You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
290 lines
9.3 KiB
290 lines
9.3 KiB
/**
|
|
* @fileoverview Restrict usage of duplicate imports.
|
|
* @author Simen Bekkhus
|
|
*/
|
|
"use strict";
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Helpers
|
|
//------------------------------------------------------------------------------
|
|
|
|
const NAMED_TYPES = ["ImportSpecifier", "ExportSpecifier"];
|
|
const NAMESPACE_TYPES = [
|
|
"ImportNamespaceSpecifier",
|
|
"ExportNamespaceSpecifier"
|
|
];
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Rule Definition
|
|
//------------------------------------------------------------------------------
|
|
|
|
/**
|
|
* Check if an import/export type belongs to (ImportSpecifier|ExportSpecifier) or (ImportNamespaceSpecifier|ExportNamespaceSpecifier).
|
|
* @param {string} importExportType An import/export type to check.
|
|
* @param {string} type Can be "named" or "namespace"
|
|
* @returns {boolean} True if import/export type belongs to (ImportSpecifier|ExportSpecifier) or (ImportNamespaceSpecifier|ExportNamespaceSpecifier) and false if it doesn't.
|
|
*/
|
|
function isImportExportSpecifier(importExportType, type) {
|
|
const arrayToCheck = type === "named" ? NAMED_TYPES : NAMESPACE_TYPES;
|
|
|
|
return arrayToCheck.includes(importExportType);
|
|
}
|
|
|
|
/**
|
|
* Return the type of (import|export).
|
|
* @param {ASTNode} node A node to get.
|
|
* @returns {string} The type of the (import|export).
|
|
*/
|
|
function getImportExportType(node) {
|
|
if (node.specifiers && node.specifiers.length > 0) {
|
|
const nodeSpecifiers = node.specifiers;
|
|
const index = nodeSpecifiers.findIndex(
|
|
({ type }) =>
|
|
isImportExportSpecifier(type, "named") ||
|
|
isImportExportSpecifier(type, "namespace")
|
|
);
|
|
const i = index > -1 ? index : 0;
|
|
|
|
return nodeSpecifiers[i].type;
|
|
}
|
|
if (node.type === "ExportAllDeclaration") {
|
|
if (node.exported) {
|
|
return "ExportNamespaceSpecifier";
|
|
}
|
|
return "ExportAll";
|
|
}
|
|
return "SideEffectImport";
|
|
}
|
|
|
|
/**
|
|
* Returns a boolean indicates if two (import|export) can be merged
|
|
* @param {ASTNode} node1 A node to check.
|
|
* @param {ASTNode} node2 A node to check.
|
|
* @returns {boolean} True if two (import|export) can be merged, false if they can't.
|
|
*/
|
|
function isImportExportCanBeMerged(node1, node2) {
|
|
const importExportType1 = getImportExportType(node1);
|
|
const importExportType2 = getImportExportType(node2);
|
|
|
|
if (
|
|
(importExportType1 === "ExportAll" &&
|
|
importExportType2 !== "ExportAll" &&
|
|
importExportType2 !== "SideEffectImport") ||
|
|
(importExportType1 !== "ExportAll" &&
|
|
importExportType1 !== "SideEffectImport" &&
|
|
importExportType2 === "ExportAll")
|
|
) {
|
|
return false;
|
|
}
|
|
if (
|
|
(isImportExportSpecifier(importExportType1, "namespace") &&
|
|
isImportExportSpecifier(importExportType2, "named")) ||
|
|
(isImportExportSpecifier(importExportType2, "namespace") &&
|
|
isImportExportSpecifier(importExportType1, "named"))
|
|
) {
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Returns a boolean if we should report (import|export).
|
|
* @param {ASTNode} node A node to be reported or not.
|
|
* @param {[ASTNode]} previousNodes An array contains previous nodes of the module imported or exported.
|
|
* @returns {boolean} True if the (import|export) should be reported.
|
|
*/
|
|
function shouldReportImportExport(node, previousNodes) {
|
|
let i = 0;
|
|
|
|
while (i < previousNodes.length) {
|
|
if (isImportExportCanBeMerged(node, previousNodes[i])) {
|
|
return true;
|
|
}
|
|
i++;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Returns array contains only nodes with declarations types equal to type.
|
|
* @param {[{node: ASTNode, declarationType: string}]} nodes An array contains objects, each object contains a node and a declaration type.
|
|
* @param {string} type Declaration type.
|
|
* @returns {[ASTNode]} An array contains only nodes with declarations types equal to type.
|
|
*/
|
|
function getNodesByDeclarationType(nodes, type) {
|
|
return nodes
|
|
.filter(({ declarationType }) => declarationType === type)
|
|
.map(({ node }) => node);
|
|
}
|
|
|
|
/**
|
|
* Returns the name of the module imported or re-exported.
|
|
* @param {ASTNode} node A node to get.
|
|
* @returns {string} The name of the module, or empty string if no name.
