Compare commits
3 Commits
e2ba398a62
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main
| Author | SHA1 | Date | |
|---|---|---|---|
| 41b09ae680 | |||
| e00e6fcb1b | |||
| 56b1982f8a |
7
.claude/settings.json
Normal file
7
.claude/settings.json
Normal file
@@ -0,0 +1,7 @@
|
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{
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"permissions": {
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"allow": [
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"Bash(curl -s -w \"\\\\n---HTTP_STATUS:%{http_code}---\" https://raw.githubusercontent.com/kubernetes/kubernetes/master/.markdownlint.yaml)"
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]
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}
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}
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@@ -39,6 +39,14 @@ jobs:
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- name: Run mutation tests
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run: make lint-makefile
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lint-markdown:
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name: Markdown Lint
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runs-on: ubuntu-latest
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steps:
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- uses: actions/checkout@v4
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- uses: DavidAnson/markdownlint-cli2-action@v19
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test-unit:
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name: Unit Tests
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runs-on: ubuntu-latest
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@@ -5,3 +5,5 @@ unleash:
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workers: 4
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dry-run: false
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threshold:
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efficacy: 1.0
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17
.markdownlint.yml
Normal file
17
.markdownlint.yml
Normal file
@@ -0,0 +1,17 @@
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default: true
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heading-style:
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style: atx
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ul-indent:
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indent: 2
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line-length: false
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no-duplicate-heading:
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siblings_only: true
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no-inline-html:
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allowed_elements:
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- br
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- details
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- summary
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- img
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- picture
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- source
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first-line-heading: true
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11
Makefile
11
Makefile
@@ -1,4 +1,4 @@
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.PHONY: all help install clean test-unit test-mutation test-fuzz test docs lint-go lint-makefile lint
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.PHONY: all help install clean test-unit test-mutation test-fuzz test docs lint-go lint-makefile lint-markdown lint
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help: ## Show this help
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@grep -E '^[a-zA-Z_-]+:.*##' $(MAKEFILE_LIST) | awk -F ':.*## ' '{printf " %-15s %s\n", $$1, $$2}'
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@@ -16,10 +16,12 @@ test-unit: ## Run unit tests with coverage
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test-mutation: ## Run mutation tests with gremlins
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gremlins unleash
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FUZZ_TIME ?= 30
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test-fuzz: ## Run all fuzz tests for 30s each
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@for func in $$(grep -r --include='*_test.go' -oh 'func Fuzz\w*' . | sed 's/func //'); do \
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echo "Fuzzing $$func..."; \
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go test ./... -fuzz="^$$func$$" -fuzztime=30s; \
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go test ./... -fuzz="^$$func$$" -fuzztime=$(FUZZ_TIME)s; \
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done
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test: test-unit test-mutation test-fuzz ## Run all tests
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@@ -30,7 +32,10 @@ lint-go: ## Lint Go code
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lint-makefile: ## Lint the Makefile
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checkmake Makefile
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lint: lint-go lint-makefile ## Lint all code
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lint-markdown: ## Lint Markdown files
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docker run --rm -v $(CURDIR):/workdir davidanson/markdownlint-cli2 "**/*.md"
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lint: lint-go lint-makefile lint-markdown ## Lint all code
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docs: ## Serve godoc locally
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@echo ">>> Visit: http://localhost:6060/pkg/$$(go list -m)"
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@@ -1,3 +1,3 @@
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# go-cuckoo
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# <img height="30" src="assets/logo.svg" alt="Go Cuckoo, by `mvhutz`."> Go Cuckoo
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A hash table that uses cuckoo hashing to achieve a worst-case O(1) lookup time.
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A hash table that uses cuckoo hashing to achieve a worst-case O(1) lookup time. Read more about it in [the package documentation](https://pkg.go.dev/git.maximhutz.com/tools/go-cuckoo).
