github-pages-deploy-action/node_modules/eslint-plugin-react/lib/util/ast.js
2020-03-06 22:45:40 -05:00

216 lines
5.3 KiB
JavaScript

/**
* @fileoverview Utility functions for AST
*/
'use strict';
/**
* Find a return statment in the current node
*
* @param {ASTNode} node The AST node being checked
* @returns {ASTNode | false}
*/
function findReturnStatement(node) {
if (
(!node.value || !node.value.body || !node.value.body.body) &&
(!node.body || !node.body.body)
) {
return false;
}
const bodyNodes = (node.value ? node.value.body.body : node.body.body);
return (function loopNodes(nodes) {
let i = nodes.length - 1;
for (; i >= 0; i--) {
if (nodes[i].type === 'ReturnStatement') {
return nodes[i];
}
if (nodes[i].type === 'SwitchStatement') {
let j = nodes[i].cases.length - 1;
for (; j >= 0; j--) {
return loopNodes(nodes[i].cases[j].consequent);
}
}
}
return false;
}(bodyNodes));
}
/**
* Get node with property's name
* @param {Object} node - Property.
* @returns {Object} Property name node.
*/
function getPropertyNameNode(node) {
if (node.key || ['MethodDefinition', 'Property'].indexOf(node.type) !== -1) {
return node.key;
}
if (node.type === 'MemberExpression') {
return node.property;
}
return null;
}
/**
* Get properties name
* @param {Object} node - Property.
* @returns {String} Property name.
*/
function getPropertyName(node) {
const nameNode = getPropertyNameNode(node);
return nameNode ? nameNode.name : '';
}
/**
* Get properties for a given AST node
* @param {ASTNode} node The AST node being checked.
* @returns {Array} Properties array.
*/
function getComponentProperties(node) {
switch (node.type) {
case 'ClassDeclaration':
case 'ClassExpression':
return node.body.body;
case 'ObjectExpression':
return node.properties;
default:
return [];
}
}
/**
* Gets the first node in a line from the initial node, excluding whitespace.
* @param {Object} context The node to check
* @param {ASTNode} node The node to check
* @return {ASTNode} the first node in the line
*/
function getFirstNodeInLine(context, node) {
const sourceCode = context.getSourceCode();
let token = node;
let lines;
do {
token = sourceCode.getTokenBefore(token);
lines = token.type === 'JSXText' ?
token.value.split('\n') :
null;
} while (
token.type === 'JSXText' &&
/^\s*$/.test(lines[lines.length - 1])
);
return token;
}
/**
* Checks if the node is the first in its line, excluding whitespace.
* @param {Object} context The node to check
* @param {ASTNode} node The node to check
* @return {Boolean} true if it's the first node in its line
*/
function isNodeFirstInLine(context, node) {
const token = getFirstNodeInLine(context, node);
const startLine = node.loc.start.line;
const endLine = token ? token.loc.end.line : -1;
return startLine !== endLine;
}
/**
* Checks if the node is a function or arrow function expression.
* @param {ASTNode} node The node to check
* @return {Boolean} true if it's a function-like expression
*/
function isFunctionLikeExpression(node) {
return node.type === 'FunctionExpression' || node.type === 'ArrowFunctionExpression';
}
/**
* Checks if the node is a function.
* @param {ASTNode} node The node to check
* @return {Boolean} true if it's a function
*/
function isFunction(node) {
return node.type === 'FunctionExpression' || node.type === 'FunctionDeclaration';
}
/**
* Checks if the node is a class.
* @param {ASTNode} node The node to check
* @return {Boolean} true if it's a class
*/
function isClass(node) {
return node.type === 'ClassDeclaration' || node.type === 'ClassExpression';
}
/**
* Removes quotes from around an identifier.
* @param {string} string the identifier to strip
* @returns {string}
*/
function stripQuotes(string) {
return string.replace(/^'|'$/g, '');
}
/**
* Retrieve the name of a key node
* @param {Context} context The AST node with the key.
* @param {ASTNode} node The AST node with the key.
* @return {string} the name of the key
*/
function getKeyValue(context, node) {
if (node.type === 'ObjectTypeProperty') {
const tokens = context.getFirstTokens(node, 2);
return (tokens[0].value === '+' || tokens[0].value === '-' ?
tokens[1].value :
stripQuotes(tokens[0].value)
);
}
if (node.type === 'GenericTypeAnnotation') {
return node.id.name;
}
if (node.type === 'ObjectTypeAnnotation') {
return;
}
const key = node.key || node.argument;
return key.type === 'Identifier' ? key.name : key.value;
}
/**
* Checks if a node is being assigned a value: props.bar = 'bar'
* @param {ASTNode} node The AST node being checked.
* @returns {Boolean}
*/
function isAssignmentLHS(node) {
return (
node.parent &&
node.parent.type === 'AssignmentExpression' &&
node.parent.left === node
);
}
/**
* Extracts the expression node that is wrapped inside a TS type assertion
*
* @param {ASTNode} node - potential TS node
* @returns {ASTNode} - unwrapped expression node
*/
function unwrapTSAsExpression(node) {
if (node && node.type === 'TSAsExpression') return node.expression;
return node;
}
module.exports = {
findReturnStatement,
getFirstNodeInLine,
getPropertyName,
getPropertyNameNode,
getComponentProperties,
getKeyValue,
isAssignmentLHS,
isClass,
isFunction,
isFunctionLikeExpression,
isNodeFirstInLine,
unwrapTSAsExpression
};