CSSMinTest.php

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<?php
 
use Wikimedia\TestingAccessWrapper;
 
class CSSMinTest extends MediaWikiTestCase {
 
    protected function setUp() {
        parent::setUp();
 
        // For wfExpandUrl
        $server = 'https://expand.example';
        $this->setMwGlobals( [
            'wgServer' => $server,
            'wgCanonicalServer' => $server,
        ] );
    }
 
    public function testGetLocalFileReferences( $input, $expected ) {
        $output = CSSMin::getLocalFileReferences( $input, '/' );
        $this->assertEquals(
            $expected,
            $output,
            'getLocalFileReferences() must find the local file properly'
        );
    }
 
    public static function providesReferencedFiles() {
        // input, array of expected local file names
        return [
            [ 'url("//example.org")', [] ],
            [ 'url("https://example.org")', [] ],
            [ 'url("#default#")', [] ],
            [ 'url("WikiFont-Glyphs.svg#wikiglyph")', [ '/WikiFont-Glyphs.svg' ] ],
            [ 'url("#some-anchor")', [] ],
        ];
    }
 
    public function testSerializeStringValue( $input, $expected ) {
        $output = CSSMin::serializeStringValue( $input );
        $this->assertEquals(
            $expected,
            $output,
            'Serialized output must be in the expected form.'
        );
    }
 
    public static function provideSerializeStringValue() {
        return [
            [ 'Hello World!', '"Hello World!"' ],
            [ "Null\0Null", "\"Null\\fffd Null\"" ],
            [ '"', '"\\""' ],
            [ "'", '"\'"' ],
            [ "\\", '"\\\\"' ],
            [ "Tab\tTab", '"Tab\\9 Tab"' ],
            [ "Space  tab \t space", '"Space  tab \\9  space"' ],
            [ "Line\nfeed", '"Line\\a feed"' ],
            [ "Return\rreturn", '"Return\\d return"' ],
            [ "Next\xc2\x85line", "\"Next\xc2\x85line\"" ],
            [ "Del\x7fDel", '"Del\\7f Del"' ],
            [ "nb\xc2\xa0sp", "\"nb\xc2\xa0sp\"" ],
            [ "AMP&amp;AMP", "\"AMP&amp;AMP\"" ],
            [ '!"#$%&\'()*+,-./0123456789:;<=>?', '"!\\"#$%&\'()*+,-./0123456789:;<=>?"' ],
            [ '@[\\]^_`{|}~', '"@[\\\\]^_`{|}~"' ],
            [ 'ä', '"ä"' ],
            [ 'Ä', '"Ä"' ],
            [ '€', '"€"' ],
            [ '𝒞', '"𝒞"' ], // U+1D49E 'MATHEMATICAL SCRIPT CAPITAL C'
        ];
    }
 
    public function testGetMimeType( $fileContents, $fileExtension, $expected ) {
        $fileName = wfTempDir() . DIRECTORY_SEPARATOR . uniqid( 'MW_PHPUnit_CSSMinTest_' ) . '.'
            . $fileExtension;
        $this->addTmpFiles( $fileName );
        file_put_contents( $fileName, $fileContents );
        $this->assertSame( $expected, CSSMin::getMimeType( $fileName ) );
    }
 
    public static function provideMimeType() {
        return [
            'JPEG with short extension' => [
                "\xFF\xD8\xFF",
                'jpg',
                'image/jpeg'
            ],
            'JPEG with long extension' => [
                "\xFF\xD8\xFF",
                'jpeg',
                'image/jpeg'
            ],
            'PNG' => [
                "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A",
                'png',
                'image/png'
            ],
 
            'PNG extension but JPEG content' => [
                "\xFF\xD8\xFF",
                'png',
                'image/png'
            ],
            'JPEG extension but PNG content' => [
                "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A",
                'jpg',
                'image/jpeg'
            ],
            'PNG extension but SVG content' => [
                '<?xml version="1.0"?><svg></svg>',
                'png',
                'image/png'
            ],
            'SVG extension but PNG content' => [
                "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A",
                'svg',
                'image/svg+xml'
            ],
 
