feat(climatecontrol): initial working version

.gitignore

@@ -0,0 +1,4 @@
+/*.tidy-check
+/bin/*
+/coverage.out
+/output.txt

.golangci.yml

@@ -0,0 +1,78 @@
+linters-settings:
+  funlen:
+    lines: 100
+    statements: 150
+  gocyclo:
+    min-complexity: 20
+  golint:
+    min-confidence: 0
+  govet:
+    check-shadowing: true
+    enable-all: true
+  lll:
+    line-length: 80
+    tab-width: 4
+  maligned:
+    suggest-new: true
+  misspell:
+    locale: US
+
+linters:
+  disable-all: true
+  enable:
+    - bodyclose
+    - deadcode
+    - depguard
+    - dupl
+    - errcheck
+    - funlen
+    - gochecknoinits
+    - goconst
+    - gocritic
+    - gocyclo
+    - goerr113
+    - goimports
+    - golint
+    - goprintffuncname
+    - gosec
+    - gosimple
+    - govet
+    - ineffassign
+    - lll
+    - misspell
+    - nakedret
+    - nlreturn
+    - noctx
+    - nolintlint
+    - scopelint
+    - sqlclosecheck
+    - staticcheck
+    - structcheck
+    - typecheck
+    - unconvert
+    - unused
+    - varcheck
+    - whitespace
+
+issues:
+  include:
+  # - EXC0002 # disable excluding of issues about comments from golint
+  exclude:
+    - Using the variable on range scope `tt` in function literal
+    - Using the variable on range scope `tc` in function literal
+  exclude-rules:
+    - path: "_test\\.go"
+      linters:
+        - funlen
+        - dupl
+    - source: "^//go:generate "
+      linters:
+        - lll
+    - source: "`json:"
+      linters:
+        - lll
+
+run:
+  timeout: 2m
+  allow-parallel-runners: true
+  modules-download-mode: readonly

Makefile

@@ -0,0 +1,175 @@
+GOMODNAME := $(shell grep 'module' go.mod | sed -e 's/^module //')
+SOURCES := $(shell find . -name "*.go" -or -name "go.mod" -or -name "go.sum" \
+	-or -name "Makefile")
+
+# Verbose output
+ifdef VERBOSE
+V = -v
+endif
+
+#
+# Environment
+#
+
+BINDIR := bin
+TOOLDIR := $(BINDIR)/tools
+
+# Global environment variables for all targets
+SHELL ?= /bin/bash
+SHELL := env \
+	GO111MODULE=on \
+	GOBIN=$(CURDIR)/$(TOOLDIR) \
+	CGO_ENABLED=1 \
+	PATH='$(CURDIR)/$(BINDIR):$(CURDIR)/$(TOOLDIR):$(PATH)' \
+	$(SHELL)
+
+#
+# Defaults
+#
+
+# Default target
+.DEFAULT_GOAL := test
+
+#
+# Tools
+#
+
+TOOLS += $(TOOLDIR)/gobin
+gobin: $(TOOLDIR)/gobin
+$(TOOLDIR)/gobin:
+	GO111MODULE=off go get -u github.com/myitcv/gobin
+
+# external tool
+define tool # 1: binary-name, 2: go-import-path
+TOOLS += $(TOOLDIR)/$(1)
+
+.PHONY: $(1)
+$(1): $(TOOLDIR)/$(1)
+
+$(TOOLDIR)/$(1): $(TOOLDIR)/gobin Makefile
+	gobin $(V) "$(2)"
+endef
+
+$(eval $(call tool,godoc,golang.org/x/tools/cmd/godoc))
+$(eval $(call tool,gofumports,mvdan.cc/gofumpt/gofumports))
+$(eval $(call tool,golangci-lint,github.com/golangci/golangci-lint/cmd/golangci-lint@v1.35))
+
+.PHONY: tools
+tools: $(TOOLS)
+
+#
+# Development
+#
+
+TEST ?= $$(go list ./... | grep -v 'vendor')
+BENCH ?= .
+
+.PHONY: clean
+clean:
+	rm -f $(TOOLS)
+	rm -f ./coverage.out ./go.mod.tidy-check ./go.sum.tidy-check
+
+.PHONY: clean-golden
+clean-golden:
+	rm -f $(shell find * -path '*/testdata/*' -name "*.golden" \
+		-exec echo "'{}'" \;)
+
+.PHONY: test
+test:
+	go test $(V) -count=1 -race $(TESTARGS) $(TEST)
+
+.PHONY: test-update-golden
+test-update-golden:
+	@$(MAKE) test UPDATE_GOLDEN=1
+
+.PHONY: regen-golden
+regen-golden: clean-golden test-update-golden
+
+.PHONY: test-deps
+test-deps:
+	go test all
+
+.PHONY: lint
+lint: golangci-lint
+	GOGC=off golangci-lint $(V) run
+
+.PHONY: format
+format: gofumports
+	gofumports -w .
+
+.SILENT: bench
+.PHONY: bench
+bench:
+	go test $(V) -count=1 -bench=$(BENCH) $(TESTARGS) $(TEST)
+
+#
+# Coverage
+#
+
+.PHONY: cov
+cov: coverage.out
+
+.PHONY: cov-html
+cov-html: coverage.out
+	go tool cover -html=./coverage.out
+
+.PHONY: cov-func
+cov-func: coverage.out
+	go tool cover -func=./coverage.out
+
+coverage.out: $(SOURCES)
+	go test $(V) -covermode=count -coverprofile=./coverage.out ./...
+
+#
+# Dependencies
+#
+
+.PHONY: deps
+deps:
+	$(info Downloading dependencies)
+	go mod download
+
+.PHONY: tidy
+tidy:
+	go mod tidy $(V)
+
+.PHONY: verify
+verify:
+	go mod verify
+
+.SILENT: check-tidy
+.PHONY: check-tidy
+check-tidy:
+	cp go.mod go.mod.tidy-check
+	cp go.sum go.sum.tidy-check
+	go mod tidy
+	( \
+		diff go.mod go.mod.tidy-check && \
+		diff go.sum go.sum.tidy-check && \
+		rm -f go.mod go.sum && \
+		mv go.mod.tidy-check go.mod && \
+		mv go.sum.tidy-check go.sum \
+	) || ( \
+		rm -f go.mod go.sum && \
+		mv go.mod.tidy-check go.mod && \
+		mv go.sum.tidy-check go.sum; \
+		exit 1 \
+	)
+
+#
+# Documentation
+#
+
+# Serve docs
+.PHONY: docs
+docs: godoc
+	$(info serviing docs on http://127.0.0.1:6060/pkg/$(GOMODNAME)/)
+	@godoc -http=127.0.0.1:6060
+
+#
+# Release
+#
+
+.PHONY: new-version
+new-version:
+	npx standard-version

