From 1223efbc7e4585b760d4ae538a5838199793f6ca Mon Sep 17 00:00:00 2001
From: Ilya Puchka <ilyapuchka@gmail.com>
Date: Sun, 24 Dec 2017 20:11:46 +0100
Subject: [PATCH] fix(default): Check for wrapped nil in filter (#162)

---
 CHANGELOG.md                        | 1 +
 Sources/Filters.swift               | 3 ++-
 Tests/StencilTests/FilterSpec.swift | 8 ++++++++
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9551785d..fd8e81f8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@
 ### Bug Fixes
 
 - Fixed rendering `{{ block.super }}` with several levels of inheritance
+- Fixed checking dictionary values for nil in `default` filter
 
 
 ## 0.10.1
diff --git a/Sources/Filters.swift b/Sources/Filters.swift
index dd78ff42..f84a5341 100644
--- a/Sources/Filters.swift
+++ b/Sources/Filters.swift
@@ -11,7 +11,8 @@ func lowercase(_ value: Any?) -> Any? {
 }
 
 func defaultFilter(value: Any?, arguments: [Any?]) -> Any? {
-  if let value = value {
+  // value can be optional wrapping nil, so this way we check for underlying value
+  if let value = value, String(describing: value) != "nil" {
     return value
   }
 
diff --git a/Tests/StencilTests/FilterSpec.swift b/Tests/StencilTests/FilterSpec.swift
index 61e2dda8..ded572c0 100644
--- a/Tests/StencilTests/FilterSpec.swift
+++ b/Tests/StencilTests/FilterSpec.swift
@@ -136,6 +136,14 @@ func testFilter() {
       let result = try template.render(Context(dictionary: [:]))
       try expect(result) == "Hello World"
     }
+    
+    $0.it("checks for underlying nil value correctly") {
+      let template = Template(templateString: "Hello {{ user.name|default:\"anonymous\" }}")
+      let nilName: String? = nil
+      let user: [String: Any?] = ["name": nilName]
+      let result = try template.render(Context(dictionary: ["user": user]))
+      try expect(result) == "Hello anonymous"
+    }
   }
 
   describe("join filter") {