Preserve whitespace in templates.

Author: blueimp

README.md

@@ -227,7 +227,23 @@ The template contents are matched and replaced using the regular expression **tm
 To use different tags for the template syntax, override **tmpl.regexp** with a modified regular expression, by exchanging all occurrences of "**\\{%**" and "**%\\}**", e.g. with "**\\[%**" and "**%\\]**":
 
 ```js
-tmpl.regexp = /(\s+)|('|\\)(?![^%]*%\])|(?:\[%(=|#)([\s\S]+?)%\])|(\[%)|(%\])/g;
+tmpl.regexp = /([\s'\\])(?![^%]*%\])|(?:\[%(=|#)([\s\S]+?)%\])|(\[%)|(%\])/g;
+```
+
+By default, the plugin preserves whitespace (newlines, carriage returns, tabs and spaces). To strip unnecessary whitespace, you can override the **tmpl.func** function, e.g. with the following code:
+
+```js
+var originalFunc = tmpl.func;
+tmpl.func = function (s, p1, p2, p3, p4, p5, offset, str) {
+    if (p1 && /\s/.test(p1)) {
+        if (!offset || /\s/.test(str.charAt(offset - 1)) ||
+                /^\s+$/g.test(str.slice(offset))) {
+            return '';
+        }
+        return ' ';
+    }
+    return originalFunc.apply(tmpl, arguments);
+};
 ```
 
 ## Templates syntax

test/test.js

@@ -17,7 +17,8 @@
     if (typeof require !== 'undefined') {
         // Override the template loading method:
         tmpl.load = function (id) {
-            return require('fs').readFileSync('./test/' + id + '.html', 'utf8');
+            return require('fs')
+                .readFileSync('./test/' + id + '.html', 'utf8');
         };
     }
 
@@ -157,6 +158,17 @@
             );
         });
 
+        it('Preserve whitespace', function () {
+            expect(
+                tmpl(
+                    '\n\r\t{%=o.value%}  \n\r\t{%=o.value%}  ',
+                    data
+                )
+            ).to.be(
+                '\n\r\tvalue  \n\r\tvalue  '
+            );
+        });
+
     });
 
     describe('Evaluation', function () {
@@ -230,7 +242,7 @@
                     '{% for (var i=0; i<o.list.length; i++) {' +
                         'include("template", {value: o.list[i]});} %}',
                     data
-                )
+                ).replace(/[\r\n]/g, '')
             ).to.be(
                 '12345'
             );

tmpl.js

@@ -34,33 +34,35 @@
     tmpl.load = function (id) {
         return document.getElementById(id).innerHTML;
     };
-    tmpl.regexp = /(\s+)|('|\\)(?![^%]*%\})|(?:\{%(=|#)([\s\S]+?)%\})|(\{%)|(%\})/g;
-    tmpl.func = function (s, p1, p2, p3, p4, p5, p6, o, str) {
-        if (p1) { // whitespace
-            return o && o + s.length !== str.length ? " " : "";
+    tmpl.regexp = /([\s'\\])(?![^%]*%\})|(?:\{%(=|#)([\s\S]+?)%\})|(\{%)|(%\})/g;
+    tmpl.func = function (s, p1, p2, p3, p4, p5) {
+        if (p1) { // whitespace, quote and backspace in interpolation context
+            return {
+                "\n": "\\n",
+                "\r": "\\r",
+                "\t": "\\t",
+                " " : " "
+            }[s] || "\\" + s;
         }
-        if (p2) { // single quote or backslash
-            return "\\" + s;
-        }
-        if (p3) { // interpolation: {%=prop%}, or unescaped: {%#prop%}
-            if (p3 === "=") {
-                return "'+_e(" + p4 + ")+'";
+        if (p2) { // interpolation: {%=prop%}, or unescaped: {%#prop%}
+            if (p2 === "=") {
+                return "'+_e(" + p3 + ")+'";
             }
-            return "'+(" + p4 + "||'')+'";
+            return "'+(" + p3 + "||'')+'";
         }
-        if (p5) { // evaluation start tag: {%
+        if (p4) { // evaluation start tag: {%
             return "';";
         }
-        if (p6) { // evaluation end tag: %}
+        if (p5) { // evaluation end tag: %}
             return "_s+='";
         }
     };
     tmpl.encReg = /[<>&"\x00]/g;
     tmpl.encMap = {
-        "<": "&lt;",
-        ">": "&gt;",
-        "&": "&amp;",
-        "\"": "&quot;",
+        "<"   : "&lt;",
+        ">"   : "&gt;",
+        "&"   : "&amp;",
+        "\""  : "&quot;",
         "\x00": ""
     };
     tmpl.encode = function (s) {