pkg/analysis_server/lib/src/computer/computer_color.dart - sdk.git - Git at Google

 // Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.

 import 'package:analysis_server/src/utilities/extensions/flutter.dart';
 import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/constant/value.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/src/dart/ast/ast.dart';
 import 'package:analyzer/src/dart/constant/value.dart' show GenericState;
 import 'package:analyzer/src/lint/linter.dart';
 import 'package:collection/collection.dart';
 import 'package:path/path.dart' as path;

 /// Computer for dart:ui/Flutter Color references.
 class ColorComputer {
   final ResolvedUnitResult resolvedUnit;
   final List<ColorReference> _colors = [];

   ColorComputer(this.resolvedUnit, path.Context pathContext);

   /// Returns information about the color references in [resolvedUnit].
   ///
   /// This method should only be called once for any instance of this class.
   List<ColorReference> compute() {
     var visitor = _ColorBuilder(this);
     resolvedUnit.unit.accept(visitor);
     assert(
       _colors.length == _colors.map((color) => color.offset).toSet().length,
       'Every color reference should have a unique offset',
     );
     return _colors;
   }

   /// Tries to add a color for the [expression].
   ///
   /// If [target] is supplied, will be used instead of [expression] allowing
   /// a value to be read from the member [memberName] or from a swatch value
   /// with index [index].
   bool tryAddColor(
     Expression expression, {
     Expression? target,
     String? memberName,
     int? index,
   }) {
     if (!expression.staticType.isColor) return false;

     target ??= expression;

     // Try to evaluate the constant target.
     var colorConstResult = target.computeConstantValue();
     var colorConst = colorConstResult.value;
     if (colorConstResult.errors.isNotEmpty || colorConst == null) return false;

     // If we want a specific member or swatch index, read that.
     if (memberName != null) {
       colorConst = _getMember(colorConst, memberName);
     } else if (index != null) {
       colorConst = _getSwatchValue(colorConst, index);
     }

     return _tryRecordColor(expression, colorConst);
   }

   /// Tries to add a color for the instance creation [expression].
   ///
   /// This handles constructor calls that cannot be evaluated (for example
   /// because they are not const) but are simple well-known dart:ui/Flutter
   /// color constructors that we can manually parse.
   bool tryAddKnownColorConstructor(InstanceCreationExpression expression) {
     if (!expression.staticType.isColor) return false;

     var constructor = expression.constructorName;
     var staticElement = constructor.staticElement;
     var classElement = staticElement?.enclosingElement3;
     var className = classElement?.name;
     var constructorName = constructor.name?.name;
     var constructorArgs = expression.argumentList.arguments
         .map((e) => e is Literal ? e : null)
         .toList();

     int? colorValue;
     if (_isDartUi(classElement) && className == 'Color') {
       colorValue = _getDartUiColorValue(constructorName, constructorArgs);
     } else if (_isFlutterPainting(classElement) && className == 'ColorSwatch') {
       colorValue =
           _getFlutterSwatchColorValue(constructorName, constructorArgs);
     } else if (_isFlutterMaterial(classElement) &&
         className == 'MaterialAccentColor') {
       colorValue =
           _getFlutterMaterialAccentColorValue(constructorName, constructorArgs);
     }

     return _tryRecordColorValue(expression, colorValue);
   }

   /// Converts ARGB values into a single int value as 0xAARRGGBB as used by
   /// the dart:ui Color class.
   int _colorValueForComponents(int alpha, int red, int green, int blue) {
     return (alpha << 24) | (red << 16) | (green << 8) | (blue << 0);
   }