            'SVG with all headers' => [
                '<?xml version="1.0"?><!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" '
                . '"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"><svg></svg>',
                'svg',
                'image/svg+xml'
            ],
            'SVG with XML header only' => [
                '<?xml version="1.0"?><svg></svg>',
                'svg',
                'image/svg+xml'
            ],
            'SVG with DOCTYPE only' => [
                '<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" '
                . '"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"><svg></svg>',
                'svg',
                'image/svg+xml'
            ],
            'SVG without any header' => [
                '<svg></svg>',
                'svg',
                'image/svg+xml'
            ],
        ];
    }
 
    public function testMinify( $code, $expectedOutput ) {
        $minified = CSSMin::minify( $code );
 
        $this->assertEquals(
            $expectedOutput,
            $minified,
            'Minified output should be in the form expected.'
        );
    }
 
    public static function provideMinifyCases() {
        return [
            // Whitespace
            [ "\r\t\f \v\n\r", "" ],
            [ "foo, bar {\n\tprop: value;\n}", "foo,bar{prop:value}" ],
 
            // Loose comments
            [ "/* foo */", "" ],
            [ "/*******\n foo\n *******/", "" ],
            [ "/*!\n foo\n */", "" ],
 
            // Inline comments in various different places
            [ "/* comment */foo, bar {\n\tprop: value;\n}", "foo,bar{prop:value}" ],
            [ "foo/* comment */, bar {\n\tprop: value;\n}", "foo,bar{prop:value}" ],
            [ "foo,/* comment */ bar {\n\tprop: value;\n}", "foo,bar{prop:value}" ],
            [ "foo, bar/* comment */ {\n\tprop: value;\n}", "foo,bar{prop:value}" ],
            [ "foo, bar {\n\t/* comment */prop: value;\n}", "foo,bar{prop:value}" ],
            [ "foo, bar {\n\tprop: /* comment */value;\n}", "foo,bar{prop:value}" ],
            [ "foo, bar {\n\tprop: value /* comment */;\n}", "foo,bar{prop:value }" ],
            [ "foo, bar {\n\tprop: value; /* comment */\n}", "foo,bar{prop:value; }" ],
 
            // Keep track of things that aren't as minified as much as they
            // could be (T37493)
            [ 'foo { prop: value ;}', 'foo{prop:value }' ],
            [ 'foo { prop : value; }', 'foo{prop :value}' ],
            [ 'foo { prop: value ; }', 'foo{prop:value }' ],
            [ 'foo { font-family: "foo" , "bar"; }', 'foo{font-family:"foo" ,"bar"}' ],
            [ "foo { src:\n\turl('foo') ,\n\turl('bar') ; }", "foo{src:url('foo') ,url('bar') }" ],
 
            // Interesting cases with string values
            // - Double quotes, single quotes
            [ 'foo { content: ""; }', 'foo{content:""}' ],
            [ "foo { content: ''; }", "foo{content:''}" ],
            [ 'foo { content: "\'"; }', 'foo{content:"\'"}' ],
            [ "foo { content: '\"'; }", "foo{content:'\"'}" ],
            // - Whitespace in string values
            [ 'foo { content: " "; }', 'foo{content:" "}' ],
 
            // Whitespaces after opening and before closing parentheses and brackets
            [ 'a:not( [ href ] ) { prop: url( foobar.png ); }', 'a:not([href]){prop:url(foobar.png)}' ],
 
            // Ensure that the invalid "url (" will not become the valid "url(" by minification
            [ 'foo { prop: url ( foobar.png ); }', 'foo{prop:url (foobar.png)}' ],
        ];
    }
 
    public static function provideIsRemoteUrl() {
        return [
            [ true, 'http://localhost/w/red.gif?123' ],
            [ true, 'https://example.org/x.png' ],
            [ true, '//example.org/x.y.z/image.png' ],
            [ true, '//localhost/styles.css?query=yes' ],
            [ true, 'data:image/gif;base64,R0lGODlhAQABAIAAAP8AADAAACwAAAAAAQABAAACAkQBADs=' ],
            [ false, 'x.gif' ],
            [ false, '/x.gif' ],
            [ false, './x.gif' ],
            [ false, '../x.gif' ],
        ];
    }
 
    public function testIsRemoteUrl( $expect, $url ) {
        $class = TestingAccessWrapper::newFromClass( CSSMin::class );
        $this->assertEquals( $class->isRemoteUrl( $url ), $expect );
    }
 
    public static function provideIsLocalUrls() {
        return [
            [ false, 'x.gif' ],
            [ true, '/x.gif' ],
            [ false, './x.gif' ],
            [ false, '../x.gif' ],
        ];
    }
 
    public function testIsLocalUrl( $expect, $url ) {
        $class = TestingAccessWrapper::newFromClass( CSSMin::class );
        $this->assertEquals( $class->isLocalUrl( $url ), $expect );
    }
 
    public function testRemap( $message, $params, $expectedOutput ) {
        $remapped = call_user_func_array( 'CSSMin::remap', $params );
 