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1
assets/logo.svg
Normal file
1
assets/logo.svg
Normal file
@@ -0,0 +1 @@
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<svg width="16" height="16" xmlns="http://www.w3.org/2000/svg" shape-rendering="crispEdges"><path fill="#2a1512" d="M3,6h1v1h-1v-1M2,7h1v1h-1v-1M12,7h1v1h-1v-1M1,8h1v1h-1v-1M4,8h1v2h-1v-2M14,8h1v1h-1v-1M11,9h1v2h-2v-1h1v-1M5,10h1v1h-1v-1M1,13h2v1h1v1h-2v-1h-1v-1M13,13h2v1h-1v1h-1v1h-1v-2h1v-1M4,15h1v1h-1v-1"/><path fill="#38231f" d="M4,6h1v1h-1v-1M11,6h1v1h-1v-1M13,7h1v1h-1v-1M1,9h1v2h-1v-2M14,9h1v1h-1v-1M14,11h1v2h-1v-2M1,12h1v1h-1v-1M5,15h3v1h-3v-1M10,15h2v1h-2v-1"/><path fill="#3f3f74" d="M7,3h2v1h-2v-1M6,4h1v1h-1v-1M9,4h1v1h-1v-1M5,5h1v5h-1v-5M10,5h1v5h-1v-5M6,10h4v1h-4v-1"/><path fill="#6262ab" d="M9,5h1v1h-1v-1M6,9h1v1h-1v-1M9,9h1v1h-1v-1"/><path fill="#663931" d="M11,8h1v1h-1v-1M2,9h1v1h-1v-1M14,10h1v1h-1v-1M1,11h1v1h-1v-1M3,11h2v1h-2v-1M13,11h1v1h-1v-1M2,12h1v1h-1v-1M5,12h1v1h-1v-1M10,12h3v2h-1v-1h-2v-1M3,13h1v1h-1v-1M8,13h2v1h-2v-1M4,14h3v1h-3v-1M10,14h2v1h-2v-1M8,15h2v1h-2v-1"/><path fill="#8d8dcb" d="M9,6h1v3h-1v1h-2v-1h1v-1h1v-2M6,8h1v1h-1v-1"/><path fill="#8f563b" d="M2,8h1v1h-1v-1M12,9h1v1h-1v-1M2,10h1v1h-1v-1M13,10h1v1h-1v-1M7,11h1v1h-1v-1M11,11h2v1h-2v-1M4,12h1v1h1v-1h1v2h-3v-2M13,12h1v1h-1v-1M10,13h2v1h-2v-1M7,14h3v1h-3v-1"/><path fill="#a4a4d5" d="M8,4h1v4h-1v1h-1v-1h-1v-2h1v-1h1v-1"/><path fill="#ab764a" d="M4,7h1v1h-1v-1M3,8h1v2h-1v-2M12,10h1v1h-1v-1M2,11h1v1h-1v-1M8,11h1v1h-1v-1M3,12h1v1h-1v-1M7,12h1v2h-1v-2"/><path fill="#cacaea" d="M7,4h1v1h-1v-1M6,5h1v1h-1v-1"/><path fill="#d9a066" d="M3,7h1v1h-1v-1M11,7h1v1h-1v-1M12,8h2v2h-1v-1h-1v-1M3,10h2v1h-2v-1M5,11h2v1h-2v-1M9,11h2v1h-1v1h-2v-1h1v-1"/></svg>
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|
After Width: | Height: | Size: 1.5 KiB |
BIN
assets/logo128x128.png
Normal file
BIN
assets/logo128x128.png
Normal file
Binary file not shown.
|
After Width: | Height: | Size: 963 B |
BIN
assets/logo16x16.png
Normal file
BIN
assets/logo16x16.png
Normal file
Binary file not shown.
|
After Width: | Height: | Size: 418 B |
30
bucket.go
30
bucket.go
@@ -17,15 +17,37 @@ type bucket[K, V any] struct {
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compare EqualFunc[K]
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}
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// location determines where in the bucket a certain key would be placed. If the
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// capacity is 0, this will panic.