   /// Extracts the color value from dart:ui Color constructor args.
   int? _getDartUiColorValue(String? name, List<Literal?> args) {
     if (name == null && args.length == 1) {
       var arg0 = args[0];
       return arg0 is IntegerLiteral ? arg0.value : null;
     } else if (name == 'fromARGB' && args.length == 4) {
       var arg0 = args[0];
       var arg1 = args[1];
       var arg2 = args[2];
       var arg3 = args[3];

       var alpha = arg0 is IntegerLiteral ? arg0.value : null;
       var red = arg1 is IntegerLiteral ? arg1.value : null;
       var green = arg2 is IntegerLiteral ? arg2.value : null;
       var blue = arg3 is IntegerLiteral ? arg3.value : null;

       return alpha != null && red != null && green != null && blue != null
           ? _colorValueForComponents(alpha, red, green, blue)
           : null;
     } else if (name == 'fromRGBO' && args.length == 4) {
       var arg0 = args[0];
       var arg1 = args[1];
       var arg2 = args[2];
       var arg3 = args[3];

       var red = arg0 is IntegerLiteral ? arg0.value : null;
       var green = arg1 is IntegerLiteral ? arg1.value : null;
       var blue = arg2 is IntegerLiteral ? arg2.value : null;
       var opacity = arg3 is IntegerLiteral
           ? arg3.value
           : arg3 is DoubleLiteral
               ? arg3.value
               : null;
       var alpha = opacity != null ? (opacity * 255).toInt() : null;

       return alpha != null && red != null && green != null && blue != null
           ? _colorValueForComponents(alpha, red, green, blue)
           : null;
     } else {
       return null;
     }
   }

   /// Extracts the color value from Flutter MaterialAccentColor constructor args.
   int? _getFlutterMaterialAccentColorValue(String? name, List<Literal?> args) =>
       // MaterialAccentColor is a subclass of SwatchColor and has the same
       // constructor.
       _getFlutterSwatchColorValue(name, args);

   /// Extracts the color value from Flutter ColorSwatch constructor args.
   int? _getFlutterSwatchColorValue(String? name, List<Literal?> args) {
     if (name == null && args.isNotEmpty) {
       var arg0 = args[0];
       return arg0 is IntegerLiteral ? arg0.value : null;
     } else {
       return null;
     }
   }

   /// Extracts a named member from a color.
   ///
   /// Well-known getters like `shade500` will be mapped onto the swatch value
   /// with a matching index.
   DartObject? _getMember(DartObject target, String memberName) {
     var colorValue = target.getFieldFromHierarchy(memberName);
     if (colorValue != null) {
       return colorValue;
     }

     // If we didn't get a value but it's a getter we know how to read from a
     // swatch, try that.
     if (memberName.startsWith('shade')) {
       var shadeNumber = int.tryParse(memberName.substring(5));
       if (shadeNumber != null) {
         return _getSwatchValue(target, shadeNumber);
       }
     }

     return null;
   }

   /// Extracts a specific shade index from a Flutter SwatchColor.
   DartObject? _getSwatchValue(DartObject target, int swatchValue) {
     var swatch = target.getFieldFromHierarchy('_swatch')?.toMapValue();
     if (swatch == null) return null;

     var key = swatch.keys.firstWhereOrNull(
       (key) => key?.toIntValue() == swatchValue,
     );
     if (key == null) return null;

     return swatch[key];
   }

   /// Checks whether this elements library is dart:ui.
   bool _isDartUi(Element? element) => element?.library?.name == 'dart.ui';

   /// Checks whether this elements library is Flutter Material colors.
   bool _isFlutterMaterial(Element? element) =>
       element?.library?.identifier ==
       'package:flutter/src/material/colors.dart';

   /// Checks whether this elements library is Flutter Painting colors.
   bool _isFlutterPainting(Element? element) =>
       element?.library?.identifier ==
       'package:flutter/src/painting/colors.dart';

   /// Tries to record a color value from [colorConst] for [expression].
   ///
   /// Returns whether a valid color was found and recorded.
   bool _tryRecordColor(Expression expression, DartObject? colorConst) =>
       _tryRecordColorValue(expression, _colorValueForColorConst(colorConst));

   /// Tries to record the [colorValue] for [expression].
   ///
   /// Returns whether a valid color was found and recorded.
   bool _tryRecordColorValue(Expression expression, int? colorValue) {
     if (colorValue == null) return false;

     // Build color information from the Color value.
     var color = _colorInformationForColorValue(colorValue);

     // Record the color against the original entire expression.
     _colors.add(ColorReference(expression.offset, expression.length, color));
     return true;
   }

   static ColorInformation? getColorForValue(DartObject object) {
     if (object.type.isColor) {
       var colorValue = _colorValueForColorConst(object);
       if (colorValue != null) {
         return _colorInformationForColorValue(colorValue);
       }
     }
     return null;
   }

