Replace where parameter in consume(if:) and friends by allowTokenAtStartOfLine

rdar://103774625

Author: ahoppen

Sources/SwiftParser/Attributes.swift

@@ -170,7 +170,7 @@ extension Parser {
     case .required:
       shouldParseArgument = true
     case .customAttribute:
-      shouldParseArgument = self.lookahead().isCustomAttributeArgument() && self.at(.leftParen, where: { !$0.isAtStartOfLine })
+      shouldParseArgument = self.lookahead().isCustomAttributeArgument() && self.at(.leftParen, allowTokenAtStartOfLine: false)
     case .optional:
       shouldParseArgument = self.at(.leftParen)
     }
@@ -1157,7 +1157,7 @@ extension Parser.Lookahead {
       return false
     }
 
-    if self.at(.leftParen, where: { !$0.isAtStartOfLine }) && self.lookahead().isCustomAttributeArgument() {
+    if self.at(.leftParen, allowTokenAtStartOfLine: false) && self.lookahead().isCustomAttributeArgument() {
       self.skipSingle()
     }
 

Sources/SwiftParser/Declarations.swift

@@ -820,7 +820,7 @@ extension Parser {
         let (unexpectedBeforeName, name) = self.expectIdentifier(allowIdentifierLikeKeywords: false, keywordRecovery: true)
 
         let associatedValue: RawParameterClauseSyntax?
-        if self.at(.leftParen, where: { !$0.isAtStartOfLine }) {
+        if self.at(.leftParen, allowTokenAtStartOfLine: false) {
           associatedValue = self.parseParameterClause(for: .enumCase)
         } else {
           associatedValue = nil
@@ -1016,7 +1016,7 @@ extension Parser {
   ) -> RawDeinitializerDeclSyntax {
     let (unexpectedBeforeDeinitKeyword, deinitKeyword) = self.eat(handle)
     var unexpectedNameAndSignature: [RawSyntax?] = []
-    unexpectedNameAndSignature.append(self.consume(if: .identifier, where: { !$0.isAtStartOfLine }).map(RawSyntax.init))
+    unexpectedNameAndSignature.append(self.consume(if: .identifier, allowTokenAtStartOfLine: false).map(RawSyntax.init))
     if self.at(.leftParen) && !self.currentToken.isAtStartOfLine {
       unexpectedNameAndSignature.append(RawSyntax(parseFunctionSignature()))
     }
@@ -1596,7 +1596,7 @@ extension Parser {
     }
 
     // diagnose 'throw'/'try'.
-    if let throwTry = self.consume(ifAny: [.keyword(.throw), .keyword(.try)], where: { !$0.isAtStartOfLine }) {
+    if let throwTry = self.consume(ifAny: [.keyword(.throw), .keyword(.try)], allowTokenAtStartOfLine: false) {
       return throwTry
     }
 
@@ -1853,7 +1853,7 @@ extension Parser {
     case (_, let handle)?:
       (unexpectedBeforeName, name) = self.eat(handle)
     default:
-      if let identifier = self.consume(ifAny: [.identifier, .dollarIdentifier], where: { !$0.isAtStartOfLine }) {
+      if let identifier = self.consume(ifAny: [.identifier, .dollarIdentifier], allowTokenAtStartOfLine: false) {
         // Recover if the developer tried to use an identifier as the operator name
         unexpectedBeforeName = RawUnexpectedNodesSyntax([identifier], arena: self.arena)
       } else {
@@ -2041,7 +2041,7 @@ extension Parser {
           let (unexpectedBeforeColon, colon) = self.expect(.colon)
           let (unexpectedBeforeFlag, flag) = self.expectAny([.keyword(.true), .keyword(.false)], default: .keyword(.true))
           let unexpectedAfterFlag: RawUnexpectedNodesSyntax?
-          if flag.isMissing, let unexpectedIdentifier = self.consume(if: .identifier, where: { !$0.isAtStartOfLine }) {
+          if flag.isMissing, let unexpectedIdentifier = self.consume(if: .identifier, allowTokenAtStartOfLine: false) {
             unexpectedAfterFlag = RawUnexpectedNodesSyntax([unexpectedIdentifier], arena: self.arena)
           } else {
             unexpectedAfterFlag = nil
@@ -2267,7 +2267,7 @@ extension Parser {
     }
 
     // Parse the optional parenthesized argument list.
-    let leftParen = self.consume(if: .leftParen, where: { !$0.isAtStartOfLine })
+    let leftParen = self.consume(if: .leftParen, allowTokenAtStartOfLine: false)
     let args: [RawTupleExprElementSyntax]
     let unexpectedBeforeRightParen: RawUnexpectedNodesSyntax?
     let rightParen: RawTokenSyntax?