|
|
*/
|
|
function getModule(node) {
|
|
if (node && node.source && node.source.value) {
|
|
return node.source.value.trim();
|
|
}
|
|
return "";
|
|
}
|
|
|
|
/**
|
|
* Checks if the (import|export) can be merged with at least one import or one export, and reports if so.
|
|
* @param {RuleContext} context The ESLint rule context object.
|
|
* @param {ASTNode} node A node to get.
|
|
* @param {Map} modules A Map object contains as a key a module name and as value an array contains objects, each object contains a node and a declaration type.
|
|
* @param {string} declarationType A declaration type can be an import or export.
|
|
* @param {boolean} includeExports Whether or not to check for exports in addition to imports.
|
|
* @returns {void} No return value.
|
|
*/
|
|
function checkAndReport(
|
|
context,
|
|
node,
|
|
modules,
|
|
declarationType,
|
|
includeExports
|
|
) {
|
|
const module = getModule(node);
|
|
|
|
if (modules.has(module)) {
|
|
const previousNodes = modules.get(module);
|
|
const messagesIds = [];
|
|
const importNodes = getNodesByDeclarationType(previousNodes, "import");
|
|
let exportNodes;
|
|
|
|
if (includeExports) {
|
|
exportNodes = getNodesByDeclarationType(previousNodes, "export");
|
|
}
|
|
if (declarationType === "import") {
|
|
if (shouldReportImportExport(node, importNodes)) {
|
|
messagesIds.push("import");
|
|
}
|
|
if (includeExports) {
|
|
if (shouldReportImportExport(node, exportNodes)) {
|
|
messagesIds.push("importAs");
|
|
}
|
|
}
|
|
} else if (declarationType === "export") {
|
|
if (shouldReportImportExport(node, exportNodes)) {
|
|
messagesIds.push("export");
|
|
}
|
|
if (shouldReportImportExport(node, importNodes)) {
|
|
messagesIds.push("exportAs");
|
|
}
|
|
}
|
|
messagesIds.forEach(messageId =>
|
|
context.report({
|
|
node,
|
|
messageId,
|
|
data: {
|
|
module
|
|
}
|
|
}));
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @callback nodeCallback
|
|
* @param {ASTNode} node A node to handle.
|
|
*/
|
|
|
|
/**
|
|
* Returns a function handling the (imports|exports) of a given file
|
|
* @param {RuleContext} context The ESLint rule context object.
|
|
* @param {Map} modules A Map object contains as a key a module name and as value an array contains objects, each object contains a node and a declaration type.
|
|
* @param {string} declarationType A declaration type can be an import or export.
|
|
* @param {boolean} includeExports Whether or not to check for exports in addition to imports.
|
|
* @returns {nodeCallback} A function passed to ESLint to handle the statement.
|
|
*/
|
|
function handleImportsExports(
|
|
context,
|
|
modules,
|
|
declarationType,
|
|
includeExports
|
|
) {
|
|
return function(node) {
|
|
const module = getModule(node);
|
|
|
|
if (module) {
|
|
checkAndReport(
|
|
context,
|
|
node,
|
|
modules,
|
|
declarationType,
|
|
includeExports
|
|
);
|
|
const currentNode = { node, declarationType };
|
|
let nodes = [currentNode];
|
|
|
|
if (modules.has(module)) {
|
|
const previousNodes = modules.get(module);
|
|
|
|
nodes = [...previousNodes, currentNode];
|
|
}
|
|
modules.set(module, nodes);
|
|
}
|
|
};
|
|
}
|
|
|
|
/** @type {import('../shared/types').Rule} */
|
|
module.exports = {
|
|
meta: {
|
|
type: "problem",
|
|
|
|
docs: {
|
|
description: "Disallow duplicate module imports",
|
|
recommended: false,
|
|
url: "https://eslint.org/docs/latest/rules/no-duplicate-imports"
|
|
},
|
|
|
|
schema: [
|
|
{
|
|
type: "object",
|
|
properties: {
|
|
includeExports: {
|
|
type: "boolean",
|
|
default: false
|
|
}
|
|
},
|
|
additionalProperties: false
|
|
}
|
|
],
|
|
|
|
messages: {
|
|
import: "'{{module}}' import is duplicated.",
|
|
importAs: "'{{module}}' import is duplicated as export.",
|
|
export: "'{{module}}' export is duplicated.",
|
|
exportAs: "'{{module}}' export is duplicated as import."
|
|
}
|
|
},
|
|
|
|
create(context) {
|
|
const includeExports = (context.options[0] || {}).includeExports,
|
|
modules = new Map();
|
|
const handlers = {
|
|
ImportDeclaration: handleImportsExports(
|
|
context,
|
|
modules,
|
|
"import",
|
|
includeExports
|
|
)
|
|
};
|
|
|
|
if (includeExports) {
|
|
handlers.ExportNamedDeclaration = handleImportsExports(
|
|
context,
|
|
modules,
|
|
"export",
|
|
includeExports
|
|
);
|
|
handlers.ExportAllDeclaration = handleImportsExports(
|
|
context,
|
|
modules,
|
|
"export",
|
|
includeExports
|
|
);
|
|
}
|
|
return handlers;
|
|
}
|
|
};
|