pkg/compiler/lib/src/util/util.dart - sdk.git - Git at Google

 // Copyright (c) 2011, 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.

 // @dart=2.12

 library dart2js.util;

 import 'package:front_end/src/api_unstable/dart2js.dart'
     show $BACKSLASH, $CR, $DEL, $DQ, $LF, $LS, $PS, $TAB, Link;

 export 'maplet.dart';
 export 'setlet.dart';

 part 'indentation.dart';

 /// Helper functions for creating hash codes.
 class Hashing {
   /// If an integer is masked by this constant, the result is guaranteed to be
   /// in Smi range.
   static const int SMI_MASK = 0x3fffffff;

   /// Mix the bits of [value] and merge them with [existing].
   static int mixHashCodeBits(int existing, int value) {
     // Spread the bits of value. Try to stay in the 30-bit range to
     // avoid overflowing into a more expensive integer representation.
     int h = value & 0x1fffffff;
     h += ((h & 0x3fff) << 15) ^ 0x1fffcd7d;
     h ^= (h >> 10);
     h += ((h & 0x3ffffff) << 3);
     h ^= (h >> 6);
     h += ((h & 0x7ffffff) << 2) + ((h & 0x7fff) << 14);
     h ^= (h >> 16);
     // Combine the two hash values.
     int high = existing >> 15;
     int low = existing & 0x7fff;
     return ((high * 13) ^ (low * 997) ^ h) & SMI_MASK;
   }

   /// Returns a hash value computed from all the characters in the string.
   static int stringHash(String s) {
     int hash = mixHashCodeBits(0, s.length);
     for (int i = 0; i < s.length; i++) {
       hash = mixHashCodeBits(hash, s.codeUnitAt(i));
     }
     return hash;
   }

   /// Mix the bits of `object.hashCode` with [existing].
   static int objectHash(Object? object, [int existing = 0]) {
     return mixHashCodeBits(existing, object.hashCode);
   }

   /// Mix the bits of `.hashCode` all non-null objects.
   static int objectsHash(Object? obj1,
       [Object? obj2, Object? obj3, Object? obj4, Object? obj5]) {
     int hash = 0;
     if (obj5 != null) hash = objectHash(obj5, hash);
     if (obj4 != null) hash = objectHash(obj4, hash);
     if (obj3 != null) hash = objectHash(obj3, hash);
     if (obj2 != null) hash = objectHash(obj2, hash);
     return objectHash(obj1, hash);
   }

   /// Mix the bits of the element hash codes of [list] with [existing].
   static int listHash(List? list, [int existing = 0]) {
     int h = existing;
     if (list != null) {
       int length = list.length;
       for (int i = 0; i < length; i++) {
         h = mixHashCodeBits(h, list[i].hashCode);
       }
     }
     return h;
   }

   /// Mix the bits of the element hash codes of [iterable] with [existing].
   static int setHash<E>(Iterable<E>? iterable, [int existing = 0]) {
     int h = existing;
     if (iterable != null) {
       for (E e in iterable) {
         h += objectsHash(e);
       }
     }
     return h & SMI_MASK;
   }

   /// Mix the bits of the hash codes of the unordered key/value from [map] with
   /// [existing].
   static int unorderedMapHash(Map map, [int existing = 0]) {
     if (map.length == 0) return existing;
     List<int> hashCodes = List.filled(map.length, 0);
     int i = 0;
     for (var entry in map.entries) {
       hashCodes[i++] = objectHash(entry.key, objectHash(entry.value));
     }
     hashCodes.sort();
     int h = existing;
     for (int hashCode in hashCodes) {
       h = mixHashCodeBits(h, hashCode);
     }
     return h;
   }

   /// Mix the bits of the key/value hash codes from [map] with [existing].
   static int mapHash(Map map, [int existing = 0]) {
     int h = existing;
     for (var key in map.keys) {
       h = mixHashCodeBits(h, key.hashCode);
       h = mixHashCodeBits(h, map[key].hashCode);
     }
     return h;
   }
 }

 bool identicalElements<E>(List<E>? a, List<E>? b) {
   if (identical(a, b)) return true;
   if (a == null || b == null) return false;
   if (a.length != b.length) return false;
   for (int index = 0; index < a.length; index++) {
     if (!identical(a[index], b[index])) {
       return false;
     }
   }
   return true;
 }

 bool equalElements<E>(List<E>? a, List<E>? b) {
   if (identical(a, b)) return true;
   if (a == null || b == null) return false;
   if (a.length != b.length) return false;
   for (int index = 0; index < a.length; index++) {
     if (a[index] != b[index]) {
       return false;
     }
   }
   return true;
 }

 bool equalSets<E>(Set<E>? a, Set<E>? b) {
   if (identical(a, b)) return true;
   if (a == null || b == null) return false;
   return a.length == b.length && a.containsAll(b) && b.containsAll(a);
 }

 bool equalMaps<K, V>(Map<K, V>? a, Map<K, V>? b) {
   if (identical(a, b)) return true;
   if (a == null || b == null) return false;
   if (a.length != b.length) return false;
   for (K key in a.keys) {
     if (a[key] != b[key]) return false;
   }
   return true;
 }

