349 lines
15 KiB
Swift
349 lines
15 KiB
Swift
|
|
extension HBMustacheTemplate {
|
|
/// Error return by `HBMustacheTemplate.parse`. Includes information about where error occurred
|
|
public struct ParserError: Swift.Error {
|
|
public let context: HBParser.Context
|
|
public let error: Swift.Error
|
|
}
|
|
|
|
/// Error generated by `HBMustacheTemplate.parse`
|
|
public enum Error: Swift.Error {
|
|
/// the end section does not match the name of the start section
|
|
case sectionCloseNameIncorrect
|
|
/// tag was badly formatted
|
|
case unfinishedName
|
|
/// was not expecting a section end
|
|
case expectedSectionEnd
|
|
/// set delimiter tag badly formatted
|
|
case invalidSetDelimiter
|
|
/// cannot apply transform to inherited section
|
|
case transformAppliedToInheritanceSection
|
|
/// illegal token inside inherit section of partial
|
|
case illegalTokenInsideInheritSection
|
|
/// text found inside inherit section of partial
|
|
case textInsideInheritSection
|
|
}
|
|
|
|
struct ParserState {
|
|
var sectionName: String?
|
|
var sectionTransform: String?
|
|
var newLine: Bool
|
|
var startDelimiter: String
|
|
var endDelimiter: String
|
|
|
|
init() {
|
|
self.sectionName = nil
|
|
self.newLine = true
|
|
self.startDelimiter = "{{"
|
|
self.endDelimiter = "}}"
|
|
}
|
|
|
|
func withSectionName(_ name: String, transform: String? = nil) -> ParserState {
|
|
var newValue = self
|
|
newValue.sectionName = name
|
|
newValue.sectionTransform = transform
|
|
return newValue
|
|
}
|
|
|
|
func withDelimiters(start: String, end: String) -> ParserState {
|
|
var newValue = self
|
|
newValue.startDelimiter = start
|
|
newValue.endDelimiter = end
|
|
return newValue
|
|
}
|
|
|
|
func withDefaultDelimiters(start _: String, end _: String) -> ParserState {
|
|
var newValue = self
|
|
newValue.startDelimiter = "{{"
|
|
newValue.endDelimiter = "}}"
|
|
return newValue
|
|
}
|
|
}
|
|
|
|
/// parse mustache text to generate a list of tokens
|
|
static func parse(_ string: String) throws -> [Token] {
|
|
var parser = HBParser(string)
|
|
do {
|
|
return try self.parse(&parser, state: .init())
|
|
} catch {
|
|
throw ParserError(context: parser.getContext(), error: error)
|
|
}
|
|
}
|
|
|
|
/// parse section in mustache text
|
|
static func parse(_ parser: inout HBParser, state: ParserState) throws -> [Token] {
|
|
var tokens: [Token] = []
|
|
var state = state
|
|
var whiteSpaceBefore: Substring = ""
|
|
while !parser.reachedEnd() {
|
|
// if new line read whitespace
|
|
if state.newLine {
|
|
whiteSpaceBefore = parser.read(while: Set(" \t"))
|
|
}
|
|
let text = try readUntilDelimiterOrNewline(&parser, state: state)
|
|
// if we hit a newline add text
|
|
if parser.current().isNewline {
|
|
tokens.append(.text(whiteSpaceBefore + text + String(parser.current())))
|
|
state.newLine = true
|
|
parser.unsafeAdvance()
|
|
continue
|
|
}
|
|
// we have found a tag
|
|
// whatever text we found before the tag should be added as a token
|
|
if text.count > 0 {
|
|
tokens.append(.text(whiteSpaceBefore + text))
|
|
whiteSpaceBefore = ""
|
|
state.newLine = false
|
|
}
|
|
// have we reached the end of the text
|
|
if parser.reachedEnd() {
|
|
break
|
|
}
|
|
var setNewLine = false
|
|
switch parser.current() {
|
|
case "#":
|
|
// section
|
|
parser.unsafeAdvance()
|
|
let (name, transform) = try parseName(&parser, state: state)
|
|
if self.isStandalone(&parser, state: state) {
|
|
setNewLine = true
|
|
} else if whiteSpaceBefore.count > 0 {
|
|
tokens.append(.text(String(whiteSpaceBefore)))
|
|
whiteSpaceBefore = ""
|
|
}
|
|
let sectionTokens = try parse(&parser, state: state.withSectionName(name, transform: transform))
|
|
