react/src/constants.js

// @flow

// Flip this flag to true to enable verbose console debug logging.
export const __DEBUG__ = false;

export const TREE_OPERATION_ADD = 1;
export const TREE_OPERATION_REMOVE = 2;
export const TREE_OPERATION_REORDER_CHILDREN = 3;
export const TREE_OPERATION_UPDATE_TREE_BASE_DURATION = 4;

export const LOCAL_STORAGE_FILTER_PREFERENCES_KEY =
  'React::DevTools::componentFilters';

export const SESSION_STORAGE_LAST_SELECTION_KEY =
  'React::DevTools::lastSelection';

export const SESSION_STORAGE_RECORD_CHANGE_DESCRIPTIONS_KEY =
  'React::DevTools::recordChangeDescriptions';

export const SESSION_STORAGE_RELOAD_AND_PROFILE_KEY =
  'React::DevTools::reloadAndProfile';

export const LOCAL_STORAGE_SHOULD_PATCH_CONSOLE_KEY =
  'React::DevTools::appendComponentStack';

export const PROFILER_EXPORT_VERSION = 4;

export const CHANGE_LOG_URL =
  'https://github.com/bvaughn/react-devtools-experimental/blob/master/CHANGELOG.md';

// HACK
//
// Extracting during build time avoids a temporarily invalid state for the inline target.
// Sometimes the inline target is rendered before root styles are applied,
// which would result in e.g. NaN itemSize being passed to react-window list.
//
// We can't use the Webpack loader syntax in the context of Jest though,
// so tests need some reasonably meaningful fallback value.
let COMFORTABLE_LINE_HEIGHT = 15;
let COMPACT_LINE_HEIGHT = 10;

if (!__TEST__) {
  // $FlowFixMe
  const rawStyleString = require('!!raw-loader!src/devtools/views/root.css') // eslint-disable-line import/no-webpack-loader-syntax
    .default;

  const extractVar = varName => {
    const regExp = new RegExp(`${varName}: ([0-9]+)`);
    const match = rawStyleString.match(regExp);
    return parseInt(match[1], 10);
  };

  COMFORTABLE_LINE_HEIGHT = extractVar('comfortable-line-height-data');
  COMPACT_LINE_HEIGHT = extractVar('compact-line-height-data');
}

export { COMFORTABLE_LINE_HEIGHT, COMPACT_LINE_HEIGHT };