Skip non numeric value in SUMIF

MS Excel skip non numeric values also. PhpSpreadsheet used to fail on string value with: Warning: A non-numeric value encountered.

Fixes  #618

CHANGELOG.md

@@ -24,6 +24,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 
+- skip non numeric value in SUMIF - [#618](https://github.com/PHPOffice/PhpSpreadsheet/pull/618)
 - Add excel function EXACT(value1, value2) support - [#595](https://github.com/PHPOffice/PhpSpreadsheet/pull/595)
 - Support workbook view attributes for Xlsx format - [#523](https://github.com/PHPOffice/PhpSpreadsheet/issues/523)
 - Read and write hyperlink for drawing image - [#490](https://github.com/PHPOffice/PhpSpreadsheet/pull/490)

src/PhpSpreadsheet/Calculation/MathTrig.php

@@ -1222,8 +1222,10 @@ class MathTrig
             }
 
             $testCondition = '=' . $arg . $condition;
-            if (Calculation::getInstance()->_calculateFormulaValue($testCondition)) {
-                // Is it a value within our criteria
+
+            if (is_numeric($sumArgs[$key]) &&
+                Calculation::getInstance()->_calculateFormulaValue($testCondition)) {
+                // Is it a value within our criteria and only numeric can be added to the result
                 $returnValue += $sumArgs[$key];
             }
         }

tests/PhpSpreadsheetTests/Calculation/MathTrigTest.php

@@ -560,7 +560,7 @@ class MathTrigTest extends TestCase
     public function testSUMIF($expectedResult, ...$args)
     {
         $result = MathTrig::SUMIF(...$args);
-        self::assertEquals($expectedResult, $result, null, 1E-12);
+        self::assertEquals($expectedResult, $result, '', 1E-12);
     }
 
     public function providerSUMIF()

tests/data/Calculation/MathTrig/SUMIF.php

@@ -40,7 +40,7 @@ return [
             ['"text with quotes"'],
             [''],
         ],
-        '>"', // Compare to the single characater " (double quote)
+        '>"', // Compare to the single character " (double quote)
         [
             [10],
             [100],
@@ -52,10 +52,23 @@ return [
             [''],
             ['anything'],
         ],
-        '>"', // Compare to the single characater " (double quote)
+        '>"', // Compare to the single character " (double quote)
         [
             [10],
             [100],
         ],
     ],
+    [
+        10,
+        [
+            [1],
+            [2],
+        ],
+        '<>', // any content
+        [
+            ['non-numeric value'], // ignored in SUM
+            [10],
+        ],
+    ],
+
 ];