Add ignoreStandalone compiler option

Fixes #1072

Author: kpdecker

lib/handlebars/compiler/base.js

@@ -20,6 +20,6 @@ export function parse(input, options) {
     return new yy.SourceLocation(options && options.srcName, locInfo);
   };
 
-  let strip = new WhitespaceControl();
+  let strip = new WhitespaceControl(options);
   return strip.accept(parser.parse(input));
 }

lib/handlebars/compiler/whitespace-control.js

@@ -1,10 +1,13 @@
 import Visitor from './visitor';
 
-function WhitespaceControl() {
+function WhitespaceControl(options = {}) {
+  this.options = options;
 }
 WhitespaceControl.prototype = new Visitor();
 
 WhitespaceControl.prototype.Program = function(program) {
+  const doStandalone = !this.options.ignoreStandalone;
+
   let isRoot = !this.isRootSeen;
   this.isRootSeen = true;
 
@@ -31,7 +34,7 @@ WhitespaceControl.prototype.Program = function(program) {
       omitLeft(body, i, true);
     }
 
-    if (inlineStandalone) {
+    if (doStandalone && inlineStandalone) {
       omitRight(body, i);
 
       if (omitLeft(body, i)) {
@@ -42,13 +45,13 @@ WhitespaceControl.prototype.Program = function(program) {
         }
       }
     }
-    if (openStandalone) {
+    if (doStandalone && openStandalone) {
       omitRight((current.program || current.inverse).body);
 
       // Strip out the previous content node if it's whitespace only
       omitLeft(body, i);
     }
-    if (closeStandalone) {
+    if (doStandalone && closeStandalone) {
       // Always strip the next node
       omitRight(body, i);
 
@@ -106,7 +109,8 @@ WhitespaceControl.prototype.BlockStatement = function(block) {
     }
 
     // Find standalone else statments
-    if (isPrevWhitespace(program.body)
+    if (!this.options.ignoreStandalone
+        && isPrevWhitespace(program.body)
         && isNextWhitespace(firstInverse.body)) {
       omitLeft(program.body);
       omitRight(firstInverse.body);

spec/blocks.js

@@ -125,6 +125,16 @@ describe('blocks', function() {
       shouldCompileTo('{{#people}}\n{{name}}\n{{^}}\n{{none}}\n{{/people}}\n', {none: 'No people'},
         'No people\n');
     });
+    it('block standalone else sections can be disabled', function() {
+      shouldCompileTo(
+        '{{#people}}\n{{name}}\n{{^}}\n{{none}}\n{{/people}}\n',
+        [{none: 'No people'}, {}, {}, {ignoreStandalone: true}],
+        '\nNo people\n\n');
+      shouldCompileTo(
+        '{{#none}}\n{{.}}\n{{^}}\nFail\n{{/none}}\n',
+        [{none: 'No people'}, {}, {}, {ignoreStandalone: true}],
+        '\nNo people\n\n');
+    });
     it('block standalone chained else sections', function() {
       shouldCompileTo('{{#people}}\n{{name}}\n{{else if none}}\n{{none}}\n{{/people}}\n', {none: 'No people'},
         'No people\n');