String replace helper with more options

helpers.js

@@ -44,6 +44,7 @@ const helpersList = [
     'setURLQueryParam',
     'snippets',
     'stripQuerystring',
+    'strReplace',
     'stylesheet',
     'thirdParty',
     'toLowerCase',

helpers/strReplace.js

@@ -0,0 +1,54 @@
+'use strict';
+const common = require('./lib/common.js');
+const utils = require('handlebars-utils');
+
+const factory = globals => {
+    return function(str, substr, newSubstr, iteration) {
+        str = common.unwrapIfSafeString(globals.handlebars, str);
+        substr = common.unwrapIfSafeString(globals.handlebars, substr);
+        newSubstr = common.unwrapIfSafeString(globals.handlebars, newSubstr);
+        iteration = common.unwrapIfSafeString(globals.handlebars, iteration);
+
+        if (!utils.isString(str)){
+            throw new TypeError("Invalid query parameter string passed to strReplace");
+        } else if (!utils.isString(substr)){
+            throw new TypeError("Invalid query paramter substring passed to strReplace");
+        } else if(!utils.isString(newSubstr)) {
+            throw new TypeError("Invalid query parameter new substring passed to strReplace");
+        }
+
+        if (typeof iteration !== 'number') {
+            return str.replace(new RegExp(escapeRegex(substr), 'g'), newSubstr);
+        }
+
+        const occurrence = getOccurrences(str, substr);
+
+        if (iteration > 0 && occurrence > 0) {
+            if (iteration >= occurrence) {
+                return str.replace(new RegExp(escapeRegex(substr), 'g'), newSubstr);
+            } else {
+                let result = str;
+                for (let i = 0; i < iteration; i++) {
+                    result = result.replace(substr, newSubstr);
+                }
+                return result;
+            }
+        } else {
+            return str;
+        }
+    };
+};
+
+function escapeRegex(string) {
+    return string.replace(/[-\\^$*+?.()|[\]{}]/g, "\\$&");
+}
+
+function getOccurrences(str, substr) {
+    const matches = str.match(new RegExp(escapeRegex(substr),'g'));
+    return matches ? matches.length : 0;
+}
+
+module.exports = [{
+    name: 'strReplace',
+    factory: factory,
+}];

spec/helpers.js

@@ -63,6 +63,7 @@ describe('helper registration', () => {
             'setURLQueryParam',
             'snippet',
             'stripQuerystring',
+            'strReplace',
             'stylesheet',
             'after',
             'arrayify',

spec/helpers/strReplace.js

@@ -0,0 +1,68 @@
+const Lab = require('lab'),
+      lab = exports.lab = Lab.script(),
+      describe = lab.experiment,
+      it = lab.it,
+      specHelpers = require('../spec-helpers'),
+      testRunner = require('../spec-helpers').testRunner,
+      renderString = specHelpers.renderString;;
+
+describe('strReplace helper', function() {
+    const context = {
+        string: "My name is Albe Albe Albe",
+        substr: "Albe",
+        newSubstr: "Alex",
+        object: {}
+    };
+
+    const runTestCases = testRunner({context});
+
+    it('should replace all by default', function(done) {
+        runTestCases([
+            {
+                input: '{{strReplace string substr newSubstr}}',
+                output: 'My name is Alex Alex Alex',
+            },
+            {
+                input: '{{strReplace "Your name is none" "none" "Bob"}}',
+                output: 'Your name is Bob',
+            },
+        ], done);
+    });
+
+    it('should replace multiple if given quantity', function(done) {
+        runTestCases([
+            {
+                input: '{{strReplace string substr newSubstr -5}}',
+                output: 'My name is Albe Albe Albe',
+            },
+            {
+                input: '{{strReplace string substr newSubstr 0}}',
+                output: 'My name is Albe Albe Albe',
+            },
+            {
+                input: '{{strReplace string substr newSubstr 2}}',
+                output: 'My name is Alex Alex Albe',
+            },
+            {
+                input: '{{strReplace string substr newSubstr 4}}',
+                output: 'My name is Alex Alex Alex',
+            },
+            {
+                input: '{{strReplace string substr newSubstr 100}}',
+                output: 'My name is Alex Alex Alex',
+            },
+        ], done);
+    });
+
+    it('should throw an exception if the parameters have an invalid type', function(done) {
+        renderString('{{strReplace object "none" "Bob"}}').catch(e => {
+            renderString('{{strReplace "none" 3 "Bob"}}').catch(e => {
+                renderString('{{strReplace "none" "Bob" object}}').catch(e => {
+                    renderString('{{strReplace string substr newSubstr "3"}}').catch(e => {
+                        done();
+                    });
+                });
+            });
+        });
+    });
+});