climatecontrol.go

@@ -0,0 +1,77 @@
+// Package climatecontrol provides test helper functions which temporary changes
+// environment variables accessible via os.Getenv and os.LookupEnv. After they
+// are done, all changes to environment variables are reset.
+package climatecontrol
+
+import (
+	"os"
+	"strings"
+	"sync"
+)
+
+var mux = &sync.Mutex{}
+
+// WithEnv temporarily sets all given vars as environment variables during the
+// execution of f function. Existing environment variables are also available
+// within f. Any overridden environment variables will contain the overridden
+// value..
+//
+// After f execution completes all changes to environment variables are reset,
+// including manual changes within the f function.
+func WithEnv(vars map[string]string, f func()) {
+	mux.Lock()
+	defer mux.Unlock()
+
+	undo := parseEnviron(os.Environ())
+
+	apply(vars)
+	defer func() {
+		os.Clearenv()
+		apply(undo)
+	}()
+
+	f()
+}
+
+// WithCleanEnv temporarily changes all environment variables available within f
+// function to only be those provided. Existing environment variables are not
+// available within f.
+//
+// After f execution completes all changes to environment variables are reset,
+// including manual changes within the f function.
+func WithCleanEnv(vars map[string]string, f func()) {
+	mux.Lock()
+	defer mux.Unlock()
+
+	undo := parseEnviron(os.Environ())
+
+	os.Clearenv()
+	apply(vars)
+	defer func() {
+		os.Clearenv()
+		apply(undo)
+	}()
+
+	f()
+}
+
+func apply(vars map[string]string) {
+	for k, v := range vars {
+		os.Setenv(k, v)
+	}
+}
+
+func parseEnviron(vars []string) map[string]string {
+	r := map[string]string{}
+
+	for _, v := range vars {
+		i := strings.Index(v, "=")
+		if i < 1 {
+			continue
+		}
+
+		r[v[0:i]] = v[i+1:]
+	}
+
+	return r
+}

