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/**
* @license Apache-2.0
*
* Copyright (c) 2018 The Stdlib Authors.
*
* 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';
// MODULES //
var tape = require( 'tape' );
var removeFirst = require( './../lib' );
// TESTS //
tape( 'main export is a function', function test( t ) {
t.ok( true, __filename );
t.strictEqual( typeof removeFirst, 'function', 'main export is a function' );
t.end();
});
tape( 'the function throws an error if not provided a string', function test( t ) {
var values;
var i;
values = [
5,
null,
true,
void 0,
NaN,
[],
{},
function noop() {}
];
for ( i = 0; i < values.length; i++ ) {
t.throws( badValue( values[i] ), TypeError, 'throws an error when provided '+values[i] );
}
t.end();
function badValue( value ) {
return function badValue() {
removeFirst( value );
};
}
});
tape( 'the function throws an error if provided a second argument which is not a nonnegative integer', function test( t ) {
var values;
var i;
values = [
'abc',
3.14,
null,
true,
void 0,
NaN,
[],
{},
function noop() {}
];
for ( i = 0; i < values.length; i++ ) {
t.throws( badValue( values[i] ), TypeError, 'throws an error when provided '+values[i] );
}
t.end();
function badValue( value ) {
return function badValue() {
removeFirst( 'beep', value );
};
}
});
tape( 'the function returns an empty string if provided an empty string', function test( t ) {
t.strictEqual( removeFirst( '' ), '', 'returns empty string' );
t.end();
});
tape( 'the function removes the first character of a given string', function test( t ) {
var out;
out = removeFirst( 'hello world' );
t.strictEqual( out, 'ello world', 'removes first character' );
out = removeFirst( '!!!' );
t.strictEqual( out, '!!', 'removes character' );
out = removeFirst( 'Hello World' );
t.strictEqual( out, 'ello World', 'removes character' );
out = removeFirst( 'अनुच्छेद' );
t.strictEqual( out, 'नुच्छेद', 'returns expected value' );
out = removeFirst( '六书/六書' );
t.strictEqual( out, '书/六書', 'returns expected value' );
out = removeFirst( '🌷' );
t.strictEqual( out, '', 'returns expected value' );
t.end();
});
tape( 'the function returns the original string if provided zero as the second argument', function test( t ) {
var out;
out = removeFirst( 'hello world', 0 );
t.strictEqual( out, 'hello world', 'returns original string' );
t.end();
});
tape( 'the function removes the first `n` characters of a given string if provided a second argument', function test( t ) {
var out;
out = removeFirst( 'hello world', 1 );
t.strictEqual( out, 'ello world', 'removes first character' );
out = removeFirst( 'hello world', 6 );
t.strictEqual( out, 'world', 'returns expected value' );
out = removeFirst( '!!!', 1 );
t.strictEqual( out, '!!', 'removes character' );
out = removeFirst( '!!!', 2 );
t.strictEqual( out, '!', 'removes character' );
out = removeFirst( 'अनुच्छेद', 1 );
t.strictEqual( out, 'नुच्छेद', 'returns expected value' );
out = removeFirst( '六书/六書', 1 );
t.strictEqual( out, '书/六書', 'returns expected value' );
out = removeFirst( '🌷', 1 );
t.strictEqual( out, '', 'returns expected value' );
t.end();
});
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