enhance doc

pkg/build/build.go

@@ -110,7 +110,7 @@ func (b *Build) Build() error {
 // the binary name is always same as the directory name of current directory
 func (b *Build) determineOutputDir(outputDir string) (string, error) {
 	if b.TmpDir == "" {
-		return "", fmt.Errorf("can only be called after Build.MvProjectsToTmp(): %w", ErrWrongCallSequence)
+		return "", fmt.Errorf("can only be called after Build.MvProjectsToTmp(): %w", ErrEmptyTempWorkingDir)
 	}
 
 	// fix #43

pkg/build/build_test.go

@@ -70,7 +70,7 @@ func TestCheckParameters(t *testing.T) {
 func TestDetermineOutputDir(t *testing.T) {
 	b := &Build{}
 	_, err := b.determineOutputDir("")
-	assert.Equal(t, errors.Is(err, ErrWrongCallSequence), true, "called before Build.MvProjectsToTmp() should fail")
+	assert.Equal(t, errors.Is(err, ErrEmptyTempWorkingDir), true, "called before Build.MvProjectsToTmp() should fail")
 
 	b.TmpDir = "fake"
 	_, err = b.determineOutputDir("xx")

pkg/build/errors.go

@@ -5,12 +5,20 @@ import (
 )
 
 var (
-	ErrShouldNotReached           = errors.New("should never be reached")
+	// ErrShouldNotReached represents the logic should not be reached in normal flow
-	ErrGocShouldExecInProject     = errors.New("goc not executed in project directory")
+	ErrShouldNotReached = errors.New("should never be reached")
+	// ErrGocShouldExecInProject represents goc currently not support for the project
+	ErrGocShouldExecInProject = errors.New("goc not support for such project directory")
+	// ErrWrongPackageTypeForInstall represents goc install command only support limited arguments
 	ErrWrongPackageTypeForInstall = errors.New("packages only support \".\" and \"./...\"")
-	ErrWrongPackageTypeForBuild   = errors.New("packages only support \".\"")
+	// ErrWrongPackageTypeForBuild represents goc build command only support limited arguments
-	ErrTooManyArgs                = errors.New("too many args")
+	ErrWrongPackageTypeForBuild = errors.New("packages only support \".\"")
-	ErrInvalidWorkingDir          = errors.New("the working directory is invalid")
+	// ErrTooManyArgs represents goc CLI only support limited arguments
-	ErrWrongCallSequence          = errors.New("function should be called in a specified sequence")
+	ErrTooManyArgs = errors.New("too many args")
-	ErrNoplaceToInstall           = errors.New("dont know where to install")
+	// ErrInvalidWorkingDir represents the working directory is invalid
+	ErrInvalidWorkingDir = errors.New("the working directory is invalid")
+	// ErrEmptyTempWorkingDir represent the error that temporary working directory is empty
+	ErrEmptyTempWorkingDir = errors.New("temporary working directory is empty")
+	// ErrNoPlaceToInstall represents the err that no place to install the generated binary
+	ErrNoPlaceToInstall = errors.New("don't know where to install")
 )

pkg/build/tmpfolder.go

@@ -172,7 +172,7 @@ func (b *Build) findWhereToInstall() (string, error) {
 
 	if false == b.IsMod {
 		if b.Root == "" {
-			return "", ErrNoplaceToInstall
+			return "", ErrNoPlaceToInstall
 		}
 		return filepath.Join(b.Root, "bin"), nil
 	}

pkg/build/tmpfolder_test.go

@@ -133,7 +133,7 @@ func TestFindWhereToInstall(t *testing.T) {
 		Root:  "",
 	}
 	_, err := b.findWhereToInstall()
-	assert.EqualError(t, err, ErrNoplaceToInstall.Error())
+	assert.EqualError(t, err, ErrNoPlaceToInstall.Error())
 
 	// if $GOBIN not found
 	// and if $GOPATH not found