Add url REPLACE macro (ampproject#13130)

* add-replace-filter

* Refactor space handling

* Toggle off next arg

* Do what test describes

extensions/amp-analytics/0.1/test/test-variables.js

@@ -193,6 +193,34 @@ describe('amp-analytics.VariableService', function() {
                 'S7Uc5ZmODduHWdplzrZ7Jsnqx')
           );
     });
+
+    it('replaces common use case', () => {
+      return check('REPLACE(this-is-a-test, `-`)', 'thisisatest');
+    });
+
+    it('replaces three args', () => {
+      return check('REPLACE(this-is-a-test, `-`, *)', 'this*is*a*test');
+    });
+
+    it('replaces backticks optional', () => {
+      return check('REPLACE(this-is-a-test, -, **)', 'this**is**a**test');
+    });
+
+    it('replaces not trimming spaces in backticks', () => {
+      return check('REPLACE(this-is-a-test, ` -`)', 'this-is-a-test');
+    });
+
+    it('replaces respecting space as arg', () => {
+      return check('REPLACE(this-is-a-test, `-`, ` `)', 'this%20is%20a%20test');
+    });
+
+    it('replaces respecting backticks', () => {
+      return check('REPLACE(`this-,is-,a-,test`, `-,`)', 'thisisatest');
+    });
+
+    it('replace with no third arg', () => {
+      return check('REPLACE(thi@s-is-a-te@st, `-|@`)', 'thisisatest');
+    });
   });
 
   describe('getNameArgs:', () => {

extensions/amp-analytics/0.1/variables.js

@@ -98,6 +98,23 @@ function defaultMacro(value, defaultValue) {
   return value;
 }
 
+/**
+ * @param {string} string input to be replaced
+ * @param {string} matchPattern string representation of regex pattern
+ * @param {string=} opt_newSubStr pattern to be substituted in
+ * @returns {string}
+ */
+function replaceMacro(string, matchPattern, opt_newSubStr) {
+  if (!matchPattern) {
+    user().warn(TAG, 'REPLACE macro must have two or more arguments');
+  }
+  if (!opt_newSubStr) {
+    opt_newSubStr = '';
+  }
+  const regex = new RegExp(matchPattern, 'g');
+  return string.replace(regex, opt_newSubStr);
+}
+
 
 /**
  * Provides support for processing of advanced variable syntax like nested
@@ -126,6 +143,7 @@ export class VariableService {
     this.register_('HASH', this.hashMacro_.bind(this));
     this.register_('IF',
         (value, thenValue, elseValue) => value ? thenValue : elseValue);
+    this.register_('REPLACE', replaceMacro);
   }
 
   /**

src/service/url-expander/expander.js

@@ -16,6 +16,8 @@
 
 import {rethrowAsync} from '../../log';
 
+export const PARSER_IGNORE_FLAG = '`';
+
 /** Rudamentary parser to handle nested Url replacement. */
 export class Expander {
 
@@ -86,13 +88,14 @@ export class Expander {
     let matchIndex = 0;
     let match = matches[matchIndex];
     let numOfPendingCalls = 0;
+    let ignoringChars = false;
+    let nextArgShouldBeRaw = false;
 
     const evaluateNextLevel = () => {
       let builder = '';
       const results = [];
 
       while (urlIndex < url.length && matchIndex <= matches.length) {
-
         if (match && urlIndex === match.start) {
           let binding;
           // find out where this keyword is coming from
@@ -127,25 +130,40 @@ export class Expander {
           builder = '';
         }
 
-        else if (numOfPendingCalls && url[urlIndex] === ',') {
+        else if (url[urlIndex] === PARSER_IGNORE_FLAG) {
+          if (!ignoringChars) {
+            ignoringChars = true;
+            nextArgShouldBeRaw = true;
+            builder = '';
+          } else {
+            ignoringChars = false;
+          }
+          urlIndex++;
+        }
+
+        else if (numOfPendingCalls && url[urlIndex] === ',' && !ignoringChars) {
           if (builder.length) {
-            results.push(builder.trim());
+            const nextArg = nextArgShouldBeRaw ? builder : builder.trim();
+            results.push(nextArg);
+            nextArgShouldBeRaw = false;
           }
           // support existing two comma format
           // eg CLIENT_ID(__ga,,ga-url)
           if (url[urlIndex + 1] === ',') {
-            results.push('');
+            results.push(''); // TODO(ccordry): may want this to be undefined at some point
             urlIndex++;
           }
           builder = '';
           urlIndex++;
         }
 
-        else if (url[urlIndex] === ')') {
+        else if (url[urlIndex] === ')' && !ignoringChars) {
           urlIndex++;
           numOfPendingCalls--;
           const binding = stack.pop();
-          results.push(builder.trim());
+          const nextArg = nextArgShouldBeRaw ? builder : builder.trim();
+          results.push(nextArg);
+          nextArgShouldBeRaw = false;
           const value = this.evaluateBinding_(binding, results);
           return value;
         }

test/functional/url-expander/test-expander.js

@@ -174,6 +174,24 @@ describes.realWin('Expander', {
       return expect(expander.expand('TRIM(FAKE(aaaaa))', mockBindings))
           .to.eventually.equal('');
     });
+
+    it('ignores commas within backticks', () => {
+      const url = 'CONCAT(`he,llo`,UPPERCASE(world)';
+      return expect(expander.expand(url, mockBindings))
+          .to.eventually.equal('he,lloWORLD');
+    });
+
+    it('ignores left parentheses within backticks', () => {
+      const url = 'CONCAT(hello, `wo((rld`)';
+      return expect(expander.expand(url, mockBindings))
+          .to.eventually.equal('hellowo((rld');
+    });
+
+    it('ignores right parentheses within backticks', () => {
+      const url = 'CONCAT(`hello)`,UPPERCASE(world)';
+      return expect(expander.expand(url, mockBindings))
+          .to.eventually.equal('hello)WORLD');
+    });
   });
 });