Merge pull request #13 from gear4s/feature/valid-null-sql-generation

Add support for valid NULL queries

Author: aglipanci

src/Query/CaseBuilder.php

@@ -82,16 +82,30 @@ public function when($column, $operator = null, $value = null): self
             func_num_args() === 2
         );
 
-        if ($value) {
-            $this->whens[] = $this->grammar->wrapColumn($column) . ' ' . $operator . ' ?';
-
+        if (isset($value)) {
             $this->addBinding($value, 'when');
-        } elseif ($operator) {
-            $this->whens[] = $this->grammar->wrapColumn($column) . ' ?';
 
+            $this->whens[] = [
+                'query' => $this->grammar->wrapColumn($column) . ' ' . $operator . ' ?',
+                'binding' => count($this->bindings['when']) - 1,
+            ];
+        } elseif (is_null($value)) {
+            $operator = $operator === '=' ? 'IS' : 'IS NOT';
+
+            $this->whens[] = [
+                'query' => $this->grammar->wrapColumn($column) . ' ' . $operator . ' NULL',
+            ];
+        } elseif ($operator) {
             $this->addBinding($operator, 'when');
+
+            $this->whens[] = [
+                'query' => $this->grammar->wrapColumn($column) . ' ?',
+                'binding' => count($this->bindings['when']) - 1,
+            ];
         } else {
-            $this->whens[] = $column;
+            $this->whens[] = [
+                'query' => $column,
+            ];
         }
 
         return $this;
@@ -107,10 +121,13 @@ public function whenRaw(string $expression, $bindings = []): self
             CaseBuilderException::wrongWhenPosition()
         );
 
-        $this->whens[] = $expression;
-
         $this->addBinding($bindings, 'when');
 
+        $this->whens[] = [
+            'query' => $expression,
+            'binding' => count($this->bindings['when']) - 1,
+        ];
+
         return $this;
     }
 
@@ -124,10 +141,10 @@ public function then($value): self
             CaseBuilderException::thenCannotBeBeforeWhen()
         );
 
-        $this->thens[] = '?';
-
         $this->addBinding($value, 'then');
 
+        $this->thens[] = '?';
+
         return $this;
     }
 
@@ -256,10 +273,12 @@ public function getBindings(): array
          * Flattening here is to handle raw cases with multiple bindings.
          */
         foreach ($this->whens as $i => $when) {
-            if (is_array($this->bindings['when'][$i])) {
-                $bindings = array_merge($bindings, $this->bindings['when'][$i]);
-            } else {
-                $bindings[] = $this->bindings['when'][$i];
+            if (array_key_exists('binding', $when)) {
+                if (is_array($this->bindings['when'][$when['binding']])) {
+                    $bindings = array_merge($bindings, $this->bindings['when'][$when['binding']]);
+                } else {
+                    $bindings[] = $this->bindings['when'][$when['binding']];
+                }
             }
 
             if (is_array($this->bindings['then'][$i])) {

src/Query/Grammar.php

@@ -17,7 +17,7 @@ public function compile(CaseBuilder $caseBuilder): string
 
         foreach ($caseBuilder->whens as $i => $when) {
             $components[] = 'when';
-            $components[] = $when;
+            $components[] = $when['query'];
             $components[] = 'then';
             $components[] = $caseBuilder->thens[$i];
         }

tests/CaseBuilderTest.php

@@ -52,6 +52,30 @@ public function testCanGenerateComplexQuery()
         $this->assertCount(7, $caseQuery->getBindings());
         $this->assertEquals('case when `payment_status` = 1 then "Paid" when `payment_status` = 2 then "Due" when `payment_status` <= 5 then "Canceled" else "Unknown" end', $caseQuery->toRaw());
     }
+  
+  public function testCanGenerateComplexQueryWithNullishTypes()
+    {
+        /**
+         * @var QueryCaseBuilder $caseQuery
+         */
+        $caseQuery = CaseBuilder::when('payment_date', '>', 0)
+            ->then('Paid')
+            ->when('payment_date', 0)
+            ->then('Due')
+            ->when('payment_date', null)
+            ->then('Canceled')
+            ->else('Unknown');
+
+        $this->assertCount(3, $caseQuery->whens);
+        $this->assertCount(3, $caseQuery->thens);
+        $this->assertSameSize($caseQuery->whens, $caseQuery->thens);
+        $this->assertNotEmpty($caseQuery->else);
+
+        $this->assertEquals('case when `payment_date` > ? then ? when `payment_date` = ? then ? when `payment_date` IS NULL then ? else ? end', $caseQuery->toSql());
+        $this->assertEquals([ 0, "Paid", 0, "Due", "Canceled", "Unknown" ], $caseQuery->getBindings());
+        $this->assertCount(6, $caseQuery->getBindings());
+        $this->assertEquals('case when `payment_date` > 0 then "Paid" when `payment_date` = 0 then "Due" when `payment_date` IS NULL then "Canceled" else "Unknown" end', $caseQuery->toRaw());
+    }
 
     public function testCanGenerateComplexQueryWithDotSeparatedColumns()
     {