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"use strict" ;
/ * *
* @ license
* Copyright 2017 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 .
* /
Object . defineProperty ( exports , "__esModule" , { value : true } ) ;
var tslib _1 = require ( "tslib" ) ;
var utils = require ( "tsutils" ) ;
var ts = require ( "typescript" ) ;
var Lint = require ( "../index" ) ;
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var Rule = /** @class */ ( function ( _super ) {
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tslib _1 . _ _extends ( Rule , _super ) ;
function Rule ( ) {
return _super !== null && _super . apply ( this , arguments ) || this ;
}
/* tslint:enable:object-literal-sort-keys */
Rule . FAILURE _STRING = function ( negate ) {
return "This expression is unnecessarily compared to a boolean. Just " + ( negate ? "negate it" : "use it directly" ) + "." ;
} ;
Rule . prototype . applyWithProgram = function ( sourceFile , program ) {
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return this . applyWithFunction ( sourceFile , walk , undefined , program . getTypeChecker ( ) ) ;
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} ;
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/* tslint:disable:object-literal-sort-keys */
Rule . metadata = {
ruleName : "no-boolean-literal-compare" ,
description : "Warns on comparison to a boolean literal, as in `x === true`." ,
hasFix : true ,
optionsDescription : "Not configurable." ,
options : null ,
optionExamples : [ true ] ,
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rationale : Lint . Utils . dedent ( templateObject _1 || ( templateObject _1 = tslib _1 . _ _makeTemplateObject ( [ "\n Comparing boolean values to boolean literals is unnecessary, as those expressions will result in booleans too.\n Just use the boolean values directly or negate them.\n " ] , [ "\n Comparing boolean values to boolean literals is unnecessary, as those expressions will result in booleans too.\n Just use the boolean values directly or negate them.\n " ] ) ) ) ,
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type : "style" ,
typescriptOnly : true ,
requiresTypeInfo : true ,
} ;
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return Rule ;
} ( Lint . Rules . TypedRule ) ) ;
exports . Rule = Rule ;
function walk ( ctx , checker ) {
return ts . forEachChild ( ctx . sourceFile , function cb ( node ) {
if ( utils . isBinaryExpression ( node ) ) {
var cmp = getBooleanComparison ( node , checker ) ;
if ( cmp !== undefined ) {
ctx . addFailureAtNode ( cmp . expression , Rule . FAILURE _STRING ( cmp . negate ) , fix ( node , cmp ) ) ;
}
}
return ts . forEachChild ( node , cb ) ;
} ) ;
}
function getBooleanComparison ( node , checker ) {
var cmp = deconstructComparison ( node ) ;
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return cmp === undefined || ! utils . isTypeFlagSet ( checker . getTypeAtLocation ( cmp . expression ) , ts . TypeFlags . Boolean ) ? undefined : cmp ;
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}
function fix ( node , _a ) {
var negate = _a . negate , expression = _a . expression ;
var deleted = node . left === expression
? Lint . Replacement . deleteFromTo ( node . left . end , node . end )
: Lint . Replacement . deleteFromTo ( node . getStart ( ) , node . right . getStart ( ) ) ;
if ( ! negate ) {
return deleted ;
}
else if ( needsParenthesesForNegate ( expression ) ) {
return [
deleted ,
Lint . Replacement . appendText ( node . getStart ( ) , "!(" ) ,
Lint . Replacement . appendText ( node . getEnd ( ) , ")" ) ,
] ;
}
else {
return [
deleted ,
Lint . Replacement . appendText ( node . getStart ( ) , "!" ) ,
] ;
}
}
function needsParenthesesForNegate ( node ) {
switch ( node . kind ) {
case ts . SyntaxKind . AsExpression :
case ts . SyntaxKind . BinaryExpression :
return true ;
default :
return false ;
}
}
function deconstructComparison ( node ) {
var left = node . left , operatorToken = node . operatorToken , right = node . right ;
var eq = Lint . getEqualsKind ( operatorToken ) ;
if ( eq === undefined ) {
return undefined ;
}
var leftValue = booleanFromExpression ( left ) ;
if ( leftValue !== undefined ) {
return { negate : leftValue !== eq . isPositive , expression : right } ;
}
var rightValue = booleanFromExpression ( right ) ;
if ( rightValue !== undefined ) {
return { negate : rightValue !== eq . isPositive , expression : left } ;
}
return undefined ;
}
function booleanFromExpression ( node ) {
switch ( node . kind ) {
case ts . SyntaxKind . TrueKeyword :
return true ;
case ts . SyntaxKind . FalseKeyword :
return false ;
default :
return undefined ;
}
}
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var templateObject _1 ;