libs/common: remove unused functions (#3784)

- The removed functions are not used in Iavl, Cosmos-sdk and tendermint repos
- Code-hygenie `whoop whoop`

Signed-off-by: Marko Baricevic <marbar3778@yahoo.com>

CHANGELOG_PENDING.md

@@ -22,6 +22,7 @@ program](https://hackerone.com/tendermint).
     not.
   - [libs] Remove unused `db/debugDB` and `common/colors.go` & `errors/errors.go` files (@marbar3778)
   - [libs] \#2432 Remove unused `common/heap.go` file (@marbar3778)
+  - [libs] Remove unused `date.go`, `io.go`. Remove `GoPath()`, `Prompt()` and `IsDirEmpty()` functions from `os.go` (@marbar3778)
 
 - Blockchain Protocol
 

libs/common/date.go

@@ -1,43 +0,0 @@
-package common
-
-import (
-	"strings"
-	"time"
-
-	"github.com/pkg/errors"
-)
-
-// TimeLayout helps to parse a date string of the format YYYY-MM-DD
-//   Intended to be used with the following function:
-// 	 time.Parse(TimeLayout, date)
-var TimeLayout = "2006-01-02" //this represents YYYY-MM-DD
-
-// ParseDateRange parses a date range string of the format start:end
-//   where the start and end date are of the format YYYY-MM-DD.
-//   The parsed dates are time.Time and will return the zero time for
-//   unbounded dates, ex:
-//   unbounded start:	:2000-12-31
-//	 unbounded end: 	2000-12-31:
-func ParseDateRange(dateRange string) (startDate, endDate time.Time, err error) {
-	dates := strings.Split(dateRange, ":")
-	if len(dates) != 2 {
-		err = errors.New("bad date range, must be in format date:date")
-		return
-	}
-	parseDate := func(date string) (out time.Time, err error) {
-		if len(date) == 0 {
-			return
-		}
-		out, err = time.Parse(TimeLayout, date)
-		return
-	}
-	startDate, err = parseDate(dates[0])
-	if err != nil {
-		return
-	}
-	endDate, err = parseDate(dates[1])
-	if err != nil {
-		return
-	}
-	return
-}

libs/common/date_test.go

@@ -1,46 +0,0 @@
-package common
-
-import (
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-)
-
-var (
-	date  = time.Date(2015, time.Month(12), 31, 0, 0, 0, 0, time.UTC)
-	date2 = time.Date(2016, time.Month(12), 31, 0, 0, 0, 0, time.UTC)
-	zero  time.Time
-)
-
-func TestParseDateRange(t *testing.T) {
-	assert := assert.New(t)
-
-	var testDates = []struct {
-		dateStr string
-		start   time.Time
-		end     time.Time
-		errNil  bool
-	}{
-		{"2015-12-31:2016-12-31", date, date2, true},
-		{"2015-12-31:", date, zero, true},
-		{":2016-12-31", zero, date2, true},
-		{"2016-12-31", zero, zero, false},
-		{"2016-31-12:", zero, zero, false},
-		{":2016-31-12", zero, zero, false},
-	}
-
-	for _, test := range testDates {
-		start, end, err := ParseDateRange(test.dateStr)
-		if test.errNil {
-			assert.Nil(err)
-			testPtr := func(want, have time.Time) {
-				assert.True(have.Equal(want))
-			}
-			testPtr(test.start, start)
-			testPtr(test.end, end)
-		} else {
-			assert.NotNil(err)
-		}
-	}
-}

libs/common/io.go

@@ -1,74 +0,0 @@
-package common
-
-import (
-	"bytes"
-	"errors"
-	"io"
-)
-
-type PrefixedReader struct {
-	Prefix []byte
-	reader io.Reader
-}
-
-func NewPrefixedReader(prefix []byte, reader io.Reader) *PrefixedReader {
-	return &PrefixedReader{prefix, reader}
-}
-
-func (pr *PrefixedReader) Read(p []byte) (n int, err error) {
-	if len(pr.Prefix) > 0 {
-		read := copy(p, pr.Prefix)
-		pr.Prefix = pr.Prefix[read:]
-		return read, nil
-	}
-	return pr.reader.Read(p)
-}
-
-// NOTE: Not goroutine safe
-type BufferCloser struct {
-	bytes.Buffer
-	Closed bool
-}
-
-func NewBufferCloser(buf []byte) *BufferCloser {
-	return &BufferCloser{
-		*bytes.NewBuffer(buf),
-		false,
-	}
-}
-
-func (bc *BufferCloser) Close() error {
-	if bc.Closed {
-		return errors.New("BufferCloser already closed")
-	}
-	bc.Closed = true
-	return nil
-}
-
-func (bc *BufferCloser) Write(p []byte) (n int, err error) {
-	if bc.Closed {
-		return 0, errors.New("Cannot write to closed BufferCloser")
-	}
-	return bc.Buffer.Write(p)
-}
-
-func (bc *BufferCloser) WriteByte(c byte) error {
-	if bc.Closed {
-		return errors.New("Cannot write to closed BufferCloser")
-	}
-	return bc.Buffer.WriteByte(c)
-}
-
-func (bc *BufferCloser) WriteRune(r rune) (n int, err error) {
-	if bc.Closed {
-		return 0, errors.New("Cannot write to closed BufferCloser")
-	}
-	return bc.Buffer.WriteRune(r)
-}
-
-func (bc *BufferCloser) WriteString(s string) (n int, err error) {
-	if bc.Closed {
-		return 0, errors.New("Cannot write to closed BufferCloser")
-	}
-	return bc.Buffer.WriteString(s)
-}

