libreccm-legacy/trunk-images/node_modules/tslint/lib/rules/strictBooleanExpressionsRul...

308 lines
15 KiB
JavaScript

/**
* @license
* Copyright 2016 Palantir Technologies, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
"use strict";
var __extends = (this && this.__extends) || (function () {
var extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
return function (d, b) {
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
Object.defineProperty(exports, "__esModule", { value: true });
var ts = require("typescript");
var Lint = require("../index");
var OPTION_ALLOW_NULL_UNION = "allow-null-union";
var OPTION_ALLOW_UNDEFINED_UNION = "allow-undefined-union";
var OPTION_ALLOW_STRING = "allow-string";
var OPTION_ALLOW_NUMBER = "allow-number";
var OPTION_ALLOW_MIX = "allow-mix";
// tslint:disable:switch-default
var Rule = (function (_super) {
__extends(Rule, _super);
function Rule() {
return _super !== null && _super.apply(this, arguments) || this;
}
/* tslint:enable:object-literal-sort-keys */
Rule.FAILURE_STRING = function (locationDescription, ty, isUnionType, expectedTypes) {
var expected = expectedTypes.length === 1
? "Only " + expectedTypes[0] + "s are allowed"
: "Allowed types are " + stringOr(expectedTypes);
return "This type is not allowed in the " + locationDescription + " because it " + this.tyFailure(ty, isUnionType) + ". " + expected + ".";
};
Rule.tyFailure = function (ty, isUnionType) {
var is = isUnionType ? "could be" : "is";
switch (ty) {
case 0 /* AlwaysTruthy */: return "is always truthy";
case 1 /* AlwaysFalsy */: return "is always falsy";
case 2 /* String */: return is + " a string";
case 3 /* Number */: return is + " a number";
case 4 /* Null */: return is + " null";
case 5 /* Undefined */: return is + " undefined";
case 6 /* Enum */: return is + " an enum";
case 7 /* Mixes */: return "unions more than one truthy/falsy type";
}
};
Rule.prototype.applyWithProgram = function (srcFile, langSvc) {
return this.applyWithWalker(new Walker(srcFile, this.getOptions(), langSvc.getProgram()));
};
return Rule;
}(Lint.Rules.TypedRule));
/* tslint:disable:object-literal-sort-keys */
Rule.metadata = {
ruleName: "strict-boolean-expressions",
description: (_a = ["\n Restricts the types allowed in boolean expressions. By default only booleans are allowed.\n\n The following nodes are checked:\n\n * Arguments to the `!`, `&&`, and `||` operators\n * The condition in a conditional expression (`cond ? x : y`)\n * Conditions for `if`, `for`, `while`, and `do-while` statements."], _a.raw = ["\n Restricts the types allowed in boolean expressions. By default only booleans are allowed.\n\n The following nodes are checked:\n\n * Arguments to the \\`!\\`, \\`&&\\`, and \\`||\\` operators\n * The condition in a conditional expression (\\`cond ? x : y\\`)\n * Conditions for \\`if\\`, \\`for\\`, \\`while\\`, and \\`do-while\\` statements."], Lint.Utils.dedent(_a)),
optionsDescription: (_b = ["\n These options may be provided:\n\n * `", "` allows union types containing `null`.\n - It does *not* allow `null` itself.\n * `", "` allows union types containing `undefined`.\n - It does *not* allow `undefined` itself.\n * `", "` allows strings.\n - It does *not* allow unions containing `string`.\n - It does *not* allow string literal types.\n * `", "` allows numbers.\n - It does *not* allow unions containing `number`.\n - It does *not* allow enums or number literal types.\n * `", "` allow multiple of the above to appear together.\n - For example, `string | number` or `RegExp | null | undefined` would normally not be allowed.\n - A type like `\"foo\" | \"bar\" | undefined` is always allowed, because it has only one way to be false."], _b.raw = ["\n These options may be provided:\n\n * \\`", "\\` allows union types containing \\`null\\`.\n - It does *not* allow \\`null\\` itself.\n * \\`", "\\` allows union types containing \\`undefined\\`.\n - It does *not* allow \\`undefined\\` itself.\n * \\`", "\\` allows strings.\n - It does *not* allow unions containing \\`string\\`.\n - It does *not* allow string literal types.\n * \\`", "\\` allows numbers.\n - It does *not* allow unions containing \\`number\\`.\n - It does *not* allow enums or number literal types.\n * \\`", "\\` allow multiple of the above to appear together.\n - For example, \\`string | number\\` or \\`RegExp | null | undefined\\` would normally not be allowed.\n - A type like \\`\"foo\" | \"bar\" | undefined\\` is always allowed, because it has only one way to be false."], Lint.Utils.dedent(_b, OPTION_ALLOW_NULL_UNION, OPTION_ALLOW_UNDEFINED_UNION, OPTION_ALLOW_STRING, OPTION_ALLOW_NUMBER, OPTION_ALLOW_MIX)),
