support for deep but exact extend

lib/less/extend-visitor.js

@@ -177,9 +177,9 @@
 
                         if (potentialMatch) {
                             potentialMatch.finished = potentialMatch.matched === extend.selector.elements.length;
-                            if (potentialMatch.finished && (
-                                (!extend.any && i+1 < selector.elements.length) ||
-                                (!extend.deep && k+1 < selectorPath.length))) {
+                            if (potentialMatch.finished &&
+                                (!extend.deep && (i+1 < selector.elements.length ||
+                                    k+1 < selectorPath.length))) {
                                 potentialMatch = null;
                             }
                         }

lib/less/parser.js

@@ -804,10 +804,6 @@ less.Parser = function Parser(env) {
                 
                 option = option && option[1];
                 
-                if (option != "all" && option) {
-                    error(":extend only supports the all option at the moment, please specify it after your selector, e.g. :extend(.a all) or specify no option to extend shallow and exact");
-                }
-                
                 if (isRule) {
                     expect(/^;/);
                 }

test/css/extend-deep.css

@@ -0,0 +1,49 @@
+.replace.replace .replace,
+.c.replace + .replace .replace,
+.replace.replace .c,
+.c.replace + .replace .c,
+.rep_ace,
+.effected.replace + .replace .replace,
+.effected.replace + .replace .c {
+  prop: copy-paste-replace;
+}
+.replace.replace .replace .d,
+.c.replace + .replace .replace .d,
+.replace.replace .c .d,
+.c.replace + .replace .c .d,
+.rep_ace .d,
+.effected.replace + .replace .replace .d,
+.effected.replace + .replace .c .d {
+  prop: deep;
+}
+.a .b .c,
+.effected .b .c {
+  prop: is_effected;
+}
+.a,
+.effected {
+  prop: is_effected;
+}
+.a .b,
+.effected .b {
+  prop: is_effected;
+}
+.a .b.c,
+.effected .b.c {
+  prop: is_effected;
+}
+.b .a {
+  prop: not_effected;
+}
+.a:hover,
+.effected:hover {
+  hover: is_effected;
+}
+.e.e,
+.dbl {
+  prop: extend-double;
+}
+.e.e:hover,
+.dbl:hover {
+  hover: up;
+}

test/css/extend-exact.css

@@ -32,3 +32,6 @@
 .dbl {
   prop: extend-double;
 }
+.e.e:hover {
+  hover: not-extended;
+}

test/less/extend-deep.less

@@ -0,0 +1,52 @@
+.replace.replace,
+.c.replace + .replace {
+  .replace,
+  .c {
+    prop: copy-paste-replace;
+    .d {
+      prop: deep;
+    }
+  }
+}
+.rep_ace:extend(.replace.replace .replace deep) {}
+
+.a .b .c {
+  prop: is_effected;
+}
+
+.a {
+  prop: is_effected;
+  .b {
+    prop: is_effected;
+  }
+  .b.c {
+    prop: is_effected;
+  }
+}
+
+.b {
+  .a {
+    prop: not_effected;
+  }
+}
+
+.a {
+  &:hover {
+    hover: is_effected;
+  }
+}
+
+.effected {
+  &:extend(.a deep);
+  &:extend(.c deep);
+}
+
+.e {
+  && {
+    prop: extend-double;
+    &:hover {
+      hover: up;
+    }
+  }
+}
+.dbl:extend(.e.e deep) {}

test/less/extend-exact.less

@@ -38,6 +38,9 @@
 .e {
   && {
     prop: extend-double;
+    &:hover {
+      hover: not-extended;
+    }
   }
 }
 .dbl:extend(.e.e) {}