   /// Creates a [ColorInformation] by extracting the argb values from
   /// [value] encoded as 0xAARRGGBB as in the dart:ui Color class.
   static ColorInformation _colorInformationForColorValue(int value) {
     // Extract color information according to dart:ui Color values.
     var alpha = (0xff000000 & value) >> 24;
     var red = (0x00ff0000 & value) >> 16;
     var blue = (0x000000ff & value) >> 0;
     var green = (0x0000ff00 & value) >> 8;

     return ColorInformation(alpha, red, green, blue);
   }

   /// Extracts the integer color value from the dart:ui Color constant [color].
   static int? _colorValueForColorConst(DartObject? color) {
     if (color == null || color.isNull) return null;

     // If the object has a "color" field, walk down to that, because some colors
     // like CupertinoColors have a "value=0" with an overridden getter that
     // would always result in a value representing black.
     color = color.getFieldFromHierarchy('color') ?? color;

     return color.getFieldFromHierarchy('value')?.toIntValue();
   }
 }

 /// Information about a color that is present in a document.
 class ColorInformation {
   final int alpha;
   final int red;
   final int green;
   final int blue;

   ColorInformation(this.alpha, this.red, this.green, this.blue);
 }

 /// Information about a specific known location of a [ColorInformation]
 /// reference in a document.
 class ColorReference {
   final int offset;
   final int length;
   final ColorInformation color;

   ColorReference(this.offset, this.length, this.color);
 }

 class _ColorBuilder extends RecursiveAstVisitor<void> {
   final ColorComputer computer;

   _ColorBuilder(this.computer);

   @override
   void visitIndexExpression(IndexExpression node) {
     // Colors.redAccent[500].
     var index = node.index;
     var indexValue = index is IntegerLiteral ? index.value : null;
     if (indexValue != null) {
       if (computer.tryAddColor(
         node,
         target: node.realTarget,
         index: indexValue,
       )) {
         return;
       }
     }
     super.visitIndexExpression(node);
   }

   @override
   void visitInstanceCreationExpression(InstanceCreationExpression node) {
     // Usually we return after finding a color, but constructors can
     // have nested colors in their arguments so we walk all the way down.
     if (!computer.tryAddColor(node)) {
       // If we couldn't evaluate the constant, try the well-known color
       // constructors for dart:ui/Flutter.
       computer.tryAddKnownColorConstructor(node);
     }

     super.visitInstanceCreationExpression(node);
   }

   @override
   void visitPrefixedIdentifier(PrefixedIdentifier node) {
     // Try the whole node as a constant (eg. `MyThemeClass.staticField`).
     if (computer.tryAddColor(node)) {
       return;
     }

     // Try a field of a static, (eg. `const MyThemeClass().instanceField`).
     if (computer.tryAddColor(
       node,
       target: node.prefix,
       memberName: node.identifier.name,
     )) {
       return;
     }

     super.visitPrefixedIdentifier(node);
   }

   @override
   void visitPropertyAccess(PropertyAccess node) {
     // Handle things like CupterinoColors.activeBlue.darkColor where we can't
     // evaluate the whole expression, but can evaluate CupterinoColors.activeBlue
     // and read the darkColor.
     if (computer.tryAddColor(
       node,
       target: node.realTarget,
       memberName: node.propertyName.name,
     )) {
       return;
     }

     super.visitPropertyAccess(node);
   }

   @override
   void visitSimpleIdentifier(SimpleIdentifier node) {
     computer.tryAddColor(node);

     super.visitSimpleIdentifier(node);
   }
 }

 extension _DartObjectExtensions on DartObject {
   /// Reads the value of the field [field] from this object.
   ///
   /// If the field is not found, recurses up the super classes.
   DartObject? getFieldFromHierarchy(String fieldName) =>
       getField(fieldName) ??
       getField(GenericState.SUPERCLASS_FIELD)?.getFieldFromHierarchy(fieldName);
 }
	// Copyright (c) 2021, the Dart project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.

