Deprecate @import and global builtins

CHANGELOG.md

@@ -1,3 +1,11 @@
+## 1.78.0
+
+* `@import` is now officially deprecated, as are global built-in functions that
+  are available within built-in modules. See [the Sass blog post] for more
+  details on the deprecation process.
+
+[the Sass blog]: https://sass-lang.com/blog/import-is-deprecated/
+
 ## 1.77.8
 
 * No user-visible changes.

lib/src/callable.dart

@@ -11,7 +11,8 @@ import 'utils.dart';
 import 'value.dart';
 
 export 'callable/async.dart';
-export 'callable/async_built_in.dart' show AsyncBuiltInCallable;
+export 'callable/async_built_in.dart'
+    show AsyncBuiltInCallable, warnForGlobalBuiltIn;
 export 'callable/built_in.dart' show BuiltInCallable;
 export 'callable/plain_css.dart';
 export 'callable/user_defined.dart';

lib/src/callable/async_built_in.dart

@@ -5,6 +5,8 @@
 import 'dart:async';
 
 import '../ast/sass.dart';
+import '../deprecation.dart';
+import '../evaluation_context.dart';
 import '../value.dart';
 import 'async.dart';
 
@@ -83,4 +85,23 @@ class AsyncBuiltInCallable implements AsyncCallable {
   (ArgumentDeclaration, Callback) callbackFor(
           int positional, Set<String> names) =>
       (_arguments, _callback);
+
+  /// Returns a copy of this callable that emits a deprecation warning.
+  AsyncBuiltInCallable withDeprecationWarning(String module,
+          [String? newName]) =>
+      AsyncBuiltInCallable.parsed(name, _arguments, (args) {
+        warnForGlobalBuiltIn(module, newName ?? name);
+        return _callback(args);
+      }, acceptsContent: acceptsContent);
+}
+
+/// Emits a deprecation warning for a global built-in function that is now
+/// available as function [name] in built-in module [module].
+void warnForGlobalBuiltIn(String module, String name) {
+  warnForDeprecation(
+      'Global built-in functions are deprecated and '
+      'will be removed in Dart Sass 3.0.0.\n'
+      'Use $module.$name instead.\n\n'
+      'More info and automated migrator: https://sass-lang.com/d/import',
+      Deprecation.globalBuiltin);
 }

lib/src/callable/built_in.dart

@@ -123,4 +123,20 @@ final class BuiltInCallable implements Callable, AsyncBuiltInCallable {
   /// Returns a copy of this callable with the given [name].
   BuiltInCallable withName(String name) =>
       BuiltInCallable._(name, _overloads, acceptsContent);
+
+  /// Returns a copy of this callable that emits a deprecation warning.
+  BuiltInCallable withDeprecationWarning(String module, [String? newName]) =>
+      BuiltInCallable._(
+          name,
+          [
+            for (var (declaration, function) in _overloads)
+              (
+                declaration,
+                (args) {
+                  warnForGlobalBuiltIn(module, newName ?? name);
+                  return function(args);
+                }
+              )
+          ],
+          acceptsContent);
 }

lib/src/deprecation.dart

@@ -15,7 +15,7 @@ enum Deprecation {
   // DO NOT EDIT. This section was generated from the language repo.
   // See tool/grind/generate_deprecations.dart for details.
   //
-  // Checksum: 309e4f1f008f08379b824ab6094e13df2e18e187
+  // Checksum: 89166027dc458357cbea646fd77fa44d9d7461cb
 
   /// Deprecation for passing a string directly to meta.call().
   callString('call-string',
@@ -96,7 +96,13 @@ enum Deprecation {
       description: 'Declarations after or between nested rules.'),
 
   /// Deprecation for @import rules.
-  import.future('import', description: '@import rules.'),
+  import('import', deprecatedIn: '1.78.0', description: '@import rules.'),
+
+  /// Deprecation for global built-in functions that are available in sass: modules.
+  globalBuiltin('global-builtin',
+      deprecatedIn: '1.78.0',
+      description:
+          'Global built-in functions that are available in sass: modules.'),
 
