Allow react defaultVersion to be configurable

README.md

@@ -42,7 +42,9 @@ You should also specify settings that will be shared across all the plugin rules
  "fragment": "Fragment", // Fragment to use (may be a property of <pragma>), default to "Fragment"
  "version": "detect", // React version. "detect" automatically picks the version you have installed.
  // You can also use `16.0`, `16.3`, etc, if you want to override the detected value.
- // It will default to "latest" and warn if missing, and to "detect" in the future
+ // Defaults to the "defaultVersion" setting and warns if missing, and to "detect" in the future
+ "defaultVersion": "", // Default React version to use when the version you have installed cannot be detected.
+ // If not provided, defaults to the latest React version.
  "flowVersion": "0.53" // Flow version
  },
  "propWrapperFunctions": [

lib/util/version.js

@@ -12,6 +12,8 @@ const resolve = require('resolve');
 const semver = require('semver');
 const error = require('./error');
 
+const ULTIMATE_LATEST_SEMVER = '999.999.999';
+
 let warnedForMissingVersion = false;
 
 function resetWarningFlag() {
@@ -44,6 +46,37 @@ function resolveBasedir(contextOrFilename) {
  return process.cwd();
 }
 
+function convertConfVerToSemver(confVer) {
+ const fullSemverString = /^[0-9]+\.[0-9]+$/.test(confVer) ? `${confVer}.0` : confVer;
+ return semver.coerce(fullSemverString.split('.').map((part) => Number(part)).join('.'));
+}
+
+let defaultVersion = ULTIMATE_LATEST_SEMVER;
+
+function resetDefaultVersion() {
+ defaultVersion = ULTIMATE_LATEST_SEMVER;
+}
+
+function readDefaultReactVersionFromContext(context) {
+ // .eslintrc shared settings (https://eslint.org/docs/user-guide/configuring#adding-shared-settings)
+ if (context.settings && context.settings.react && context.settings.react.defaultVersion) {
+ let settingsDefaultVersion = context.settings.react.defaultVersion;
+ if (typeof settingsDefaultVersion !== 'string') {
+ error('Warning: default React version specified in eslint-pluigin-react-settings must be a string; '
+ + `got "${typeof settingsDefaultVersion}"`);
+ }
+ settingsDefaultVersion = String(settingsDefaultVersion);
+ const result = convertConfVerToSemver(settingsDefaultVersion);
+ if (result) {
+ defaultVersion = result.version;
+ } else {
+ error(`Warning: React version specified in eslint-plugin-react-settings must be a valid semver version, or "detect"; got “${settingsDefaultVersion}”. Falling back to latest version as default.`);
+ }
+ } else {
+ defaultVersion = ULTIMATE_LATEST_SEMVER;
+ }
+}
+
 // TODO, semver-major: remove context fallback
 function detectReactVersion(context) {
  if (cachedDetectedReactVersion) {
@@ -60,20 +93,22 @@ function detectReactVersion(context) {
  } catch (e) {
  if (e.code === 'MODULE_NOT_FOUND') {
  if (!warnedForMissingVersion) {
- error('Warning: React version was set to "detect" in eslint-plugin-react settings, '
- + 'but the "react" package is not installed. Assuming latest React version for linting.');
+ let sentence2 = 'Assuming latest React version for linting.';
+ if (defaultVersion !== ULTIMATE_LATEST_SEMVER) {
+ sentence2 = `Assuming default React version for linting: "${defaultVersion}".`;
+ }
+ error(`Warning: React version was set to "detect" in eslint-plugin-react settings, but the "react" package is not installed. ${sentence2}`);
  warnedForMissingVersion = true;
  }
- cachedDetectedReactVersion = '999.999.999';
+ cachedDetectedReactVersion = defaultVersion;
  return cachedDetectedReactVersion;
  }
  throw e;
  }
 }
 