	import 'package:analysis_server/src/utilities/extensions/flutter.dart';
	import 'package:analyzer/dart/analysis/results.dart';
	import 'package:analyzer/dart/ast/ast.dart';
	import 'package:analyzer/dart/ast/visitor.dart';
	import 'package:analyzer/dart/constant/value.dart';
	import 'package:analyzer/dart/element/element.dart';
	import 'package:analyzer/src/dart/ast/ast.dart';
	import 'package:analyzer/src/dart/constant/value.dart' show GenericState;
	import 'package:analyzer/src/lint/linter.dart';
	import 'package:collection/collection.dart';
	import 'package:path/path.dart' as path;

	/// Computer for dart:ui/Flutter Color references.
	class ColorComputer {
	final ResolvedUnitResult resolvedUnit;
	final List<ColorReference> _colors = [];

	ColorComputer(this.resolvedUnit, path.Context pathContext);

	/// Returns information about the color references in [resolvedUnit].
	///
	/// This method should only be called once for any instance of this class.
	List<ColorReference> compute() {
	var visitor = _ColorBuilder(this);
	resolvedUnit.unit.accept(visitor);
	assert(
	_colors.length == _colors.map((color) => color.offset).toSet().length,
	'Every color reference should have a unique offset',
	);
	return _colors;
	}

	/// Tries to add a color for the [expression].
	///
	/// If [target] is supplied, will be used instead of [expression] allowing
	/// a value to be read from the member [memberName] or from a swatch value
	/// with index [index].
	bool tryAddColor(
	Expression expression, {
	Expression? target,
	String? memberName,
	int? index,
	}) {
	if (!expression.staticType.isColor) return false;

	target ??= expression;

	// Try to evaluate the constant target.
	var colorConstResult = target.computeConstantValue();
	var colorConst = colorConstResult.value;
	if (colorConstResult.errors.isNotEmpty \|\| colorConst == null) return false;

	// If we want a specific member or swatch index, read that.
	if (memberName != null) {
	colorConst = _getMember(colorConst, memberName);
	} else if (index != null) {
	colorConst = _getSwatchValue(colorConst, index);
	}

	return _tryRecordColor(expression, colorConst);
	}

	/// Tries to add a color for the instance creation [expression].
	///
	/// This handles constructor calls that cannot be evaluated (for example
	/// because they are not const) but are simple well-known dart:ui/Flutter
	/// color constructors that we can manually parse.
	bool tryAddKnownColorConstructor(InstanceCreationExpression expression) {
	if (!expression.staticType.isColor) return false;

	var constructor = expression.constructorName;
	var staticElement = constructor.staticElement;
	var classElement = staticElement?.enclosingElement3;
	var className = classElement?.name;
	var constructorName = constructor.name?.name;
	var constructorArgs = expression.argumentList.arguments
	.map((e) => e is Literal ? e : null)
	.toList();

	int? colorValue;
	if (_isDartUi(classElement) && className == 'Color') {
	colorValue = _getDartUiColorValue(constructorName, constructorArgs);
	} else if (_isFlutterPainting(classElement) && className == 'ColorSwatch') {
	colorValue =
	_getFlutterSwatchColorValue(constructorName, constructorArgs);
	} else if (_isFlutterMaterial(classElement) &&
	className == 'MaterialAccentColor') {
	colorValue =
	_getFlutterMaterialAccentColorValue(constructorName, constructorArgs);
	}

	return _tryRecordColorValue(expression, colorValue);
	}

	/// Converts ARGB values into a single int value as 0xAARRGGBB as used by
	/// the dart:ui Color class.
	int _colorValueForComponents(int alpha, int red, int green, int blue) {
	return (alpha << 24) \| (red << 16) \| (green << 8) \| (blue << 0);
	}