   // END AUTOGENERATED CODE
 

lib/src/functions/color.dart

@@ -23,7 +23,8 @@ final _microsoftFilterStart = RegExp(r'^[a-zA-Z]+\s*=');
 /// The global definitions of Sass color functions.
 final global = UnmodifiableListView([
   // ### RGB
-  _red, _green, _blue, _mix,
+  _red.withDeprecationWarning('color'), _green.withDeprecationWarning('color'),
+  _blue.withDeprecationWarning('color'), _mix.withDeprecationWarning('color'),
 
   BuiltInCallable.overloadedFunction("rgb", {
     r"$red, $green, $blue, $alpha": (arguments) => _rgb("rgb", arguments),
@@ -66,10 +67,13 @@ final global = UnmodifiableListView([
         red: 255 - color.red, green: 255 - color.green, blue: 255 - color.blue);
 
     return _mixColors(inverse, color, weight);
-  }),
+  }).withDeprecationWarning('color'),
 
   // ### HSL
-  _hue, _saturation, _lightness, _complement,
+  _hue.withDeprecationWarning('color'),
+  _saturation.withDeprecationWarning('color'),
+  _lightness.withDeprecationWarning('color'),
+  _complement.withDeprecationWarning('color'),
 
   BuiltInCallable.overloadedFunction("hsl", {
     r"$hue, $saturation, $lightness, $alpha": (arguments) =>
@@ -116,7 +120,7 @@ final global = UnmodifiableListView([
       // Use the native CSS `grayscale` filter function.
       return _functionString('grayscale', arguments);
     }
-
+    warnForGlobalBuiltIn('color', 'grayscale');
     var color = arguments[0].assertColor("color");
     return color.changeHsl(saturation: 0);
   }),
@@ -125,23 +129,23 @@ final global = UnmodifiableListView([
     var color = arguments[0].assertColor("color");
     var degrees = _angleValue(arguments[1], "degrees");
     return color.changeHsl(hue: color.hue + degrees);
-  }),
+  }).withDeprecationWarning('color', 'adjust'),
 
   _function("lighten", r"$color, $amount", (arguments) {
     var color = arguments[0].assertColor("color");
     var amount = arguments[1].assertNumber("amount");
     return color.changeHsl(
         lightness: (color.lightness + amount.valueInRange(0, 100, "amount"))
             .clamp(0, 100));
-  }),
+  }).withDeprecationWarning('color', 'adjust'),
 
   _function("darken", r"$color, $amount", (arguments) {
     var color = arguments[0].assertColor("color");
     var amount = arguments[1].assertNumber("amount");
     return color.changeHsl(
         lightness: (color.lightness - amount.valueInRange(0, 100, "amount"))
             .clamp(0, 100));
-  }),
+  }).withDeprecationWarning('color', 'adjust'),
 
   BuiltInCallable.overloadedFunction("saturate", {
     r"$amount": (arguments) {
@@ -153,6 +157,7 @@ final global = UnmodifiableListView([
       return SassString("saturate(${number.toCssString()})", quotes: false);
     },
     r"$color, $amount": (arguments) {
+      warnForGlobalBuiltIn('color', 'adjust');
       var color = arguments[0].assertColor("color");
       var amount = arguments[1].assertNumber("amount");
       return color.changeHsl(
@@ -167,13 +172,17 @@ final global = UnmodifiableListView([
     return color.changeHsl(
         saturation: (color.saturation - amount.valueInRange(0, 100, "amount"))
             .clamp(0, 100));
-  }),
+  }).withDeprecationWarning('color', 'adjust'),
 
   // ### Opacity
-  _function("opacify", r"$color, $amount", _opacify),
-  _function("fade-in", r"$color, $amount", _opacify),
-  _function("transparentize", r"$color, $amount", _transparentize),
-  _function("fade-out", r"$color, $amount", _transparentize),
+  _function("opacify", r"$color, $amount", _opacify)
+      .withDeprecationWarning('color', 'adjust'),
+  _function("fade-in", r"$color, $amount", _opacify)
+      .withDeprecationWarning('color', 'adjust'),
+  _function("transparentize", r"$color, $amount", _transparentize)
+      .withDeprecationWarning('color', 'adjust'),
+  _function("fade-out", r"$color, $amount", _transparentize)
+      .withDeprecationWarning('color', 'adjust'),
 
   BuiltInCallable.overloadedFunction("alpha", {
     r"$color": (arguments) {
@@ -184,6 +193,7 @@ final global = UnmodifiableListView([
         // Support the proprietary Microsoft alpha() function.
         return _functionString("alpha", arguments);
       }
+      warnForGlobalBuiltIn('color', 'alpha');
 
       var color = argument.assertColor("color");
       return SassNumber(color.alpha);
@@ -215,15 +225,16 @@ final global = UnmodifiableListView([
       return _functionString("opacity", arguments);
     }
 
