feat: Add support of uint8 (#78)

* chore: Add helper for generating readme doc

* feat: Add support of uint8

Author: obalunenko

.gitignore

@@ -19,4 +19,5 @@ bin/
 dist/
 coverage/
 .DS_Store
-tests-report.json
+tests-report.json
+README_doc.md

Makefile

@@ -54,6 +54,11 @@ update-readme-cover: prepare-cover-report
 	$(COMPOSE_TOOLS_CMD_UP) update-readme-coverage update-readme-coverage
 .PHONY: update-readme-cover
 
+## Update readme doc.
+update-readme-doc:
+	$(COMPOSE_TOOLS_CMD_UP) update-readme-doc update-readme-doc
+.PHONY: update-readme-doc
+
 ## Run tests.
 test:
 	$(COMPOSE_TOOLS_CMD_UP) run-tests run-tests

README.md

@@ -10,8 +10,6 @@
 Package getenv provides functionality for loading environment variables and parse them into go builtin types.
 
 Types supported:
-
-```text
 - string
 - []string
 - int
@@ -24,6 +22,7 @@ Types supported:
 - []int32
 - int64
 - []int64
+- uint8
 - uint64
 - []uint64
 - uint
@@ -37,7 +36,6 @@ Types supported:
 - []time.Time
 - time.Duration
 - bool
-```
 
 ## Examples
 
@@ -119,7 +117,7 @@ func main() {
 
 ```
 
- Output:
+Output:
 
 ```
 [string]: golly

deployments/docker-compose/go-tools-docker-compose.yml

@@ -37,6 +37,11 @@ services:
       service: tools
     entrypoint: /bin/sh -c './scripts/update-readme-coverage.sh'
 
+  update-readme-doc:
+    extends:
+      service: tools
+    entrypoint: /bin/sh -c './scripts/update-readme-doc.sh'
+
   lint-full:
     extends:
       service: tools

getenv.go

@@ -13,6 +13,7 @@
 // - []int32
 // - int64
 // - []int64
+// - uint8
 // - uint64
 // - []uint64
 // - uint

getenv_test.go

@@ -1358,6 +1358,82 @@ func TestDurationOrDefault(t *testing.T) {
 	}
 }
 
+func TestUint8OrDefault(t *testing.T) {
+	type args struct {
+		key        string
+		defaultVal uint8
+	}
+
+	type expected struct {
+		val uint8
+	}
+
+	var tests = []struct {
+		name     string
+		precond  precondition
+		args     args
+		expected expected
+	}{
+		{
+			name: "env not set - default returned",
+			precond: precondition{
+				setenv: setenv{
+					isSet: false,
+					val:   "12",
+				},
+			},
+			args: args{
+				key:        testEnvKey,
+				defaultVal: 99,
+			},
+			expected: expected{
+				val: 99,
+			},
+		},
+		{
+			name: "env set - env value returned",
+			precond: precondition{
+				setenv: setenv{
+					isSet: true,
+					val:   "12",
+				},
+			},
+			args: args{
+				key:        testEnvKey,
+				defaultVal: 99,
+			},
+			expected: expected{
+				val: 12,
+			},
+		},
+		{
+			name: "empty env value set - default returned",
+			precond: precondition{
+				setenv: setenv{
+					isSet: true,
+					val:   "",
+				},
+			},
+			args: args{
+				key:        testEnvKey,
+				defaultVal: 99,
+			},
+			expected: expected{
+				val: 99,
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			tt.precond.maybeSetEnv(t, tt.args.key)
+
+			got := getenv.EnvOrDefault(tt.args.key, tt.args.defaultVal)
+			assert.Equal(t, tt.expected.val, got)
+		})
+	}
+}
+
 func TestUint64OrDefault(t *testing.T) {
 	type args struct {
 		key        string

internal/constraint.go

@@ -22,7 +22,7 @@ type (
 
 	// Uint is a constraint for unsigned integer and slice of unsigned integers.
 	Uint interface {
-		uint64 | []uint64 | uint | []uint | []uint32 | uint32
+		uint | []uint | uint8 | uint32 | []uint32 | uint64 | []uint64
 	}
 
 	// Float is a constraint for floats and slice of floats.

