Always end interpolation even if ) is present

When parsing the end of an interpolation segment, even if there is a closing `)` present, the lexer may still think it's inside a nested position in an interpolated segment. As such, make sure to always tell it to move back to string literal mode for better diagnostics.

Author: hamishknight

Sources/SwiftParser/StringLiterals.swift

@@ -490,7 +490,7 @@ extension Parser {
  unexpectedBeforeRightParen.append(self.consumeAnyToken())
  }
  let rightParen = self.expectWithoutRecovery(.rightParen)
- if rightParen.isMissing, case .inStringInterpolation = self.currentToken.cursor.currentState {
+ if case .inStringInterpolation = self.currentToken.cursor.currentState {
  // The parser has more knowledge that we have reached the end of the
  // string interpolation now, even if we haven't seen the closing ')'.
  // For example, consider the following code

Tests/SwiftParserTest/ExpressionTests.swift

@@ -1656,13 +1656,12 @@ final class StatementExpressionTests: XCTestCase {
  func testUnterminatedInterpolationAtEndOfMultilineStringLiteral() {
  AssertParse(
  #"""
- """\({(1️⃣})
- 2️⃣"""3️⃣
+ """1️⃣\({(2️⃣})
+ """
  """#,
  diagnostics: [
- DiagnosticSpec(locationMarker: "1️⃣", message: "expected value and ')' to end tuple"),
- DiagnosticSpec(locationMarker: "2️⃣", message: #"unexpected code '"""' in string literal"#),
- DiagnosticSpec(locationMarker: "3️⃣", message: #"expected '"""' to end string literal"#),
+ DiagnosticSpec(locationMarker: "1️⃣", message: "multi-line string literal content must begin on a new line"),
+ DiagnosticSpec(locationMarker: "2️⃣", message: "expected value and ')' to end tuple"),
  ]
  )
  }

Tests/SwiftParserTest/translated/UnclosedStringInterpolationTests.swift

@@ -111,7 +111,7 @@ final class UnclosedStringInterpolationTests: XCTestCase {
  func testSkipUnexpectedOpeningParensInStringLiteral() {
  AssertParse(
  #"""
- "\(e 1️⃣H()2️⃣r
+ "\(e 1️⃣H()r2️⃣
  """#,
  diagnostics: [
  DiagnosticSpec(locationMarker: "1️⃣", message: "unexpected code 'H(' in string literal"),