Added modeling underscore.string array to string functions.

javascript/ql/lib/ext/underscore.string.model.yml

@@ -5,3 +5,4 @@ extensions:
     data:
       - ["'underscore.string'", "Member[slugify,capitalize,decapitalize,clean,cleanDiacritics,swapCase,escapeHTML,unescapeHTML,wrap,dedent,reverse,pred,succ,titleize,camelize,classify,underscored,dasherize,humanize,trim,ltrim,rtrim,truncate,sprintf,strRight,strRightBack,strLeft,strLeftBack,stripTags,unquote,map]", "Argument[0]", "ReturnValue", "taint"]
       - ["'underscore.string'", "Member[chop,chars,words,lines]", "Argument[0]", "ReturnValue", "taint"]
+      - ["'underscore.string'", "Member[toSentence,toSentenceSerial]", "Argument[0].ArrayElement", "ReturnValue", "taint"]

javascript/ql/test/library-tests/TripleDot/underscore.string.js

@@ -42,6 +42,6 @@ function strToArray() {
 }
 
 function arrayToStr() {
-  sink(s.toSentence([source("s1")])); // $ MISSING: hasTaintFlow=s1
-  sink(s.toSentenceSerial([source("s2")])); // $ MISSING: hasTaintFlow=s2
+  sink(s.toSentence([source("s1")])); // $ hasTaintFlow=s1
+  sink(s.toSentenceSerial([source("s2")])); // $ hasTaintFlow=s2
 }