internal/iface.go

@@ -15,7 +15,7 @@ func NewEnvParser(v any) EnvParser {
 		p = newStringParser(t)
 	case int, []int, int8, []int8, int16, []int16, int32, []int32, int64, []int64:
 		p = newIntParser(t)
-	case uint64, []uint64, uint, []uint, uint32, []uint32:
+	case uint, []uint, uint8, uint32, []uint32, uint64, []uint64:
 		p = newUintParser(t)
 	case bool:
 		p = boolParser(t)
@@ -78,18 +78,20 @@ func newIntParser(v any) EnvParser {
 
 func newUintParser(v any) EnvParser {
 	switch t := v.(type) {
-	case uint64:
-		return uint64Parser(t)
-	case []uint64:
-		return uint64SliceParser(t)
+	case uint8:
+		return uint8Parser(t)
 	case uint:
 		return uintParser(t)
 	case []uint:
 		return uintSliceParser(t)
-	case []uint32:
-		return uint32SliceParser(t)
 	case uint32:
 		return uint32Parser(t)
+	case []uint32:
+		return uint32SliceParser(t)
+	case uint64:
+		return uint64Parser(t)
+	case []uint64:
+		return uint64SliceParser(t)
 	default:
 		return nil
 	}
@@ -302,6 +304,14 @@ func (i uint64SliceParser) ParseEnv(key string, defaltVal any, options Parameter
 	return val
 }
 
+type uint8Parser uint
+
+func (d uint8Parser) ParseEnv(key string, defaltVal any, _ Parameters) any {
+	val := uint8OrDefault(key, defaltVal.(uint8))
+
+	return val
+}
+
 type uintParser uint
 
 func (d uintParser) ParseEnv(key string, defaltVal any, _ Parameters) any {

internal/iface_test.go

@@ -7,6 +7,10 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
+type notsupported struct {
+	name string
+}
+
 func TestNewEnvParser(t *testing.T) {
 	type args struct {
 		v any
@@ -83,7 +87,15 @@ func TestNewEnvParser(t *testing.T) {
 			wantPanic: assert.NotPanics,
 		},
 		{
-			name: "uint23",
+			name: "uint8",
+			args: args{
+				v: uint8(1),
+			},
+			want:      uint8Parser(1),
+			wantPanic: assert.NotPanics,
+		},
+		{
+			name: "uint32",
 			args: args{
 				v: uint32(1),
 			},
@@ -221,7 +233,9 @@ func TestNewEnvParser(t *testing.T) {
 		{
 			name: "not supported - panics",
 			args: args{
-				v: byte(1),
+				v: notsupported{
+					name: "name",
+				},
 			},
 			want:      nil,
 			wantPanic: assert.Panics,
@@ -359,6 +373,25 @@ func Test_ParseEnv(t *testing.T) {
 			},
 			want: []float64{-1.2, 0.2},
 		},
+		{
+			name: "uint8Parser",
+			s:    uint8Parser(0),
+			precond: precondition{
+				setenv: setenv{
+					isSet: true,
+					val:   "12",
+				},
+			},
+			args: args{
+				key:       testEnvKey,
+				defaltVal: uint8(99),
+				in2: Parameters{
+					Separator: ",",
+					Layout:    "",
+				},
+			},
+			want: uint8(12),
+		},
 		{
 			name: "uint64Parser",
 			s:    uint64Parser(0),

internal/parsers.go

@@ -470,7 +470,29 @@ func uint64SliceOrDefault(key string, defaultVal []uint64, sep string) []uint64
 	return val
 }
 
-// uintOrDefault retrieves the unt64 value of the environment variable named
+// uint8OrDefault retrieves the unt8 value of the environment variable named
+// by the key.
+// If variable not set or value is empty - defaultVal will be returned.
+func uint8OrDefault(key string, defaultVal uint8) uint8 {
+	env := stringOrDefault(key, "")
+	if env == "" {
+		return defaultVal
+	}
+
+	const (
+		base    = 10
+		bitsize = 8
+	)
+
+	val, err := strconv.ParseUint(env, base, bitsize)
+	if err != nil {
+		return defaultVal
+	}
+
+	return uint8(val)
+}
+
+// uintOrDefault retrieves the unt value of the environment variable named
 // by the key.
 // If variable not set or value is empty - defaultVal will be returned.
 func uintOrDefault(key string, defaultVal uint) uint {