Merge pull request #167 from caugner/head-support

stubs/helpers.stubphp

@@ -81,6 +81,32 @@ class NullObject {
     }
 }
 
+/**
+ * Get the first element of an array. Useful for method chaining.
+ *
+ * @template TValue
+ * @template TParam of TValue[]
+ * @param  TParam  $array
+ * @return (TParam is non-empty-array ? TValue : false)
+ */
+function head($array)
+{
+    return reset($array);
+}
+
+/**
+ * Get the last element from an array.
+ *
+ * @template TValue
+ * @template TParam of TValue[]
+ * @param  TParam  $array
+ * @return (TParam is non-empty-array ? TValue : false)
+ */
+function last($array)
+{
+
+}
+
 /**
  * Provide access to optional objects.
  *

tests/acceptance/Helpers.feature

@@ -31,6 +31,38 @@ Feature: helpers
     When I run Psalm
     Then I see no errors
 
+  Scenario: head and last support
+    Given I have the following code
+    """
+        /**
+         * @return false
+         */
+        function empty_head()
+        {
+            return head([]);
+        }
+
+        /**
+         * @return false
+         */
+        function empty_last()
+        {
+            return last([]);
+        }
+
+        function non_empty_head(): int
+        {
+            return last([1, 2, 3]);
+        }
+
+        function non_empty_last(): int
+        {
+            return last([1, 2, 3]);
+        }
+    """
+    When I run Psalm
+    Then I see no errors
+
   Scenario: optional support
     Given I have the following code
     """
@@ -38,7 +70,6 @@ Feature: helpers
         {
             return optional($user)->getMessage();
         }
-
     """
     When I run Psalm
     Then I see no errors
@@ -58,7 +89,6 @@ Feature: helpers
         {
           return logger();
         }
-
     """
     When I run Psalm
     Then I see no errors