Merge pull request #204 from sass/unquoted-import

Support unquoted imports in the indented syntax

Author: nex3

CHANGELOG.md

@@ -1,5 +1,7 @@
 ## 1.0.0-beta.4
 
+* Support unquoted imports in the indented syntax.
+
 * Fix a crash when `:not(...)` extends a selector that appears in
   `:not(:not(...))`.
 

lib/src/parse/parser.dart

@@ -3,6 +3,7 @@
 // https://opensource.org/licenses/MIT.
 
 import 'package:charcode/charcode.dart';
+import 'package:meta/meta.dart';
 import 'package:source_span/source_span.dart';
 import 'package:string_scanner/string_scanner.dart';
 
@@ -24,20 +25,23 @@ abstract class Parser {
   // ## Tokens
 
   /// Consumes whitespace, including any comments.
+  @protected
   void whitespace() {
     do {
       whitespaceWithoutComments();
     } while (scanComment());
   }
 
   /// Like [whitespace], but returns whether any was consumed.
+  @protected
   bool scanWhitespace() {
     var start = scanner.position;
     whitespace();
     return scanner.position != start;
   }
 
   /// Consumes whitespace, but not comments.
+  @protected
   void whitespaceWithoutComments() {
     while (!scanner.isDone && isWhitespace(scanner.peekChar())) {
       scanner.readChar();
@@ -47,6 +51,7 @@ abstract class Parser {
   /// Consumes and ignores a comment if possible.
   ///
   /// Returns whether the comment was consumed.
+  @protected
   bool scanComment() {
     if (scanner.peekChar() != $slash) return false;
 
@@ -63,6 +68,7 @@ abstract class Parser {
   }
 
   /// Consumes and ignores a silent (Sass-style) comment.
+  @protected
   void silentComment() {
     scanner.expect("//");
     while (!scanner.isDone && !isNewline(scanner.peekChar())) {
@@ -71,6 +77,7 @@ abstract class Parser {
   }
 
   /// Consumes and ignores a loud (CSS-style) comment.
+  @protected
   void loudComment() {
     scanner.expect("/*");
     while (true) {
@@ -89,6 +96,7 @@ abstract class Parser {
   /// If [unit] is `true`, this doesn't parse a `-` followed by a digit. This
   /// ensures that `1px-2px` parses as subtraction rather than the unit
   /// `px-2px`.
+  @protected
   String identifier({bool unit: false}) {
     // NOTE: this logic is largely duplicated in ScssParser.identifier.
     // Most changes here should be mirrored there.
@@ -114,6 +122,7 @@ abstract class Parser {
   }
 
   /// Consumes a chunk of a plain CSS identifier after the name start.
+  @protected
   String identifierBody() {
     var text = new StringBuffer();
     _identifierBody(text);
@@ -146,6 +155,7 @@ abstract class Parser {
   ///
   /// This returns the parsed contents of the string—that is, it doesn't include
   /// quotes and its escapes are resolved.
+  @protected
   String string() {
     // NOTE: this logic is largely duplicated in ScssParser._interpolatedString.
     // Most changes here should be mirrored there.
@@ -181,6 +191,7 @@ abstract class Parser {
 
   /// Consumes tokens until it reaches a top-level `":"`, `"!"`, `")"`, `"]"`,
   /// or `"}"` and returns their contents as a string.
+  @protected
   String declarationValue() {
     // NOTE: this logic is largely duplicated in
     // StylesheetParser._interpolatedDeclarationValue. Most changes here should
@@ -281,6 +292,7 @@ abstract class Parser {
   }
 
   /// Consumes a `url()` token if possible, and returns `null` otherwise.
+  @protected
   String tryUrl() {
     // NOTE: this logic is largely duplicated in ScssParser._urlContents and
     // ScssParser._tryUrlContents. Most changes here should be mirrored there.
@@ -327,6 +339,7 @@ abstract class Parser {
 
   /// Consumes a Sass variable name, and returns its name without the dollar
   /// sign.
+  @protected
   String variableName() {
     scanner.expectChar($dollar);
     return identifier();
@@ -335,6 +348,7 @@ abstract class Parser {
   // ## Characters
 
   /// Consumes an escape sequence and returns the text that defines it.
+  @protected
   String escape() {
     // See https://drafts.csswg.org/css-syntax-3/#consume-escaped-code-point.
 
@@ -365,6 +379,7 @@ abstract class Parser {
   }
 
   /// Consumes an escape sequence and returns the character it represents.
+  @protected
   int escapeCharacter() {
     // See https://drafts.csswg.org/css-syntax-3/#consume-escaped-code-point.
 