 /// File name prefix used to shorten the file name in stack traces printed by
 /// [trace].
 String? stackTraceFilePrefix = null;

 /// Writes the characters of [string] on [buffer].  The characters
 /// are escaped as suitable for JavaScript and JSON.  [buffer] is
 /// anything which supports [:write:] and [:writeCharCode:], for example,
 /// [StringBuffer].  Note that JS supports \xnn and \unnnn whereas JSON only
 /// supports the \unnnn notation.  Therefore we use the \unnnn notation.
 void writeJsonEscapedCharsOn(String string, buffer) {
   void addCodeUnitEscaped(var buffer, int code) {
     assert(code < 0x10000);
     buffer.write(r'\u');
     if (code < 0x1000) {
       buffer.write('0');
       if (code < 0x100) {
         buffer.write('0');
         if (code < 0x10) {
           buffer.write('0');
         }
       }
     }
     buffer.write(code.toRadixString(16));
   }

   void writeEscapedOn(String string, var buffer) {
     for (int i = 0; i < string.length; i++) {
       int code = string.codeUnitAt(i);
       if (code == $DQ) {
         buffer.write(r'\"');
       } else if (code == $TAB) {
         buffer.write(r'\t');
       } else if (code == $LF) {
         buffer.write(r'\n');
       } else if (code == $CR) {
         buffer.write(r'\r');
       } else if (code == $DEL) {
         addCodeUnitEscaped(buffer, $DEL);
       } else if (code == $LS) {
         // This Unicode line terminator and $PS are invalid in JS string
         // literals.
         addCodeUnitEscaped(buffer, $LS); // 0x2028.
       } else if (code == $PS) {
         addCodeUnitEscaped(buffer, $PS); // 0x2029.
       } else if (code == $BACKSLASH) {
         buffer.write(r'\\');
       } else {
         if (code < 0x20) {
           addCodeUnitEscaped(buffer, code);
           // We emit DEL (ASCII 0x7f) as an escape because it would be confusing
           // to have it unescaped in a string literal.  We also escape
           // everything above 0x7f because that means we don't have to worry
           // about whether the web server serves it up as Latin1 or UTF-8.
         } else if (code < 0x7f) {
           buffer.writeCharCode(code);
         } else {
           // This will output surrogate pairs in the form \udxxx\udyyy, rather
           // than the more logical \u{zzzzzz}.  This should work in JavaScript
           // (especially old UCS-2 based implementations) and is the only
           // format that is allowed in JSON.
           addCodeUnitEscaped(buffer, code);
         }
       }
     }
   }

   for (int i = 0; i < string.length; i++) {
     int code = string.codeUnitAt(i);
     if (code < 0x20 ||
         code == $DEL ||
         code == $DQ ||
         code == $LS ||
         code == $PS ||
         code == $BACKSLASH ||
         code >= 0x80) {
       writeEscapedOn(string, buffer);
       return;
     }
   }
   buffer.write(string);
 }

 int computeHashCode(part1, [part2, part3, part4, part5]) {
   return (part1.hashCode ^
           part2.hashCode ^
           part3.hashCode ^
           part4.hashCode ^
           part5.hashCode) &
       0x3fffffff;
 }

 class Pair<A, B> {
   final A a;
   final B b;

   Pair(this.a, this.b);

   @override
   int get hashCode => 13 * a.hashCode + 17 * b.hashCode;

   @override
   bool operator ==(var other) {
     if (identical(this, other)) return true;
     if (other is! Pair) return false;
     return a == other.a && b == other.b;
   }

   @override
   String toString() => '($a,$b)';
 }

 int longestCommonPrefixLength(List a, List b) {
   int index = 0;
   for (; index < a.length && index < b.length; index++) {
     if (a[index] != b[index]) {
       break;
     }
   }
   return index;
 }

 /// Returns [suggestedName] if it is not in [usedNames]. Otherwise concatenates
 /// the smallest number that makes it not appear in [usedNames].
 ///
 /// Adds the result to [usedNames].
 String makeUnique(String suggestedName, Set<String> usedNames,
     [String separator = '']) {
   String result = suggestedName;
   if (usedNames.contains(suggestedName)) {
     int counter = 0;
     while (usedNames.contains(result)) {
       counter++;
       result = "$suggestedName$separator$counter";
     }
   }
   usedNames.add(result);
   return result;
 }
	// Copyright (c) 2011, 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.

