Test suggested word for first four letters of word

See https://github.com/iancoleman/bip39/pull/48

bip39-standalone.html

@@ -19292,8 +19292,9 @@ window.Entropy = new (function() {
         var closestWord = words[0];
         for (var i=0; i<words.length; i++) {
             var comparedTo = words[i];
-            if (comparedTo.indexOf(word) == 0) return comparedTo;
-
+            if (comparedTo.indexOf(word) == 0) {
+                return comparedTo;
+            }
             var distance = Levenshtein.get(word, comparedTo);
             if (distance < minDistance) {
                 closestWord = comparedTo;

src/js/index.js

@@ -647,8 +647,9 @@
         var closestWord = words[0];
         for (var i=0; i<words.length; i++) {
             var comparedTo = words[i];
-            if (comparedTo.indexOf(word) == 0) return comparedTo;
-
+            if (comparedTo.indexOf(word) == 0) {
+                return comparedTo;
+            }
             var distance = Levenshtein.get(word, comparedTo);
             if (distance < minDistance) {
                 closestWord = comparedTo;

tests.js

@@ -1562,6 +1562,31 @@ page.open(url, function(status) {
 });
 },
 
+// Github pull request 48
+// First four letters of word shows that word, not closest
+// since first four letters gives unique word in BIP39 wordlist
+// eg ille should show illegal, not idle
+function() {
+page.open(url, function(status) {
+    // set the incomplete word
+    page.evaluate(function() {
+        $(".phrase").val("ille").trigger("input");
+    });
+    // check there is a suggestion shown
+    waitForFeedback(function() {
+        var feedback = page.evaluate(function() {
+            return $(".feedback").text();
+        });
+        if (feedback.indexOf("did you mean illegal?") < 0) {
+            console.log("Start of word does not show correct suggestion");
+            console.log("Error: " + error);
+            fail();
+        }
+        next();
+    });
+});
+},
+
 // Incorrect BIP32 root key shows error
 function() {
 page.open(url, function(status) {