assert: improve partialDeepStrictEqual performance and add benchmark

puskin · puskin · commit 4502b7607bdb · 2025-03-03T23:27:56.000+01:00
diff --git a/benchmark/assert/partial-deep-strict-equal.js b/benchmark/assert/partial-deep-strict-equal.js
@@ -0,0 +1,148 @@
+'use strict';
+
+const common = require('../common.js');
+const assert = require('assert');
+
+const bench = common.createBenchmark(main, {
+  n: [10, 50, 200],
+  size: [1e3],
+  datasetName: [
+    'objects',
+    'sets',
+    'maps',
+    'circularRefs',
+    'typedArrays',
+    'arrayBuffers',
+    'dataViewArrayBuffers',
+  ],
+});
+
+function createObjects(length, depth = 0) {
+  return Array.from({ length }, () => ({
+    foo: 'yarp',
+    nope: {
+      bar: '123',
+      a: [1, 2, 3],
+      c: {},
+      b: !depth ? createObjects(2, depth + 1) : [],
+    },
+  }));
+}
+
+function createSets(length, depth = 0) {
+  return Array.from({ length }, () => new Set([
+    'yarp',
+    '123',
+    1,
+    2,
+    3,
+    null,
+    {
+      simple: 'object',
+      number: 42,
+    },
+    ['array', 'with', 'values'],
+    !depth ? new Set([1, 2, { nested: true }]) : new Set(),
+    !depth ? createSets(2, depth + 1) : null,
+  ]));
+}
+
+function createMaps(length, depth = 0) {
+  return Array.from({ length }, () => new Map([
+    ['primitiveKey', 'primitiveValue'],
+    [42, 'numberKey'],
+    ['objectValue', { a: 1, b: 2 }],
+    ['arrayValue', [1, 2, 3]],
+    ['nestedMap', new Map([['a', 1], ['b', { deep: true }]])],
+    [{ objectKey: true }, 'value from object key'],
+    [[1, 2, 3], 'value from array key'],
+    [!depth ? createMaps(2, depth + 1) : null, 'recursive value'],
+  ]));
+}
+
+function createCircularRefs(length) {
+  return Array.from({ length }, () => {
+    const circularSet = new Set();
+    const circularMap = new Map();
+    const circularObj = { name: 'circular object' };
+
+    circularSet.add('some value');
+    circularSet.add(circularSet);
+
+    circularMap.set('self', circularMap);
+    circularMap.set('value', 'regular value');
+
+    circularObj.self = circularObj;
+
+    const objA = { name: 'A' };
+    const objB = { name: 'B' };
+    objA.ref = objB;
+    objB.ref = objA;
+
+    circularSet.add(objA);
+    circularMap.set('objB', objB);
+
+    return {
+      circularSet,
+      circularMap,
+      circularObj,
+      objA,
+      objB,
+    };
+  });
+}
+
+function createTypedArrays(length) {
+  return Array.from({ length }, () => {
+    const buffer = new ArrayBuffer(32);
+
+    return {
+      int8: new Int8Array(buffer, 0, 4),
+      uint8: new Uint8Array(buffer, 4, 4),
+      uint8Clamped: new Uint8ClampedArray(buffer, 8, 4),
+      int16: new Int16Array([1, 2, 3]),
+      uint16: new Uint16Array([1, 2, 3]),
+      int32: new Int32Array([1, 2, 3]),
+      uint32: new Uint32Array([1, 2, 3]),
+      float32: new Float32Array([1.1, 2.2, 3.3]),
+      float64: new Float64Array([1.1, 2.2, 3.3]),
+      bigInt64: new BigInt64Array([1n, 2n, 3n]),
+      bigUint64: new BigUint64Array([1n, 2n, 3n]),
+    };
+  });
+}
+
+function createArrayBuffers(length) {
+  return Array.from({ length }, (_, n) => new ArrayBuffer(n));
+}
+
+function createDataViewArrayBuffers(length) {
+  return Array.from({ length }, (_, n) => new DataView(new ArrayBuffer(n)));
+}
+
+const datasetMappings = {
+  objects: createObjects,
+  sets: createSets,
+  maps: createMaps,
+  circularRefs: createCircularRefs,
+  typedArrays: createTypedArrays,
+  arrayBuffers: createArrayBuffers,
+  dataViewArrayBuffers: createDataViewArrayBuffers,
+};
+
+function getDatasets(datasetName, size) {
+  return {
+    actual: datasetMappings[datasetName](size),
+    expected: datasetMappings[datasetName](size),
+  };
+}
+
+function main({ size, n, datasetName }) {
+  const { actual, expected } = getDatasets(datasetName, size);
+
+  bench.start();
+  for (let i = 0; i < n; ++i) {
+    assert.partialDeepStrictEqual(actual, expected);
+  }
+  bench.end(n);
+}
diff --git a/lib/assert.js b/lib/assert.js
@@ -23,7 +23,6 @@
 const {
   ArrayBufferIsView,
   ArrayBufferPrototypeGetByteLength,
-  ArrayFrom,
   ArrayIsArray,
   ArrayPrototypeIndexOf,
   ArrayPrototypeJoin,
@@ -395,12 +394,11 @@ function partiallyCompareMaps(actual, expected, comparedObjects) {
   const expectedIterator = FunctionPrototypeCall(SafeMap.prototype[SymbolIterator], expected);
 
   for (const { 0: key, 1: expectedValue } of expectedIterator) {
-    if (!MapPrototypeHas(actual, key)) {
+    const actualValue = MapPrototypeGet(actual, key);
+    if (actualValue === undefined && !MapPrototypeHas(actual, key)) {
       return false;
     }
 