+    warnForGlobalBuiltIn('color', 'opacity');
     var color = arguments[0].assertColor("color");
     return SassNumber(color.alpha);
   }),
 
   // ### Miscellaneous
   _ieHexStr,
-  _adjust.withName("adjust-color"),
-  _scale.withName("scale-color"),
-  _change.withName("change-color")
+  _adjust.withDeprecationWarning('color').withName("adjust-color"),
+  _scale.withDeprecationWarning('color').withName("scale-color"),
+  _change.withDeprecationWarning('color').withName("change-color")
 ]);
 
 /// The Sass color module.

lib/src/functions/list.dart

@@ -13,8 +13,15 @@ import '../value.dart';
 
 /// The global definitions of Sass list functions.
 final global = UnmodifiableListView([
-  _length, _nth, _setNth, _join, _append, _zip, _index, _isBracketed, //
-  _separator.withName("list-separator")
+  _length.withDeprecationWarning('list'),
+  _nth.withDeprecationWarning('list'),
+  _setNth.withDeprecationWarning('list'),
+  _join.withDeprecationWarning('list'),
+  _append.withDeprecationWarning('list'),
+  _zip.withDeprecationWarning('list'),
+  _index.withDeprecationWarning('list'),
+  _isBracketed.withDeprecationWarning('list'),
+  _separator.withDeprecationWarning('list').withName("list-separator")
 ]);
 
 /// The Sass list module.

lib/src/functions/map.dart

@@ -15,12 +15,12 @@ import '../value.dart';
 
 /// The global definitions of Sass map functions.
 final global = UnmodifiableListView([
-  _get.withName("map-get"),
-  _merge.withName("map-merge"),
-  _remove.withName("map-remove"),
-  _keys.withName("map-keys"),
-  _values.withName("map-values"),
-  _hasKey.withName("map-has-key")
+  _get.withDeprecationWarning('map').withName("map-get"),
+  _merge.withDeprecationWarning('map').withName("map-merge"),
+  _remove.withDeprecationWarning('map').withName("map-remove"),
+  _keys.withDeprecationWarning('map').withName("map-keys"),
+  _values.withDeprecationWarning('map').withName("map-values"),
+  _hasKey.withDeprecationWarning('map').withName("map-has-key")
 ]);
 
 /// The Sass map module.

lib/src/functions/math.dart

@@ -30,15 +30,23 @@ final global = UnmodifiableListView([
           "To emit a CSS abs() now: abs(#{$number})\n"
           "More info: https://sass-lang.com/d/abs-percent",
           Deprecation.absPercent);
+    } else {
+      warnForGlobalBuiltIn('math', 'abs');
     }
     return SassNumber.withUnits(number.value.abs(),
         numeratorUnits: number.numeratorUnits,
         denominatorUnits: number.denominatorUnits);
   }),
-
-  _ceil, _floor, _max, _min, _percentage, _randomFunction, _round, _unit, //
-  _compatible.withName("comparable"),
-  _isUnitless.withName("unitless"),
+  _ceil.withDeprecationWarning('math'),
+  _floor.withDeprecationWarning('math'),
+  _max.withDeprecationWarning('math'),
+  _min.withDeprecationWarning('math'),
+  _percentage.withDeprecationWarning('math'),
+  _randomFunction.withDeprecationWarning('math'),
+  _round.withDeprecationWarning('math'),
+  _unit.withDeprecationWarning('math'),
+  _compatible.withDeprecationWarning('math').withName("comparable"),
+  _isUnitless.withDeprecationWarning('math').withName("unitless"),
 ]);
 
 /// The Sass math module.

lib/src/functions/meta.dart

@@ -20,19 +20,18 @@ final _features = {
   "custom-property"
 };
 
