Allow node parsing to return an error

Closes #5
This commit is contained in:
Kyle Fuller
2014-10-26 12:11:40 +00:00
parent aad8a1884c
commit 925c663555
5 changed files with 97 additions and 43 deletions

View File

@@ -84,8 +84,8 @@ public class VariableNode : Node {
}
public class NowNode : Node {
public class func parse(parser:TokenParser, token:Token) -> Node {
return NowNode()
public class func parse(parser:TokenParser, token:Token) -> (node:Node?, error:Error?) {
return (NowNode(), nil)
}
public func render(context: Context) -> (String?, Error?) {
@@ -99,29 +99,41 @@ public class ForNode : Node {
let loopVariable:String
let nodes:[Node]
public class func parse(parser:TokenParser, token:Token) -> Node {
public class func parse(parser:TokenParser, token:Token) -> (node:Node?, error:Error?) {
let components = token.components()
let count = countElements(components)
if count == 4 && components[2] == "in" {
let loopVariable = components[1]
let variable = components[3]
let nodes = parser.parse(until(["endfor", "empty"]))
let (nodes, error) = parser.parse(until(["endfor", "empty"]))
var emptyNodes = [Node]()
if let error = error {
return (nil, error)
}
if let token = parser.nextToken() {
if token.contents == "empty" {
emptyNodes = parser.parse(until(["endfor"]))
let (nodes, error) = parser.parse(until(["endfor"]))
parser.nextToken()
if let error = error {
return (nil, error)
}
if let nodes = nodes {
emptyNodes = nodes
}
}
}
return ForNode(variable: variable, loopVariable: loopVariable, nodes: nodes, emptyNodes:emptyNodes)
return (ForNode(variable: variable, loopVariable: loopVariable, nodes: nodes!, emptyNodes:emptyNodes), nil)
} else {
// TODO error
}
return TextNode(text: "TODO return some error")
return (TextNode(text: "TODO return some error"), nil)
}
public init(variable:String, loopVariable:String, nodes:[Node], emptyNodes:[Node]) {
@@ -160,36 +172,59 @@ public class IfNode : Node {
public let trueNodes:[Node]
public let falseNodes:[Node]
public class func parse(parser:TokenParser, token:Token) -> Node {
public class func parse(parser:TokenParser, token:Token) -> (node:Node?, error:Error?) {
let variable = token.components()[1]
let trueNodes = parser.parse(until(["endif", "else"]))
let (trueNodes, error) = parser.parse(until(["endif", "else"]))
if let error = error {
return (nil, error)
}
var falseNodes = [Node]()
if let token = parser.nextToken() {
if token.contents == "else" {
falseNodes = parser.parse(until(["endif"]))
let (nodes, error) = parser.parse(until(["endif"]))
parser.nextToken()
if let error = error {
return (nil, error)
}
if let nodes = nodes {
falseNodes = nodes
}
}
}
return IfNode(variable: variable, trueNodes: trueNodes, falseNodes: falseNodes)
return (IfNode(variable: variable, trueNodes: trueNodes!, falseNodes: falseNodes), nil)
}
public class func parse_ifnot(parser:TokenParser, token:Token) -> Node {
public class func parse_ifnot(parser:TokenParser, token:Token) -> (node:Node?, error:Error?) {
let variable = token.components()[1]
let falseNodes = parser.parse(until(["endif", "else"]))
let (falseNodes, error) = parser.parse(until(["endif", "else"]))
if let error = error {
return (nil, error)
}
var trueNodes = [Node]()
if let token = parser.nextToken() {
if token.contents == "else" {
trueNodes = parser.parse(until(["endif"]))
let (nodes, error) = parser.parse(until(["endif"]))
if let error = error {
return (nil, error)
}
if let nodes = nodes {
trueNodes = nodes
}
parser.nextToken()
}
}
return IfNode(variable: variable, trueNodes: trueNodes, falseNodes: falseNodes)
return (IfNode(variable: variable, trueNodes: trueNodes, falseNodes: falseNodes!), nil)
}
public init(variable:String, trueNodes:[Node], falseNodes:[Node]) {

