Function formatMessage

src/adapter/messageFormat.ts:68–122

(
  format: string,
  substitutions: ReadonlyArray<T>,
  formatters: Formatters<T>,
)

}

export function formatMessage<T>(
  format: string,
  substitutions: ReadonlyArray<T>,
  formatters: Formatters<T>,
): { result: string; usedAllSubs: boolean } {
  const tokens = tokenizeFormatString(format, Array.from(formatters.keys()));
  const usedSubstitutionIndexes = new Set<number>();
  const defaultFormatter = formatters.get('');
  if (!defaultFormatter) {
    throw new Error('Expected to hav a default formatter');
  }

  const builder = new BudgetStringBuilder(maxMessageFormatLength);
  let cssFormatApplied = false;
  for (let i = 0; builder.checkBudget() && i < tokens.length; ++i) {
    const token = tokens[i];
    if (token.type === 'string') {
      builder.append(token.value);
      continue;
    }

    const index = token.substitutionIndex;
    if (index >= substitutions.length) {
      // If there are not enough substitutions for the current substitutionIndex
      // just output the format specifier literally and move on.
      builder.append('%' + (token.precision || '') + token.specifier);
      continue;
    }
    usedSubstitutionIndexes.add(index);
    if (token.specifier === 'c') cssFormatApplied = true;
    const formatter = formatters.get(token.specifier) || defaultFormatter;
    builder.append(
      formatter(substitutions[index], { budget: builder.budget(), quoted: false, ansi: true }),
    );
  }

  if (cssFormatApplied) builder.append('\x1b[0m'); // clear format

  for (let i = 0; builder.checkBudget() && i < substitutions.length; ++i) {
    if (usedSubstitutionIndexes.has(i)) continue;
    usedSubstitutionIndexes.add(i);
    if (format || i) {
      // either we are second argument or we had format.
      builder.append(' ');
    }
    builder.append(
      defaultFormatter(substitutions[i], { budget: builder.budget(), quoted: false, ansi: true }),
    );
  }

  return {
    result: builder.build(),
    usedAllSubs: usedSubstitutionIndexes.size === substitutions.length,
  };
}

function escapeAnsiColor(colorString: string): number | undefined {
  try {