feat: initial release

.circleci/config.yml

@@ -0,0 +1,26 @@
+jobs:
+  build:
+    executor:
+      name: go/default
+      tag: '1.21.1'
+    steps:
+      - checkout
+      - go/load-cache
+      - go/mod-download
+      - go/save-cache
+      - go/test:
+          covermode: atomic
+          failfast: true
+          race: true
+          coverprofile: coverage.txt
+      - run:
+          name: Coverage Report
+          command: |
+            bash <(curl -s https://codecov.io/bash)
+orbs:
+  go: circleci/go@1.9.0
+version: 2.1
+workflows:
+  main:
+    jobs:
+      - build

.github/workflows/commit-validation.yaml

@@ -0,0 +1,13 @@
+name: Commit validation
+
+on:
+  [pull_request]
+
+jobs:
+  commitsar:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+
+      - name: Commitsar Action
+        uses: outillage/commitsar@v0.13.0

.github/workflows/golangci-lint.yml

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+name: golangci-lint
+on:
+  push:
+    tags:
+      - v*
+    branches:
+      - master
+  pull_request:
+jobs:
+  golangci:
+    name: lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v2
+        with:
+          # Required: the version of golangci-lint is required and must be specified without patch version: we always use the latest patch version.
+          version: v1.29

.github/workflows/release.yaml

@@ -0,0 +1,36 @@
+name: Release
+
+on:
+  pull_request:
+    branches:
+      - main
+  push:
+    branches:
+      - main
+
+jobs:
+  release:
+    name: release
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Action For Semantic Release
+        uses: cycjimmy/semantic-release-action@v2.3.0
+        id: semantic
+        with:
+          semantic_version: 17
+          extra_plugins: |
+            conventional-changelog-conventionalcommits
+            @semantic-release/changelog
+            @semantic-release/git
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
+
+      - name: Push updates to branch for major version
+        if: steps.semantic.outputs.new_release_published == 'true'
+        run: "git push https://x-access-token:${GITHUB_TOKEN}@github.com/${GITHUB_REPOSITORY}.git HEAD:refs/heads/v${{steps.semantic.outputs.new_release_major_version}}"
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.gitignore

@@ -0,0 +1,24 @@
+# If you prefer the allow list template instead of the deny list, see community template:
+# https://github.com/github/gitignore/blob/main/community/Golang/Go.AllowList.gitignore
+#
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+
+# Go workspace file
+go.work
+
+coverage.txt
+.idea

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2020 Maksim Martianov
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -0,0 +1,97 @@
+[![CircleCI](https://dl.circleci.com/status-badge/img/gh/maksimru/go-option/tree/master.svg?style=svg)](https://dl.circleci.com/status-badge/redirect/gh/maksimru/go-option/tree/master)
+[![codecov](https://codecov.io/gh/maksimru/go-option/graph/badge.svg?token=NQICPHBEUQ)](https://codecov.io/gh/maksimru/go-option)
+[![PkgGoDev](https://pkg.go.dev/badge/github.com/maksimru/go-option)](https://pkg.go.dev/github.com/maksimru/go-option)
+[![Go Report Card](https://goreportcard.com/badge/github.com/maksimru/go-option)](https://goreportcard.com/report/github.com/maksimru/go-option)
+
+# Go Option
+
+The idea is based on Scala Option and Java Optional. The package allows to create optional values in Golang
+
+## Functions
+
+Set an non-empty value:
+```
+option.Some[T](v) 
+```
+
+Set an empty value:
+```
+v := option.None[T]() 
+```
+
+Set an empty value if v is nil, otherwise set non-empty value
+```
+v := option.NewOption[T](v)
+```
+
+Remap one option to another option
+```
+import "github.com/maksimru/go-option"
+
+type Car struct {
+    name        string
+    plateNumber option.Option[string]
+}
+
+carOpt := option.Some[Car](
+    Car {
+        name:        "bmw"
+    },
+)
+
+// get car name as option
+carNameOpt := option.Map[Car, string](carOpt, func(c Car) string {
+   return c.name
+})
+```
+
+Option composition
+```
+import "github.com/maksimru/go-option"
+
+type Car struct {
+    name        string
+    plateNumber option.Option[string]
+}
+
+type User struct {
+    name string
+    car  option.Option[Car]
+}
+
+u := User{
+    name: "jake",
+    car: option.Some[Car](
+        Car{
+            name:        "bmw",
+            plateNumber: option.Some[string]("X723"),
+        },
+    ),
+}
+
+// get car plate as option
+carPlateOpt := option.FlatMap[Car, string](u.car, func(c Car) option.Option[string] {
+    return c.plateNumber
+})
+```
+
+## Methods of Option
+
+| Method |                   Description                   |
+|--------|:-----------------------------------------------:|
+| Get() |         gets underlying value (unsafe*)         |
+| GetOrElse(fallback) | gets underlying value or returns fallback value |
+| OrElse(fallbackOpt) |   returns fallback option if option is empty    |
+| Empty() |            checks if value is empty             |
+| NonEmpty() |             checks if value is set              |
+| String() |              string representation              |
+`* - empty value will panic`
+
+---
+## Testing
+
+To run all tests in this module:
+
+```
+go test ./...
+```

config.go

@@ -0,0 +1 @@
+package option

go.mod

@@ -0,0 +1,11 @@
+module github.com/maksimru/go-option
+
+go 1.21.1
+
+require github.com/stretchr/testify v1.8.4
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

go.sum

@@ -0,0 +1,10 @@
+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/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

none.go

@@ -0,0 +1,28 @@
+package option
+
+type optNone[T any] struct {
+}
+
+func (n optNone[T]) Get() T {
+	panic("called Get on optNone value")
+}
+
+func (n optNone[T]) GetOrElse(v T) T {
+	return v
+}
+
+func (n optNone[T]) OrElse(opt Option[T]) Option[T] {
+	return opt
+}
+
+func (n optNone[T]) Empty() bool {
+	return true
+}
+
+func (n optNone[T]) NonEmpty() bool {
+	return false
+}
+
+func (n optNone[T]) String() string {
+	return "None"
+}