"use strict";
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    if (k2 === undefined) k2 = k;
    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
}) : (function(o, m, k, k2) {
    if (k2 === undefined) k2 = k;
    o[k2] = m[k];
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    Object.defineProperty(o, "default", { enumerable: true, value: v });
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    o["default"] = v;
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    if (mod && mod.__esModule) return mod;
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Object.defineProperty(exports, "__esModule", { value: true });
const experimental_utils_1 = require("@typescript-eslint/experimental-utils");
const tsutils = __importStar(require("tsutils"));
const ts = __importStar(require("typescript"));
const util = __importStar(require("../util"));
exports.default = util.createRule({
    name: 'strict-boolean-expressions',
    meta: {
        type: 'suggestion',
        fixable: 'code',
        docs: {
            description: 'Restricts the types allowed in boolean expressions',
            category: 'Best Practices',
            recommended: false,
            requiresTypeChecking: true,
        },
        schema: [
            {
                type: 'object',
                properties: {
                    allowString: { type: 'boolean' },
                    allowNumber: { type: 'boolean' },
                    allowNullableObject: { type: 'boolean' },
                    allowNullableBoolean: { type: 'boolean' },
                    allowNullableString: { type: 'boolean' },
                    allowNullableNumber: { type: 'boolean' },
                    allowAny: { type: 'boolean' },
                    allowRuleToRunWithoutStrictNullChecksIKnowWhatIAmDoing: {
                        type: 'boolean',
                    },
                },
                additionalProperties: false,
            },
        ],
        messages: {
            conditionErrorOther: 'Unexpected value in conditional. ' +
                'A boolean expression is required.',
            conditionErrorAny: 'Unexpected any value in conditional. ' +
                'An explicit comparison or type cast is required.',
            conditionErrorNullish: 'Unexpected nullish value in conditional. ' +
                'The condition is always false.',
            conditionErrorNullableBoolean: 'Unexpected nullable boolean value in conditional. ' +
                'Please handle the nullish case explicitly.',
            conditionErrorString: 'Unexpected string value in conditional. ' +
                'An explicit empty string check is required.',
            conditionErrorNullableString: 'Unexpected nullable string value in conditional. ' +
                'Please handle the nullish/empty cases explicitly.',
            conditionErrorNumber: 'Unexpected number value in conditional. ' +
                'An explicit zero/NaN check is required.',
            conditionErrorNullableNumber: 'Unexpected nullable number value in conditional. ' +
                'Please handle the nullish/zero/NaN cases explicitly.',
            conditionErrorObject: 'Unexpected object value in conditional. ' +
                'The condition is always true.',
            conditionErrorNullableObject: 'Unexpected nullable object value in conditional. ' +
                'An explicit null check is required.',
            noStrictNullCheck: 'This rule requires the `strictNullChecks` compiler option to be turned on to function correctly.',
            conditionFixDefaultFalse: 'Explicitly treat nullish value the same as false (`value ?? false`)',
            conditionFixDefaultEmptyString: 'Explicitly treat nullish value the same as an empty string (`value ?? ""`)',
            conditionFixDefaultZero: 'Explicitly treat nullish value the same as 0 (`value ?? 0`)',
            conditionFixCompareNullish: 'Change condition to check for null/undefined (`value != null`)',
            conditionFixCastBoolean: 'Explicitly cast value to a boolean (`Boolean(value)`)',
            conditionFixCompareTrue: 'Change condition to check if true (`value === true`)',
            conditionFixCompareFalse: 'Change condition to check if false (`value === false`)',
            conditionFixCompareStringLength: "Change condition to check string's length (`value.length !== 0`)",
            conditionFixCompareEmptyString: 'Change condition to check for empty string (`value !== ""`)',
            conditionFixCompareZero: 'Change condition to check for 0 (`value !== 0`)',
            conditionFixCompareNaN: 'Change condition to check for NaN (`!Number.isNaN(value)`)',
        },
    },
    defaultOptions: [
        {
            allowString: true,
            allowNumber: true,
            allowNullableObject: true,
            allowNullableBoolean: false,
            allowNullableString: false,
            allowNullableNumber: false,
            allowAny: false,
            allowRuleToRunWithoutStrictNullChecksIKnowWhatIAmDoing: false,
        },
    ],
    create(context, [options]) {
        const parserServices = util.getParserServices(context);
        const typeChecker = parserServices.program.getTypeChecker();
        const compilerOptions = parserServices.program.getCompilerOptions();
        const sourceCode = context.getSourceCode();
        const isStrictNullChecks = tsutils.isStrictCompilerOptionEnabled(compilerOptions, 'strictNullChecks');
        if (!isStrictNullChecks &&
            options.allowRuleToRunWithoutStrictNullChecksIKnowWhatIAmDoing !== true) {
            context.report({
                loc: {
                    start: { line: 0, column: 0 },
                    end: { line: 0, column: 0 },
                },
                messageId: 'noStrictNullCheck',
            });
        }
        const checkedNodes = new Set();
        return {
            ConditionalExpression: checkTestExpression,
            DoWhileStatement: checkTestExpression,
            ForStatement: checkTestExpression,
            IfStatement: checkTestExpression,
            WhileStatement: checkTestExpression,
            'LogicalExpression[operator!="??"]': checkNode,
            'UnaryExpression[operator="!"]': checkUnaryLogicalExpression,
        };
        function checkTestExpression(node) {
            if (node.test == null) {
                return;
            }
            checkNode(node.test, true);
        }
        function checkUnaryLogicalExpression(node) {
            checkNode(node.argument, true);
        }
        /**
         * This function analyzes the type of a node and checks if it is allowed in a boolean context.