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func (b bucket[K, V]) location(key K) uint64 {
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return b.hash(key) % b.capacity
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}
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func (b bucket[K, V]) get(key K) (value V, found bool) {
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if b.capacity == 0 {
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return
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}
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slot := b.slots[b.location(key)]
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return slot.value, slot.occupied && b.compare(slot.key, key)
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}
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func (b *bucket[K, V]) drop(key K) (occupied bool) {
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if b.capacity == 0 {
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return
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}
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slot := &b.slots[b.location(key)]
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if slot.occupied && b.compare(slot.key, key) {
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slot.occupied = false
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b.size--
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return true
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}
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return false
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}
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func (b *bucket[K, V]) resize(capacity uint64) {
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b.slots = make([]slot[K, V], capacity)
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b.capacity = capacity
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@@ -33,6 +55,10 @@ func (b *bucket[K, V]) resize(capacity uint64) {
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}
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func (b bucket[K, V]) update(key K, value V) (updated bool) {
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if b.capacity == 0 {
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return
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}
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slot := &b.slots[b.location(key)]
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if slot.occupied && b.compare(slot.key, key) {
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@@ -44,6 +70,10 @@ func (b bucket[K, V]) update(key K, value V) (updated bool) {
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}
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func (b *bucket[K, V]) evict(insertion entry[K, V]) (evicted entry[K, V], eviction bool) {
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if b.capacity == 0 {
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return insertion, true
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}
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slot := &b.slots[b.location(insertion.key)]
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if !slot.occupied {
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@@ -1,11 +1,11 @@
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package cuckoo_test
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import (
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"bytes"
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"encoding/binary"
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"maps"
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"testing"
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"github.com/stretchr/testify/assert"
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go_fuzz_utils "github.com/trailofbits/go-fuzz-utils"
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"git.maximhutz.com/tools/go-cuckoo"
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)
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@@ -19,31 +19,60 @@ func offsetHash(seed uint32) cuckoo.Hash[uint32] {
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}
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}
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type fuzzStep struct {
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drop bool
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key, value uint32
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}
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type fuzzScenario struct {
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seedA, seedB uint32
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steps []fuzzStep
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}
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func FuzzInsertLookup(f *testing.F) {
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f.Fuzz(func(t *testing.T, data []byte, seedA, seedB uint32) {
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f.Fuzz(func(t *testing.T, data []byte) {
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var scenario fuzzScenario
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assert := assert.New(t)
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table := cuckoo.NewCustomTable[uint32, uint32](
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offsetHash(seedA),
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offsetHash(seedB),
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func(a, b uint32) bool { return a == b },
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)
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if seedA == seedB {
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if tp, err := go_fuzz_utils.NewTypeProvider(data); err != nil {
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return
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} else if err := tp.Fill(&scenario); err != nil {
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return
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}
