From 28d74d70685e0824b5895979d7603587c87b651b Mon Sep 17 00:00:00 2001
From: Mike Gerwitz <gerwitzm@lovullo.com>
Date: Sun, 29 Jan 2017 23:21:14 -0500
Subject: [PATCH] ValidStateMonitor: handle empty diff on past failure

See the description in the test case.  This is a bug fix.

* src/validate/ValidStateMonitor.js
  (_checkCauseFix): Do not consider an empty diff on a past failure to
    be a fix.

* test/validate/ValidStateMonitorTest.js: Add test.

DEV-2296
---
 src/validate/ValidStateMonitor.js      |  5 ++---
 test/validate/ValidStateMonitorTest.js | 19 +++++++++++++++++++
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/src/validate/ValidStateMonitor.js b/src/validate/ValidStateMonitor.js
index 59d4b66..9fb6ef5 100644
--- a/src/validate/ValidStateMonitor.js
+++ b/src/validate/ValidStateMonitor.js
@@ -298,9 +298,8 @@ module.exports = Class( 'ValidStateMonitor' )
                     // and there must be data for this index for the field
                     // in question (if the field wasn't touched, then of
                     // course there's no failure!)
-                    if ( ( fail === undefined )
-                        || ( !( fail[ cause_index ] )
-                            && ( field[ cause_index ] !== undefined ) )
+                    if ( ( ( fail === undefined ) || !( fail[ cause_index ] ) )
+                        && ( field[ cause_index ] !== undefined )
                     )
                     {
                         found( field[ cause_index ] );
diff --git a/test/validate/ValidStateMonitorTest.js b/test/validate/ValidStateMonitorTest.js
index 75dab73..52dc272 100644
--- a/test/validate/ValidStateMonitorTest.js
+++ b/test/validate/ValidStateMonitorTest.js
@@ -318,6 +318,25 @@ describe( 'ValidStateMonitor', function()
             } );
 
 
+            // if a diff is present for a previously failed key (e.g. foo),
+            // but contains no changes (e.g. [ undefined ]), and doesn't
+            // include the failure on the second call, then it should not be
+            // considered to be a fix (this is a bugfix)
+            it( 'keeps past failures on key if failure does not reoccur', () =>
+            {
+                const fail_past = mkfail( 'foo', [ 'bar', 'baz' ] );
+
+                return mkstore( { foo: [ undefined, undefined ] } )
+                    .then( data =>
+                        Sut()
+                            .update( data, { foo: fail_past } )
+                            // no failure or fix (foo has no updates)
+                            .then( sut => sut.update( data, {} ) )
+                            .then( sut => expect( sut.hasFailures() ).to.be.true )
+                    );
+            } );
+
+
             it( 'does not trigger failure event for existing', function()
             {
                 var called = 0;