         * It can recurse when checking nested logical operators, so that only the outermost operands are reported.
         * The right operand of a logical expression is ignored unless it's a part of a test expression (if/while/ternary/etc).
         * @param node The AST node to check.
         * @param isTestExpr Whether the node is a descendant of a test expression.
         */
        function checkNode(node, isTestExpr = false) {
            // prevent checking the same node multiple times
            if (checkedNodes.has(node)) {
                return;
            }
            checkedNodes.add(node);
            // for logical operator, we check its operands
            if (node.type === experimental_utils_1.AST_NODE_TYPES.LogicalExpression &&
                node.operator !== '??') {
                checkNode(node.left, isTestExpr);
                // we ignore the right operand when not in a context of a test expression
                if (isTestExpr) {
                    checkNode(node.right, isTestExpr);
                }
                return;
            }
            const tsNode = parserServices.esTreeNodeToTSNodeMap.get(node);
            const type = util.getConstrainedTypeAtLocation(typeChecker, tsNode);
            const types = inspectVariantTypes(tsutils.unionTypeParts(type));
            const is = (...wantedTypes) => types.size === wantedTypes.length &&
                wantedTypes.every(type => types.has(type));
            // boolean
            if (is('boolean')) {
                // boolean is always okay
                return;
            }
            // never
            if (is('never')) {
                // never is always okay
                return;
            }
            // nullish
            if (is('nullish')) {
                // condition is always false
                context.report({ node, messageId: 'conditionErrorNullish' });
                return;
            }
            // nullable boolean
            if (is('nullish', 'boolean')) {
                if (!options.allowNullableBoolean) {
                    if (isLogicalNegationExpression(node.parent)) {
                        // if (!nullableBoolean)
                        context.report({
                            node,
                            messageId: 'conditionErrorNullableBoolean',
                            suggest: [
                                {
                                    messageId: 'conditionFixDefaultFalse',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `${code} ?? false`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCompareFalse',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node: node.parent,
                                        innerNode: node,
                                        wrap: code => `${code} === false`,
                                    }),
                                },
                            ],
                        });
                    }
                    else {
                        // if (nullableBoolean)
                        context.report({
                            node,
                            messageId: 'conditionErrorNullableBoolean',
                            suggest: [
                                {
                                    messageId: 'conditionFixDefaultFalse',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `${code} ?? false`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCompareTrue',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `${code} === true`,
                                    }),
                                },
                            ],
                        });
                    }
                }
                return;
            }
            // Known edge case: truthy primitives and nullish values are always valid boolean expressions
            if ((options.allowNumber && is('nullish', 'truthy number')) ||
                (options.allowString && is('nullish', 'truthy string'))) {
                return;
            }
            // string
            if (is('string') || is('truthy string')) {
                if (!options.allowString) {
                    if (isLogicalNegationExpression(node.parent)) {
                        // if (!string)
                        context.report({
                            node,
                            messageId: 'conditionErrorString',
                            suggest: [
                                {
                                    messageId: 'conditionFixCompareStringLength',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node: node.parent,
                                        innerNode: node,
                                        wrap: code => `${code}.length === 0`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCompareEmptyString',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node: node.parent,
                                        innerNode: node,
                                        wrap: code => `${code} === ""`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCastBoolean',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node: node.parent,
                                        innerNode: node,
                                        wrap: code => `!Boolean(${code})`,
                                    }),
                                },
                            ],
                        });
                    }
                    else {
                        // if (string)
                        context.report({
                            node,
                            messageId: 'conditionErrorString',
                            suggest: [
                                {
                                    messageId: 'conditionFixCompareStringLength',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `${code}.length > 0`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCompareEmptyString',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `${code} !== ""`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCastBoolean',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `Boolean(${code})`,
                                    }),
                                },
                            ],
                        });
                    }
                }
                return;
            }
            // nullable string
            if (is('nullish', 'string')) {
                if (!options.allowNullableString) {
                    if (isLogicalNegationExpression(node.parent)) {
                        // if (!nullableString)
                        context.report({
                            node,
                            messageId: 'conditionErrorNullableString',
