From 93ad18c4bb7c15854ad31ac3f530d87df5874453 Mon Sep 17 00:00:00 2001
From: Soroush Saffari <soroush@grakn.ai>
Date: Fri, 19 Jun 2020 12:20:17 +0100
Subject: [PATCH] Fixes a bug where `getRule` gets run on a joint explanation
 (#300)

## What is the goal of this PR?
Explanation now works as expected when the first explanation is joint. This marks the 1.3.1 release.

## What are the changes implemented in this PR?
While introducing this fix I came to realise that the _unassigned variables_ error message will not be displayed when the target explanation is within the answers of the joint explanation. I have created an issue for it with high priority: https://github.com/graknlabs/workbase/issues/299
---
 VERSION                                             | 2 +-
 package.json                                        | 2 +-
 src/renderer/components/Visualiser/store/actions.js | 6 ++++--
 3 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/VERSION b/VERSION
index 589268e6f..6261a05bb 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.3.0
\ No newline at end of file
+1.3.1
\ No newline at end of file
diff --git a/package.json b/package.json
index f70eacb6e..73a3efb8b 100644
--- a/package.json
+++ b/package.json
@@ -165,5 +165,5 @@
         "prebuild": "node version.js",
         "unit": "node ./node_modules/jest/bin/jest.js ./test/unit"
     },
-    "version": "1.3.0"
+    "version": "1.3.1"
 }
\ No newline at end of file
diff --git a/src/renderer/components/Visualiser/store/actions.js b/src/renderer/components/Visualiser/store/actions.js
index 49fd1aa09..958a3c713 100644
--- a/src/renderer/components/Visualiser/store/actions.js
+++ b/src/renderer/components/Visualiser/store/actions.js
@@ -225,9 +225,11 @@ export default {
 
       const explanation = await node.explanation();
 
-      const when = await (await explanation.getRule()).getWhen();
-      const relRegex = /(\$[^\s]*|;|{)(\s*?\(.*?\))/g;
+
       let isRelUnassigned = false;
+      const rule = await explanation.getRule();
+      const when = rule && await rule.getWhen();
+      const relRegex = /(\$[^\s]*|;|{)(\s*?\(.*?\))/g;
       let relMatches = relRegex.exec(when);
       while (relMatches) {
         if (!relMatches[1].includes('$')) {