Method parseArgument

packages/icu-messageformat-parser/parser.ts:530–614

(
    nestingLevel: number,
    expectingCloseTag: boolean
  )

  }

  private parseArgument(
    nestingLevel: number,
    expectingCloseTag: boolean
  ): Result<MessageFormatElement, ParserError> {
    const openingBracePosition = this.clonePosition()
    this.bump() // `{`

    this.bumpSpace()

    if (this.isEOF()) {
      return this.error(
        ErrorKind.EXPECT_ARGUMENT_CLOSING_BRACE,
        createLocation(openingBracePosition, this.clonePosition())
      )
    }

    if (this.char() === 125 /* `}` */) {
      this.bump()
      return this.error(
        ErrorKind.EMPTY_ARGUMENT,
        createLocation(openingBracePosition, this.clonePosition())
      )
    }

    // argument name
    let value = this.parseIdentifierIfPossible().value
    if (!value) {
      return this.error(
        ErrorKind.MALFORMED_ARGUMENT,
        createLocation(openingBracePosition, this.clonePosition())
      )
    }

    this.bumpSpace()

    if (this.isEOF()) {
      return this.error(
        ErrorKind.EXPECT_ARGUMENT_CLOSING_BRACE,
        createLocation(openingBracePosition, this.clonePosition())
      )
    }

    switch (this.char()) {
      // Simple argument: `{name}`
      case 125 /* `}` */: {
        this.bump() // `}`
        return {
          val: {
            type: TYPE.argument,
            // value does not include the opening and closing braces.
            value,
            location: createLocation(
              openingBracePosition,
              this.clonePosition()
            ),
          },
          err: null,
        }