fix InvoiceItem.UnitPrice type (#849)

It's a string, not a float. A float makes sense, but I only get strings
back on the wire.

Fixes #848

Signed-off-by: Jordan Whited <[email protected]>
Co-authored-by: Zhiwei Liang <[email protected]>

Author: jwhited

account_invoices.go

@@ -29,7 +29,7 @@ type InvoiceTaxSummary struct {
 type InvoiceItem struct {
 	Label     string     `json:"label"`
 	Type      string     `json:"type"`
-	UnitPrice float32    `json:"unit_price"`
+	UnitPrice string     `json:"unit_price"`
 	Quantity  int        `json:"quantity"`
 	Amount    float32    `json:"amount"`
 	Tax       float32    `json:"tax"`

test/unit/account_invoices_test.go

@@ -83,5 +83,5 @@ func TestAccountInvoiceItems_List(t *testing.T) {
 	assert.Equal(t, float32(1.25), invoiceItem.Tax)
 	assert.Equal(t, float32(21.45), invoiceItem.Total)
 	assert.Equal(t, "hourly", invoiceItem.Type)
-	assert.Equal(t, float32(5.05), invoiceItem.UnitPrice)
+	assert.Equal(t, "5.05", invoiceItem.UnitPrice)
 }

test/unit/fixtures/account_invoice_items_list.json

@@ -10,7 +10,7 @@
       "to": "2018-01-31T11:59:59",
       "total": 21.45,
       "type": "hourly",
-      "unit_price": 5.05
+      "unit_price": "5.05"
     }
   ],
   "page": 1,