        $messageAdd = " Case: $message";
        $this->assertEquals(
            $expectedOutput,
            $remapped,
            'CSSMin::remap should return the expected url form.' . $messageAdd
        );
    }
 
    public static function provideRemapCases() {
        // Parameter signature:
        // CSSMin::remap( $code, $local, $remote, $embedData = true )
        return [
            [
                'Simple case',
                [ 'foo { prop: url(bar.png); }', false, 'http://example.org', false ],
                'foo { prop: url(http://example.org/bar.png); }',
            ],
            [
                'Without trailing slash',
                [ 'foo { prop: url(../bar.png); }', false, 'http://example.org/quux', false ],
                'foo { prop: url(http://example.org/bar.png); }',
            ],
            [
                'With trailing slash on remote (T29052)',
                [ 'foo { prop: url(../bar.png); }', false, 'http://example.org/quux/', false ],
                'foo { prop: url(http://example.org/bar.png); }',
            ],
            [
                'Guard against stripping double slashes from query',
                [ 'foo { prop: url(bar.png?corge=//grault); }', false, 'http://example.org/quux/', false ],
                'foo { prop: url(http://example.org/quux/bar.png?corge=//grault); }',
            ],
            [
                'Expand absolute paths',
                [ 'foo { prop: url(/w/skin/images/bar.png); }', false, 'http://example.org/quux', false ],
                'foo { prop: url(https://expand.example/w/skin/images/bar.png); }',
            ],
            [
                "Don't barf at behavior: url(#default#behaviorName) - T162973",
                [ 'foo { behavior: url(#default#bar); }', false, '/w/', false ],
                'foo { behavior: url("#default#bar"); }',
            ],
            [
                'Keeps anchors',
                [ 'url(#other)', false, '/', false ],
                'url("#other")'
            ],
            [
                'Keeps anchors after a path',
                [ 'url(images/file.svg#id)', false, '/', false ],
                'url("/images/file.svg#id")'
            ],
        ];
    }
 
    public function testRemapEmptyUrl( $params, $expected ) {
        $remapped = call_user_func_array( 'CSSMin::remap', $params );
        $this->assertEquals( $expected, $remapped, 'Ignore empty url' );
    }
 
    public static function provideRemapEmptyUrl() {
        return [
            'Empty' => [
                [ "background-image: url();", false, '/example', false ],
                "background-image: url();",
            ],
            'Single quote' => [
                [ "background-image: url('');", false, '/example', false ],
                "background-image: url('');",
            ],
            'Double quote' => [
                [ 'background-image: url("");', false, '/example', false ],
                'background-image: url("");',
            ],
        ];
    }
 
    public function testRemapRemapping( $message, $input, $expectedOutput ) {
        $localPath = __DIR__ . '/../../data/cssmin';
        $remotePath = 'http://localhost/w';
 
        $realOutput = CSSMin::remap( $input, $localPath, $remotePath );
        $this->assertEquals( $expectedOutput, $realOutput, "CSSMin::remap: $message" );
    }
 
    public static function provideRemapRemappingCases() {
        // red.gif and green.gif are one-pixel 35-byte GIFs.
        // large.png is a 35K PNG that should be non-embeddable.
        // Full paths start with http://localhost/w/.
        // Timestamps in output are replaced with 'timestamp'.
 
