Use spectre-build for tests

Tests/Nodes/NodeSpec.swift

@@ -9,50 +9,52 @@ class ErrorNode : NodeType {
 }
 
 
-describe("Node") {
-  let context = Context(dictionary: [
-    "name": "Kyle",
-    "age": 27,
-    "items": [1, 2, 3],
-  ])
+func testNode() {
+  describe("Node") {
+    let context = Context(dictionary: [
+      "name": "Kyle",
+      "age": 27,
+      "items": [1, 2, 3],
+    ])
 
-  $0.describe("TextNode") {
-    $0.it("renders the given text") {
-      let node = TextNode(text: "Hello World")
-      try expect(try node.render(context)) == "Hello World"
-    }
-  }
-
-  $0.describe("VariableNode") {
-    $0.it("resolves and renders the variable") {
-      let node = VariableNode(variable: Variable("name"))
-      try expect(try node.render(context)) == "Kyle"
+    $0.describe("TextNode") {
+      $0.it("renders the given text") {
+        let node = TextNode(text: "Hello World")
+        try expect(try node.render(context)) == "Hello World"
+      }
     }
 
-    $0.it("resolves and renders a non string variable") {
-      let node = VariableNode(variable: Variable("age"))
-      try expect(try node.render(context)) == "27"
-    }
-  }
+    $0.describe("VariableNode") {
+      $0.it("resolves and renders the variable") {
+        let node = VariableNode(variable: Variable("name"))
+        try expect(try node.render(context)) == "Kyle"
+      }
 
-  $0.describe("rendering nodes") {
-    $0.it("renders the nodes") {
-      let nodes: [NodeType] = [
-        TextNode(text:"Hello "),
-        VariableNode(variable: "name"),
-      ]
-
-      try expect(try renderNodes(nodes, context)) == "Hello Kyle"
+      $0.it("resolves and renders a non string variable") {
+        let node = VariableNode(variable: Variable("age"))
+        try expect(try node.render(context)) == "27"
+      }
     }
 
-    $0.it("correctly throws a nodes failure") {
-      let nodes: [NodeType] = [
-        TextNode(text:"Hello "),
-        VariableNode(variable: "name"),
-        ErrorNode(),
-      ]
+    $0.describe("rendering nodes") {
+      $0.it("renders the nodes") {
+        let nodes: [NodeType] = [
+          TextNode(text:"Hello "),
+          VariableNode(variable: "name"),
+        ]
 
-      try expect(try renderNodes(nodes, context)).toThrow(TemplateSyntaxError("Custom Error"))
+        try expect(try renderNodes(nodes, context)) == "Hello Kyle"
+      }
+
+      $0.it("correctly throws a nodes failure") {
+        let nodes: [NodeType] = [
+          TextNode(text:"Hello "),
+          VariableNode(variable: "name"),
+          ErrorNode(),
+        ]
+
+        try expect(try renderNodes(nodes, context)).toThrow(TemplateSyntaxError("Custom Error"))
+      }
     }
   }
 }