options: {
type: "array",
items: {
type: "string",
enum: [OPTION_ALLOW_NULL_UNION, OPTION_ALLOW_UNDEFINED_UNION, OPTION_ALLOW_STRING, OPTION_ALLOW_NUMBER],
},
minLength: 0,
maxLength: 5,
},
optionExamples: [
"true",
"[true, " + OPTION_ALLOW_NULL_UNION + ", " + OPTION_ALLOW_UNDEFINED_UNION + ", " + OPTION_ALLOW_STRING + ", " + OPTION_ALLOW_NUMBER + "]",
],
type: "functionality",
typescriptOnly: true,
requiresTypeInfo: true,
};
exports.Rule = Rule;
var Walker = (function (_super) {
__extends(Walker, _super);
function Walker() {
var _this = _super !== null && _super.apply(this, arguments) || this;
_this.allowNullUnion = _this.hasOption(OPTION_ALLOW_NULL_UNION);
_this.allowUndefinedUnion = _this.hasOption(OPTION_ALLOW_UNDEFINED_UNION);
_this.allowString = _this.hasOption(OPTION_ALLOW_STRING);
_this.allowNumber = _this.hasOption(OPTION_ALLOW_NUMBER);
_this.allowMix = _this.hasOption(OPTION_ALLOW_MIX);
return _this;
}
Walker.prototype.visitBinaryExpression = function (node) {
var _this = this;
var op = binaryBooleanExpressionKind(node);
if (op !== undefined) {
var checkHalf = function (expr) {
// If it's another boolean binary expression, we'll check it when recursing.
if (!isBooleanBinaryExpression(expr)) {
_this.checkExpression(expr, "operand for the '" + op + "' operator");
}
};
checkHalf(node.left);
checkHalf(node.right);
}
_super.prototype.visitBinaryExpression.call(this, node);
};
Walker.prototype.visitPrefixUnaryExpression = function (node) {
if (node.operator === ts.SyntaxKind.ExclamationToken) {
this.checkExpression(node.operand, "operand for the '!' operator");
}
_super.prototype.visitPrefixUnaryExpression.call(this, node);
};
Walker.prototype.visitIfStatement = function (node) {
this.checkStatement(node, "'if' condition");
_super.prototype.visitIfStatement.call(this, node);
};
Walker.prototype.visitWhileStatement = function (node) {
this.checkStatement(node, "'while' condition");
_super.prototype.visitWhileStatement.call(this, node);
};
Walker.prototype.visitDoStatement = function (node) {
this.checkStatement(node, "'do-while' condition");
_super.prototype.visitDoStatement.call(this, node);
};
Walker.prototype.visitConditionalExpression = function (node) {
this.checkExpression(node.condition, "condition");
_super.prototype.visitConditionalExpression.call(this, node);
};
Walker.prototype.visitForStatement = function (node) {
if (node.condition !== undefined) {
this.checkExpression(node.condition, "'for' condition");
}
_super.prototype.visitForStatement.call(this, node);
};
Walker.prototype.checkStatement = function (node, locationDescription) {
// If it's a boolean binary expression, we'll check it when recursing.
if (!isBooleanBinaryExpression(node.expression)) {
this.checkExpression(node.expression, locationDescription);
}
};
Walker.prototype.checkExpression = function (node, locationDescription) {
var type = this.getTypeChecker().getTypeAtLocation(node);
var failure = this.getTypeFailure(type);
if (failure !== undefined) {
this.addFailureAtNode(node, Rule.FAILURE_STRING(locationDescription, failure, isUnionType(type), this.expectedTypes()));
}
};
Walker.prototype.getTypeFailure = function (type) {
if (isUnionType(type)) {
return this.handleUnion(type);
}
var kind = getKind(type);
var failure = this.failureForKind(kind, /*isInUnion*/ false);
if (failure !== undefined) {
return failure;
}
switch (triState(kind)) {
case true:
return 0 /* AlwaysTruthy */;
case false:
return 1 /* AlwaysFalsy */;
case undefined:
return undefined;
}
};
/** Fails if a kind of falsiness is not allowed. */
Walker.prototype.failureForKind = function (kind, isInUnion) {
switch (kind) {
case 0 /* String */:
case 1 /* FalseStringLiteral */:
return this.allowString ? undefined : 2 /* String */;
case 2 /* Number */:
case 3 /* FalseNumberLiteral */:
return this.allowNumber ? undefined : 3 /* Number */;
case 8 /* Enum */:
return 6 /* Enum */;
case 6 /* Null */:
return isInUnion && !this.allowNullUnion ? 4 /* Null */ : undefined;
case 7 /* Undefined */:
return isInUnion && !this.allowUndefinedUnion ? 5 /* Undefined */ : undefined;
default:
return undefined;
}
};
Walker.prototype.handleUnion = function (type) {
// Tracks whether it's possibly truthy.