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r := bytes.NewReader(data)
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var key, value uint32
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for binary.Read(r, binary.LittleEndian, &key) == nil &&
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binary.Read(r, binary.LittleEndian, &value) == nil {
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if scenario.seedA == scenario.seedB {
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return
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}
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err := table.Put(key, value)
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assert.NoError(err)
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actual := cuckoo.NewCustomTable[uint32, uint32](
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offsetHash(scenario.seedA),
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offsetHash(scenario.seedB),
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func(a, b uint32) bool { return a == b },
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)
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found, err := table.Get(key)
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assert.NoError(err)
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assert.Equal(value, found)
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expected := map[uint32]uint32{}
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|
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for _, step := range scenario.steps {
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if step.drop {
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err := actual.Drop(step.key)
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assert.NoError(err)
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|
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delete(expected, step.key)
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_, err = actual.Get(step.key)
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assert.Error(err)
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} else {
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err := actual.Put(step.key, step.value)
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assert.NoError(err)
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|
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expected[step.key] = step.value
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|
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found, err := actual.Get(step.key)
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assert.NoError(err)
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assert.Equal(step.value, found)
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}
|
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|
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assert.Equal(expected, maps.Collect(actual.Entries()))
|
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}
|
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})
|
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}
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|
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@@ -25,6 +25,6 @@ func TestLoad(t *testing.T) {
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for i := range 16 {
|
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err := table.Put(i, true)
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assert.NoError(err)
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assert.Equal(float64(table.Size())/float64(table.Capacity()), table.load())
|
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assert.Equal(float64(table.Size())/float64(table.TotalCapacity()), table.load())
|
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}
|
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}
|
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|
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115
cuckoo_test.go
115
cuckoo_test.go
@@ -1,6 +1,7 @@
|
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package cuckoo_test
|
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|
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import (
|
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"errors"
|
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"maps"
|
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"math/rand/v2"
|
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"testing"
|
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@@ -64,7 +65,7 @@ func TestStartingCapacity(t *testing.T) {
|
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assert := assert.New(t)
|
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table := cuckoo.NewTable[int, bool](cuckoo.Capacity(64))
|
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|
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assert.Equal(uint64(128), table.Capacity())
|
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assert.Equal(uint64(128), table.TotalCapacity())
|
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}
|
||||
|
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func TestResizeCapacity(t *testing.T) {
|
||||
@@ -74,12 +75,12 @@ func TestResizeCapacity(t *testing.T) {
|
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cuckoo.GrowthFactor(2),
|
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)
|
||||
|
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for table.Capacity() == 16 {
|
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for table.TotalCapacity() == 16 {
|
||||
err := table.Put(rand.Int(), true)
|
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assert.NoError(err)
|
||||
}
|
||||
|
||||
assert.Equal(uint64(32), table.Capacity())
|
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assert.Equal(uint64(32), table.TotalCapacity())
|
||||
}
|
||||
|
||||
func TestPutMany(t *testing.T) {
|
||||
@@ -117,14 +118,112 @@ func TestGetMany(t *testing.T) {
|
||||
}
|
||||
}
|
||||
|
||||
func TestRemove(t *testing.T) {
|
||||