View File

@@ -22,7 +22,7 @@ public func until(tags:[String])(parser:TokenParser, token:Token) -> Bool {
public class TokenParser {
private var tokens:[Token]
private var tags = Dictionary<String, ((TokenParser, Token) -> (Node))>()
private var tags = Dictionary<String, ((TokenParser, Token) -> ((node:Node?, error:Error?)))>()
public init(tokens:[Token]) {
self.tokens = tokens
@@ -32,11 +32,11 @@ public class TokenParser {
tags["ifnot"] = IfNode.parse_ifnot
}
public func parse() -> [Node] {
public func parse() -> (nodes:[Node]?, error:Error?) {
return parse(nil)
}
public func parse(parse_until:((parser:TokenParser, token:Token) -> (Bool))?) -> [Node] {
public func parse(parse_until:((parser:TokenParser, token:Token) -> (Bool))?) -> (nodes:[Node]?, error:Error?) {
var nodes = [Node]()
while tokens.count > 0 {
@@ -53,14 +53,21 @@ public class TokenParser {
if let parse_until = parse_until {
if parse_until(parser: self, token: token) {
prependToken(token)
return nodes
return (nodes, nil)
}
}
if let tag = tag {
if let parser = self.tags[tag] {
let node = parser(self, token)
nodes.append(node)
let (node, error) = parser(self, token)
if let error = error {
return (nil, error)
}
if let node = node {
nodes.append(node)
}
}
}
case .Comment(let value):
@@ -68,7 +75,7 @@ public class TokenParser {
}
}
return nodes
return (nodes, nil)
}
public func nextToken() -> Token? {

View File

@@ -9,7 +9,7 @@
import Foundation
public class Template {
let nodes:[Node]
let parser:TokenParser
public convenience init(named:String) {
self.init(named:named, inBundle:nil)
@@ -36,11 +36,18 @@ public class Template {
public init(templateString:String) {
let lexer = Lexer(templateString: templateString)
let tokens = lexer.tokenize()
let parser = TokenParser(tokens: tokens)
nodes = parser.parse()
parser = TokenParser(tokens: tokens)
}
public func render(context:Context) -> (string:String?, error:Error?) {
return renderNodes(nodes, context)
let (nodes, error) = parser.parse()
if let error = error {
return (nil, error)
} else if let nodes = nodes {
return renderNodes(nodes, context)
}
return (nil, nil)
}
}

View File

@@ -101,12 +101,13 @@ class IfNodeTests: NodeTests {
]
let parser = TokenParser(tokens: tokens)
let nodes = parser.parse()
let node = nodes.first! as IfNode
let (nodes, error) = parser.parse()
let node = nodes!.first! as IfNode
let trueNode = node.trueNodes.first! as TextNode
let falseNode = node.falseNodes.first! as TextNode
XCTAssertEqual(nodes.count, 1)
XCTAssertTrue(error == nil)
XCTAssertEqual(nodes!.count, 1)
XCTAssertEqual(node.variable.variable, "value")
XCTAssertEqual(node.trueNodes.count, 1)
XCTAssertEqual(trueNode.text, "true")
@@ -124,12 +125,13 @@ class IfNodeTests: NodeTests {
]
let parser = TokenParser(tokens: tokens)
let nodes = parser.parse()
let node = nodes.first! as IfNode
let (nodes, error) = parser.parse()
let node = nodes!.first! as IfNode
let trueNode = node.trueNodes.first! as TextNode
let falseNode = node.falseNodes.first! as TextNode
XCTAssertEqual(nodes.count, 1)
XCTAssertTrue(error == nil)
XCTAssertEqual(nodes!.count, 1)
XCTAssertEqual(node.variable.variable, "value")
XCTAssertEqual(node.trueNodes.count, 1)
XCTAssertEqual(trueNode.text, "true")

View File

@@ -16,10 +16,11 @@ class TokenParserTests: XCTestCase {
Token.Text(value: "Hello World")
])
let nodes = parser.parse()
let node = nodes.first as TextNode!
let (nodes, error) = parser.parse()
let node = nodes!.first as TextNode!
XCTAssertEqual(nodes.count, 1)
XCTAssertTrue(error == nil)
XCTAssertEqual(nodes!.count, 1)
XCTAssertEqual(node.text, "Hello World")
}
@@ -28,11 +29,12 @@ class TokenParserTests: XCTestCase {
Token.Variable(value: "name")
])
let nodes = parser.parse()
let node = nodes.first as VariableNode!
let (nodes, error) = parser.parse()
let node = nodes!.first as VariableNode!
let variable = node.variable
XCTAssertEqual(nodes.count, 1)
XCTAssertTrue(error == nil)
XCTAssertEqual(nodes!.count, 1)
XCTAssertEqual(variable, Variable("name"))
}
@@ -41,9 +43,9 @@ class TokenParserTests: XCTestCase {
Token.Comment(value: "Secret stuff!")
])
let nodes = parser.parse()
let (nodes, error) = parser.parse()
XCTAssertEqual(nodes.count, 0)
XCTAssertEqual(nodes!.count, 0)
}
func testParsingTagToken() {
@@ -51,8 +53,9 @@ class TokenParserTests: XCTestCase {
Token.Block(value: "now"),
])
let nodes = parser.parse()
let node = nodes.first as NowNode!
XCTAssertEqual(nodes.count, 1)
let (nodes, error) = parser.parse()
let node = nodes!.first as NowNode!
XCTAssertTrue(error == nil)
XCTAssertEqual(nodes!.count, 1)
}
}