Merge pull request #177 from kylef/iterating-tuple-arrays

Iterating array of tuples with more than two values

CHANGELOG.md

@@ -12,6 +12,7 @@
 - Similar filters are suggested when unknown filter is used
 - Added `indent` filter
 - Allow using new lines inside tags
+- Added support for iterating arrays of tuples
 
 ### Bug Fixes
 

Sources/ForTag.swift

@@ -53,25 +53,26 @@ class ForNode : NodeType {
     self.where = `where`
   }
 
-  func push<Result>(value: Any, context: Context, closure: () throws -> (Result)) rethrows -> Result {
+  func push<Result>(value: Any, context: Context, closure: () throws -> (Result)) throws -> Result {
     if loopVariables.isEmpty {
       return try context.push() {
         return try closure()
       }
     }
 
-    if let value = value as? (Any, Any) {
+    let valueMirror = Mirror(reflecting: value)
-      let first = loopVariables[0]
+    if case .tuple? = valueMirror.displayStyle {
-
+      if loopVariables.count > Int(valueMirror.children.count) {
-      if loopVariables.count == 2 {
+        throw TemplateSyntaxError("Tuple '\(value)' has less values than loop variables")
-        let second = loopVariables[1]
-
-        return try context.push(dictionary: [first: value.0, second: value.1]) {
-          return try closure()
       }
+      var variablesContext = [String: Any]()
+      valueMirror.children.prefix(loopVariables.count).enumerated().forEach({ (offset, element) in
+        if loopVariables[offset] != "_" {
+          variablesContext[loopVariables[offset]] = element.value
         }
+      })
 
-      return try context.push(dictionary: [first: value.0]) {
+      return try context.push(dictionary: variablesContext) {
         return try closure()
       }
     }

Tests/StencilTests/ForNodeSpec.swift

@@ -11,7 +11,8 @@ func testForNode() {
       "dict": [
         "one": "I",
         "two": "II",
-      ]
+      ],
+      "tuples": [(1, 2, 3), (4, 5, 6)]
     ])
 
     $0.it("renders the given nodes for each item") {
@@ -127,6 +128,53 @@ func testForNode() {
       try expect(result) == fixture
     }
 
+    $0.context("given array of tuples") {
+      $0.it("can iterate over all tuple values") {
+        let templateString = "{% for first,second,third in tuples %}" +
+          "{{ first }}, {{ second }}, {{ third }}\n" +
+        "{% endfor %}\n"
+
+        let template = Template(templateString: templateString)
+        let result = try template.render(context)
+
+        let fixture = "1, 2, 3\n4, 5, 6\n\n"
+        try expect(result) == fixture
+      }
+
+      $0.it("can iterate with less number of variables") {
+        let templateString = "{% for first,second in tuples %}" +
+          "{{ first }}, {{ second }}\n" +
+        "{% endfor %}\n"
+
+        let template = Template(templateString: templateString)
+        let result = try template.render(context)
+
+        let fixture = "1, 2\n4, 5\n\n"
+        try expect(result) == fixture
+      }
+
+      $0.it("can use _ to skip variables") {
+        let templateString = "{% for first,_,third in tuples %}" +
+          "{{ first }}, {{ third }}\n" +
+        "{% endfor %}\n"
+
+        let template = Template(templateString: templateString)
+        let result = try template.render(context)
+
+        let fixture = "1, 3\n4, 6\n\n"
+        try expect(result) == fixture
+      }
+
+      $0.it("throws when number of variables is more than number of tuple values") {
+        let templateString = "{% for key,value,smth in dict %}" +
+        "{% endfor %}\n"
+
+        let template = Template(templateString: templateString)
+        try expect(template.render(context)).toThrow()
+      }
+
+    }
+
     $0.it("can iterate over dictionary") {
       let templateString = "{% for key,value in dict %}" +
         "{{ key }}: {{ value }}," +