Function namespaceCssVariable

packages/compiler/src/util.ts:160–177

(varName: string)

 * @returns The namespaced CSS variable name.
 */
export function namespaceCssVariable(varName: string): string {
  // TODO: Enforce this in v23. This is a breaking change.
  //       Enable tests under platform-browser and compiler matching "has a single hyphen".
  // g3-only-start
  // if (varName.startsWith('--global-') && !varName.startsWith('--global--')) {
  //   throw new Error(
  //     `CSS variable "${varName}" has a single hyphen after "--global". ` +
  //       `Use two hyphens ("--global--${varName.substring('--global-'.length)}") to opt-out of namespacing.`,
  //   );
  // }
  // g3-only-end

  if (varName.startsWith('--global--')) {
    return '--' + varName.substring('--global--'.length);
  } else {
    return '--%NS%' + varName.substring('--'.length);
  }
}