| // Copyright (c) 2012, 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. |
| |
| /** |
| * Tests for the toString methods on collections and maps. |
| */ |
| |
| library collection_to_string; |
| |
| import "package:expect/expect.dart"; |
| import 'dart:collection' show Queue, LinkedHashMap; |
| import 'dart:math' as Math; |
| |
| // TODO(jjb): seed random number generator when API allows it |
| |
| const int NUM_TESTS = 300; |
| const int MAX_COLLECTION_SIZE = 7; |
| |
| final rand = Math.Random(); |
| |
| main() { |
| smokeTest(); |
| exactTest(); |
| inexactTest(); |
| } |
| |
| /** |
| * Test a few simple examples. |
| */ |
| void smokeTest() { |
| // Non-const lists |
| Expect.equals([].toString(), '[]'); |
| Expect.equals([1].toString(), '[1]'); |
| Expect.equals(['Elvis'].toString(), '[Elvis]'); |
| Expect.equals([null].toString(), '[null]'); |
| Expect.equals([1, 2].toString(), '[1, 2]'); |
| Expect.equals(['I', 'II'].toString(), '[I, II]'); |
| Expect.equals( |
| [ |
| [1, 2], |
| [3, 4], |
| [5, 6] |
| ].toString(), |
| '[[1, 2], [3, 4], [5, 6]]'); |
| |
| // Const lists |
| Expect.equals((const []).toString(), '[]'); |
| Expect.equals((const [1]).toString(), '[1]'); |
| Expect.equals((const ['Elvis']).toString(), '[Elvis]'); |
| Expect.equals((const [null]).toString(), '[null]'); |
| Expect.equals((const [1, 2]).toString(), '[1, 2]'); |
| Expect.equals((const ['I', 'II']).toString(), '[I, II]'); |
| Expect.equals( |
| (const [ |
| const [1, 2], |
| const [3, 4], |
| const [5, 6] |
| ]) |
| .toString(), |
| '[[1, 2], [3, 4], [5, 6]]'); |
| |
| // Non-const maps - Note that all keys are strings; the spec currently demands this |
| Expect.equals({}.toString(), '{}'); |
| Expect.equals({'Elvis': 'King'}.toString(), '{Elvis: King}'); |
| Expect.equals({'Elvis': null}.toString(), '{Elvis: null}'); |
| Expect.equals({'I': 1, 'II': 2}.toString(), '{I: 1, II: 2}'); |
| Expect.equals( |
| { |
| 'X': {'I': 1, 'II': 2}, |
| 'Y': {'III': 3, 'IV': 4}, |
| 'Z': {'V': 5, 'VI': 6} |
| }.toString(), |
| '{X: {I: 1, II: 2}, Y: {III: 3, IV: 4}, Z: {V: 5, VI: 6}}'); |
| |
| // Const maps |
| Expect.equals(const {}.toString(), '{}'); |
| Expect.equals(const {'Elvis': 'King'}.toString(), '{Elvis: King}'); |
| Expect.equals({'Elvis': null}.toString(), '{Elvis: null}'); |
| Expect.equals(const {'I': 1, 'II': 2}.toString(), '{I: 1, II: 2}'); |
| Expect.equals( |
| const { |
| 'X': const {'I': 1, 'II': 2}, |
| 'Y': const {'III': 3, 'IV': 4}, |
| 'Z': const {'V': 5, 'VI': 6} |
| }.toString(), |
| '{X: {I: 1, II: 2}, Y: {III: 3, IV: 4}, Z: {V: 5, VI: 6}}'); |
| } |
| |
| // SERIOUS "BASHER" TESTS |
| |
| /** |
| * Generate a bunch of random collections (including Maps), and test that |
| * there string form is as expected. The collections include collections |
| * as elements, keys, and values, and include recursive references. |
| * |
| * This test restricts itself to collections with well-defined iteration |
| * orders (i.e., no HashSet, HashMap). |
| */ |
| void exactTest() { |
| for (int i = 0; i < NUM_TESTS; i++) { |
| // Choose a size from 0 to MAX_COLLECTION_SIZE, favoring larger sizes |
| int size = |
| Math.sqrt(random(MAX_COLLECTION_SIZE * MAX_COLLECTION_SIZE)).toInt(); |
| |
| StringBuffer stringRep = new StringBuffer(); |
| Object o = randomCollection(size, stringRep, exact: true); |
| print(stringRep); |
| print(o); |
| Expect.equals(o.toString(), stringRep.toString()); |
| } |
| } |
| |
| /** |
| * Generate a bunch of random collections (including Maps), and test that |
| * there string form is as expected. The collections include collections |
| * as elements, keys, and values, and include recursive references. |
| * |
| * This test includes collections with ill-defined iteration orders (i.e., |
| * HashSet, HashMap). As a consequence, it can't use equality tests on the |
| * string form. Instead, it performs equality tests on their "alphagrams." |
| * This might allow false positives, but it does give a fair amount of |
| * confidence. |
| */ |
| void inexactTest() { |
| for (int i = 0; i < NUM_TESTS; i++) { |
| // Choose a size from 0 to MAX_COLLECTION_SIZE, favoring larger sizes |
| int size = |
| Math.sqrt(random(MAX_COLLECTION_SIZE * MAX_COLLECTION_SIZE)).toInt(); |
| |
| StringBuffer stringRep = new StringBuffer(); |
| Object o = randomCollection(size, stringRep, exact: false); |
| print(stringRep); |
| print(o); |