func TestDropExistingItem(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
key, value := 0, true
|
||||
table := cuckoo.NewTable[int, bool]()
|
||||
(table.Put(key, value))
|
||||
|
||||
err := table.Drop(key)
|
||||
|
||||
assert.NoError(err)
|
||||
assert.Equal(0, table.Size())
|
||||
assert.False(table.Has(key))
|
||||
}
|
||||
|
||||
func TestDropNoItem(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
key := 0
|
||||
table := cuckoo.NewTable[int, bool]()
|
||||
|
||||
assert.False(table.Has(0))
|
||||
err := table.Drop(key)
|
||||
|
||||
err := table.Put(0, true)
|
||||
assert.NoError(err)
|
||||
|
||||
assert.True(table.Has(0))
|
||||
assert.Equal(0, table.Size())
|
||||
assert.False(table.Has(key))
|
||||
}
|
||||
|
||||
func TestDropItemCapacity(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
key := 0
|
||||
table := cuckoo.NewTable[int, bool](
|
||||
cuckoo.Capacity(64),
|
||||
cuckoo.GrowthFactor(2),
|
||||
)
|
||||
|
||||
startingCapacity := table.TotalCapacity()
|
||||
err := table.Drop(key)
|
||||
endingCapacity := table.TotalCapacity()
|
||||
|
||||
assert.NoError(err)
|
||||
assert.Equal(0, table.Size())
|
||||
assert.Equal(uint64(128), startingCapacity)
|
||||
assert.Equal(uint64(64), endingCapacity)
|
||||
}
|
||||
|
||||
func TestPutNoCapacity(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
key, value := 0, true
|
||||
table := cuckoo.NewTable[int, bool](
|
||||
cuckoo.Capacity(0),
|
||||
)
|
||||
|
||||
err := table.Put(key, value)
|
||||
|
||||
assert.NoError(err)
|
||||
assert.Equal(1, table.Size())
|
||||
assert.True(table.Has(key))
|
||||
}
|
||||
|
||||
func TestBadHashCapacity(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
table := cuckoo.NewCustomTable[int, bool](
|
||||
func(int) uint64 { return 0 },
|
||||
func(int) uint64 { return 0 },
|
||||
func(a, b int) bool { return a == b },
|
||||
cuckoo.Capacity(20),
|
||||
)
|
||||
|
||||
err1 := table.Put(0, true)
|
||||
err2 := table.Put(1, true)
|
||||
err3 := table.Put(2, true)
|
||||
|
||||
assert.NoError(err1)
|
||||
assert.NoError(err2)
|
||||
assert.Error(err3)
|
||||
|
||||
assert.Equal(uint64(80), table.TotalCapacity())
|
||||
}
|
||||
|
||||
func TestDropResizeCapacity(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
table := cuckoo.NewTable[int, bool](
|
||||
cuckoo.Capacity(10),
|
||||
)
|
||||
|
||||
err1 := table.Put(0, true)
|
||||
err2 := table.Put(1, true)
|
||||
err3 := table.Drop(1)
|
||||
|
||||
assert.NoError(errors.Join(err1, err2, err3))
|
||||
assert.Equal(uint64(20), table.TotalCapacity())
|
||||
}
|
||||
|
||||
func TestNewTableBy(t *testing.T) {
|
||||
type User struct {
|
||||
_ func()
|
||||
id string
|
||||
name string
|
||||
}
|
||||
|
||||
assert := assert.New(t)
|
||||
table := cuckoo.NewTableBy[User, bool](
|
||||
func(u User) string { return u.id },
|
||||
)
|
||||
|
||||
err := table.Put(User{nil, "1", "Robert"}, true)
|
||||
|
||||
assert.NoError(err)
|
||||
assert.Equal(1, table.Size())
|
||||
assert.True(table.Has(User{nil, "1", "Robbie"}))
|
||||
}
|
||||
|
||||
3
go.mod
3
go.mod
@@ -4,8 +4,11 @@ go 1.25.6
|
||||
|
||||
require github.com/stretchr/testify v1.11.1
|
||||
|
||||
require github.com/kr/pretty v0.3.1 // indirect
|
||||
|
||||
require (
|
||||
github.com/davecgh/go-spew v1.1.1 // indirect
|
||||
github.com/pmezard/go-difflib v1.0.0 // indirect
|
||||
github.com/trailofbits/go-fuzz-utils v0.0.0-20260318143407-0907cafe7589
|
||||
gopkg.in/yaml.v3 v3.0.1 // indirect
|
||||
)
|
||||
|
||||
13
go.sum
13
go.sum
@@ -1,10 +1,21 @@
|
||||
github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
|
||||
github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
|
||||
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
|
||||
github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
|
||||
github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
|
||||
github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
|
||||
github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
|
||||
github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=
|
||||
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
|
||||
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
|
||||
github.com/rogpeppe/go-internal v1.9.0 h1:73kH8U+JUqXU8lRuOHeVHaa/SZPifC7BkcraZVejAe8=
|
||||
github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
|
||||
github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
|
||||
github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
|
||||
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
|
||||
github.com/trailofbits/go-fuzz-utils v0.0.0-20260318143407-0907cafe7589 h1:UmBZCTPdDYore2IEHN+U4eIqEaRq6METh9pKiPumkqc=
|
||||
github.com/trailofbits/go-fuzz-utils v0.0.0-20260318143407-0907cafe7589/go.mod h1:zh+T+w9XT/3o4E0WLEGCdmLJ8Yqx/zY3o538tQY3OjY=
|
||||
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
|
||||
gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
|
||||
gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
|
||||
gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
|
||||
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
|
||||
|
||||
62
table.go
62
table.go
@@ -16,9 +16,9 @@ type Table[K, V any] struct {
|
||||
minLoadFactor float64
|
||||
}
|
||||
|
||||
// Capacity returns the number of slots allocated for the [Table]. To get the
|
||||
// TotalCapacity returns the number of slots allocated for the [Table]. To get the
|
||||
// number of slots filled, look at [Table.Size].
|
||||
func (t Table[K, V]) Capacity() uint64 {
|
||||
func (t Table[K, V]) TotalCapacity() uint64 {
|
||||
return t.bucketA.capacity + t.bucketB.capacity
|
||||
}
|
||||
|
||||
@@ -28,25 +28,34 @@ func (t Table[K, V]) Size() int {
|
||||
}
|
||||
|
||||
func log2(n uint64) (m int) {
|
||||
return bits.Len64(n) - 1
|
||||
return max(0, bits.Len64(n)-1)
|
||||
}
|
||||
|
||||
func (t Table[K, V]) maxEvictions() int {
|
||||
return 3 * log2(t.Capacity())
|
||||
return 3 * log2(t.TotalCapacity())
|
||||
}
|
||||
|
||||
func (t Table[K, V]) load() float64 {
|
||||
return float64(t.Size()) / float64(t.Capacity())
|
||||
// When there are no slots in the table, we still treat the load as 100%.
