es-syntax.js

/**
 * @author Toru Nagashima
 * See LICENSE file in root directory for full license.
 */
"use strict"

const { rules: esRules } = require("eslint-plugin-es-x")
const { getInnermostScope } = require("@eslint-community/eslint-utils")
const { Range } = require("semver")
const rangeSubset = require("semver/ranges/subset")
const getConfiguredNodeVersion = require("../../util/get-configured-node-version")
const getSemverRange = require("../../util/get-semver-range")
const mergeVisitorsInPlace = require("../../util/merge-visitors-in-place")

const getOrSet = /^(?:g|s)et$/u
const features = {
    //--------------------------------------------------------------------------
    // ES2015
    //--------------------------------------------------------------------------
    arrowFunctions: {
        ruleId: "no-arrow-functions",
        cases: [
            {
                supported: "4.0.0",
                messageId: "no-arrow-functions",
            },
        ],
    },
    binaryNumericLiterals: {
        ruleId: "no-binary-numeric-literals",
        cases: [
            {
                supported: "4.0.0",
                messageId: "no-binary-numeric-literals",
            },
        ],
    },
    blockScopedFunctions: {
        ruleId: "no-block-scoped-functions",
        cases: [
            {
                supported: "6.0.0",
                test: info => !info.isStrict,
                messageId: "no-block-scoped-functions-sloppy",
            },
            {
                supported: "4.0.0",
                messageId: "no-block-scoped-functions-strict",
            },
        ],
    },
    blockScopedVariables: {
        ruleId: "no-block-scoped-variables",
        cases: [
            {
                supported: "6.0.0",
                test: info => !info.isStrict,
                messageId: "no-block-scoped-variables-sloppy",
            },
            {
                supported: "4.0.0",
                messageId: "no-block-scoped-variables-strict",
            },
        ],
    },
    classes: {
        ruleId: "no-classes",
        cases: [
            {
                supported: "6.0.0",
                test: info => !info.isStrict,
                messageId: "no-classes-sloppy",
            },
            {
                supported: "4.0.0",
                messageId: "no-classes-strict",
            },
        ],
    },
    computedProperties: {
        ruleId: "no-computed-properties",
        cases: [
            {
                supported: "4.0.0",
                messageId: "no-computed-properties",
            },
        ],
    },
    defaultParameters: {
        ruleId: "no-default-parameters",
        cases: [
            {
                supported: "6.0.0",
                messageId: "no-default-parameters",
            },
        ],
    },
    destructuring: {
        ruleId: "no-destructuring",
        cases: [
            {
                supported: "6.0.0",
                messageId: "no-destructuring",
            },
        ],
    },
    forOfLoops: {
        ruleId: "no-for-of-loops",
        cases: [
            {
                supported: "0.12.0",
                messageId: "no-for-of-loops",
            },
        ],
    },
    generators: {
        ruleId: "no-generators",
        cases: [
            {
                supported: "4.0.0",
                messageId: "no-generators",
            },
        ],
    },
    modules: {
        ruleId: "no-modules",
        cases: [
            {
                supported: new Range("^12.17 || >=13.2"),
                messageId: "no-modules",
            },
        ],
    },
    "new.target": {
        ruleId: "no-new-target",
        cases: [
            {
                supported: "5.0.0",
                messageId: "no-new-target",
            },
        ],
    },
    objectSuperProperties: {
        ruleId: "no-object-super-properties",
        cases: [
            {
                supported: "4.0.0",
                messageId: "no-object-super-properties",
            },
        ],
    },
    octalNumericLiterals: {
        ruleId: "no-octal-numeric-literals",
        cases: [
            {
                supported: "4.0.0",
                messageId: "no-octal-numeric-literals",
            },
        ],
    },
    propertyShorthands: {
        ruleId: "no-property-shorthands",
        cases: [
            {
                supported: "6.0.0",
                test: info =>
                    info.node.shorthand && getOrSet.test(info.node.key.name),
                messageId: "no-property-shorthands-getset",
            },
            {
                supported: "4.0.0",
                messageId: "no-property-shorthands",
            },
        ],
    },
    regexpU: {
        ruleId: "no-regexp-u-flag",
        cases: [
            {
                supported: "6.0.0",
                messageId: "no-regexp-u-flag",
            },
        ],
    },
    regexpY: {
        ruleId: "no-regexp-y-flag",
        cases: [
            {
                supported: "6.0.0",
                messageId: "no-regexp-y-flag",
            },
        ],
    },
    restParameters: {
        ruleId: "no-rest-parameters",
        cases: [
            {
                supported: "6.0.0",
                messageId: "no-rest-parameters",
            },
        ],
    },
    spreadElements: {
        ruleId: "no-spread-elements",
        cases: [
            {
                supported: "5.0.0",
                messageId: "no-spread-elements",
            },
        ],
    },
    templateLiterals: {
        ruleId: "no-template-literals",
        cases: [
            {
                supported: "4.0.0",
                messageId: "no-template-literals",
            },
        ],
    },
    unicodeCodePointEscapes: {
        ruleId: "no-unicode-codepoint-escapes",
        cases: [
            {
                supported: "4.0.0",
                messageId: "no-unicode-codepoint-escapes",
            },
        ],
    },