	// @dart=2.12

	library dart2js.util;

	import 'package:front_end/src/api_unstable/dart2js.dart'
	show $BACKSLASH, $CR, $DEL, $DQ, $LF, $LS, $PS, $TAB, Link;

	export 'maplet.dart';
	export 'setlet.dart';

	part 'indentation.dart';

	/// Helper functions for creating hash codes.
	class Hashing {
	/// If an integer is masked by this constant, the result is guaranteed to be
	/// in Smi range.
	static const int SMI_MASK = 0x3fffffff;

	/// Mix the bits of [value] and merge them with [existing].
	static int mixHashCodeBits(int existing, int value) {
	// Spread the bits of value. Try to stay in the 30-bit range to
	// avoid overflowing into a more expensive integer representation.
	int h = value & 0x1fffffff;
	h += ((h & 0x3fff) << 15) ^ 0x1fffcd7d;
	h ^= (h >> 10);
	h += ((h & 0x3ffffff) << 3);
	h ^= (h >> 6);
	h += ((h & 0x7ffffff) << 2) + ((h & 0x7fff) << 14);
	h ^= (h >> 16);
	// Combine the two hash values.
	int high = existing >> 15;
	int low = existing & 0x7fff;
	return ((high * 13) ^ (low * 997) ^ h) & SMI_MASK;
	}

	/// Returns a hash value computed from all the characters in the string.
	static int stringHash(String s) {
	int hash = mixHashCodeBits(0, s.length);
	for (int i = 0; i < s.length; i++) {
	hash = mixHashCodeBits(hash, s.codeUnitAt(i));
	}
	return hash;
	}

	/// Mix the bits of `object.hashCode` with [existing].
	static int objectHash(Object? object, [int existing = 0]) {
	return mixHashCodeBits(existing, object.hashCode);
	}

	/// Mix the bits of `.hashCode` all non-null objects.
	static int objectsHash(Object? obj1,
	[Object? obj2, Object? obj3, Object? obj4, Object? obj5]) {
	int hash = 0;
	if (obj5 != null) hash = objectHash(obj5, hash);
	if (obj4 != null) hash = objectHash(obj4, hash);
	if (obj3 != null) hash = objectHash(obj3, hash);
	if (obj2 != null) hash = objectHash(obj2, hash);
	return objectHash(obj1, hash);
	}

	/// Mix the bits of the element hash codes of [list] with [existing].
	static int listHash(List? list, [int existing = 0]) {
	int h = existing;
	if (list != null) {
	int length = list.length;
	for (int i = 0; i < length; i++) {
	h = mixHashCodeBits(h, list[i].hashCode);
	}
	}
	return h;
	}

	/// Mix the bits of the element hash codes of [iterable] with [existing].
	static int setHash<E>(Iterable<E>? iterable, [int existing = 0]) {
	int h = existing;
	if (iterable != null) {
	for (E e in iterable) {
	h += objectsHash(e);
	}
	}
	return h & SMI_MASK;
	}

	/// Mix the bits of the hash codes of the unordered key/value from [map] with
	/// [existing].
	static int unorderedMapHash(Map map, [int existing = 0]) {
	if (map.length == 0) return existing;
	List<int> hashCodes = List.filled(map.length, 0);
	int i = 0;
	for (var entry in map.entries) {
	hashCodes[i++] = objectHash(entry.key, objectHash(entry.value));
	}
	hashCodes.sort();
	int h = existing;
	for (int hashCode in hashCodes) {
	h = mixHashCodeBits(h, hashCode);
	}
	return h;
	}

	/// Mix the bits of the key/value hash codes from [map] with [existing].
	static int mapHash(Map map, [int existing = 0]) {
	int h = existing;
	for (var key in map.keys) {
	h = mixHashCodeBits(h, key.hashCode);
	h = mixHashCodeBits(h, map[key].hashCode);
	}
	return h;
	}
	}

	bool identicalElements<E>(List<E>? a, List<E>? b) {
	if (identical(a, b)) return true;
	if (a == null \|\| b == null) return false;
	if (a.length != b.length) return false;
	for (int index = 0; index < a.length; index++) {
	if (!identical(a[index], b[index])) {
	return false;
	}
	}
	return true;
	}

	bool equalElements<E>(List<E>? a, List<E>? b) {
	if (identical(a, b)) return true;
	if (a == null \|\| b == null) return false;
	if (a.length != b.length) return false;
	for (int index = 0; index < a.length; index++) {
	if (a[index] != b[index]) {
	return false;
	}
	}
	return true;
	}

	bool equalSets<E>(Set<E>? a, Set<E>? b) {
	if (identical(a, b)) return true;
	if (a == null \|\| b == null) return false;
	return a.length == b.length && a.containsAll(b) && b.containsAll(a);
	}

	bool equalMaps<K, V>(Map<K, V>? a, Map<K, V>? b) {
	if (identical(a, b)) return true;
	if (a == null \|\| b == null) return false;
	if (a.length != b.length) return false;
	for (K key in a.keys) {
	if (a[key] != b[key]) return false;
	}
	return true;
	}