-const defaultVersion = '999.999.999';
-
 function getReactVersionFromContext(context) {
+ readDefaultReactVersionFromContext(context);
  let confVer = defaultVersion;
  // .eslintrc shared settings (https://eslint.org/docs/user-guide/configuring#adding-shared-settings)
  if (context.settings && context.settings.react && context.settings.react.version) {
@@ -91,8 +126,8 @@ function getReactVersionFromContext(context) {
  + 'See https://github.com/jsx-eslint/eslint-plugin-react#configuration .');
  warnedForMissingVersion = true;
  }
- confVer = /^[0-9]+\.[0-9]+$/.test(confVer) ? `${confVer}.0` : confVer;
- const result = semver.coerce(confVer.split('.').map((part) => Number(part)).join('.'));
+
+ const result = convertConfVerToSemver(confVer);
  if (!result) {
  error(`Warning: React version specified in eslint-plugin-react-settings must be a valid semver version, or "detect"; got “${confVer}”`);
  }
@@ -111,7 +146,7 @@ function detectFlowVersion(context) {
  if (e.code === 'MODULE_NOT_FOUND') {
  error('Warning: Flow version was set to "detect" in eslint-plugin-react settings, '
  + 'but the "flow-bin" package is not installed. Assuming latest Flow version for linting.');
- return '999.999.999';
+ return ULTIMATE_LATEST_SEMVER;
  }
  throw e;
  }
@@ -133,8 +168,8 @@ function getFlowVersionFromContext(context) {
  } else {
  throw 'Could not retrieve flowVersion from settings'; // eslint-disable-line no-throw-literal
  }
- confVer = /^[0-9]+\.[0-9]+$/.test(confVer) ? `${confVer}.0` : confVer;
- const result = semver.coerce(confVer.split('.').map((part) => Number(part)).join('.'));
+
+ const result = convertConfVerToSemver(confVer);
  if (!result) {
  error(`Warning: Flow version specified in eslint-plugin-react-settings must be a valid semver version, or "detect"; got “${confVer}”`);
  }
@@ -158,4 +193,5 @@ module.exports = {
  testFlowVersion,
  resetWarningFlag,
  resetDetectedVersion,
+ resetDefaultVersion,
 };

tests/util/version.js

@@ -14,6 +14,7 @@ describe('Version', () => {
  expectedErrorArgs = [];
  versionUtil.resetWarningFlag();
  versionUtil.resetDetectedVersion();
+ versionUtil.resetDefaultVersion();
  });
 
  afterEach(() => {
@@ -65,6 +66,33 @@ describe('Version', () => {
  ];
  });
 
+ it('uses default version from settings if provided and react is not installed', () => {
+ context.settings.react.defaultVersion = '16.14.0';
+ sinon.stub(context, 'getFilename').callsFake(() => path.resolve(base, 'detect-version-missing', 'test.js'));
+
+ assert.equal(versionUtil.testReactVersion(context, '16.14.0'), true);
+
+ expectedErrorArgs = [
+ ['Warning: React version was set to "detect" in eslint-plugin-react settings, but the "react" package is not installed. Assuming default React version for linting: "16.14.0".'],
+ ];
+
+ delete context.settings.react.defaultVersion;
+ });
+
+ it('fails nicely with an invalid default version of react', () => {
+ context.settings.react.defaultVersion = 'not semver';
+ sinon.stub(context, 'getFilename').callsFake(() => path.resolve(base, 'detect-version-missing', 'test.js'));
+
+ assert.equal(versionUtil.testReactVersion(context, '999.999.999'), true);
+
+ expectedErrorArgs = [
+ ['Warning: React version specified in eslint-plugin-react-settings must be a valid semver version, or "detect"; got “not semver”. Falling back to latest version as default.'],
+ ['Warning: React version was set to "detect" in eslint-plugin-react settings, but the "react" package is not installed. Assuming latest React version for linting.'],
+ ];
+
+ delete context.settings.react.defaultVersion;
+ });
+
  it('warns only once for failure to detect react ', () => {
  sinon.stub(context, 'getFilename').callsFake(() => path.resolve(base, 'detect-version-missing', 'test.js'));