tokens.append(.section(name: name, transform: transform, template: HBMustacheTemplate(sectionTokens)))
|
|
|
|
case "^":
|
|
// inverted section
|
|
parser.unsafeAdvance()
|
|
let (name, transform) = try parseName(&parser, state: state)
|
|
if self.isStandalone(&parser, state: state) {
|
|
setNewLine = true
|
|
} else if whiteSpaceBefore.count > 0 {
|
|
tokens.append(.text(String(whiteSpaceBefore)))
|
|
whiteSpaceBefore = ""
|
|
}
|
|
let sectionTokens = try parse(&parser, state: state.withSectionName(name, transform: transform))
|
|
tokens.append(.invertedSection(name: name, transform: transform, template: HBMustacheTemplate(sectionTokens)))
|
|
|
|
case "$":
|
|
// inherited section
|
|
parser.unsafeAdvance()
|
|
let (name, transform) = try parseName(&parser, state: state)
|
|
// ERROR: can't have transform applied to inherited sections
|
|
guard transform == nil else { throw Error.transformAppliedToInheritanceSection }
|
|
if self.isStandalone(&parser, state: state) {
|
|
setNewLine = true
|
|
} else if whiteSpaceBefore.count > 0 {
|
|
tokens.append(.text(String(whiteSpaceBefore)))
|
|
whiteSpaceBefore = ""
|
|
}
|
|
let sectionTokens = try parse(&parser, state: state.withSectionName(name, transform: transform))
|
|
tokens.append(.inheritedSection(name: name, template: HBMustacheTemplate(sectionTokens)))
|
|
|
|
case "/":
|
|
// end of section
|
|
parser.unsafeAdvance()
|
|
let position = parser.position
|
|
let (name, transform) = try parseName(&parser, state: state)
|
|
guard name == state.sectionName, transform == state.sectionTransform else {
|
|
parser.unsafeSetPosition(position)
|
|
throw Error.sectionCloseNameIncorrect
|
|
}
|
|
if self.isStandalone(&parser, state: state) {
|
|
setNewLine = true
|
|
} else if whiteSpaceBefore.count > 0 {
|
|
tokens.append(.text(String(whiteSpaceBefore)))
|
|
whiteSpaceBefore = ""
|
|
}
|
|
return tokens
|
|
|
|
case "!":
|
|
// comment
|
|
parser.unsafeAdvance()
|
|
_ = try self.parseComment(&parser, state: state)
|
|
setNewLine = self.isStandalone(&parser, state: state)
|
|
|
|
case "{":
|
|
// unescaped variable
|
|
if whiteSpaceBefore.count > 0 {
|
|
tokens.append(.text(String(whiteSpaceBefore)))
|
|
whiteSpaceBefore = ""
|
|
}
|
|
parser.unsafeAdvance()
|
|
let (name, transform) = try parseName(&parser, state: state)
|
|
guard try parser.read("}") else { throw Error.unfinishedName }
|
|
tokens.append(.unescapedVariable(name: name, transform: transform))
|
|
|
|
case "&":
|
|
// unescaped variable
|
|
if whiteSpaceBefore.count > 0 {
|
|
tokens.append(.text(String(whiteSpaceBefore)))
|
|
whiteSpaceBefore = ""
|
|
}
|
|
parser.unsafeAdvance()
|
|
let (name, transform) = try parseName(&parser, state: state)
|
|
tokens.append(.unescapedVariable(name: name, transform: transform))
|
|
|
|
case ">":
|
|
// partial
|
|
parser.unsafeAdvance()
|
|
let (name, _) = try parseName(&parser, state: state)
|
|
if whiteSpaceBefore.count > 0 {
|
|
tokens.append(.text(String(whiteSpaceBefore)))
|
|
}
|
|
if self.isStandalone(&parser, state: state) {
|
|
setNewLine = true
|
|
tokens.append(.partial(name, indentation: String(whiteSpaceBefore), inherits: nil))
|
|
} else {
|
|
tokens.append(.partial(name, indentation: nil, inherits: nil))
|
|
}
|
|
whiteSpaceBefore = ""
|
|
|
|
case "<":
|
|
// partial with inheritance
|
|
parser.unsafeAdvance()
|
|
let (name, transform) = try parseName(&parser, state: state)
|
|
// ERROR: can't have transform applied to inherited sections
|
|
guard transform == nil else { throw Error.transformAppliedToInheritanceSection }
|
|
var indent: String?
|
|
if self.isStandalone(&parser, state: state) {
|
|
setNewLine = true
|
|
} else if whiteSpaceBefore.count > 0 {
|
|
indent = String(whiteSpaceBefore)
|
|
tokens.append(.text(indent!))