@@ -399,6 +414,7 @@ abstract class Parser {
   // Consumes the next character if it matches [condition].
   //
   // Returns whether or not the character was consumed.
+  @protected
   bool scanCharIf(bool condition(int character)) {
     var next = scanner.peekChar();
     if (!condition(next)) return false;
@@ -408,6 +424,7 @@ abstract class Parser {
 
   /// Consumes the next character if it's equal to [letter], ignoring ASCII
   /// case.
+  @protected
   bool scanCharIgnoreCase(int letter) {
     if (!equalsLetterIgnoreCase(letter, scanner.peekChar())) return false;
     scanner.readChar();
@@ -416,6 +433,7 @@ abstract class Parser {
 
   /// Consumes the next character and asserts that it's equal to [letter],
   /// ignoring ASCII case.
+  @protected
   void expectCharIgnoreCase(int letter) {
     var actual = scanner.readChar();
     if (equalsLetterIgnoreCase(letter, actual)) return;
@@ -431,6 +449,7 @@ abstract class Parser {
   /// This follows [the CSS algorithm][].
   ///
   /// [the CSS algorithm]: https://drafts.csswg.org/css-syntax-3/#starts-with-a-number
+  @protected
   bool lookingAtNumber() {
     var first = scanner.peekChar();
     if (first == null) return false;
@@ -460,6 +479,7 @@ abstract class Parser {
   /// start escapes.
   ///
   /// [the CSS algorithm]: https://drafts.csswg.org/css-syntax-3/#would-start-an-identifier
+  @protected
   bool lookingAtIdentifier([int forward]) {
     // See also [ScssParser._lookingAtInterpolatedIdentifier].
 
@@ -480,6 +500,7 @@ abstract class Parser {
 
   /// Returns whether the scanner is immediately before a sequence of characters
   /// that could be part of a plain CSS identifier body.
+  @protected
   bool lookingAtIdentifierBody() {
     var next = scanner.peekChar();
     return next != null && (isName(next) || next == $backslash);
@@ -488,6 +509,7 @@ abstract class Parser {
   /// Consumes an identifier if its name exactly matches [text].
   ///
   /// If [ignoreCase] is `true`, does a case-insensitive match.
+  @protected
   bool scanIdentifier(String text, {bool ignoreCase: false}) {
     if (!lookingAtIdentifier()) return false;
 
@@ -507,6 +529,7 @@ abstract class Parser {
   /// Consumes an identifier and asserts that its name exactly matches [text].
   ///
   /// If [ignoreCase] is `true`, does a case-insensitive match.
+  @protected
   void expectIdentifier(String text, {String name, bool ignoreCase: false}) {
     name ??= '"$text"';
 
@@ -522,6 +545,7 @@ abstract class Parser {
   }
 
   /// Runs [consumer] and returns the source text that it consumes.
+  @protected
   String rawText(void consumer()) {
     var start = scanner.position;
     consumer();
@@ -532,6 +556,7 @@ abstract class Parser {
   ///
   /// If [message] is passed, prints that as well. This is intended for use when
   /// debugging parser failures.
+  @protected
   void debug([message]) {
     if (message == null) {
       print(scanner.emptySpan.highlight(color: true));
@@ -542,6 +567,7 @@ abstract class Parser {
 
   /// Runs [callback] and wraps any [SourceSpanFormatException] it throws in a
   /// [SassFormatException].
+  @protected
   T wrapSpanFormatException<T>(T callback()) {
     try {
       return callback();

lib/src/parse/sass.dart

@@ -59,6 +59,40 @@ class SassParser extends StylesheetParser {
   bool lookingAtChildren() =>
       atEndOfStatement() && _peekIndentation() > currentIndentation;
 
+  Import importArgument() {
+    switch (scanner.peekChar()) {
+      case $u:
+      case $U:
+        var start = scanner.state;
+        if (scanIdentifier("url", ignoreCase: true)) {
+          if (scanner.scanChar($lparen)) {
+            scanner.state = start;
+            return super.importArgument();
+          } else {
+            scanner.state = start;
+          }
+        }
+        break;
+
+      case $single_quote:
+      case $double_quote:
+        return super.importArgument();
+    }
+
+    var start = scanner.state;
+    var next = scanner.peekChar();
+    while (next != null &&
+        next != $comma &&
+        next != $semicolon &&
+        !isNewline(next)) {
+      scanner.readChar();
+      next = scanner.peekChar();
+    }
+
+    return new DynamicImport(parseImportUrl(scanner.substring(start.position)),
+        scanner.spanFrom(start));
+  }
+
   bool scanElse(int ifIndentation) {
     if (_peekIndentation() != ifIndentation) return false;
     var start = scanner.state;

lib/src/parse/stylesheet.dart

@@ -5,6 +5,7 @@
 import 'dart:math' as math;
 
 import 'package:charcode/charcode.dart';
+import 'package:meta/meta.dart';
 import 'package:path/path.dart' as p;
 import 'package:string_scanner/string_scanner.dart';
 import 'package:tuple/tuple.dart';
@@ -57,8 +58,7 @@ abstract class StylesheetParser extends Parser {
   var _inParentheses = false;
 