        // data: URIs for red.gif, green.gif, circle.svg
        $red   = 'data:image/gif;base64,R0lGODlhAQABAIAAAP8AADAAACwAAAAAAQABAAACAkQBADs=';
        $green = 'data:image/gif;base64,R0lGODlhAQABAIAAAACAADAAACwAAAAAAQABAAACAkQBADs=';
        $svg = 'data:image/svg+xml,%3Csvg xmlns=%22http://www.w3.org/2000/svg%22 width=%228'
            . '%22 height=%228%22 viewBox=%220 0 8 8%22%3E %3Ccircle cx=%224%22 cy=%224%22 '
            . 'r=%222%22/%3E %3Ca xmlns:xlink=%22http://www.w3.org/1999/xlink%22 xlink:title='
            . '%22%3F%3E%22%3Etest%3C/a%3E %3C/svg%3E';
 
        // phpcs:disable Generic.Files.LineLength
        return [
            [
                'Regular file',
                'foo { background: url(red.gif); }',
                'foo { background: url(http://localhost/w/red.gif?34ac6); }',
            ],
            [
                'Regular file (missing)',
                'foo { background: url(theColorOfHerHair.gif); }',
                'foo { background: url(http://localhost/w/theColorOfHerHair.gif); }',
            ],
            [
                'Remote URL',
                'foo { background: url(http://example.org/w/foo.png); }',
                'foo { background: url(http://example.org/w/foo.png); }',
            ],
            [
                'Protocol-relative remote URL',
                'foo { background: url(//example.org/w/foo.png); }',
                'foo { background: url(//example.org/w/foo.png); }',
            ],
            [
                'Remote URL with query',
                'foo { background: url(http://example.org/w/foo.png?query=yes); }',
                'foo { background: url(http://example.org/w/foo.png?query=yes); }',
            ],
            [
                'Protocol-relative remote URL with query',
                'foo { background: url(//example.org/w/foo.png?query=yes); }',
                'foo { background: url(//example.org/w/foo.png?query=yes); }',
            ],
            [
                'Domain-relative URL',
                'foo { background: url(/static/foo.png); }',
                'foo { background: url(https://expand.example/static/foo.png); }',
            ],
            [
                'Domain-relative URL with query',
                'foo { background: url(/static/foo.png?query=yes); }',
                'foo { background: url(https://expand.example/static/foo.png?query=yes); }',
            ],
            [
                'Remote URL (unnecessary quotes not preserved)',
                'foo { background: url("http://example.org/w/unnecessary-quotes.png"); }',
                'foo { background: url(http://example.org/w/unnecessary-quotes.png); }',
            ],
            [
                'Embedded file',
                'foo { /* @embed */ background: url(red.gif); }',
                "foo { background: url($red); background: url(http://localhost/w/red.gif?34ac6)!ie; }",
            ],
            [
                'Embedded file, other comments before the rule',
                "foo { /* Bar. */ /* @embed */ background: url(red.gif); }",
                "foo { /* Bar. */ background: url($red); /* Bar. */ background: url(http://localhost/w/red.gif?34ac6)!ie; }",
            ],
            [
                'Can not re-embed data: URIs',
                "foo { /* @embed */ background: url($red); }",
                "foo { background: url($red); }",
            ],
            [
                'Can not remap data: URIs',
                "foo { background: url($red); }",
                "foo { background: url($red); }",
            ],
            [
                'Can not embed remote URLs',
                'foo { /* @embed */ background: url(http://example.org/w/foo.png); }',
                'foo { background: url(http://example.org/w/foo.png); }',
            ],
            [
                'Embedded file (inline @embed)',
                'foo { background: /* @embed */ url(red.gif); }',
                "foo { background: url($red); "
                    . "background: url(http://localhost/w/red.gif?34ac6)!ie; }",
            ],
            [
                'Can not embed large files',
                'foo { /* @embed */ background: url(large.png); }',
                "foo { background: url(http://localhost/w/large.png?e3d1f); }",
            ],
            [
                'SVG files are embedded without base64 encoding and unnecessary IE 6 and 7 fallback',
                'foo { /* @embed */ background: url(circle.svg); }',
                "foo { background: url(\"$svg\"); }",
            ],
            [
                'Two regular files in one rule',
                'foo { background: url(red.gif), url(green.gif); }',
                'foo { background: url(http://localhost/w/red.gif?34ac6), '
                    . 'url(http://localhost/w/green.gif?13651); }',
            ],
            [
                'Two embedded files in one rule',
                'foo { /* @embed */ background: url(red.gif), url(green.gif); }',
                "foo { background: url($red), url($green); "
                    . "background: url(http://localhost/w/red.gif?34ac6), "
                    . "url(http://localhost/w/green.gif?13651)!ie; }",
            ],
            [
                'Two embedded files in one rule (inline @embed)',
                'foo { background: /* @embed */ url(red.gif), /* @embed */ url(green.gif); }',
                "foo { background: url($red), url($green); "
                    . "background: url(http://localhost/w/red.gif?34ac6), "
                    . "url(http://localhost/w/green.gif?13651)!ie; }",
            ],
            [
                'Two embedded files in one rule (inline @embed), one too large',
                'foo { background: /* @embed */ url(red.gif), /* @embed */ url(large.png); }',
                "foo { background: url($red), url(http://localhost/w/large.png?e3d1f); "
                    . "background: url(http://localhost/w/red.gif?34ac6), "
                    . "url(http://localhost/w/large.png?e3d1f)!ie; }",
            ],
            [
                'Practical example with some noise',
                'foo { /* @embed */ background: #f9f9f9 url(red.gif) 0 0 no-repeat; }',
