From acf7aab588b162ddf238d12c02f8a0569dd2c4e5 Mon Sep 17 00:00:00 2001
From: Eddie Antonio Santos <easantos@ualberta.ca>
Date: Tue, 28 Apr 2020 15:55:01 -0600
Subject: [PATCH] refactor(common/lmlayer): extract function:
 spansAreBackToBack

---
 .../word_breaking/join-word-breaker-decorator.ts    | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/common/predictive-text/worker/word_breaking/join-word-breaker-decorator.ts b/common/predictive-text/worker/word_breaking/join-word-breaker-decorator.ts
index 21838f564a..3b74fccbdc 100644
--- a/common/predictive-text/worker/word_breaking/join-word-breaker-decorator.ts
+++ b/common/predictive-text/worker/word_breaking/join-word-breaker-decorator.ts
@@ -46,12 +46,13 @@ namespace wordBreakers {
         let current: Span | undefined = results[index];
 
         let window = [];
-        if (previous && previous.end === current.start) {
+        if (previous && spansAreBackToBack(previous, current)) {
           window.push(index - 1);
         }
+
         window.push(index);
 
-        if (next && current.end === next.start) {
+        if (next && spansAreBackToBack(current, next)) {
           window.push(index + 1);
         }
 
@@ -92,6 +93,14 @@ namespace wordBreakers {
       return contiguousRanges;
     }
 
+    /**
+     * Returns true when the spans are contiguous.
+     * Order matters when calling this function!
+     */
+    function spansAreBackToBack(former: Span, latter: Span): boolean {
+      return former.end === latter.start;
+    }
+
     /**
      * Given an array of ranges of indices, and the corresponding spans,
      * concatenates spans according to the ranges of indices.