Remove duplication from generated subexpressions

lib/handlebars/compiler/ast.js

@@ -64,6 +64,8 @@ var AST = {
       this.sexpr = new AST.SexprNode(rawParams, hash);
     }
 
+    this.sexpr.isRoot = true;
+
     // Support old AST API that stored this info in MustacheNode
     this.id = this.sexpr.id;
     this.params = this.sexpr.params;

lib/handlebars/compiler/compiler.js

@@ -281,7 +281,7 @@ Compiler.prototype = {
     } else if (this.options.knownHelpersOnly) {
       throw new Error("You specified knownHelpersOnly, but used the unknown helper " + name);
     } else {
-      this.opcode('invokeHelper', params.length, name);
+      this.opcode('invokeHelper', params.length, name, sexpr.isRoot);
     }
   },
 

lib/handlebars/compiler/javascript-compiler.js

@@ -496,18 +496,31 @@ JavaScriptCompiler.prototype = {
   // and pushes the helper's return value onto the stack.
   //
   // If the helper is not found, `helperMissing` is called.
-  invokeHelper: function(paramSize, name) {
+  invokeHelper: function(paramSize, name, isRoot) {
     this.context.aliases.helperMissing = 'helpers.helperMissing';
+    this.useRegister('helper');
 
     var helper = this.lastHelper = this.setupHelper(paramSize, name, true);
     var nonHelper = this.nameLookup('depth' + this.lastContext, name, 'context');
 
-    this.push(helper.name + ' || ' + nonHelper);
-    this.replaceStack(function(name) {
-      return name + ' ? '
-          + name + '.call(' + helper.callParams + ") "
-          + " : helperMissing.call(" + helper.helperMissingParams + ")";
-    });
+    var lookup = 'helper = ' + helper.name + ' || ' + nonHelper;
+    if (helper.paramsInit) {
+      lookup += ',' + helper.paramsInit;
+    }
+
+    this.push(
+      '('
+        + lookup
+        + ',helper '
+          + '? helper.call(' + helper.callParams + ') '
+          + ': helperMissing.call(' + helper.helperMissingParams + '))');
+
+    // Always flush subexpressions. This is both to prevent the compounding size issue that
+    // occurs when the code has to be duplicated for inlining and also to prevent errors
+    // due to the incorrect options object being passed due to the shared register.
+    if (!isRoot) {
+      this.flushInline();
+    }
   },
 
   // [invokeKnownHelper]
@@ -536,6 +549,7 @@ JavaScriptCompiler.prototype = {
   // `knownHelpersOnly` flags at compile-time.
   invokeAmbiguous: function(name, helperCall) {
     this.context.aliases.functionType = '"function"';
+    this.useRegister('helper');
 
     this.emptyHash();
     var helper = this.setupHelper(0, name, helperCall);
@@ -545,8 +559,11 @@ JavaScriptCompiler.prototype = {
     var nonHelper = this.nameLookup('depth' + this.lastContext, name, 'context');
     var nextStack = this.nextStack();
 
-    this.pushSource('if (' + nextStack + ' = ' + helperName + ') { ' + nextStack + ' = ' + nextStack + '.call(' + helper.callParams + '); }');
-    this.pushSource('else { ' + nextStack + ' = ' + nonHelper + '; ' + nextStack + ' = typeof ' + nextStack + ' === functionType ? ' + nextStack + '.call(' + helper.callParams + ') : ' + nextStack + '; }');
+    if (helper.paramsInit) {
+      this.pushSource(helper.paramsInit);
+    }
+    this.pushSource('if (helper = ' + helperName + ') { ' + nextStack + ' = helper.call(' + helper.callParams + '); }');
+    this.pushSource('else { helper = ' + nonHelper + '; ' + nextStack + ' = typeof helper === functionType ? helper.call(' + helper.callParams + ') : helper; }');
   },
 
   // [invokePartial]
@@ -807,12 +824,13 @@ JavaScriptCompiler.prototype = {
   },
 
   setupHelper: function(paramSize, name, missingParams) {
-    var params = [];
-    this.setupParams(paramSize, params, missingParams);
+    var params = [],
+        paramsInit = this.setupParams(paramSize, params, missingParams);
     var foundHelper = this.nameLookup('helpers', name, 'helper');
 
     return {
       params: params,
+      paramsInit: paramsInit,
       name: foundHelper,
       callParams: ["depth0"].concat(params).join(", "),
       helperMissingParams: missingParams && ["depth0", this.quotedString(name)].concat(params).join(", ")
@@ -870,7 +888,15 @@ JavaScriptCompiler.prototype = {
       options.push("data:data");
     }
 
-    params.push("{" + options.join(",") + "}");
+    options = "{" + options.join(",") + "}";
+    if (useRegister) {
+      this.useRegister('options');
+      params.push('options');
+      return 'options=' + options;
+    } else {
+      params.push(options);
+      return '';
+    }
   }
 };