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/* Any copyright is dedicated to the Public Domain.
"use strict";
// ------------------------------------------------------------------------------
// Requirements
// ------------------------------------------------------------------------------
var rule = require("../lib/rules/prefer-boolean-length-check");
var RuleTester = require("eslint").RuleTester;
const ruleTester = new RuleTester({ parserOptions: { ecmaVersion: "latest" } });
// ------------------------------------------------------------------------------
// Tests
// ------------------------------------------------------------------------------
function invalidError() {
return [{ messageId: "preferBooleanCheck", type: "BinaryExpression" }];
}
ruleTester.run("check-length", rule, {
valid: [
"if (foo.length && foo.length) {}",
"if (!foo.length) {}",
"if (foo.value == 0) {}",
"if (foo.value > 0) {}",
"if (0 == foo.value) {}",
"if (0 < foo.value) {}",
"var a = !!foo.length",
"function bar() { return !!foo.length }",
],
invalid: [
{
code: "if (foo.length == 0) {}",
output: "if (!foo.length) {}",
errors: invalidError(),
},
{
code: "if (foo.length > 0) {}",
output: "if (foo.length) {}",
errors: invalidError(),
},
{
code: "if (0 < foo.length) {}",
output: "if (foo.length) {}",
errors: invalidError(),
},
{
code: "if (0 == foo.length) {}",
output: "if (!foo.length) {}",
errors: invalidError(),
},
{
code: "if (foo && foo.length == 0) {}",
output: "if (foo && !foo.length) {}",
errors: invalidError(),
},
{
code: "if (foo.bar.length == 0) {}",
output: "if (!foo.bar.length) {}",
errors: invalidError(),
},
{
code: "var a = foo.length>0",
output: "var a = !!foo.length",
errors: invalidError(),
},
{
code: "function bar() { return foo.length>0 }",
output: "function bar() { return !!foo.length }",
errors: invalidError(),
},
{
code: "if (foo && bar.length>0) {}",
output: "if (foo && bar.length) {}",
errors: invalidError(),
},
{
code: "while (foo && bar.length>0) {}",
output: "while (foo && bar.length) {}",
errors: invalidError(),
},
{
code: "x = y && bar.length > 0",
output: "x = y && !!bar.length",
errors: invalidError(),
},
{
code: "function bar() { return x && foo.length > 0}",
output: "function bar() { return x && !!foo.length}",
errors: invalidError(),
},
],
});