    //--------------------------------------------------------------------------
    // ES2016
    //--------------------------------------------------------------------------
    exponentialOperators: {
        ruleId: "no-exponential-operators",
        cases: [
            {
                supported: "7.0.0",
                messageId: "no-exponential-operators",
            },
        ],
    },

    //--------------------------------------------------------------------------
    // ES2017
    //--------------------------------------------------------------------------
    asyncFunctions: {
        ruleId: "no-async-functions",
        cases: [
            {
                supported: "7.6.0",
                messageId: "no-async-functions",
            },
        ],
    },
    trailingCommasInFunctions: {
        ruleId: "no-trailing-function-commas",
        cases: [
            {
                supported: "8.0.0",
                messageId: "no-trailing-function-commas",
            },
        ],
    },

    //--------------------------------------------------------------------------
    // ES2018
    //--------------------------------------------------------------------------
    asyncIteration: {
        ruleId: "no-async-iteration",
        cases: [
            {
                supported: "10.0.0",
                messageId: "no-async-iteration",
            },
        ],
    },
    malformedTemplateLiterals: {
        ruleId: "no-malformed-template-literals",
        cases: [
            {
                supported: "8.10.0",
                messageId: "no-malformed-template-literals",
            },
        ],
    },
    regexpLookbehind: {
        ruleId: "no-regexp-lookbehind-assertions",
        cases: [
            {
                supported: "8.10.0",
                messageId: "no-regexp-lookbehind-assertions",
            },
        ],
    },
    regexpNamedCaptureGroups: {
        ruleId: "no-regexp-named-capture-groups",
        cases: [
            {
                supported: "10.0.0",
                messageId: "no-regexp-named-capture-groups",
            },
        ],
    },
    regexpS: {
        ruleId: "no-regexp-s-flag",
        cases: [
            {
                supported: "8.10.0",
                messageId: "no-regexp-s-flag",
            },
        ],
    },
    regexpUnicodeProperties: {
        ruleId: "no-regexp-unicode-property-escapes",
        cases: [
            {
                supported: "10.0.0",
                messageId: "no-regexp-unicode-property-escapes",
            },
        ],
    },
    restSpreadProperties: {
        ruleId: "no-rest-spread-properties",
        cases: [
            {
                supported: "8.3.0",
                messageId: "no-rest-spread-properties",
            },
        ],
    },

    //--------------------------------------------------------------------------
    // ES2019
    //--------------------------------------------------------------------------
    jsonSuperset: {
        ruleId: "no-json-superset",
        cases: [
            {
                supported: "10.0.0",
                messageId: "no-json-superset",
            },
        ],
    },
    optionalCatchBinding: {
        ruleId: "no-optional-catch-binding",
        cases: [
            {
                supported: "10.0.0",
                messageId: "no-optional-catch-binding",
            },
        ],
    },