                            suggest: [
                                {
                                    messageId: 'conditionFixCompareNullish',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node: node.parent,
                                        innerNode: node,
                                        wrap: code => `${code} == null`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixDefaultEmptyString',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `${code} ?? ""`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCastBoolean',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node: node.parent,
                                        innerNode: node,
                                        wrap: code => `!Boolean(${code})`,
                                    }),
                                },
                            ],
                        });
                    }
                    else {
                        // if (nullableString)
                        context.report({
                            node,
                            messageId: 'conditionErrorNullableString',
                            suggest: [
                                {
                                    messageId: 'conditionFixCompareNullish',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `${code} != null`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixDefaultEmptyString',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `${code} ?? ""`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCastBoolean',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `Boolean(${code})`,
                                    }),
                                },
                            ],
                        });
                    }
                }
                return;
            }
            // number
            if (is('number') || is('truthy number')) {
                if (!options.allowNumber) {
                    if (isArrayLengthExpression(node, typeChecker, parserServices)) {
                        if (isLogicalNegationExpression(node.parent)) {
                            // if (!array.length)
                            context.report({
                                node,
                                messageId: 'conditionErrorNumber',
                                fix: util.getWrappingFixer({
                                    sourceCode,
                                    node: node.parent,
                                    innerNode: node,
                                    wrap: code => `${code} === 0`,
                                }),
                            });
                        }
                        else {
                            // if (array.length)
                            context.report({
                                node,
                                messageId: 'conditionErrorNumber',
                                fix: util.getWrappingFixer({
                                    sourceCode,
                                    node,
                                    wrap: code => `${code} > 0`,
                                }),
                            });
                        }
                    }
                    else if (isLogicalNegationExpression(node.parent)) {
                        // if (!number)
                        context.report({
                            node,
                            messageId: 'conditionErrorNumber',
                            suggest: [
                                {
                                    messageId: 'conditionFixCompareZero',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node: node.parent,
                                        innerNode: node,
                                        // TODO: we have to compare to 0n if the type is bigint
                                        wrap: code => `${code} === 0`,
                                    }),
                                },
                                {
                                    // TODO: don't suggest this for bigint because it can't be NaN
                                    messageId: 'conditionFixCompareNaN',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node: node.parent,
                                        innerNode: node,
                                        wrap: code => `Number.isNaN(${code})`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCastBoolean',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node: node.parent,
                                        innerNode: node,
                                        wrap: code => `!Boolean(${code})`,
                                    }),
                                },
                            ],
                        });
                    }
                    else {
                        // if (number)
                        context.report({
                            node,
                            messageId: 'conditionErrorNumber',
                            suggest: [
                                {
                                    messageId: 'conditionFixCompareZero',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `${code} !== 0`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCompareNaN',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `!Number.isNaN(${code})`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCastBoolean',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `Boolean(${code})`,
                                    }),
                                },
                            ],
                        });
                    }
                }
                return;
            }
            // nullable number
            if (is('nullish', 'number')) {
                if (!options.allowNullableNumber) {
                    if (isLogicalNegationExpression(node.parent)) {
                        // if (!nullableNumber)
                        context.report({
                            node,
                            messageId: 'conditionErrorNullableNumber',
                            suggest: [
                                {
                                    messageId: 'conditionFixCompareNullish',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node: node.parent,
                                        innerNode: node,
                                        wrap: code => `${code} == null`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixDefaultZero',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `${code} ?? 0`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCastBoolean',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node: node.parent,
