replaced Token with Lexeme protocol on TemplateSyntaxError

Sources/Errors.swift

@@ -17,3 +17,29 @@ public class TemplateDoesNotExist: Error, CustomStringConvertible {
     return "Template named `\(templates)` does not exist. No loaders found"
   }
 }
+
+public struct TemplateSyntaxError : Error, Equatable, CustomStringConvertible {
+  public let description:String
+  var lexeme: Lexeme?
+  
+  public init(_ description:String) {
+    self.description = description
+  }
+  
+  public static func ==(lhs:TemplateSyntaxError, rhs:TemplateSyntaxError) -> Bool {
+    return lhs.description == rhs.description
+  }
+  
+}
+
+extension Range where Bound == String.Index {
+  internal static var unknown: Range {
+    return "".range
+  }
+}
+
+extension String {
+  var range: Range<String.Index> {
+    return startIndex..<endIndex
+  }
+}

Sources/Lexer.swift

@@ -53,8 +53,29 @@ struct Lexer {
 
     return tokens
   }
+  
+  func lexemeLine(_ lexeme: Lexeme) -> (content: String, number: Int, offset: String.IndexDistance) {
+    var lineNumber: Int = 0
+    var offset = 0
+    var lineContent = ""
+    
+    templateString.enumerateLines { (line, stop) in
+      lineNumber += 1
+      lineContent = line
+      if let rangeOfLine = self.templateString.range(of: line), rangeOfLine.contains(lexeme.range.lowerBound) {
+        offset = self.templateString.distance(from: rangeOfLine.lowerBound, to:
+          lexeme.range.lowerBound)
+        stop = true
+      }
+    }
+    return (lineContent, lineNumber, offset)
   }
   
+}
+
+protocol Lexeme {
+  var range: Range<String.Index> { get }
+}
 
 class Scanner {
   let _content: String //stores original content
@@ -163,20 +184,4 @@ extension String {
     return String(self[first..<last])
   }
   
-  func lineAndPosition(at range: Range<String.Index>) -> (content: String, number: Int, offset: String.IndexDistance) {
-    var lineNumber: Int = 0
-    var offset = 0
-    var lineContent = ""
-    
-    enumerateLines { (line, stop) in
-      lineNumber += 1
-      lineContent = line
-      if let rangeOfLine = self.range(of: line), rangeOfLine.contains(range.lowerBound) {
-        offset = self.distance(from: rangeOfLine.lowerBound, to: range.lowerBound)
-        stop = true
-      }
-    }
-    return (lineContent, lineNumber, offset)
-  }
-  
 }

Sources/Node.swift

@@ -1,32 +1,5 @@
 import Foundation
 
-
-public struct TemplateSyntaxError : Error, Equatable, CustomStringConvertible {
-  public let description:String
-  public var token: Token?
-
-  public init(_ description:String) {
-    self.description = description
-  }
-  
-  public func contextAwareError(templateName: String?, templateContent: String) -> TemplateSyntaxError? {
-    guard let token = token, token.range != .unknown else { return nil }
-    let templateName = templateName.map({ "\($0):" }) ?? ""
-    let (line, lineNumber, offset) = templateContent.lineAndPosition(at: token.range)
-    let tokenContent = templateContent.substring(with: token.range)
-    let highlight = "\(String(Array(repeating: " ", count: offset)))^\(String(Array(repeating: "~", count: max(tokenContent.count - 1, 0))))"
-    let description = "\(templateName)\(lineNumber):\(offset): error: " + self.description + "\n\(line)\n\(highlight)\n"
-    return TemplateSyntaxError(description)
-  }
-  
-}
-
-
-public func ==(lhs:TemplateSyntaxError, rhs:TemplateSyntaxError) -> Bool {
-  return lhs.description == rhs.description
-}
-
-
 public protocol NodeType {
   /// Render the node in the given context
   func render(_ context:Context) throws -> String

Sources/Parser.swift

@@ -53,8 +53,8 @@ public class TokenParser {
             let node = try parser(self, token)
             nodes.append(node)
           } catch {
-            if var syntaxError = error as? TemplateSyntaxError, syntaxError.token == nil {
-                syntaxError.token = token
+            if var syntaxError = error as? TemplateSyntaxError, syntaxError.lexeme == nil {
+                syntaxError.lexeme = token
                 throw syntaxError
             } else {
               throw error

Sources/Template.swift

@@ -68,17 +68,8 @@ open class Template: ExpressibleByStringLiteral {
   func render(_ context: Context) throws -> String {
     let context = context
     let parser = TokenParser(tokens: tokens, environment: context.environment)
-    do {
     let nodes = try parser.parse()
     return try renderNodes(nodes, context)
-    } catch {
-      if let syntaxError = error as? TemplateSyntaxError,
-        let error = syntaxError.contextAwareError(templateName: name, templateContent: templateString) {
-        throw error
-      } else {
-        throw error
-      }
-    }
   }
 
   /// Render the given template

Sources/Tokenizer.swift

@@ -40,19 +40,7 @@ extension String {
   }
 }
 
-extension Range where Bound == String.Index {
-  internal static var unknown: Range {
-    return "".range
-  }
-}
-
-extension String {
-  var range: Range<String.Index> {
-    return startIndex..<endIndex
-  }
-}
-
-public enum Token : Equatable {
+public enum Token : Equatable, Lexeme {
   /// A token representing a piece of text.
   case text(value: String, at: Range<String.Index>)