    //--------------------------------------------------------------------------
    // ES2020
    //--------------------------------------------------------------------------
    bigint: {
        ruleId: "no-bigint",
        cases: [
            {
                supported: "10.4.0",
                test: info => info.node.type === "Literal",
                messageId: "no-bigint",
            },
            {
                supported: null,
                test: ({ node }) =>
                    node.type === "Literal" &&
                    (node.parent.type === "Property" ||
                        node.parent.type === "MethodDefinition") &&
                    !node.parent.computed &&
                    node.parent.key === node,
                messageId: "no-bigint-property-names",
            },
        ],
    },
    dynamicImport: {
        ruleId: "no-dynamic-import",
        cases: [
            {
                supported: new Range("^12.17 || >=13.2"),
                messageId: "no-dynamic-import",
            },
        ],
    },
    optionalChaining: {
        ruleId: "no-optional-chaining",
        cases: [
            {
                supported: "14.0.0",
                messageId: "no-optional-chaining",
            },
        ],
    },
    nullishCoalescingOperators: {
        ruleId: "no-nullish-coalescing-operators",
        cases: [
            {
                supported: "14.0.0",
                messageId: "no-nullish-coalescing-operators",
            },
        ],
    },
}
const keywords = Object.keys(features)

/**
 * Parses the options.
 * @param {RuleContext} context The rule context.
 * @returns {{version:Range,ignores:Set<string>}} Parsed value.
 */
function parseOptions(context) {
    const raw = context.options[0] || {}
    const version = getConfiguredNodeVersion(context)
    const ignores = new Set(raw.ignores || [])

    return Object.freeze({ version, ignores })
}

/**
 * Find the scope that a given node belongs to.
 * @param {Scope} initialScope The initial scope to find.
 * @param {Node} node The AST node.
 * @returns {Scope} The scope that the node belongs to.
 */
function normalizeScope(initialScope, node) {
    let scope = getInnermostScope(initialScope, node)

    while (scope && scope.block === node) {
        scope = scope.upper
    }

    return scope
}

/**
 * Define the visitor object as merging the rules of eslint-plugin-es-x.
 * @param {RuleContext} context The rule context.
 * @param {{version:Range,ignores:Set<string>}} options The options.
 * @returns {object} The defined visitor.
 */
function defineVisitor(context, options) {
    const testInfoPrototype = {
        get isStrict() {
            return normalizeScope(context.getScope(), this.node).isStrict
        },
    }

    /**
     * Check whether a given case object is full-supported on the configured node version.
     * @param {{supported:string}} aCase The case object to check.
     * @returns {boolean} `true` if it's supporting.
     */
    function isNotSupportingVersion(aCase) {
        if (!aCase.supported) {
            return true
        }

        const supported =
            typeof aCase.supported === "string"
                ? getSemverRange(`>=${aCase.supported}`)
                : aCase.supported
        return !rangeSubset(options.version, supported)
    }

    /**
     * Define the predicate function to check whether a given case object is supported on the configured node version.
     * @param {Node} node The node which is reported.
     * @returns {function(aCase:{supported:string}):boolean} The predicate function.
     */
    function isNotSupportingOn(node) {
        return aCase =>
            isNotSupportingVersion(aCase) &&
            (!aCase.test || aCase.test({ node, __proto__: testInfoPrototype }))
    }

    return (
        keywords
            // Omit full-supported features and ignored features by options
            // because this rule never reports those.
            .filter(
                keyword =>
                    !options.ignores.has(keyword) &&
                    features[keyword].cases.some(isNotSupportingVersion)
            )
            // Merge remaining features with overriding `context.report()`.
            .reduce((visitor, keyword) => {
                const { ruleId, cases } = features[keyword]
                const rule = esRules[ruleId]
                const thisContext = {
                    __proto__: context,

                    // Override `context.report()` then:
                    // - ignore if it's supported.
                    // - override reporting messages.
                    report(descriptor) {
                        // Set additional information.
                        if (descriptor.data) {
                            descriptor.data.version = options.version.raw
                        } else {
                            descriptor.data = { version: options.version.raw }
                        }
                        descriptor.fix = undefined

