Merge pull request mde#272 from User4martin/optimize_include_performance

use only one __output array for template and includes
zhaoguangyue · Jul 16, 2017 · 8aaa120 · 8aaa120
2 parents 6f8421b + e32869d
commit 8aaa120
Showing 1 changed file with 20 additions and 6 deletions.
diff --git a/lib/ejs.js b/lib/ejs.js
@@ -481,12 +481,20 @@ Template.prototype = {
 
     if (!this.source) {
       this.generateSource();
-      prepended += '  var __output = [], __append = __output.push.bind(__output);' + '\n';
+      if (opts.client) {
+        prepended += 'var __output = [], __append = callerAppend || __output.push.bind(__output);' + '\n';
+      }
+      else {
+        prepended += 'var __append = callerAppend;' + '\n';
+      }
+
       if (opts._with !== false) {
         prepended +=  '  with (' + opts.localsName + ' || {}) {' + '\n';
         appended += '  }' + '\n';
       }
-      appended += '  return __output.join("");' + '\n';
+      if (opts.client) {
+        appended += '  if (! callerAppend) { return __output.join("");} ' + '\n';
+      }
       this.source = prepended + this.source + appended;
     }
 
@@ -521,7 +529,7 @@ Template.prototype = {
     }
 
     try {
-      fn = new Function(opts.localsName + ', escapeFn, include, rethrow', src);
+      fn = new Function(opts.localsName + ', escapeFn, include, rethrow, callerAppend', src);
     }
     catch(e) {
       // istanbul ignore else
@@ -544,15 +552,21 @@ Template.prototype = {
     // Return a callable function which will execute the function
     // created by the source-code, with the passed data as locals
     // Adds a local `include` function which allows full recursive include
-    var returnedFn = function (data) {
+    var returnedFn = function (data, callerAppend) {
+      var __output, __append = callerAppend;
+      if (! callerAppend) {
+        __output = [];
+        __append =  __output.push.bind(__output);
+      }
       var include = function (path, includeData) {
         var d = utils.shallowCopy({}, data);
         if (includeData) {
           d = utils.shallowCopy(d, includeData);
         }
-        return includeFile(path, opts)(d);
+        return includeFile(path, opts)(d, __append);
       };
-      return fn.apply(opts.context, [data || {}, escapeFn, include, rethrow]);
+      fn.apply(opts.context, [data || {}, escapeFn, include, rethrow, __append]);
+      if (! callerAppend) { return __output.join(''); }
     };
     returnedFn.dependencies = this.dependencies;
     return returnedFn;