paradiego

node_modules/eslint-plugin-react/lib/util/componentUtil.js

@@ -0,0 +1,190 @@
+'use strict';
+
+const doctrine = require('doctrine');
+const pragmaUtil = require('./pragma');
+const eslintUtil = require('./eslint');
+
+const getScope = eslintUtil.getScope;
+const getSourceCode = eslintUtil.getSourceCode;
+const getText = eslintUtil.getText;
+
+// eslint-disable-next-line valid-jsdoc
+/**
+ * @template {(_: object) => any} T
+ * @param {T} fn
+ * @returns {T}
+ */
+function memoize(fn) {
+  const cache = new WeakMap();
+  // @ts-ignore
+  return function memoizedFn(arg) {
+    const cachedValue = cache.get(arg);
+    if (cachedValue !== undefined) {
+      return cachedValue;
+    }
+    const v = fn(arg);
+    cache.set(arg, v);
+    return v;
+  };
+}
+
+const getPragma = memoize(pragmaUtil.getFromContext);
+const getCreateClass = memoize(pragmaUtil.getCreateClassFromContext);
+
+/**
+ * @param {ASTNode} node
+ * @param {Context} context
+ * @returns {boolean}
+ */
+function isES5Component(node, context) {
+  const pragma = getPragma(context);
+  const createClass = getCreateClass(context);
+
+  if (!node.parent || !node.parent.callee) {
+    return false;
+  }
+  const callee = node.parent.callee;
+  // React.createClass({})
+  if (callee.type === 'MemberExpression') {
+    return callee.object.name === pragma && callee.property.name === createClass;
+  }
+  // createClass({})
+  if (callee.type === 'Identifier') {
+    return callee.name === createClass;
+  }
+  return false;
+}
+
+/**
+ * Check if the node is explicitly declared as a descendant of a React Component
+ * @param {any} node
+ * @param {Context} context
+ * @returns {boolean}
+ */
+function isExplicitComponent(node, context) {
+  const sourceCode = getSourceCode(context);
+  let comment;
+  // Sometimes the passed node may not have been parsed yet by eslint, and this function call crashes.
+  // Can be removed when eslint sets "parent" property for all nodes on initial AST traversal: https://github.com/eslint/eslint-scope/issues/27
+  // eslint-disable-next-line no-warning-comments
+  // FIXME: Remove try/catch when https://github.com/eslint/eslint-scope/issues/27 is implemented.
+  try {
+    comment = sourceCode.getJSDocComment(node);
+  } catch (e) {
+    comment = null;
+  }
+
+  if (comment === null) {
+    return false;
+  }
+
+  let commentAst;
+  try {
+    commentAst = doctrine.parse(comment.value, {
+      unwrap: true,
+      tags: ['extends', 'augments'],
+    });
+  } catch (e) {
+    // handle a bug in the archived `doctrine`, see #2596
+    return false;
+  }
+
+  const relevantTags = commentAst.tags.filter((tag) => tag.name === 'React.Component' || tag.name === 'React.PureComponent');
+
+  return relevantTags.length > 0;
+}
+
+/**
+ * @param {ASTNode} node
+ * @param {Context} context
+ * @returns {boolean}
+ */
+function isES6Component(node, context) {
+  const pragma = getPragma(context);
+  if (isExplicitComponent(node, context)) {
+    return true;
+  }
+
+  if (!node.superClass) {
+    return false;
+  }
+  if (node.superClass.type === 'MemberExpression') {
+    return node.superClass.object.name === pragma
+          && /^(Pure)?Component$/.test(node.superClass.property.name);
+  }
+  if (node.superClass.type === 'Identifier') {
+    return /^(Pure)?Component$/.test(node.superClass.name);
+  }
+  return false;
+}
+
+/**
+ * Get the parent ES5 component node from the current scope
+ * @param {Context} context
+ * @param {ASTNode} node
+ * @returns {ASTNode|null}
+ */
+function getParentES5Component(context, node) {
+  let scope = getScope(context, node);
+  while (scope) {
+    // @ts-ignore
+    node = scope.block && scope.block.parent && scope.block.parent.parent;
+    if (node && isES5Component(node, context)) {
+      return node;
+    }
+    scope = scope.upper;
+  }
+  return null;
+}
+
+/**
+ * Get the parent ES6 component node from the current scope
+ * @param {Context} context
+ * @param {ASTNode} node
+ * @returns {ASTNode | null}
+ */
+function getParentES6Component(context, node) {
+  let scope = getScope(context, node);
+  while (scope && scope.type !== 'class') {
+    scope = scope.upper;
+  }
+  node = scope && scope.block;
+  if (!node || !isES6Component(node, context)) {
+    return null;
+  }
+  return node;
+}
+
+/**
+ * Checks if a component extends React.PureComponent
+ * @param {ASTNode} node
+ * @param {Context} context
+ * @returns {boolean}
+ */
+function isPureComponent(node, context) {
+  const pragma = getPragma(context);
+  if (node.superClass) {
+    return new RegExp(`^(${pragma}\\.)?PureComponent$`).test(getText(context, node.superClass));
+  }
+  return false;
+}
+
+/**
+ * @param {ASTNode} node
+ * @returns {boolean}
+ */
+function isStateMemberExpression(node) {
+  return node.type === 'MemberExpression'
+    && node.object.type === 'ThisExpression'
+    && node.property.name === 'state';
+}
+
+module.exports = {
+  isES5Component,
+  isES6Component,
+  getParentES5Component,
+  getParentES6Component,
+  isExplicitComponent,
+  isPureComponent,
+  isStateMemberExpression,
+};