                        // Test and report.
                        const node = descriptor.node
                        const hitCase = cases.find(isNotSupportingOn(node))
                        if (hitCase) {
                            descriptor.messageId = hitCase.messageId
                            descriptor.data.supported = hitCase.supported
                            super.report(descriptor)
                        }
                    },
                }
                return mergeVisitorsInPlace(visitor, rule.create(thisContext))
            }, {})
    )
}

module.exports = {
    meta: {
        docs: {
            description:
                "disallow unsupported ECMAScript syntax on the specified version",
            recommended: true,
            url: "https://github.com/eslint-community/eslint-plugin-n/blob/HEAD/docs/rules/no-unsupported-features/es-syntax.md",
        },
        type: "problem",
        fixable: null,
        schema: [
            {
                type: "object",
                properties: {
                    version: getConfiguredNodeVersion.schema,
                    ignores: {
                        type: "array",
                        items: {
                            enum: Object.keys(features),
                        },
                        uniqueItems: true,
                    },
                },
                additionalProperties: false,
            },
        ],
        messages: {
            //------------------------------------------------------------------
            // ES2015
            //------------------------------------------------------------------
            "no-arrow-functions":
                "Arrow functions are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-binary-numeric-literals":
                "Binary numeric literals are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-block-scoped-functions-strict":
                "Block-scoped functions in strict mode are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-block-scoped-functions-sloppy":
                "Block-scoped functions in non-strict mode are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-block-scoped-variables-strict":
                "Block-scoped variables in strict mode are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-block-scoped-variables-sloppy":
                "Block-scoped variables in non-strict mode are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-classes-strict":
                "Classes in strict mode are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-classes-sloppy":
                "Classes in non-strict mode are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-computed-properties":
                "Computed properties are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-default-parameters":
                "Default parameters are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-destructuring":
                "Destructuring is not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-for-of-loops":
                "'for-of' loops are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-generators":
                "Generator functions are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-modules":
                "Import and export declarations are not supported yet.",
            "no-new-target":
                "'new.target' is not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-object-super-properties":
                "'super' in object literals is not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-octal-numeric-literals":
                "Octal numeric literals are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-property-shorthands":
                "Property shorthands are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-property-shorthands-getset":
                "Property shorthands of 'get' and 'set' are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-regexp-u-flag":
                "RegExp 'u' flag is not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-regexp-y-flag":
                "RegExp 'y' flag is not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-rest-parameters":
                "Rest parameters are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-spread-elements":
                "Spread elements are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-template-literals":
                "Template literals are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-unicode-codepoint-escapes":
                "Unicode code point escapes are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",

            //------------------------------------------------------------------
            // ES2016
            //------------------------------------------------------------------
            "no-exponential-operators":
                "Exponential operators are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",

            //------------------------------------------------------------------
            // ES2017
            //------------------------------------------------------------------
            "no-async-functions":
                "Async functions are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-trailing-function-commas":
                "Trailing commas in function syntax are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",

            //------------------------------------------------------------------
            // ES2018
            //------------------------------------------------------------------
            "no-async-iteration":
                "Async iteration is not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-malformed-template-literals":
                "Malformed template literals are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-regexp-lookbehind-assertions":
                "RegExp lookbehind assertions are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-regexp-named-capture-groups":
                "RegExp named capture groups are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-regexp-s-flag":
                "RegExp 's' flag is not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-regexp-unicode-property-escapes":
                "RegExp Unicode property escapes are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-rest-spread-properties":
                "Rest/spread properties are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",

            //------------------------------------------------------------------
            // ES2019
            //------------------------------------------------------------------
            "no-json-superset":
                "'\\u{{code}}' in string literals is not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-optional-catch-binding":
                "The omission of 'catch' binding is not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",

            //------------------------------------------------------------------
            // ES2020
            //------------------------------------------------------------------
            "no-bigint":
                "Bigint literals are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-bigint-property-names":
                "Bigint literal property names are not supported yet.",
            "no-dynamic-import":
                "'import()' expressions are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-optional-chaining":
                "Optional chainings are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
            "no-nullish-coalescing-operators":
                "Nullish coalescing operators are not supported until Node.js {{supported}}. The configured version range is '{{version}}'.",
        },
    },
    create(context) {
        return defineVisitor(context, parseOptions(context))
    },
}