|
||||
// Every slot in the table is full.
|
||||
if t.TotalCapacity() == 0 {
|
||||
return 1.0
|
||||
}
|
||||
|
||||
return float64(t.Size()) / float64(t.TotalCapacity())
|
||||
}
|
||||
|
||||
func (t *Table[K, V]) resize() error {
|
||||
// resize clears all buckets, changes the sizes of them to a specific capacity,
|
||||
// and fills them back up again. It is a helper function for [Table.grow] and
|
||||
// [Table.shrink]; use them instead.
|
||||
func (t *Table[K, V]) resize(capacity uint64) error {
|
||||
entries := make([]entry[K, V], 0, t.Size())
|
||||
for k, v := range t.Entries() {
|
||||
entries = append(entries, entry[K, V]{k, v})
|
||||
}
|
||||
|
||||
t.bucketA.resize(t.growthFactor * t.bucketA.capacity)
|
||||
t.bucketB.resize(t.growthFactor * t.bucketB.capacity)
|
||||
t.bucketA.resize(capacity)
|
||||
t.bucketB.resize(capacity)
|
||||
|
||||
for _, entry := range entries {
|
||||
if err := t.Put(entry.key, entry.value); err != nil {
|
||||
@@ -57,6 +66,26 @@ func (t *Table[K, V]) resize() error {
|
||||
return nil
|
||||
}
|
||||
|
||||
// grow increases the table's capacity by the [Table.growthFactor]. If the
|
||||
// capacity is 0, it increases it to 1.
|
||||
func (t *Table[K, V]) grow() error {
|
||||
var newCapacity uint64
|
||||
|
||||
if t.TotalCapacity() == 0 {
|
||||
newCapacity = 1
|
||||
} else {
|
||||
newCapacity = t.bucketA.capacity * t.growthFactor
|
||||
}
|
||||
|
||||
return t.resize(newCapacity)
|
||||
}
|
||||
|
||||
// shrink reduces the table's capacity by the [Table.growthFactor]. It may
|
||||
// reduce it down to 0.
|
||||
func (t *Table[K, V]) shrink() error {
|
||||
return t.resize(t.bucketA.capacity / t.growthFactor)
|
||||
}
|
||||
|
||||
// Get fetches the value for a key in the [Table]. Returns an error if no value
|
||||
// is found.
|
||||
func (t Table[K, V]) Get(key K) (value V, err error) {
|
||||
@@ -99,10 +128,10 @@ func (t *Table[K, V]) Put(key K, value V) (err error) {
|
||||
}
|
||||
|
||||
if t.load() < t.minLoadFactor {
|
||||
return fmt.Errorf("bad hash: resize on load %d/%d = %f", t.Size(), t.Capacity(), t.load())
|
||||
return fmt.Errorf("bad hash: resize on load %d/%d = %f", t.Size(), t.TotalCapacity(), t.load())
|
||||
}
|
||||
|
||||
if err := t.resize(); err != nil {
|
||||
if err := t.grow(); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
@@ -111,10 +140,15 @@ func (t *Table[K, V]) Put(key K, value V) (err error) {
|
||||
|
||||
// Drop removes a value for a key in the table. Returns an error if its value
|
||||
// cannot be removed.
|
||||
//
|
||||
// Deprecated: Do not use.
|
||||
func (t Table[K, V]) Drop(_ K) {
|
||||
panic("Not implemented")
|
||||
func (t *Table[K, V]) Drop(key K) (err error) {
|
||||
t.bucketA.drop(key)
|
||||
t.bucketB.drop(key)
|
||||
|
||||
if t.load() < t.minLoadFactor {
|
||||
return t.shrink()
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// Entries returns an unordered sequence of all key-value pairs in the table.
|
||||
|
||||
Reference in New Issue
Block a user