-    const actualValue = MapPrototypeGet(actual, key);
-
     if (!compareBranch(actualValue, expectedValue, comparedObjects)) {
       return false;
     }
@@ -474,28 +472,71 @@ function partiallyCompareArrayBuffersOrViews(actual, expected) {
   return true;
 }
 
+// Adapted version of the "setEquiv" function in lib/internal/util/comparisons.js
 function partiallyCompareSets(actual, expected, comparedObjects) {
   if (SetPrototypeGetSize(expected) > SetPrototypeGetSize(actual)) {
-    return false; // `expected` can't be a subset if it has more elements
+    return false;
   }
 
   if (isDeepEqual === undefined) lazyLoadComparison();
+  let set = null;
 
-  const actualArray = ArrayFrom(FunctionPrototypeCall(SafeSet.prototype[SymbolIterator], actual));
-  const expectedIterator = FunctionPrototypeCall(SafeSet.prototype[SymbolIterator], expected);
-  const usedIndices = new SafeSet();
+  // First, check if elements from expected exist in actual
+  for (const val of expected) {
+    // Fast path: direct inclusion check for both primitives and reference equality
+    if (actual.has(val)) {
+      continue;
+    }
+
+    // For primitives, if not found directly, return false immediately
+    if (typeof val !== 'object' || val === null) {
+      return false;
+    }
 
-  expectedIteration: for (const expectedItem of expectedIterator) {
-    for (let actualIdx = 0; actualIdx < actualArray.length; actualIdx++) {
-      if (!usedIndices.has(actualIdx) && isDeepStrictEqual(actualArray[actualIdx], expectedItem)) {
-        usedIndices.add(actualIdx);
-        continue expectedIteration;
+    if (set === null) {
+      // Special case to avoid set creation for single-element comparison
+      if (SetPrototypeGetSize(expected) === 1) {
+        // Try to find any deep-equal object in actual
+        for (const actualItem of actual) {
+          if (!(typeof actualItem !== 'object' || actualItem === null) && isDeepStrictEqual(actualItem, val)) {
+            return true;
+          }
+        }
+        return false;
       }
+      set = new SafeSet();
     }
-    return false;
+
+    // Add this object for later deep comparison
+    set.add(val);
   }
 
-  return true;
+  // If all items were found directly, we're done
+  if (set === null) {
+    return true;
+  }
+
+  // For remaining objects that need deep comparison
+  for (const actualItem of actual) {
+    // Only consider non-primitive values for deep comparison
+    if (!(typeof actualItem !== 'object' || actualItem === null)) {
+      // Check if this actual item deep-equals any remaining expected item
+      for (const expectedItem of set) {
+        if (isDeepStrictEqual(actualItem, expectedItem)) {
+          // Remove the matched item so we don't match it again
+          set.delete(expectedItem);
+          // If all items are matched, we can return early
+          if (set.size === 0) {
+            return true;
+          }
+          break;
+        }
+      }
+    }
+  }
+
+  // If all objects in expected found matches, set will be empty
+  return set.size === 0;
 }
 
 const minusZeroSymbol = Symbol('-0');
@@ -510,21 +551,26 @@ function getZeroKey(item) {
 }
 
 function partiallyCompareArrays(actual, expected, comparedObjects) {
+  if (actual === expected) return true;
+
   if (expected.length > actual.length) {
     return false;
   }
 
+  if (expected.length === 0) {
+    return true;
+  }
+
   if (isDeepEqual === undefined) lazyLoadComparison();
 
   // Create a map to count occurrences of each element in the expected array
   const expectedCounts = new SafeMap();
-  const safeExpected = new SafeArrayIterator(expected);
 
-  for (const expectedItem of safeExpected) {
-    // Check if the item is a zero or a -0, as these need to be handled separately
+  const expectedIterator = new SafeArrayIterator(expected);
+  for (const expectedItem of expectedIterator) {
     if (expectedItem === 0) {
       const zeroKey = getZeroKey(expectedItem);
-      expectedCounts.set(zeroKey, (expectedCounts.get(zeroKey)?.count || 0) + 1);
+      expectedCounts.set(zeroKey, (expectedCounts.get(zeroKey) ?? 0) + 1);
     } else {
       let found = false;
       for (const { 0: key, 1: count } of expectedCounts) {
@@ -540,10 +586,8 @@ function partiallyCompareArrays(actual, expected, comparedObjects) {
     }
   }
 
-  const safeActual = new SafeArrayIterator(actual);
-
-  for (const actualItem of safeActual) {
-    // Check if the item is a zero or a -0, as these need to be handled separately
+  const actualIterator = new SafeArrayIterator(actual);
+  for (const actualItem of actualIterator) {
     if (actualItem === 0) {
       const zeroKey = getZeroKey(actualItem);
 
@@ -567,6 +611,10 @@ function partiallyCompareArrays(actual, expected, comparedObjects) {
         }
       }
     }
+
+    if (expectedCounts.size === 0) {
+      return true;
+    }
   }
 
   return expectedCounts.size === 0;