| Expect.equals(alphagram(o.toString()), alphagram(stringRep.toString())); |
| } |
| } |
| |
| /** |
| * Return a random collection (or Map) of the specified size, placing its |
| * string representation into the given string buffer. |
| * |
| * If exact is true, the returned collections will not be, and will not contain |
| * a collection with ill-defined iteration order (i.e., a HashSet or HashMap). |
| */ |
| Object randomCollection(int size, StringBuffer stringRep, {bool exact = false}) { |
| return randomCollectionHelper(size, exact, stringRep, []); |
| } |
| |
| /** |
| * Return a random collection (or map) of the specified size, placing its |
| * string representation into the given string buffer. The beingMade |
| * parameter is a list of collections currently under construction, i.e., |
| * candidates for recursive references. |
| * |
| * If exact is true, the returned collections will not be, and will not contain |
| * a collection with ill-defined iteration order (i.e., a HashSet or HashMap). |
| */ |
| Object randomCollectionHelper( |
| int size, bool exact, StringBuffer stringRep, List beingMade) { |
| double interfaceFrac = rand.nextDouble(); |
| |
| if (exact) { |
| if (interfaceFrac < 1 / 3) { |
| return randomList(size, exact, stringRep, beingMade); |
| } else if (interfaceFrac < 2 / 3) { |
| return randomQueue(size, exact, stringRep, beingMade); |
| } else { |
| return randomMap(size, exact, stringRep, beingMade); |
| } |
| } else { |
| if (interfaceFrac < 1 / 4) { |
| return randomList(size, exact, stringRep, beingMade); |
| } else if (interfaceFrac < 2 / 4) { |
| return randomQueue(size, exact, stringRep, beingMade); |
| } else if (interfaceFrac < 3 / 4) { |
| return randomSet(size, exact, stringRep, beingMade); |
| } else { |
| return randomMap(size, exact, stringRep, beingMade); |
| } |
| } |
| } |
| |
| /** |
| * Return a random List of the specified size, placing its string |
| * representation into the given string buffer. The beingMade |
| * parameter is a list of collections currently under construction, i.e., |
| * candidates for recursive references. |
| * |
| * If exact is true, the returned collections will not be, and will not contain |
| * a collection with ill-defined iteration order (i.e., a HashSet or HashMap). |
| */ |
| List randomList(int size, bool exact, StringBuffer stringRep, List beingMade) { |
| return populateRandomCollection(size, exact, stringRep, beingMade, [], "[]"); |
| } |
| |
| /** |
| * Like randomList, but returns a queue. |
| */ |
| Queue randomQueue( |
| int size, bool exact, StringBuffer stringRep, List beingMade) { |
| return populateRandomCollection( |
| size, exact, stringRep, beingMade, new Queue(), "{}"); |
| } |
| |
| /** |
| * Like randomList, but returns a Set. |
| */ |
| Set randomSet(int size, bool exact, StringBuffer stringRep, List beingMade) { |
| // Until we have LinkedHashSet, method will only be called with exact==true |
| return populateRandomSet(size, exact, stringRep, beingMade, new Set()); |
| } |
| |
| /** |
| * Like randomList, but returns a map. |
| */ |
| Map randomMap(int size, bool exact, StringBuffer stringRep, List beingMade) { |
| if (exact) { |
| return populateRandomMap( |
| size, exact, stringRep, beingMade, new LinkedHashMap()); |
| } else { |
| return populateRandomMap(size, exact, stringRep, beingMade, |
| randomBool() ? new Map() : new LinkedHashMap()); |
| } |
| } |
| |
| /** |
| * Populates the given empty collection with elements, emitting the string |
| * representation of the collection to stringRep. The beingMade parameter is |
| * a list of collections currently under construction, i.e., candidates for |
| * recursive references. |
| * |
| * If exact is true, the elements of the returned collections will not be, |
| * and will not contain a collection with ill-defined iteration order |
| * (i.e., a HashSet or HashMap). |
| */ |
| populateRandomCollection(int size, bool exact, StringBuffer stringRep, |
| List beingMade, var coll, String delimiters) { |
| beingMade.add(coll); |
| int start = stringRep.length; |
| |
| stringRep.write(delimiters[0]); |
| |
| List<int> indices = []; |
| for (int i = 0; i < size; i++) { |
| indices.add(stringRep.length); |
| if (i != 0) stringRep.write(', '); |
| coll.add(randomElement(random(size), exact, stringRep, beingMade)); |
| } |
| if (size > 5 && delimiters == "()") { |
| const int MAX_LENGTH = 80; |