Sources/SwiftParser/Expressions.swift

@@ -725,7 +725,7 @@ extension Parser {
       }
 
       // If there is an expr-call-suffix, parse it and form a call.
-      if let lparen = self.consume(if: .leftParen, where: { !$0.isAtStartOfLine }) {
+      if let lparen = self.consume(if: .leftParen, allowTokenAtStartOfLine: false) {
         let args = self.parseArgumentListElements(pattern: pattern)
         let (unexpectedBeforeRParen, rparen) = self.expect(.rightParen)
 
@@ -756,7 +756,7 @@ extension Parser {
 
       // Check for a [expr] suffix.
       // Note that this cannot be the start of a new line.
-      if let lsquare = self.consume(if: .leftSquareBracket, where: { !$0.isAtStartOfLine }) {
+      if let lsquare = self.consume(if: .leftSquareBracket, allowTokenAtStartOfLine: false) {
         let args: [RawTupleExprElementSyntax]
         if self.at(.rightSquareBracket) {
           args = []
@@ -997,7 +997,7 @@ extension Parser {
     while loopCondition.evaluate(currentToken) {
       // Check for a [] or .[] suffix. The latter is only permitted when there
       // are no components.
-      if self.at(.leftSquareBracket, where: { !$0.isAtStartOfLine })
+      if self.at(.leftSquareBracket, allowTokenAtStartOfLine: false)
         || (components.isEmpty && self.at(.period) && self.peek().rawTokenKind == .leftSquareBracket)
       {
         // Consume the '.', if it's allowed here.
@@ -1326,7 +1326,7 @@ extension Parser {
     }
 
     // Parse the optional parenthesized argument list.
-    let leftParen = self.consume(if: .leftParen, where: { !$0.isAtStartOfLine })
+    let leftParen = self.consume(if: .leftParen, allowTokenAtStartOfLine: false)
     let args: [RawTupleExprElementSyntax]
     let unexpectedBeforeRightParen: RawUnexpectedNodesSyntax?
     let rightParen: RawTokenSyntax?

Sources/SwiftParser/Names.swift

@@ -85,7 +85,7 @@ extension Parser {
     }
 
     // Is the current token a left paren?
-    guard self.at(.leftParen, where: { !$0.isAtStartOfLine }) else {
+    guard self.at(.leftParen, allowTokenAtStartOfLine: false) else {
       return nil
     }
 

Sources/SwiftParser/TokenConsumer.swift

@@ -59,9 +59,12 @@ extension TokenConsumer {
   /// - Returns: `true` if the given `kind` matches the current token's kind.
   public func at(
     _ kind: RawTokenKind,
-    where condition: (Lexer.Lexeme) -> Bool = { _ in true }
+    allowTokenAtStartOfLine: Bool = true
   ) -> Bool {
-    return RawTokenKindMatch(kind) ~= self.currentToken && condition(self.currentToken)
+    if !allowTokenAtStartOfLine && self.currentToken.isAtStartOfLine {
+      return false
+    }
+    return RawTokenKindMatch(kind) ~= self.currentToken
   }
 
   /// Returns whether the current token is an operator with the given `name`.
@@ -80,9 +83,12 @@ extension TokenConsumer {
   @_spi(RawSyntax)
   public func at(
     any kinds: [RawTokenKind],
-    where condition: (Lexer.Lexeme) -> Bool = { _ in true }
+    allowTokenAtStartOfLine: Bool = true
   ) -> Bool {
-    return kinds.contains(where: { RawTokenKindMatch($0) ~= self.currentToken }) && condition(self.currentToken)
+    if !allowTokenAtStartOfLine && self.currentToken.isAtStartOfLine {
+      return false
+    }
+    return kinds.contains(where: { RawTokenKindMatch($0) ~= self.currentToken })
   }
 
   /// Checks whether the parser is currently positioned at any token in `Subset`.
@@ -139,9 +145,9 @@ extension TokenConsumer {
   public mutating func consume(
     if kind: RawTokenKind,
     remapping: RawTokenKind? = nil,
-    where condition: (Lexer.Lexeme) -> Bool = { _ in true }
+    allowTokenAtStartOfLine: Bool = true
   ) -> Token? {
-    if self.at(kind, where: condition) {
+    if self.at(kind, allowTokenAtStartOfLine: allowTokenAtStartOfLine) {
       if let remapping = remapping {
         return self.consumeAnyToken(remapping: remapping)
       } else if case .keyword = kind {
@@ -173,9 +179,9 @@ extension TokenConsumer {
   @_spi(RawSyntax)
   public mutating func consume(
     ifAny kinds: [RawTokenKind],
-    where condition: (Lexer.Lexeme) -> Bool = { _ in true }
+    allowTokenAtStartOfLine: Bool = true
   ) -> Token? {
-    if self.at(any: kinds, where: condition) {
+    if self.at(any: kinds, allowTokenAtStartOfLine: allowTokenAtStartOfLine) {
       return self.consumeAnyToken()
     }
     return nil
@@ -230,11 +236,8 @@ extension TokenConsumer {
   /// - Parameter condition: An additional condition that must be satisfied for
   ///                        the token to be consumed.
   /// - Returns: A token of the given kind.
-  public mutating func expectWithoutRecovery(
-    _ kind: RawTokenKind,
-    where condition: (Lexer.Lexeme) -> Bool = { _ in true }
-  ) -> Token {
-    if let token = self.consume(if: kind, where: condition) {
+  public mutating func expectWithoutRecovery(_ kind: RawTokenKind) -> Token {
+    if let token = self.consume(if: kind) {
       return token
     } else {
       return missingToken(kind, text: nil)