-/// The global definitions of Sass introspection functions.
-final global = UnmodifiableListView([
-  // This is only a partial list of meta functions. The rest are defined in the
-  // evaluator, because they need access to context that's only available at
-  // runtime.
+/// Sass introspection functions that exist as both global functions and in the
+/// `sass:meta` module that do not require access to context that's only
+/// available at runtime.
+///
+/// Additional functions are defined in the evaluator.
+final _shared = UnmodifiableListView([
   _function("feature-exists", r"$feature", (arguments) {
     var feature = arguments[0].assertString("feature");
     return SassBoolean(_features.contains(feature.text));
   }),
-
   _function("inspect", r"$value",
       (arguments) => SassString(arguments.first.toString(), quotes: false)),
-
   _function(
       "type-of",
       r"$value",
@@ -52,7 +51,6 @@ final global = UnmodifiableListView([
             _ => throw "[BUG] Unknown value type ${arguments[0]}"
           },
           quotes: false)),
-
   _function("keywords", r"$args", (arguments) {
     if (arguments[0] case SassArgumentList(:var keywords)) {
       return SassMap({
@@ -65,9 +63,14 @@ final global = UnmodifiableListView([
   })
 ]);
 
-/// The definitions of Sass introspection functions that are only available from
-/// the `sass:meta` module, not as global functions.
-final local = UnmodifiableListView([
+/// The global definitions of Sass introspection functions.
+final global = UnmodifiableListView(
+    [for (var function in _shared) function.withDeprecationWarning('meta')]);
+
+/// The versions of Sass introspection functions defined in the `sass:meta`
+/// module.
+final moduleFunctions = UnmodifiableListView([
+  ..._shared,
   _function("calc-name", r"$calc", (arguments) {
     var calculation = arguments[0].assertCalculation("calc");
     return SassString(calculation.name);

lib/src/functions/selector.dart

@@ -16,14 +16,14 @@ import '../value.dart';
 
 /// The global definitions of Sass selector functions.
 final global = UnmodifiableListView([
-  _isSuperselector,
-  _simpleSelectors,
-  _parse.withName("selector-parse"),
-  _nest.withName("selector-nest"),
-  _append.withName("selector-append"),
-  _extend.withName("selector-extend"),
-  _replace.withName("selector-replace"),
-  _unify.withName("selector-unify")
+  _isSuperselector.withDeprecationWarning('selector'),
+  _simpleSelectors.withDeprecationWarning('selector'),
+  _parse.withDeprecationWarning('selector').withName("selector-parse"),
+  _nest.withDeprecationWarning('selector').withName("selector-nest"),
+  _append.withDeprecationWarning('selector').withName("selector-append"),
+  _extend.withDeprecationWarning('selector').withName("selector-extend"),
+  _replace.withDeprecationWarning('selector').withName("selector-replace"),
+  _unify.withDeprecationWarning('selector').withName("selector-unify")
 ]);
 
 /// The Sass selector module.

lib/src/functions/string.dart

@@ -22,11 +22,15 @@ var _previousUniqueId = _random.nextInt(math.pow(36, 6) as int);
 
 /// The global definitions of Sass string functions.
 final global = UnmodifiableListView([
-  _unquote, _quote, _toUpperCase, _toLowerCase, _uniqueId, //
-  _length.withName("str-length"),
-  _insert.withName("str-insert"),
-  _index.withName("str-index"),
-  _slice.withName("str-slice")
+  _unquote.withDeprecationWarning('string'),
+  _quote.withDeprecationWarning('string'),
+  _toUpperCase.withDeprecationWarning('string'),
+  _toLowerCase.withDeprecationWarning('string'),
+  _uniqueId.withDeprecationWarning('string'),
+  _length.withDeprecationWarning('string').withName("str-length"),
+  _insert.withDeprecationWarning('string').withName("str-insert"),
+  _index.withDeprecationWarning('string').withName("str-index"),
+  _slice.withDeprecationWarning('string').withName("str-slice")
 ]);
 
 /// The Sass string module.

lib/src/parse/stylesheet.dart

@@ -1052,9 +1052,10 @@ abstract class StylesheetParser extends Parser {
       if (argument is DynamicImport) {
         logger.warnForDeprecation(
             Deprecation.import,
-            'Sass @import rules will be deprecated in the future.\n'
-            'Remove the --future-deprecation=import flag to silence this '
-            'warning for now.',
+            'Sass @import rules are deprecated '
+            'and will be removed in Dart Sass 3.0.0.\n\n'
+            'More info and automated migrator: '
+            'https://sass-lang.com/d/import',
             span: argument.span);
       }
       if ((_inControlDirective || _inMixin) && argument is DynamicImport) {