Expose AST helpers in public API

lib/handlebars/compiler/ast.js

@@ -104,6 +104,27 @@ var AST = {
     this.type = 'HashPair';
     this.key = key;
     this.value = value;
+  },
+
+  // Public API used to evaluate derived attributes regarding AST nodes
+  helpers: {
+    // a mustache is definitely a helper if:
+    // * it is an eligible helper, and
+    // * it has at least one parameter or hash segment
+    // TODO: Make these public utility methods
+    helperExpression: function(sexpr) {
+      return !!(sexpr.isHelper || sexpr.params.length || sexpr.hash);
+    },
+
+    scopedId: function(path) {
+      return (/^\.|this\b/).test(path.original);
+    },
+
+    // an ID is simple if it only has one part, and that part is not
+    // `..` or `this`.
+    simpleId: function(path) {
+      return path.parts.length === 1 && !AST.helpers.scopedId(path) && !path.depth;
+    }
   }
 };
 

lib/handlebars/compiler/compiler.js

@@ -1,26 +1,10 @@
 import Exception from "../exception";
 import {isArray} from "../utils";
+import AST from "./ast";
 
 var slice = [].slice;
 
 
-// a mustache is definitely a helper if:
-// * it is an eligible helper, and
-// * it has at least one parameter or hash segment
-function helperExpr(sexpr) {
-  return !!(sexpr.isHelper || sexpr.params.length || sexpr.hash);
-}
-
-function scopedId(path) {
-  return (/^\.|this\b/).test(path.original);
-}
-
-// an ID is simple if it only has one part, and that part is not
-// `..` or `this`.
-function simpleId(path) {
-  return path.parts.length === 1 && !scopedId(path) && !path.depth;
-}
-
 export function Compiler() {}
 
 // the foundHelper register will disambiguate helper lookup from finding a
@@ -239,7 +223,7 @@ Compiler.prototype = {
       path.falsy = true;
 
       this.accept(path);
-      this.opcode('invokeHelper', params.length, path.original, simpleId(path));
+      this.opcode('invokeHelper', params.length, path.original, AST.helpers.simpleId(path));
     }
   },
 
@@ -255,7 +239,7 @@ Compiler.prototype = {
       this.options.data = true;
       this.opcode('lookupData', path.depth, path.parts);
     } else {
-      this.opcode('lookupOnContext', path.parts, path.falsy, scopedId(path));
+      this.opcode('lookupOnContext', path.parts, path.falsy, AST.helpers.scopedId(path));
     }
   },
 
@@ -301,12 +285,12 @@ Compiler.prototype = {
   classifySexpr: function(sexpr) {
     // a mustache is an eligible helper if:
     // * its id is simple (a single part, not `this` or `..`)
-    var isHelper = helperExpr(sexpr);
+    var isHelper = AST.helpers.helperExpression(sexpr);
 
     // if a mustache is an eligible helper but not a definite
     // helper, it is ambiguous, and will be resolved in a later
     // pass or at runtime.
-    var isEligible = isHelper || simpleId(sexpr.path);
+    var isEligible = isHelper || AST.helpers.simpleId(sexpr.path);
 
     var options = this.options;