                "foo { background: #f9f9f9 url($red) 0 0 no-repeat; "
                    . "background: #f9f9f9 url(http://localhost/w/red.gif?34ac6) 0 0 no-repeat!ie; }",
            ],
            [
                'Does not mess with other properties',
                'foo { color: red; background: url(red.gif); font-size: small; }',
                'foo { color: red; background: url(http://localhost/w/red.gif?34ac6); font-size: small; }',
            ],
            [
                'Spacing and miscellanea not changed (1)',
                'foo {   background:    url(red.gif);  }',
                'foo {   background:    url(http://localhost/w/red.gif?34ac6);  }',
            ],
            [
                'Spacing and miscellanea not changed (2)',
                'foo {background:url(red.gif)}',
                'foo {background:url(http://localhost/w/red.gif?34ac6)}',
            ],
            [
                'Spaces within url() parentheses are ignored',
                'foo { background: url( red.gif ); }',
                'foo { background: url(http://localhost/w/red.gif?34ac6); }',
            ],
            [
                '@import rule to local file (should we remap this?)',
                '@import url(/styles.css)',
                '@import url(https://expand.example/styles.css)',
            ],
            [
                '@import rule to local file (should we remap this?)',
                '@import url(/styles.css)',
                '@import url(https://expand.example/styles.css)',
            ],
            [
                '@import rule to URL',
                '@import url(//localhost/styles.css?query=val)',
                '@import url(//localhost/styles.css?query=val)',
            ],
            [
                'Background URL (double quotes)',
                'foo { background: url("//localhost/styles.css?quoted=double") }',
                'foo { background: url(//localhost/styles.css?quoted=double) }',
            ],
            [
                'Background URL (single quotes)',
                'foo { background: url(\'//localhost/styles.css?quoted=single\') }',
                'foo { background: url(//localhost/styles.css?quoted=single) }',
            ],
            [
                'Background URL (double quoted, containing parentheses; T60473)',
                'foo { background: url("//localhost/styles.css?query=(parens)") }',
                'foo { background: url("//localhost/styles.css?query=(parens)") }',
            ],
            [
                'Background URL (double quoted, containing single quotes; T60473)',
                'foo { background: url("//localhost/styles.css?quote=\'") }',
                'foo { background: url("//localhost/styles.css?quote=\'") }',
            ],
            [
                'Background URL (single quoted, containing double quotes; T60473)',
                'foo { background: url(\'//localhost/styles.css?quote="\') }',
                'foo { background: url("//localhost/styles.css?quote=\"") }',
            ],
            [
                'Background URL (double quoted with outer spacing)',
                'foo { background: url( "http://localhost/styles.css?quoted=double" ) }',
                'foo { background: url(http://localhost/styles.css?quoted=double) }',
            ],
            [
                'Simple case with comments before url',
                'foo { prop: /* some {funny;} comment */ url(bar.png); }',
                'foo { prop: /* some {funny;} comment */ url(http://localhost/w/bar.png); }',
            ],
            [
                'Simple case with comments after url',
                'foo { prop: url(red.gif)/* some {funny;} comment */ ; }',
                'foo { prop: url(http://localhost/w/red.gif?34ac6)/* some {funny;} comment */ ; }',
            ],
            [
                'Embedded file with comment before url',
                'foo { /* @embed */ background: /* some {funny;} comment */ url(red.gif); }',
                "foo { background: /* some {funny;} comment */ url($red); background: /* some {funny;} comment */ url(http://localhost/w/red.gif?34ac6)!ie; }",
            ],
            [
                'Embedded file with comments inside and outside the rule',
                'foo { /* @embed */ background: url(red.gif) /* some {foo;} comment */; /* some {bar;} comment */ }',
                "foo { background: url($red) /* some {foo;} comment */; background: url(http://localhost/w/red.gif?34ac6) /* some {foo;} comment */!ie; /* some {bar;} comment */ }",
            ],
            [
                'Embedded file with comment outside the rule',
                'foo { /* @embed */ background: url(red.gif); /* some {funny;} comment */ }',
                "foo { background: url($red); background: url(http://localhost/w/red.gif?34ac6)!ie; /* some {funny;} comment */ }",
            ],
            [
                'Rule with two urls, each with comments',
                '{ background: /*asd*/ url(something.png); background: /*jkl*/ url(something.png); }',
                '{ background: /*asd*/ url(http://localhost/w/something.png); background: /*jkl*/ url(http://localhost/w/something.png); }',
            ],
            [
                'Sanity check for offending line from jquery.ui.theme.css (T62077)',
                '.ui-state-default, .ui-widget-content .ui-state-default, .ui-widget-header .ui-state-default { border: 1px solid #d3d3d3/*{borderColorDefault}*/; background: #e6e6e6/*{bgColorDefault}*/ url(images/ui-bg_glass_75_e6e6e6_1x400.png)/*{bgImgUrlDefault}*/ 50%/*{bgDefaultXPos}*/ 50%/*{bgDefaultYPos}*/ repeat-x/*{bgDefaultRepeat}*/; font-weight: normal/*{fwDefault}*/; color: #555555/*{fcDefault}*/; }',
                '.ui-state-default, .ui-widget-content .ui-state-default, .ui-widget-header .ui-state-default { border: 1px solid #d3d3d3/*{borderColorDefault}*/; background: #e6e6e6/*{bgColorDefault}*/ url(http://localhost/w/images/ui-bg_glass_75_e6e6e6_1x400.png)/*{bgImgUrlDefault}*/ 50%/*{bgDefaultXPos}*/ 50%/*{bgDefaultYPos}*/ repeat-x/*{bgDefaultRepeat}*/; font-weight: normal/*{fwDefault}*/; color: #555555/*{fcDefault}*/; }',
            ],
        ];
        // phpcs:enable
    }
 