climatecontrol_example_test.go

@@ -0,0 +1,108 @@
+package climatecontrol_test
+
+import (
+	"fmt"
+	"os"
+
+	cc "github.com/jimeh/climatecontrol"
+)
+
+func ExampleWithEnv() {
+	// existing environment variables
+	os.Setenv("MYAPP_HOSTNAME", "myapp.com")
+	os.Setenv("MYAPP_PORT", "80")
+
+	fmt.Println("Before:")
+	fmt.Printf(" - MYAPP_HOSTNAME=%s\n", os.Getenv("MYAPP_HOSTNAME"))
+	fmt.Printf(" - MYAPP_PORT=%s\n", os.Getenv("MYAPP_PORT"))
+	fmt.Printf(" - MYAPP_THEME=%s\n", os.Getenv("MYAPP_THEME"))
+	fmt.Printf(" - MYAPP_TESTING=%s\n", os.Getenv("MYAPP_TESTING"))
+
+	// temporary environment variables
+	env := map[string]string{
+		"MYAPP_HOSTNAME": "testing-myapp.test",
+		"MYAPP_TESTING":  "unit",
+	}
+	cc.WithEnv(env, func() {
+		os.Setenv("MYAPP_THEME", "dark")
+
+		fmt.Println("Inside func:")
+		fmt.Printf(" - MYAPP_HOSTNAME=%s\n", os.Getenv("MYAPP_HOSTNAME"))
+		fmt.Printf(" - MYAPP_PORT=%s\n", os.Getenv("MYAPP_PORT"))
+		fmt.Printf(" - MYAPP_THEME=%s\n", os.Getenv("MYAPP_THEME"))
+		fmt.Printf(" - MYAPP_TESTING=%s\n", os.Getenv("MYAPP_TESTING"))
+	})
+
+	// original environment variables restored
+	fmt.Println("After:")
+	fmt.Printf(" - MYAPP_HOSTNAME=%s\n", os.Getenv("MYAPP_HOSTNAME"))
+	fmt.Printf(" - MYAPP_PORT=%s\n", os.Getenv("MYAPP_PORT"))
+	fmt.Printf(" - MYAPP_THEME=%s\n", os.Getenv("MYAPP_THEME"))
+	fmt.Printf(" - MYAPP_TESTING=%s\n", os.Getenv("MYAPP_TESTING"))
+	// Output:
+	// Before:
+	//  - MYAPP_HOSTNAME=myapp.com
+	//  - MYAPP_PORT=80
+	//  - MYAPP_THEME=
+	//  - MYAPP_TESTING=
+	// Inside func:
+	//  - MYAPP_HOSTNAME=testing-myapp.test
+	//  - MYAPP_PORT=80
+	//  - MYAPP_THEME=dark
+	//  - MYAPP_TESTING=unit
+	// After:
+	//  - MYAPP_HOSTNAME=myapp.com
+	//  - MYAPP_PORT=80
+	//  - MYAPP_THEME=
+	//  - MYAPP_TESTING=
+}
+
+func ExampleWithCleanEnv() {
+	// existing environment variables
+	os.Setenv("MYAPP_HOSTNAME", "myapp.com")
+	os.Setenv("MYAPP_PORT", "80")
+
+	fmt.Println("Before:")
+	fmt.Printf(" - MYAPP_HOSTNAME=%s\n", os.Getenv("MYAPP_HOSTNAME"))
+	fmt.Printf(" - MYAPP_PORT=%s\n", os.Getenv("MYAPP_PORT"))
+	fmt.Printf(" - MYAPP_THEME=%s\n", os.Getenv("MYAPP_THEME"))
+	fmt.Printf(" - MYAPP_TESTING=%s\n", os.Getenv("MYAPP_TESTING"))
+
+	// temporary environment variables
+	env := map[string]string{
+		"MYAPP_HOSTNAME": "testing-myapp.test",
+		"MYAPP_TESTING":  "unit",
+	}
+	cc.WithCleanEnv(env, func() {
+		os.Setenv("MYAPP_THEME", "dark")
+
+		fmt.Println("Inside func:")
+		fmt.Printf(" - MYAPP_HOSTNAME=%s\n", os.Getenv("MYAPP_HOSTNAME"))
+		fmt.Printf(" - MYAPP_PORT=%s\n", os.Getenv("MYAPP_PORT"))
+		fmt.Printf(" - MYAPP_THEME=%s\n", os.Getenv("MYAPP_THEME"))
+		fmt.Printf(" - MYAPP_TESTING=%s\n", os.Getenv("MYAPP_TESTING"))
+	})
+
+	// original environme
+	fmt.Println("After:")
+	fmt.Printf(" - MYAPP_HOSTNAME=%s\n", os.Getenv("MYAPP_HOSTNAME"))
+	fmt.Printf(" - MYAPP_PORT=%s\n", os.Getenv("MYAPP_PORT"))
+	fmt.Printf(" - MYAPP_THEME=%s\n", os.Getenv("MYAPP_THEME"))
+	fmt.Printf(" - MYAPP_TESTING=%s\n", os.Getenv("MYAPP_TESTING"))
+	// Output:
+	// Before:
+	//  - MYAPP_HOSTNAME=myapp.com
+	//  - MYAPP_PORT=80
+	//  - MYAPP_THEME=
+	//  - MYAPP_TESTING=
+	// Inside func:
+	//  - MYAPP_HOSTNAME=testing-myapp.test
+	//  - MYAPP_PORT=
+	//  - MYAPP_THEME=dark
+	//  - MYAPP_TESTING=unit
+	// After:
+	//  - MYAPP_HOSTNAME=myapp.com
+	//  - MYAPP_PORT=80
+	//  - MYAPP_THEME=
+	//  - MYAPP_TESTING=
+}