|
|
whiteSpaceBefore = ""
|
|
}
|
|
let sectionTokens = try parse(&parser, state: state.withSectionName(name, transform: transform))
|
|
var inherit: [String: HBMustacheTemplate] = [:]
|
|
// parse tokens in section to extract inherited sections
|
|
for token in sectionTokens {
|
|
switch token {
|
|
case .inheritedSection(let name, let template):
|
|
inherit[name] = template
|
|
case .text:
|
|
break
|
|
default:
|
|
throw Error.illegalTokenInsideInheritSection
|
|
}
|
|
}
|
|
tokens.append(.partial(name, indentation: indent, inherits: inherit))
|
|
|
|
case "=":
|
|
// set delimiter
|
|
parser.unsafeAdvance()
|
|
state = try self.parserSetDelimiter(&parser, state: state)
|
|
setNewLine = self.isStandalone(&parser, state: state)
|
|
|
|
default:
|
|
// variable
|
|
if whiteSpaceBefore.count > 0 {
|
|
tokens.append(.text(String(whiteSpaceBefore)))
|
|
whiteSpaceBefore = ""
|
|
}
|
|
let (name, transform) = try parseName(&parser, state: state)
|
|
tokens.append(.variable(name: name, transform: transform))
|
|
}
|
|
state.newLine = setNewLine
|
|
}
|
|
// should never get here if reading section
|
|
guard state.sectionName == nil else {
|
|
throw Error.expectedSectionEnd
|
|
}
|
|
return tokens
|
|
}
|
|
|
|
/// read until we hit either the start delimiter of a tag or a newline
|
|
static func readUntilDelimiterOrNewline(_ parser: inout HBParser, state: ParserState) throws -> String {
|
|
var untilSet: Set<Character> = ["\n", "\r\n"]
|
|
guard let delimiterFirstChar = state.startDelimiter.first else { return "" }
|
|
var totalText = ""
|
|
untilSet.insert(delimiterFirstChar)
|
|
|
|
while !parser.reachedEnd() {
|
|
// read until we hit either a newline or "{"
|
|
let text = try parser.read(until: untilSet, throwOnOverflow: false)
|
|
totalText += text
|
|
// if new line append all text read plus newline
|
|
if parser.current().isNewline {
|
|
break
|
|
} else if parser.current() == delimiterFirstChar {
|
|
if try parser.read(string: state.startDelimiter) {
|
|
break
|
|
}
|
|
totalText += String(delimiterFirstChar)
|
|
parser.unsafeAdvance()
|
|
}
|
|
}
|
|
return totalText
|
|
}
|
|
|
|
/// parse variable name
|
|
static func parseName(_ parser: inout HBParser, state: ParserState) throws -> (String, String?) {
|
|
parser.read(while: \.isWhitespace)
|
|
let text = String(parser.read(while: self.sectionNameChars))
|
|
parser.read(while: \.isWhitespace)
|
|
guard try parser.read(string: state.endDelimiter) else { throw Error.unfinishedName }
|
|
|
|
// does the name include brackets. If so this is a transform call
|
|
var nameParser = HBParser(String(text))
|
|
let string = nameParser.read(while: self.sectionNameCharsWithoutBrackets)
|
|
if nameParser.reachedEnd() {
|
|
return (text, nil)
|
|
} else {
|
|
// parse function parameter, as we have just parsed a function name
|
|
guard nameParser.current() == "(" else { throw Error.unfinishedName }
|
|
nameParser.unsafeAdvance()
|
|
let string2 = nameParser.read(while: self.sectionNameCharsWithoutBrackets)
|
|
guard nameParser.current() == ")" else { throw Error.unfinishedName }
|
|
nameParser.unsafeAdvance()
|
|
guard nameParser.reachedEnd() else { throw Error.unfinishedName }
|
|
return (String(string2), String(string))
|
|
}
|
|
}
|
|
|
|
static func parseComment(_ parser: inout HBParser, state: ParserState) throws -> String {
|
|
let text = try parser.read(untilString: state.endDelimiter, throwOnOverflow: true, skipToEnd: true)
|
|
return String(text)
|
|
}
|
|
|
|
static func parserSetDelimiter(_ parser: inout HBParser, state: ParserState) throws -> ParserState {
|
|
let startDelimiter: Substring
|
|
let endDelimiter: Substring
|
|
|
|
do {
|
|
parser.read(while: \.isWhitespace)
|
|
startDelimiter = try parser.read(until: \.isWhitespace)
|
|
parser.read(while: \.isWhitespace)
|
|
endDelimiter = try parser.read(until: { $0 == "=" || $0.isWhitespace })
|
|
parser.read(while: \.isWhitespace)
|
|
} catch {
|
|
throw Error.invalidSetDelimiter
|
|
}
|
|
guard try parser.read("=") else { throw Error.invalidSetDelimiter }
|
|
guard try parser.read(string: state.endDelimiter) else { throw Error.invalidSetDelimiter }
|
|
guard startDelimiter.count > 0, endDelimiter.count > 0 else { throw Error.invalidSetDelimiter }
|
|
return state.withDelimiters(start: String(startDelimiter), end: String(endDelimiter))
|
|
}
|
|
|
|
static func hasLineFinished(_ parser: inout HBParser) -> Bool {
|
|
var parser2 = parser
|
|
if parser.reachedEnd() { return true }
|
|
parser2.read(while: Set(" \t"))
|
|
if parser2.current().isNewline {
|
|
parser2.unsafeAdvance()
|
|
try! parser.setPosition(parser2.position)
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
static func isStandalone(_ parser: inout HBParser, state: ParserState) -> Bool {
|
|
return state.newLine && self.hasLineFinished(&parser)
|
|
}
|
|
|
|
private static let sectionNameCharsWithoutBrackets = Set<Character>("0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ._?")
|
|
private static let sectionNameChars = Set<Character>("0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ._?()")
|
|
}
|