   /// Whether warnings should be emitted using terminal colors.
-  ///
-  /// This is protected and shouldn't be accessed except by subclasses.
+  @protected
   final bool color;
 
   StylesheetParser(String contents, {url, this.color: false})
@@ -114,6 +114,7 @@ abstract class StylesheetParser extends Parser {
   }
 
   /// Consumes a variable declaration.
+  @protected
   VariableDeclaration variableDeclaration() {
     var start = scanner.state;
     var name = variableName();
@@ -697,7 +698,12 @@ abstract class StylesheetParser extends Parser {
     var imports = <Import>[];
     do {
       whitespace();
-      imports.add(_importArgument(start));
+      var argument = importArgument();
+      if ((_inControlDirective || _inMixin) && argument is DynamicImport) {
+        _disallowedAtRule(start);
+      }
+
+      imports.add(argument);
       whitespace();
     } while (scanner.scanChar($comma));
     expectStatementSeparator("@import rule");
@@ -708,7 +714,8 @@ abstract class StylesheetParser extends Parser {
   /// Consumes an argument to an `@import` rule.
   ///
   /// [ruleStart] should point before the `@`.
-  Import _importArgument(LineScannerState ruleStart) {
+  @protected
+  Import importArgument() {
     var start = scanner.state;
     var next = scanner.peekChar();
     if (next == $u || next == $U) {
@@ -728,20 +735,18 @@ abstract class StylesheetParser extends Parser {
       return new StaticImport(
           new Interpolation([urlSpan.text], urlSpan), scanner.spanFrom(start),
           supports: queries?.item1, media: queries?.item2);
-    } else if (_inControlDirective || _inMixin) {
-      _disallowedAtRule(ruleStart);
-      return null;
     } else {
       try {
-        return new DynamicImport(_parseImportUrl(url), urlSpan);
+        return new DynamicImport(parseImportUrl(url), urlSpan);
       } on FormatException catch (error) {
         throw new SassFormatException("Invalid URL: ${error.message}", urlSpan);
       }
     }
   }
 
   /// Parses [url] as an import URL.
-  Uri _parseImportUrl(String url) {
+  @protected
+  Uri parseImportUrl(String url) {
     // Backwards-compatibility for implementations that allow absolute Windows
     // paths in imports.
     if (p.windows.isAbsolute(url)) return p.windows.toUri(url);
@@ -2713,12 +2718,14 @@ abstract class StylesheetParser extends Parser {
   // ## Abstract Methods
 
   /// Whether this is parsing the indented syntax.
+  @protected
   bool get indented;
 
   /// The indentation level at the current scanner position.
   ///
   /// This value isn't used directly by [StylesheetParser]; it's just passed to
   /// [scanElse].
+  @protected
   int get currentIndentation;
 
   /// Asserts that the scanner is positioned before a statement separator, or at
@@ -2727,13 +2734,16 @@ abstract class StylesheetParser extends Parser {
   /// If the [name] of the parent rule is passed, it's used for error reporting.
   ///
   /// This consumes whitespace, but nothing else, including comments.
+  @protected
   void expectStatementSeparator([String name]);
 
   /// Whether the scanner is positioned at the end of a statement.
+  @protected
   bool atEndOfStatement();
 
   /// Whether the scanner is positioned before a block of children that can be
   /// parsed with [children].
+  @protected
   bool lookingAtChildren();
 
   /// Tries to scan an `@else` rule after an `@if` block, and returns whether
@@ -2742,14 +2752,17 @@ abstract class StylesheetParser extends Parser {
   /// This should just scan the rule name, not anything afterwards.
   /// [ifIndentation] is the result of [currentIndentation] from before the
   /// corresponding `@if` was parsed.
+  @protected
   bool scanElse(int ifIndentation);
 
   /// Consumes a block of child statements.
+  @protected
   List<Statement> children(Statement child());
 
   /// Consumes top-level statements.
   ///
   /// The [statement] callback may return `null`, indicating that a statement
   /// was consumed that shouldn't be added to the AST.
+  @protected
   List<Statement> statements(Statement statement());
 }