                                        innerNode: node,
                                        wrap: code => `!Boolean(${code})`,
                                    }),
                                },
                            ],
                        });
                    }
                    else {
                        // if (nullableNumber)
                        context.report({
                            node,
                            messageId: 'conditionErrorNullableNumber',
                            suggest: [
                                {
                                    messageId: 'conditionFixCompareNullish',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `${code} != null`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixDefaultZero',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `${code} ?? 0`,
                                    }),
                                },
                                {
                                    messageId: 'conditionFixCastBoolean',
                                    fix: util.getWrappingFixer({
                                        sourceCode,
                                        node,
                                        wrap: code => `Boolean(${code})`,
                                    }),
                                },
                            ],
                        });
                    }
                }
                return;
            }
            // object
            if (is('object')) {
                // condition is always true
                context.report({ node, messageId: 'conditionErrorObject' });
                return;
            }
            // nullable object
            if (is('nullish', 'object')) {
                if (!options.allowNullableObject) {
                    if (isLogicalNegationExpression(node.parent)) {
                        // if (!nullableObject)
                        context.report({
                            node,
                            messageId: 'conditionErrorNullableObject',
                            fix: util.getWrappingFixer({
                                sourceCode,
                                node: node.parent,
                                innerNode: node,
                                wrap: code => `${code} == null`,
                            }),
                        });
                    }
                    else {
                        // if (nullableObject)
                        context.report({
                            node,
                            messageId: 'conditionErrorNullableObject',
                            fix: util.getWrappingFixer({
                                sourceCode,
                                node,
                                wrap: code => `${code} != null`,
                            }),
                        });
                    }
                }
                return;
            }
            // any
            if (is('any')) {
                if (!options.allowAny) {
                    context.report({
                        node,
                        messageId: 'conditionErrorAny',
                        suggest: [
                            {
                                messageId: 'conditionFixCastBoolean',
                                fix: util.getWrappingFixer({
                                    sourceCode,
                                    node,
                                    wrap: code => `Boolean(${code})`,
                                }),
                            },
                        ],
                    });
                }
                return;
            }
            // other
            context.report({ node, messageId: 'conditionErrorOther' });
        }
        /**
         * Check union variants for the types we care about
         */
        function inspectVariantTypes(types) {
            const variantTypes = new Set();
            if (types.some(type => tsutils.isTypeFlagSet(type, ts.TypeFlags.Null | ts.TypeFlags.Undefined | ts.TypeFlags.VoidLike))) {
                variantTypes.add('nullish');
            }
            if (types.some(type => tsutils.isTypeFlagSet(type, ts.TypeFlags.BooleanLike))) {
                variantTypes.add('boolean');
            }
            const strings = types.filter(type => tsutils.isTypeFlagSet(type, ts.TypeFlags.StringLike));
            if (strings.length) {
                if (strings.some(type => type.isStringLiteral() && type.value !== '')) {
                    variantTypes.add('truthy string');
                }
                else {
                    variantTypes.add('string');
                }
            }
            const numbers = types.filter(type => tsutils.isTypeFlagSet(type, ts.TypeFlags.NumberLike | ts.TypeFlags.BigIntLike));
            if (numbers.length) {
                if (numbers.some(type => type.isNumberLiteral() && type.value !== 0)) {
                    variantTypes.add('truthy number');
                }
                else {
                    variantTypes.add('number');
                }
            }
            if (types.some(type => !tsutils.isTypeFlagSet(type, ts.TypeFlags.Null |
                ts.TypeFlags.Undefined |
                ts.TypeFlags.VoidLike |
                ts.TypeFlags.BooleanLike |
                ts.TypeFlags.StringLike |
                ts.TypeFlags.NumberLike |
                ts.TypeFlags.BigIntLike |
                ts.TypeFlags.Any |
                ts.TypeFlags.Unknown |
                ts.TypeFlags.Never))) {
                variantTypes.add('object');
            }
            if (types.some(type => util.isTypeAnyType(type) || util.isTypeUnknownType(type))) {
                variantTypes.add('any');
            }
            if (types.some(type => tsutils.isTypeFlagSet(type, ts.TypeFlags.Never))) {
                variantTypes.add('never');
            }
            return variantTypes;
        }
    },
});
function isLogicalNegationExpression(node) {
    return node.type === experimental_utils_1.AST_NODE_TYPES.UnaryExpression && node.operator === '!';
}
function isArrayLengthExpression(node, typeChecker, parserServices) {
    if (node.type !== experimental_utils_1.AST_NODE_TYPES.MemberExpression) {
        return false;
    }
    if (node.computed) {
        return false;
    }
    if (node.property.name !== 'length') {
        return false;
    }
    const objectTsNode = parserServices.esTreeNodeToTSNodeMap.get(node.object);
    const objectType = util.getConstrainedTypeAtLocation(typeChecker, objectTsNode);
    return util.isTypeArrayTypeOrUnionOfArrayTypes(objectType, typeChecker);
}
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