abstract out build comprehension helper

lib/6to5/transformation/helpers/use-strict.js

@@ -0,0 +1,19 @@
+var t = require("../../types");
+
+exports.has = function (node) {
+  var first = node.body[0];
+  return t.isExpressionStatement(first) && t.isLiteral(first.expression, { value: "use strict" });
+};
+
+exports.wrap = function (node, callback) {
+  var useStrictNode;
+  if (exports.has(node)) {
+    useStrictNode = node.body.shift();
+  }
+
+  callback();
+
+  if (useStrictNode) {
+    node.body.unshift(useStrictNode);
+  }
+};

lib/6to5/transformation/modules/system.js

@@ -1,7 +1,7 @@
 module.exports = SystemFormatter;
 
 var AMDFormatter = require("./amd");
-var useStrict    = require("../transformers/use-strict");
+var useStrict    = require("../helpers/use-strict");
 var traverse     = require("../../traverse");
 var util         = require("../../util");
 var t            = require("../../types");
@@ -171,7 +171,7 @@ SystemFormatter.prototype.transform = function (ast) {
 
   handlerBody.push(returnStatement);
 
-  if (useStrict._has(block)) {
+  if (useStrict.has(block)) {
     handlerBody.unshift(block.body.shift());
   }
 

lib/6to5/transformation/transformers/_block-hoist.js

@@ -1,4 +1,4 @@
-var useStrict = require("./use-strict");
+var useStrict = require("../helpers/use-strict");
 var _         = require("lodash");
 
 // Priority:
@@ -18,7 +18,7 @@ exports.Program = {
     }
     if (!hasChange) return;
 
-    useStrict._wrap(node, function () {
+    useStrict.wrap(node, function () {
       var nodePriorities = _.groupBy(node.body, function (bodyNode) {
         var priority = bodyNode._blockHoist;
         if (priority == null) priority = 1;

lib/6to5/transformation/transformers/_declarations.js

@@ -1,4 +1,4 @@
-var useStrict = require("./use-strict");
+var useStrict = require("../helpers/use-strict");
 var t         = require("../../types");
 
 exports.secondPass = true;
@@ -8,7 +8,7 @@ exports.Program = function (node) {
   var kinds = {};
   var kind;
 
-  useStrict._wrap(node, function () {
+  useStrict.wrap(node, function () {
     for (var i in node._declarations) {
       var declar = node._declarations[i];
 

lib/6to5/transformation/transformers/use-strict.js

@@ -1,26 +1,9 @@
-var t = require("../../types");
-
-exports._has = function (node) {
-  var first = node.body[0];
-  return t.isExpressionStatement(first) && t.isLiteral(first.expression, { value: "use strict" });
-};
-
-exports._wrap = function (node, callback) {
-  var useStrictNode;
-  if (exports._has(node)) {
-    useStrictNode = node.body.shift();
-  }
-
-  callback();
-
-  if (useStrictNode) {
-    node.body.unshift(useStrictNode);
-  }
-};
+var useStrict = require("../helpers/use-strict");
+var t         = require("../../types");
 
 exports.ast = {
   exit: function (ast) {
-    if (!exports._has(ast.program)) {
+    if (!useStrict.has(ast.program)) {
       ast.program.body.unshift(t.expressionStatement(t.literal("use strict")));
     }
   }