libs/common/os.go

@@ -1,39 +1,13 @@
 package common
 
 import (
-	"bufio"
 	"fmt"
-	"io"
 	"io/ioutil"
 	"os"
-	"os/exec"
 	"os/signal"
-	"strings"
 	"syscall"
 )
 
-var gopath string
-
-// GoPath returns GOPATH env variable value. If it is not set, this function
-// will try to call `go env GOPATH` subcommand.
-func GoPath() string {
-	if gopath != "" {
-		return gopath
-	}
-
-	path := os.Getenv("GOPATH")
-	if len(path) == 0 {
-		goCmd := exec.Command("go", "env", "GOPATH")
-		out, err := goCmd.Output()
-		if err != nil {
-			panic(fmt.Sprintf("failed to determine gopath: %v", err))
-		}
-		path = string(out)
-	}
-	gopath = path
-	return path
-}
-
 type logger interface {
 	Info(msg string, keyvals ...interface{})
 }
@@ -78,25 +52,6 @@ func EnsureDir(dir string, mode os.FileMode) error {
 	return nil
 }
 
-func IsDirEmpty(name string) (bool, error) {
-	f, err := os.Open(name)
-	if err != nil {
-		if os.IsNotExist(err) {
-			return true, err
-		}
-		// Otherwise perhaps a permission
-		// error or some other error.
-		return false, err
-	}
-	defer f.Close()
-
-	_, err = f.Readdirnames(1) // Or f.Readdir(1)
-	if err == io.EOF {
-		return true, nil
-	}
-	return false, err // Either not empty or error, suits both cases
-}
-
 func FileExists(filePath string) bool {
 	_, err := os.Stat(filePath)
 	return !os.IsNotExist(err)
@@ -125,19 +80,3 @@ func MustWriteFile(filePath string, contents []byte, mode os.FileMode) {
 		Exit(fmt.Sprintf("MustWriteFile failed: %v", err))
 	}
 }
-
-//--------------------------------------------------------------------------------
-
-func Prompt(prompt string, defaultValue string) (string, error) {
-	fmt.Print(prompt)
-	reader := bufio.NewReader(os.Stdin)
-	line, err := reader.ReadString('\n')
-	if err != nil {
-		return defaultValue, err
-	}
-	line = strings.TrimSpace(line)
-	if line == "" {
-		return defaultValue, nil
-	}
-	return line, nil
-}

libs/common/os_test.go

@@ -1,46 +0,0 @@
-package common
-
-import (
-	"os"
-	"testing"
-)
-
-func TestOSGoPath(t *testing.T) {
-	// restore original gopath upon exit
-	path := os.Getenv("GOPATH")
-	defer func() {
-		_ = os.Setenv("GOPATH", path)
-	}()
-
-	err := os.Setenv("GOPATH", "~/testgopath")
-	if err != nil {
-		t.Fatal(err)
-	}
-	path = GoPath()
-	if path != "~/testgopath" {
-		t.Fatalf("should get GOPATH env var value, got %v", path)
-	}
-	os.Unsetenv("GOPATH")
-
-	path = GoPath()
-	if path != "~/testgopath" {
-		t.Fatalf("subsequent calls should return the same value, got %v", path)
-	}
-}
-
-func TestOSGoPathWithoutEnvVar(t *testing.T) {
-	// restore original gopath upon exit
-	path := os.Getenv("GOPATH")
-	defer func() {
-		_ = os.Setenv("GOPATH", path)
-	}()
-
-	os.Unsetenv("GOPATH")
-	// reset cache
-	gopath = ""
-
-	path = GoPath()
-	if path == "" || path == "~/testgopath" {
-		t.Fatalf("should get nonempty result of calling go env GOPATH, got %v", path)
-	}
-}