    public function testBuildUrlValue( $message, $input, $expectedOutput ) {
        $this->assertEquals(
            $expectedOutput,
            CSSMin::buildUrlValue( $input ),
            "CSSMin::buildUrlValue: $message"
        );
    }
 
    public static function provideBuildUrlValueCases() {
        return [
            [
                'Full URL',
                'scheme://user@domain:port/~user/fi%20le.png?query=yes&really=y+s',
                'url(scheme://user@domain:port/~user/fi%20le.png?query=yes&really=y+s)',
            ],
            [
                'data: URI',
                'data:image/png;base64,R0lGODlh/+==',
                'url(data:image/png;base64,R0lGODlh/+==)',
            ],
            [
                'URL with quotes',
                "https://en.wikipedia.org/wiki/Wendy's",
                "url(\"https://en.wikipedia.org/wiki/Wendy's\")",
            ],
            [
                'URL with parentheses',
                'https://en.wikipedia.org/wiki/Boston_(band)',
                'url("https://en.wikipedia.org/wiki/Boston_(band)")',
            ],
        ];
    }
 
    public function testMinifyWithCSSStringValues( $code, $expectedOutput ) {
        $this->testMinifyOutput( $code, $expectedOutput );
    }
 
    public static function provideStringCases() {
        return [
            // String values should be respected
            // - More than one space in a string value
            [ 'foo { content: "  "; }', 'foo{content:"  "}' ],
            // - Using a tab in a string value (turns into a space)
            [ "foo { content: '\t'; }", "foo{content:'\t'}" ],
            // - Using css-like syntax in string values
            [
                'foo::after { content: "{;}"; position: absolute; }',
                'foo::after{content:"{;}";position:absolute}'
            ],
        ];
    }
}