compiler: add !this.elem

bem · Jun 12, 2013 · 8165a18 · 8165a18
1 parent 5bb5afe
commit 8165a18
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Showing 2 changed files with 78 additions and 8 deletions.
diff --git a/lib/bemhtml/compiler.js b/lib/bemhtml/compiler.js
@@ -249,7 +249,45 @@ Compiler.prototype.mergeMatches = function mergeMatches(ast) {
   return ast;
 };
 
+Compiler.prototype.addNoElem = function predicates(predicates) {
+  var hasBlock = false,
+      hasElem = false,
+      hasCustom = false;
+
+  predicates.forEach(function(predicate) {
+    // this.block === ... || this.elem === ...
+    if (predicate.type === 'BinaryExpression' &&
+        predicate.operator === '===' &&
+        predicate.left.type === 'MemberExpression' &&
+        !predicate.left.computed &&
+        predicate.left.object.type === 'ThisExpression') {
+      var prop = predicate.left.property;
+      if (prop.name === 'block') hasBlock = true;
+      if (prop.name === 'elem') hasElem = true;
+    } else {
+      hasCustom = true;
+    }
+  });
+
+  // Add !this.elem
+  if (hasBlock && !hasElem && !hasCustom) {
+    predicates.push({
+      type: 'UnaryExpression',
+      operator: '!',
+      prefix: true,
+      argument: {
+        type: 'MemberExpression',
+        computed: false,
+        object: { type: 'ThisExpression' },
+        property: { type: 'Identifier', name: 'elem' }
+      }
+    });
+  }
+  return predicates;
+};
+
 Compiler.prototype.flatten = function flatten(expr) {
+  var self = this;
   function dive(expr) {
     // At this point only match(...)(match(...)(...), body) expressions are
     // present.
@@ -264,14 +302,14 @@ Compiler.prototype.flatten = function flatten(expr) {
       if (arg.bemMarked) {
         dive(arg).forEach(function(t) {
           res.push({
-            predicates: predicates.concat(t.predicates),
+            predicates: self.addNoElem(predicates.concat(t.predicates)),
             body: t.body
           });
         });
       } else {
         // Body
         res.push({
-          predicates: predicates,
+          predicates: self.addNoElem(predicates),
           body: arg
         });
       }

diff --git a/lib/bemhtml/runtime.js b/lib/bemhtml/runtime.js
@@ -1,6 +1,10 @@
 module.exports = function() {
   var __$that = this,
-      __$queue = [];
+      __$queue = [],
+      __$noElem = {},
+      __$noBlock = {},
+      __$hasElem = {},
+      __$hasBlock = {};
 
   // Called after all matches
   function __$flush() {
@@ -11,10 +15,38 @@ module.exports = function() {
         if (item && item.__$children) {
           // Sub-template
           var subcond = conditions.concat(item.__$cond);
+
+          var noBlock = item.__$cond.some(function(c) {
+            return c === __$noBlock;
+          });
+          if (!noBlock) subcond = subcond.concat(__$hasBlock);
+          var noElem = item.__$cond.some(function(c) {
+            return c === __$noElem;
+          });
+          if (!noElem) subcond = subcond.concat(__$hasElem);
+
           item.__$children.forEach(function(child) {
             apply(subcond, child);
           });
         } else {
+          var hasElemCheck = false,
+              hasBlockCheck = false;
+
+          conditions = conditions.filter(function(c) {
+            if (c === __$hasBlock) {
+              hasBlockCheck = true;
+              return false;
+            } else if (c === __$hasElem) {
+              hasElemCheck = true;
+              return false;
+            }
+            return true;
+          });
+
+          if (hasBlockCheck && !hasElemCheck) {
+            conditions = conditions.concat(!__$that.elem);
+          }
+
           // Body
           template.apply(null, conditions)(item);
         }
@@ -71,22 +103,22 @@ module.exports = function() {
   };
 
   function block(name) {
-    return match.call(this, __$that.block === name);
+    return match.call(this, __$that.block === name, __$noElem);
   };
 
   function elem(name) {
-    return match.call(this, __$that.elem === name);
+    return match.call(this, __$that.elem === name, __$noBlock);
   };
 
   function mode(name) {
-    return match.call(this, __$that._mode === name);
+    return match.call(this, __$that._mode === name, __$noElem, __$noBlock);
   };
 
   function mod(name, value) {
     return match.call(this, __$that.mods, function() {
       return __$that.mods[name] === value;
-    });
-  }
+    }, __$noElem, __$noBlock);
+  };
 
   function def() { return mode.call(this, 'default'); };
   function tag() { return mode.call(this, 'tag'); };