	/// Extracts the color value from dart:ui Color constructor args.
	int? _getDartUiColorValue(String? name, List<Literal?> args) {
	if (name == null && args.length == 1) {
	var arg0 = args[0];
	return arg0 is IntegerLiteral ? arg0.value : null;
	} else if (name == 'fromARGB' && args.length == 4) {
	var arg0 = args[0];
	var arg1 = args[1];
	var arg2 = args[2];
	var arg3 = args[3];

	var alpha = arg0 is IntegerLiteral ? arg0.value : null;
	var red = arg1 is IntegerLiteral ? arg1.value : null;
	var green = arg2 is IntegerLiteral ? arg2.value : null;
	var blue = arg3 is IntegerLiteral ? arg3.value : null;

	return alpha != null && red != null && green != null && blue != null
	? _colorValueForComponents(alpha, red, green, blue)
	: null;
	} else if (name == 'fromRGBO' && args.length == 4) {
	var arg0 = args[0];
	var arg1 = args[1];
	var arg2 = args[2];
	var arg3 = args[3];

	var red = arg0 is IntegerLiteral ? arg0.value : null;
	var green = arg1 is IntegerLiteral ? arg1.value : null;
	var blue = arg2 is IntegerLiteral ? arg2.value : null;
	var opacity = arg3 is IntegerLiteral
	? arg3.value
	: arg3 is DoubleLiteral
	? arg3.value
	: null;
	var alpha = opacity != null ? (opacity * 255).toInt() : null;

	return alpha != null && red != null && green != null && blue != null
	? _colorValueForComponents(alpha, red, green, blue)
	: null;
	} else {
	return null;
	}
	}

	/// Extracts the color value from Flutter MaterialAccentColor constructor args.
	int? _getFlutterMaterialAccentColorValue(String? name, List<Literal?> args) =>
	// MaterialAccentColor is a subclass of SwatchColor and has the same
	// constructor.
	_getFlutterSwatchColorValue(name, args);

	/// Extracts the color value from Flutter ColorSwatch constructor args.
	int? _getFlutterSwatchColorValue(String? name, List<Literal?> args) {
	if (name == null && args.isNotEmpty) {
	var arg0 = args[0];
	return arg0 is IntegerLiteral ? arg0.value : null;
	} else {
	return null;
	}
	}

	/// Extracts a named member from a color.
	///
	/// Well-known getters like `shade500` will be mapped onto the swatch value
	/// with a matching index.
	DartObject? _getMember(DartObject target, String memberName) {
	var colorValue = target.getFieldFromHierarchy(memberName);
	if (colorValue != null) {
	return colorValue;
	}

	// If we didn't get a value but it's a getter we know how to read from a
	// swatch, try that.
	if (memberName.startsWith('shade')) {
	var shadeNumber = int.tryParse(memberName.substring(5));
	if (shadeNumber != null) {
	return _getSwatchValue(target, shadeNumber);
	}
	}

	return null;
	}

	/// Extracts a specific shade index from a Flutter SwatchColor.
	DartObject? _getSwatchValue(DartObject target, int swatchValue) {
	var swatch = target.getFieldFromHierarchy('_swatch')?.toMapValue();
	if (swatch == null) return null;

	var key = swatch.keys.firstWhereOrNull(
	(key) => key?.toIntValue() == swatchValue,
	);
	if (key == null) return null;

	return swatch[key];
	}

	/// Checks whether this elements library is dart:ui.
	bool _isDartUi(Element? element) => element?.library?.name == 'dart.ui';

	/// Checks whether this elements library is Flutter Material colors.
	bool _isFlutterMaterial(Element? element) =>
	element?.library?.identifier ==
	'package:flutter/src/material/colors.dart';

	/// Checks whether this elements library is Flutter Painting colors.
	bool _isFlutterPainting(Element? element) =>
	element?.library?.identifier ==
	'package:flutter/src/painting/colors.dart';

	/// Tries to record a color value from [colorConst] for [expression].
	///
	/// Returns whether a valid color was found and recorded.
	bool _tryRecordColor(Expression expression, DartObject? colorConst) =>
	_tryRecordColorValue(expression, _colorValueForColorConst(colorConst));

	/// Tries to record the [colorValue] for [expression].
	///
	/// Returns whether a valid color was found and recorded.
	bool _tryRecordColorValue(Expression expression, int? colorValue) {
	if (colorValue == null) return false;

	// Build color information from the Color value.
	var color = _colorInformationForColorValue(colorValue);