	/// File name prefix used to shorten the file name in stack traces printed by
	/// [trace].
	String? stackTraceFilePrefix = null;

	/// Writes the characters of [string] on [buffer]. The characters
	/// are escaped as suitable for JavaScript and JSON. [buffer] is
	/// anything which supports [:write:] and [:writeCharCode:], for example,
	/// [StringBuffer]. Note that JS supports \xnn and \unnnn whereas JSON only
	/// supports the \unnnn notation. Therefore we use the \unnnn notation.
	void writeJsonEscapedCharsOn(String string, buffer) {
	void addCodeUnitEscaped(var buffer, int code) {
	assert(code < 0x10000);
	buffer.write(r'\u');
	if (code < 0x1000) {
	buffer.write('0');
	if (code < 0x100) {
	buffer.write('0');
	if (code < 0x10) {
	buffer.write('0');
	}
	}
	}
	buffer.write(code.toRadixString(16));
	}

	void writeEscapedOn(String string, var buffer) {
	for (int i = 0; i < string.length; i++) {
	int code = string.codeUnitAt(i);
	if (code == $DQ) {
	buffer.write(r'\"');
	} else if (code == $TAB) {
	buffer.write(r'\t');
	} else if (code == $LF) {
	buffer.write(r'\n');
	} else if (code == $CR) {
	buffer.write(r'\r');
	} else if (code == $DEL) {
	addCodeUnitEscaped(buffer, $DEL);
	} else if (code == $LS) {
	// This Unicode line terminator and $PS are invalid in JS string
	// literals.
	addCodeUnitEscaped(buffer, $LS); // 0x2028.
	} else if (code == $PS) {
	addCodeUnitEscaped(buffer, $PS); // 0x2029.
	} else if (code == $BACKSLASH) {
	buffer.write(r'\\');
	} else {
	if (code < 0x20) {
	addCodeUnitEscaped(buffer, code);
	// We emit DEL (ASCII 0x7f) as an escape because it would be confusing
	// to have it unescaped in a string literal. We also escape
	// everything above 0x7f because that means we don't have to worry
	// about whether the web server serves it up as Latin1 or UTF-8.
	} else if (code < 0x7f) {
	buffer.writeCharCode(code);
	} else {
	// This will output surrogate pairs in the form \udxxx\udyyy, rather
	// than the more logical \u{zzzzzz}. This should work in JavaScript
	// (especially old UCS-2 based implementations) and is the only
	// format that is allowed in JSON.
	addCodeUnitEscaped(buffer, code);
	}
	}
	}
	}

	for (int i = 0; i < string.length; i++) {
	int code = string.codeUnitAt(i);
	if (code < 0x20 \|\|
	code == $DEL \|\|
	code == $DQ \|\|
	code == $LS \|\|
	code == $PS \|\|
	code == $BACKSLASH \|\|
	code >= 0x80) {
	writeEscapedOn(string, buffer);
	return;
	}
	}
	buffer.write(string);
	}

	int computeHashCode(part1, [part2, part3, part4, part5]) {
	return (part1.hashCode ^
	part2.hashCode ^
	part3.hashCode ^
	part4.hashCode ^
	part5.hashCode) &
	0x3fffffff;
	}

	class Pair<A, B> {
	final A a;
	final B b;

	Pair(this.a, this.b);

	@override
	int get hashCode => 13 * a.hashCode + 17 * b.hashCode;

	@override
	bool operator ==(var other) {
	if (identical(this, other)) return true;
	if (other is! Pair) return false;
	return a == other.a && b == other.b;
	}

	@override
	String toString() => '($a,$b)';
	}

	int longestCommonPrefixLength(List a, List b) {
	int index = 0;
	for (; index < a.length && index < b.length; index++) {
	if (a[index] != b[index]) {
	break;
	}
	}
	return index;
	}

	/// Returns [suggestedName] if it is not in [usedNames]. Otherwise concatenates
	/// the smallest number that makes it not appear in [usedNames].
	///
	/// Adds the result to [usedNames].
	String makeUnique(String suggestedName, Set<String> usedNames,
	[String separator = '']) {
	String result = suggestedName;
	if (usedNames.contains(suggestedName)) {
	int counter = 0;
	while (usedNames.contains(result)) {
	counter++;
	result = "$suggestedName$separator$counter";
	}
	}
	usedNames.add(result);
	return result;
	}