From 4bb042c3525b93f961216bd97851ee54e932a951 Mon Sep 17 00:00:00 2001
From: Marina Glancy <marina@moodle.com>
Date: Tue, 2 Aug 2022 18:26:37 +0200
Subject: [PATCH] MDL-75358 reportbuilder: display nulls as empty cells in
 aggregation

---
 reportbuilder/classes/local/aggregation/avg.php                | 3 +++
 reportbuilder/classes/local/aggregation/groupconcat.php        | 7 ++++++-
 reportbuilder/classes/local/aggregation/percent.php            | 3 +++
 reportbuilder/classes/local/aggregation/sum.php                | 6 +++++-
 reportbuilder/tests/local/helpers/user_profile_fields_test.php | 2 +-
 5 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/reportbuilder/classes/local/aggregation/avg.php b/reportbuilder/classes/local/aggregation/avg.php
index 26d02751e66..c397640ecf6 100644
--- a/reportbuilder/classes/local/aggregation/avg.php
+++ b/reportbuilder/classes/local/aggregation/avg.php
@@ -76,6 +76,9 @@ class avg extends base {
      * @return mixed
      */
     public static function format_value($value, array $values, array $callbacks, int $columntype) {
+        if (reset($values) === null) {
+            return null;
+        }
         if ($columntype === column::TYPE_BOOLEAN || empty($callbacks)) {
             return format_float((float) reset($values), 1);
         }
diff --git a/reportbuilder/classes/local/aggregation/groupconcat.php b/reportbuilder/classes/local/aggregation/groupconcat.php
index 4cd07b47aba..7c12591c8ef 100644
--- a/reportbuilder/classes/local/aggregation/groupconcat.php
+++ b/reportbuilder/classes/local/aggregation/groupconcat.php
@@ -111,6 +111,11 @@ class groupconcat extends base {
      * @return mixed
      */
     public static function format_value($value, array $values, array $callbacks, int $columntype) {
+        $firstvalue = reset($values);
+        if ($firstvalue === null) {
+            return '';
+        }
+
         $formattedvalues = [];
 
         // Store original names of all values that would be present without aggregation.
@@ -118,7 +123,7 @@ class groupconcat extends base {
         $valuenamescount = count($valuenames);
 
         // Loop over each extracted value from the concatenated string.
-        $values = explode(self::FIELD_VALUE_DELIMETER, (string) reset($values));
+        $values = explode(self::FIELD_VALUE_DELIMETER, (string)$firstvalue);
         foreach ($values as $value) {
 
             // Ensure we have equal number of value names/data, account for truncation by DB.
diff --git a/reportbuilder/classes/local/aggregation/percent.php b/reportbuilder/classes/local/aggregation/percent.php
index de10bfa00d0..3d052fcfff4 100644
--- a/reportbuilder/classes/local/aggregation/percent.php
+++ b/reportbuilder/classes/local/aggregation/percent.php
@@ -73,6 +73,9 @@ class percent extends base {
      * @return string
      */
     public static function format_value($value, array $values, array $callbacks, int $columntype): string {
+        if (reset($values) === null) {
+            return '';
+        }
         return format::percent((float) reset($values));
     }
 }
diff --git a/reportbuilder/classes/local/aggregation/sum.php b/reportbuilder/classes/local/aggregation/sum.php
index ea7d547f409..42b1a91c206 100644
--- a/reportbuilder/classes/local/aggregation/sum.php
+++ b/reportbuilder/classes/local/aggregation/sum.php
@@ -76,9 +76,13 @@ class sum extends base {
      * @return mixed
      */
     public static function format_value($value, array $values, array $callbacks, int $columntype) {
+        $firstvalue = reset($values);
+        if ($firstvalue === null) {
+            return null;
+        }
         if ($columntype === column::TYPE_BOOLEAN || empty($callbacks)) {
             $decimalpoints = (int) ($columntype === column::TYPE_FLOAT);
-            return format_float((float) reset($values), $decimalpoints);
+            return format_float((float) $firstvalue, $decimalpoints);
         }
 
         return parent::format_value($value, $values, $callbacks, $columntype);
diff --git a/reportbuilder/tests/local/helpers/user_profile_fields_test.php b/reportbuilder/tests/local/helpers/user_profile_fields_test.php
index 4cbe2f2725e..5b7d1480ce4 100644
--- a/reportbuilder/tests/local/helpers/user_profile_fields_test.php
+++ b/reportbuilder/tests/local/helpers/user_profile_fields_test.php
@@ -206,7 +206,7 @@ class user_profile_fields_test extends core_reportbuilder_testcase {
         $this->assertEquals([
             [
                 'c0_firstname' => 'Admin',
-                'c1_data' => 'No',
+                'c1_data' => '',
                 'c2_data' => 'Not set',
                 'c3_data' => '',
                 'c4_data' => '',
-- 
2.11.4.GIT