var anyTruthy = false;
// Counts falsy kinds to see if there's a mix. Also tracks whether it's possibly falsy.
var seenFalsy = 0;
for (var _i = 0, _a = type.types; _i < _a.length; _i++) {
var ty = _a[_i];
var kind = getKind(ty);
var failure = this.failureForKind(kind, /*isInUnion*/ true);
if (failure !== undefined) {
return failure;
}
switch (triState(kind)) {
case true:
anyTruthy = true;
break;
case false:
seenFalsy++;
break;
default:
anyTruthy = true;
seenFalsy++;
}
}
return seenFalsy === 0 ? 0 /* AlwaysTruthy */
: !anyTruthy ? 1 /* AlwaysFalsy */
: !this.allowMix && seenFalsy > 1 ? 7 /* Mixes */ : undefined;
};
Walker.prototype.expectedTypes = function () {
var parts = ["boolean"];
if (this.allowNullUnion) {
parts.push("null-union");
}
if (this.allowUndefinedUnion) {
parts.push("undefined-union");
}
if (this.allowString) {
parts.push("string");
}
if (this.allowNumber) {
parts.push("number");
}
return parts;
};
return Walker;
}(Lint.ProgramAwareRuleWalker));
/** Divides a type into always true, always false, or unknown. */
function triState(kind) {
switch (kind) {
case 0 /* String */:
case 2 /* Number */:
case 4 /* Boolean */:
case 8 /* Enum */:
return undefined;
case 6 /* Null */:
case 7 /* Undefined */:
case 3 /* FalseNumberLiteral */:
case 1 /* FalseStringLiteral */:
case 5 /* FalseBooleanLiteral */:
return false;
case 9 /* AlwaysTruthy */:
return true;
}
}
function getKind(type) {
return is(ts.TypeFlags.String) ? 0 /* String */
: is(ts.TypeFlags.Number) ? 2 /* Number */
: is(ts.TypeFlags.Boolean) ? 4 /* Boolean */
: is(ts.TypeFlags.Null) ? 6 /* Null */
: is(ts.TypeFlags.Undefined | ts.TypeFlags.Void) ? 7 /* Undefined */ // tslint:disable-line:no-bitwise
: is(ts.TypeFlags.EnumLike) ? 8 /* Enum */
: is(ts.TypeFlags.NumberLiteral) ?
(type.text === "0" ? 3 /* FalseNumberLiteral */ : 9 /* AlwaysTruthy */)
: is(ts.TypeFlags.StringLiteral) ?
(type.text === "" ? 1 /* FalseStringLiteral */ : 9 /* AlwaysTruthy */)
: is(ts.TypeFlags.BooleanLiteral) ?
(type.intrinsicName === "true" ? 9 /* AlwaysTruthy */ : 5 /* FalseBooleanLiteral */)
: 9 /* AlwaysTruthy */;
function is(flags) {
return Lint.isTypeFlagSet(type, flags);
}
}
/** Matches `&&` and `||` operators. */
function isBooleanBinaryExpression(node) {
return node.kind === ts.SyntaxKind.BinaryExpression && binaryBooleanExpressionKind(node) !== undefined;
}
function binaryBooleanExpressionKind(node) {
switch (node.operatorToken.kind) {
case ts.SyntaxKind.AmpersandAmpersandToken:
return "&&";
case ts.SyntaxKind.BarBarToken:
return "||";
default:
return undefined;
}
}
function stringOr(parts) {
switch (parts.length) {
case 1:
return parts[0];
case 2:
return parts[0] + " or " + parts[1];
default:
var res = "";
for (var i = 0; i < parts.length - 1; i++) {
res += parts[i] + ", ";
}
return res + "or " + parts[parts.length - 1];
}
}
function isUnionType(type) {
return Lint.isTypeFlagSet(type, ts.TypeFlags.Union) && !Lint.isTypeFlagSet(type, ts.TypeFlags.Enum);
}
var _a, _b;