climatecontrol_test.go

@@ -0,0 +1,178 @@
+package climatecontrol
+
+import (
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestWithEnv(t *testing.T) {
+	tests := []struct {
+		name string
+		env  map[string]string
+	}{
+		{
+			name: "empty",
+			env:  map[string]string{},
+		},
+		{
+			name: "new vars",
+			env: map[string]string{
+				"CC_TEST_INSIDE": "new var is here",
+				"CC_TEST_FOO":    "bar",
+			},
+		},
+		{
+			name: "set existing",
+			env: map[string]string{
+				"CC_TEST_INSIDE":  "new var is here",
+				"CC_TEST_OUTSIDE": "this is not the same",
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			os.Setenv("CC_TEST_OUTSIDE", t.Name())
+			outside := parseEnviron(os.Environ())
+
+			WithEnv(tt.env, func() {
+				os.Setenv("CC_TEST_SET_INSIDE", t.Name()+"-manual")
+
+				for k, v := range tt.env {
+					got := os.Getenv(k)
+					assert.Equal(t, v, got)
+				}
+
+				for k, v := range outside {
+					if _, ok := tt.env[k]; !ok {
+						assert.Equal(t, v, os.Getenv(k))
+					}
+				}
+			})
+
+			_, exists := os.LookupEnv("CC_TEST_SET_INSIDE")
+			assert.Equal(t, false, exists)
+
+			for k := range tt.env {
+				if _, ok := outside[k]; !ok {
+					_, exists := os.LookupEnv(k)
+					assert.Equal(t, false, exists)
+				}
+			}
+
+			for k, v := range outside {
+				assert.Equal(t, v, os.Getenv(k))
+			}
+
+			os.Unsetenv("CC_TEST_OUTSIDE")
+		})
+	}
+}
+
+func TestWithCleanEnv(t *testing.T) {
+	tests := []struct {
+		name string
+		env  map[string]string
+	}{
+		{
+			name: "empty",
+			env:  map[string]string{},
+		},
+		{
+			name: "new vars",
+			env: map[string]string{
+				"CC_TEST_INSIDE": "new var is here",
+				"CC_TEST_FOO":    "bar",
+			},
+		},
+		{
+			name: "set existing",
+			env: map[string]string{
+				"CC_TEST_INSIDE":  "new var is here",
+				"CC_TEST_OUTSIDE": "is is not the same",
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			os.Setenv("CC_TEST_OUTSIDE", t.Name())
+			outside := parseEnviron(os.Environ())
+
+			WithCleanEnv(tt.env, func() {
+				os.Setenv("CC_TEST_SET_INSIDE", t.Name()+"-manual")
+
+				for k, v := range tt.env {
+					got := os.Getenv(k)
+					assert.Equal(t, v, got)
+				}
+
+				for k := range outside {
+					if _, ok := tt.env[k]; !ok {
+						_, exists := os.LookupEnv(k)
+						assert.Equal(t, false, exists)
+					}
+				}
+			})
+
+			_, exists := os.LookupEnv("CC_TEST_SET_INSIDE")
+			assert.Equal(t, false, exists)
+
+			for k := range tt.env {
+				if _, ok := outside[k]; !ok {
+					_, exists := os.LookupEnv(k)
+					assert.Equal(t, false, exists)
+				}
+			}
+
+			for k, v := range outside {
+				assert.Equal(t, v, os.Getenv(k))
+			}
+
+			os.Unsetenv("CC_TEST_OUTSIDE")
+		})
+	}
+}
+
+func Test_parseEnviron(t *testing.T) {
+	tests := []struct {
+		name string
+		vars []string
+		want map[string]string
+	}{
+		{
+			name: "empty",
+			vars: []string{},
+			want: map[string]string{},
+		},
+		{
+			name: "various",
+			vars: []string{
+				"USER=john",
+				"NAME=John Doe",
+				"SHELL=/bin/bash",
+				"GOPRIVATE=",
+				"X=11",
+				"TAGS=foo=bar,hello=world",
+				"_=go",
+				"INVALID-var",
+			},
+			want: map[string]string{
+				"USER":      "john",
+				"NAME":      "John Doe",
+				"SHELL":     "/bin/bash",
+				"GOPRIVATE": "",
+				"X":         "11",
+				"TAGS":      "foo=bar,hello=world",
+				"_":         "go",
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := parseEnviron(tt.vars)
+
+			assert.Equal(t, tt.want, got)
+		})
+	}
+}

go.mod

@@ -0,0 +1,5 @@
+module github.com/jimeh/climatecontrol
+
+go 1.15
+
+require github.com/stretchr/testify v1.6.1

go.sum

@@ -0,0 +1,10 @@
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/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/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
+github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=