[#200] add vcs.factory package

src/engine/tcr.go

@@ -23,7 +23,6 @@ SOFTWARE.
 package engine
 
 import (
-	"fmt"
 	"github.com/murex/tcr/checker"
 	"github.com/murex/tcr/events"
 	"github.com/murex/tcr/filesystem"
@@ -39,8 +38,7 @@ import (
 	"github.com/murex/tcr/toolchain"
 	"github.com/murex/tcr/ui"
 	"github.com/murex/tcr/vcs"
-	"github.com/murex/tcr/vcs/git"
-	"github.com/murex/tcr/vcs/p4"
+	"github.com/murex/tcr/vcs/factory"
 	"gopkg.in/tomb.v2"
 	"os"
 	"strings"
@@ -249,18 +247,14 @@ func (tcr *TCREngine) initVCS(vcsName string) {
 	if tcr.vcs != nil {
 		return // VCS should be initialized only once
 	}
-
 	var err error
-	switch strings.ToLower(vcsName) {
-	case git.Name:
-		tcr.vcs, err = git.New(tcr.sourceTree.GetBaseDir())
-	case p4.Name:
-		tcr.vcs, err = p4.New(tcr.sourceTree.GetBaseDir())
+	tcr.vcs, err = factory.InitVCS(vcsName, tcr.sourceTree.GetBaseDir())
+	switch err.(type) {
+	case *factory.UnsupportedVCSError:
+		tcr.handleError(err, true, status.ConfigError)
 	default:
-		tcr.handleError(fmt.Errorf("VCS not supported: %s", vcsName), true, status.ConfigError)
-		return
+		tcr.handleError(err, true, status.VCSError)
 	}
-	tcr.handleError(err, true, status.VCSError)
 }
 
 func (tcr *TCREngine) initSourceTree(p params.Params) {

src/vcs/factory/vcs_factory.go

@@ -0,0 +1,53 @@
+/*
+Copyright (c) 2023 Murex
+
+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.
+*/
+
+package factory
+
+import (
+	"fmt"
+	"github.com/murex/tcr/vcs"
+	"github.com/murex/tcr/vcs/git"
+	"github.com/murex/tcr/vcs/p4"
+	"strings"
+)
+
+// UnsupportedVCSError is returned when the provided VCS name is not supported by the factory.
+type UnsupportedVCSError struct {
+	vcsName string
+}
+
+// Error returns the error description
+func (e *UnsupportedVCSError) Error() string {
+	return fmt.Sprintf("VCS not supported: \"%s\"", e.vcsName)
+}
+
+// InitVCS returns the VCS instance of type defined by name, working on the provided directory
+func InitVCS(name string, dir string) (vcs.Interface, error) {
+	switch strings.ToLower(name) {
+	case git.Name:
+		return git.New(dir)
+	case p4.Name:
+		return p4.New(dir)
+	default:
+		return nil, &UnsupportedVCSError{name}
+	}
+}

src/vcs/factory/vcs_factory_test.go

@@ -0,0 +1,50 @@
+/*
+Copyright (c) 2023 Murex
+
+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.
+*/
+
+package factory
+
+import (
+	"github.com/stretchr/testify/assert"
+	"reflect"
+	"testing"
+)
+
+func Test_vcs_factory_returns_an_error_when_vcs_is_not_supported(t *testing.T) {
+	v, err := InitVCS("unknown-vcs", "")
+	assert.IsType(t, &UnsupportedVCSError{}, err)
+	assert.Zero(t, v)
+}
+
+func Test_unsupported_vcs_message_format(t *testing.T) {
+	err := UnsupportedVCSError{"some-vcs"}
+	assert.Equal(t, "VCS not supported: \"some-vcs\"", err.Error())
+}
+
+func Test_vcs_factory_supports_git(t *testing.T) {
+	_, err := InitVCS("git", "")
+	assert.NotEqual(t, reflect.TypeOf(&UnsupportedVCSError{}), reflect.TypeOf(err))
+}
+
+func Test_vcs_factory_supports_p4(t *testing.T) {
+	_, err := InitVCS("p4", "")
+	assert.NotEqual(t, reflect.TypeOf(&UnsupportedVCSError{}), reflect.TypeOf(err))
+}