	// Record the color against the original entire expression.
	_colors.add(ColorReference(expression.offset, expression.length, color));
	return true;
	}

	static ColorInformation? getColorForValue(DartObject object) {
	if (object.type.isColor) {
	var colorValue = _colorValueForColorConst(object);
	if (colorValue != null) {
	return _colorInformationForColorValue(colorValue);
	}
	}
	return null;
	}

	/// Creates a [ColorInformation] by extracting the argb values from
	/// [value] encoded as 0xAARRGGBB as in the dart:ui Color class.
	static ColorInformation _colorInformationForColorValue(int value) {
	// Extract color information according to dart:ui Color values.
	var alpha = (0xff000000 & value) >> 24;
	var red = (0x00ff0000 & value) >> 16;
	var blue = (0x000000ff & value) >> 0;
	var green = (0x0000ff00 & value) >> 8;

	return ColorInformation(alpha, red, green, blue);
	}

	/// Extracts the integer color value from the dart:ui Color constant [color].
	static int? _colorValueForColorConst(DartObject? color) {
	if (color == null \|\| color.isNull) return null;

	// If the object has a "color" field, walk down to that, because some colors
	// like CupertinoColors have a "value=0" with an overridden getter that
	// would always result in a value representing black.
	color = color.getFieldFromHierarchy('color') ?? color;

	return color.getFieldFromHierarchy('value')?.toIntValue();
	}
	}

	/// Information about a color that is present in a document.
	class ColorInformation {
	final int alpha;
	final int red;
	final int green;
	final int blue;

	ColorInformation(this.alpha, this.red, this.green, this.blue);
	}

	/// Information about a specific known location of a [ColorInformation]
	/// reference in a document.
	class ColorReference {
	final int offset;
	final int length;
	final ColorInformation color;

	ColorReference(this.offset, this.length, this.color);
	}

	class _ColorBuilder extends RecursiveAstVisitor<void> {
	final ColorComputer computer;

	_ColorBuilder(this.computer);

	@override
	void visitIndexExpression(IndexExpression node) {
	// Colors.redAccent[500].
	var index = node.index;
	var indexValue = index is IntegerLiteral ? index.value : null;
	if (indexValue != null) {
	if (computer.tryAddColor(
	node,
	target: node.realTarget,
	index: indexValue,
	)) {
	return;
	}
	}
	super.visitIndexExpression(node);
	}

	@override
	void visitInstanceCreationExpression(InstanceCreationExpression node) {
	// Usually we return after finding a color, but constructors can
	// have nested colors in their arguments so we walk all the way down.
	if (!computer.tryAddColor(node)) {
	// If we couldn't evaluate the constant, try the well-known color
	// constructors for dart:ui/Flutter.
	computer.tryAddKnownColorConstructor(node);
	}

	super.visitInstanceCreationExpression(node);
	}

	@override
	void visitPrefixedIdentifier(PrefixedIdentifier node) {
	// Try the whole node as a constant (eg. `MyThemeClass.staticField`).
	if (computer.tryAddColor(node)) {
	return;
	}

	// Try a field of a static, (eg. `const MyThemeClass().instanceField`).
	if (computer.tryAddColor(
	node,
	target: node.prefix,
	memberName: node.identifier.name,
	)) {
	return;
	}

	super.visitPrefixedIdentifier(node);
	}

	@override
	void visitPropertyAccess(PropertyAccess node) {
	// Handle things like CupterinoColors.activeBlue.darkColor where we can't
	// evaluate the whole expression, but can evaluate CupterinoColors.activeBlue
	// and read the darkColor.
	if (computer.tryAddColor(
	node,
	target: node.realTarget,
	memberName: node.propertyName.name,
	)) {
	return;
	}

	super.visitPropertyAccess(node);
	}

	@override
	void visitSimpleIdentifier(SimpleIdentifier node) {
	computer.tryAddColor(node);

	super.visitSimpleIdentifier(node);
	}
	}

	extension _DartObjectExtensions on DartObject {
	/// Reads the value of the field [field] from this object.
	///
	/// If the field is not found, recurses up the super classes.
	DartObject? getFieldFromHierarchy(String fieldName) =>
	getField(fieldName) ??
	getField(GenericState.SUPERCLASS_FIELD)?.getFieldFromHierarchy(fieldName);
	}