### Added

- Allow to free buy with a negative balance
- Add parameter `$allowZero` to method `canWithdraw`

### Fixed
- method canWithdraw, with a negative price, almost always true

Author: rez1dent3

changelog.md

@@ -6,6 +6,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [3.1.2] - 2019-07-30
+### Added
+- Allow to free buy with a negative balance
+- Add parameter `$allowZero` to method `canWithdraw`
+
+### Fixed
+- method canWithdraw, with a negative price, almost always true
+
 ## [3.1.1] - 2019-07-29
 ### Added 
 - Add getCurrencyAttribute
@@ -354,7 +362,8 @@ The operation is now executed in the transaction and updates the new `refund` fi
 - Exceptions: AmountInvalid, BalanceIsEmpty.
 - Models: Transfer, Transaction.
 
-[Unreleased]: https://github.com/bavix/laravel-wallet/compare/3.1.1...HEAD
+[Unreleased]: https://github.com/bavix/laravel-wallet/compare/3.1.2...HEAD
+[3.1.2]: https://github.com/bavix/laravel-wallet/compare/3.1.1...3.1.2
 [3.1.1]: https://github.com/bavix/laravel-wallet/compare/3.1.0...3.1.1
 [3.1.0]: https://github.com/bavix/laravel-wallet/compare/3.0.4...3.1.0
 [3.0.4]: https://github.com/bavix/laravel-wallet/compare/3.0.3...3.0.4

src/Interfaces/Wallet.php

@@ -61,9 +61,10 @@ public function forceTransfer(Wallet $wallet, int $amount, ?array $meta = null):
 
     /**
      * @param int $amount
+     * @param bool $allowZero
      * @return bool
      */
-    public function canWithdraw(int $amount): bool;
+    public function canWithdraw(int $amount, bool $allowZero = null): bool;
 
     /**
      * @return int

src/Services/CommonService.php

@@ -120,11 +120,12 @@ public function deposit(Wallet $wallet, int $amount, ?array $meta, bool $confirm
     /**
      * @param Wallet $wallet
      * @param int $amount
+     * @param bool $allowZero
      * @return void
      * @throws BalanceIsEmpty
      * @throws InsufficientFunds
      */
-    public function verifyWithdraw(Wallet $wallet, int $amount): void
+    public function verifyWithdraw(Wallet $wallet, int $amount, bool $allowZero = null): void
     {
         /**
          * @var HasWallet $wallet
@@ -133,7 +134,7 @@ public function verifyWithdraw(Wallet $wallet, int $amount): void
             throw new BalanceIsEmpty(trans('wallet::errors.wallet_empty'));
         }
 
-        if (!$wallet->canWithdraw($amount)) {
+        if (!$wallet->canWithdraw($amount, $allowZero)) {
             throw new InsufficientFunds(trans('wallet::errors.insufficient_funds'));
         }
     }

src/Traits/CartPay.php

@@ -29,7 +29,7 @@ public function payFreeCart(Cart $cart): array
         }
 
         app(CommonService::class)
-            ->verifyWithdraw($this, 0);
+            ->verifyWithdraw($this, 0, true);
 
         $self = $this;
         return DB::transaction(static function() use ($self, $cart) {

src/Traits/HasWallet.php

@@ -137,10 +137,18 @@ public function withdraw(int $amount, ?array $meta = null, bool $confirmed = tru
      * Checks if you can withdraw funds
      *
      * @param int $amount
+     * @param bool $allowZero
      * @return bool
      */
-    public function canWithdraw(int $amount): bool
+    public function canWithdraw(int $amount, bool $allowZero = null): bool
     {
+        /**
+         * Allow to buy for free with a negative balance
+         */
+        if ($allowZero && $amount === 0) {
+            return true;
+        }
+
         return $this->balance >= $amount;
     }
 

tests/BalanceTest.php

@@ -27,6 +27,22 @@ public function testDepositWalletExists(): void
         $this->assertTrue($buyer->wallet->exists);
     }
 
+    /**
+     * @return void
+     */
+    public function testCanWithdraw(): void
+    {
+        /**
+         * @var Buyer $buyer
+         */
+        $buyer = factory(Buyer::class)->create();
+        $this->assertTrue($buyer->canWithdraw(0));
+
+        $buyer->forceWithdraw(1);
+        $this->assertFalse($buyer->canWithdraw(0));
+        $this->assertTrue($buyer->canWithdraw(0, true));
+    }
+
     /**
      * @return void
      */

tests/ProductTest.php

@@ -219,6 +219,32 @@ public function testPayFree(): void
         $this->assertEquals($product->balance, 0);
     }
 
+    public function testFreePay(): void
+    {
+        /**
+         * @var Buyer $buyer
+         * @var Item $product
+         */
+        $buyer = factory(Buyer::class)->create();
+        $product = factory(Item::class)->create([
+            'quantity' => 1,
+        ]);
+
+        $buyer->forceWithdraw(1000);
+        $this->assertEquals($buyer->balance, -1000);
+
+        $transfer = $buyer->payFree($product);
+        $this->assertEquals($transfer->deposit->type, Transaction::TYPE_DEPOSIT);
+        $this->assertEquals($transfer->withdraw->type, Transaction::TYPE_WITHDRAW);
+
+        $this->assertEquals($buyer->balance, -1000);
+        $this->assertEquals($product->balance, 0);
+
+        $buyer->refund($product);
+        $this->assertEquals($buyer->balance, -1000);
+        $this->assertEquals($product->balance, 0);
+    }
+
     /**
      * @return void
      */