inherited) {
                     ExprAttrs * attrs2 = dynamic_cast<ExprAttrs *>(j->second.e);
-                if (!attrs2 || n == attrPath.size()) dupAttr(attrPath, pos, j->second.pos);
+                    if (!attrs2) dupAttr(path, pos, j->second.pos);
                     attrs = attrs2;
                 } else
-                dupAttr(attrPath, pos, j->second.pos);
+                    dupAttr(path, pos, j->second.pos);
             } else {
-            if (n == attrPath.size())
+                path.clear();
-                attrs->attrs[*i] = ExprAttrs::AttrDef(e, pos);
-            else {
                 ExprAttrs * nested = new ExprAttrs;
-                attrs->attrs[*i] = ExprAttrs::AttrDef(nested, pos);
+                attrs->attrs[i->symbol] = ExprAttrs::AttrDef(nested, pos);
+                attrs = nested;
+            }
+        } else {
+            ExprAttrs *nested = new ExprAttrs;
+            attrs->dynamicAttrs.push_back(ExprAttrs::DynamicAttrDef(i->expr, nested, pos));
             attrs = nested;
         }
     }
+    if (i->symbol.set()) {
+        ExprAttrs::AttrDefs::iterator j = attrs->attrs.find(i->symbol);
+        if (j != attrs->attrs.end()) {
+            dupAttr(path, pos, j->second.pos);
+        } else {
+            attrs->attrs[i->symbol] = ExprAttrs::AttrDef(e, pos);
+            e->setName(i->symbol);
+        }
+    } else {
+        attrs->dynamicAttrs.push_back(ExprAttrs::DynamicAttrDef(i->expr, e, pos));
     }
-    e->setName(attrPath.back());
 }
 
 
@@ -522,43 +538,7 @@ ind_string_parts
   ;
 
 binds
-  : binds attrpath '=' expr ';'
+  : binds attrpath '=' expr ';' { $$ = $1; addAttr($$, *$2, $4, makeCurPos(@2, data)); }
-    {
-        ExprAttrs *curAttrs = $1;
-        AttrPath path;
-        vector<AttrName>::iterator i;
-        // All attrpaths have at least one attr
-        assert(!$2->empty());
-        for (i = $2->begin(); i + 1 < $2->end(); i++) {
-          if (i->symbol.set()) {
-            path.push_back(i->symbol);
-          } else {
-            ExprAttrs *temp;
-            if (!path.empty()) {
-              temp = curAttrs;
-              curAttrs = new ExprAttrs;
-              addAttr(temp, path, curAttrs, makeCurPos(@2, data));
-            }
-            path.clear();
-
-            temp = curAttrs;
-            curAttrs = new ExprAttrs;
-            temp->dynamicAttrs.push_back(ExprAttrs::DynamicAttrDef(i->expr, curAttrs, makeCurPos(@2, data)));
-          }
-        }
-        if (i->symbol.set()) {
-          path.push_back(i->symbol);
-          addAttr(curAttrs, path, $4, makeCurPos(@2, data));
-        } else {
-          if (!path.empty()) {
-            ExprAttrs *temp = curAttrs;
-            curAttrs = new ExprAttrs;
-            addAttr(temp, path, curAttrs, makeCurPos(@2, data));
-          }
-          curAttrs->dynamicAttrs.push_back(ExprAttrs::DynamicAttrDef(i->expr, $4, makeCurPos(@2, data)));
-        }
-        $$ = $1;
-    }
   | binds INHERIT attrs ';'
     { $$ = $1;
       foreach (AttrPath::iterator, i, *$3) {

tests/lang/eval-okay-dynamic-attrs-2.exp

@@ -0,0 +1 @@
+true

tests/lang/eval-okay-dynamic-attrs-2.nix

@@ -0,0 +1 @@
+{ a."${"b"}" = true; a."${"c"}" = false; }.a.b