| const int MIN_COUNT = 3; |
| const int MAX_COUNT = 100; |
| // It's an iterable, it may omit some elements. |
| int end = stringRep.length; |
| if (size > MAX_COUNT) { |
| // Last two elements are also omitted, just find the first three or |
| // first 60 characters. |
| for (int i = MIN_COUNT; i < size; i++) { |
| int startIndex = indices[i]; |
| if (startIndex - start > MAX_LENGTH - 6) { |
| // Limit - ", ...)".length. |
| String prefix = stringRep.toString().substring(0, startIndex); |
| stringRep.clear(); |
| stringRep.write(prefix); |
| stringRep.write(", ..."); |
| } |
| } |
| } else if (stringRep.length - start > MAX_LENGTH - 1) { |
| // 80 - ")".length. |
| // Last two elements are always included. Middle ones may be omitted. |
| int lastTwoLength = end - indices[indices.length - 2]; |
| // Try to find first element to omit. |
| for (int i = 3; i <= size - 3; i++) { |
| int elementEnd = indices[i + 1]; |
| int lengthAfter = elementEnd - start; |
| int ellipsisSize = 5; // ", ...".length |
| if (i == size - 3) ellipsisSize = 0; // No ellipsis if we hit the end. |
| if (lengthAfter + ellipsisSize + lastTwoLength > MAX_LENGTH - 1) { |
| // Omit this element and everything up to the last two. |
| int elementStart = indices[i]; |
| // Rewrite string buffer by copying it out, clearing, and putting |
| // the parts back in. |
| String buffer = stringRep.toString(); |
| String prefix = buffer.substring(0, elementStart); |
| String suffix = buffer.substring(end - lastTwoLength, end); |
| stringRep.clear(); |
| stringRep.write(prefix); |
| stringRep.write(", ..."); |
| stringRep.write(suffix); |
| break; |
| } |
| } |
| } |
| } |
| |
| stringRep.write(delimiters[1]); |
| beingMade.removeLast(); |
| return coll; |
| } |
| |
| /** Like populateRandomCollection, but for sets (elements must be hashable) */ |
| Set populateRandomSet( |
| int size, bool exact, StringBuffer stringRep, List beingMade, Set set) { |
| stringRep.write('{'); |
| |
| for (int i = 0; i < size; i++) { |
| if (i != 0) stringRep.write(', '); |
| set.add(i); |
| stringRep.write(i); |
| } |
| |
| stringRep.write('}'); |
| return set; |
| } |
| |
| /** Like populateRandomCollection, but for maps. */ |
| Map populateRandomMap( |
| int size, bool exact, StringBuffer stringRep, List beingMade, Map map) { |
| beingMade.add(map); |
| stringRep.write('{'); |
| |
| for (int i = 0; i < size; i++) { |
| if (i != 0) stringRep.write(', '); |
| |
| int key = i; // Ensures no duplicates |
| stringRep.write(key); |
| stringRep.write(': '); |
| Object val = randomElement(random(size), exact, stringRep, beingMade); |
| map[key] = val; |
| } |
| |
| stringRep.write('}'); |
| beingMade.removeLast(); |
| return map; |
| } |
| |
| /** |
| * Generates a random element which can be an int, a collection, or a map, |
| * and emits it to StringRep. The beingMade parameter is a list of collections |
| * currently under construction, i.e., candidates for recursive references. |
| * |
| * If exact is true, the returned element will not be, and will not contain |
| * a collection with ill-defined iteration order (i.e., a HashSet or HashMap). |
| */ |
| Object randomElement( |
| int size, bool exact, StringBuffer stringRep, List beingMade) { |
| Object result; |
| double elementTypeFrac = rand.nextDouble(); |
| if (elementTypeFrac < 1 / 3) { |
| result = random(1000); |
| stringRep.write(result); |
| } else if (elementTypeFrac < 2 / 3) { |
| // Element is a random (new) collection |
| result = randomCollectionHelper(size, exact, stringRep, beingMade); |
| } else { |
| // Element is a random recursive ref |
| result = beingMade[random(beingMade.length)]; |
| if (result is List) { |
| stringRep.write('[...]'); |
| } else if (result is Set || result is Map || result is Queue) { |
| stringRep.write('{...}'); |
| } else { |
| stringRep.write('(...)'); |
| } |
| } |
| return result; |
| } |
| |
| /** Returns a random int on [0, max) */ |
| int random(int max) { |
| return rand.nextInt(max); |
| } |
| |
| /** Returns a random boolean value. */ |
| bool randomBool() { |
| return rand.nextBool(); |
| } |
| |
| /** Returns the alphabetized characters in a string. */ |
| String alphagram(String s) { |
| // Calling [toList] to convert unmodifiable list to normal list. |
| List<int> chars = s.codeUnits.toList(); |
| chars.sort((int a, int b) => a - b); |
| return new String.fromCharCodes(chars); |
| } |