Merge pull request #177 from A-Hilaly/git-version

Check git version in repo RmConfigs

2 files changed, 84 insertions, 9 deletions

diff --git a/repository/git.go b/repository/git.go
index c8c45d6a..9ec7905a 100644
--- a/repository/git.go
+++ b/repository/git.go
@@ -3,7 +3,6 @@ package repository
 
 import (
 	"bytes"
-	"errors"
 	"fmt"
 	"io"
 	"os/exec"
@@ -11,6 +10,9 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/blang/semver"
+	"github.com/pkg/errors"
+
 	"github.com/MichaelMure/git-bug/util/git"
 	"github.com/MichaelMure/git-bug/util/lamport"
 )
@@ -259,16 +261,89 @@ func (repo *GitRepo) ReadConfigString(key string) (string, error) {
 	return lines[0], nil
 }
 
+func (repo *GitRepo) rmSection(keyPrefix string) error {
+	_, err := repo.runGitCommand("config", "--remove-section", keyPrefix)
+	return err
+}
+
+func (repo *GitRepo) unsetAll(keyPrefix string) error {
+	_, err := repo.runGitCommand("config", "--unset-all", keyPrefix)
+	return err
+}
+
+// return keyPrefix section
+// example: sectionFromKey(a.b.c.d) return a.b.c
+func sectionFromKey(keyPrefix string) string {
+	s := strings.Split(keyPrefix, ".")
+	if len(s) == 1 {
+		return keyPrefix
+	}
+
+	return strings.Join(s[:len(s)-1], ".")
+}
+
+// rmConfigs with git version lesser than 2.18
+func (repo *GitRepo) rmConfigsGitVersionLT218(keyPrefix string) error {
+	// try to remove key/value pair by key
+	err := repo.unsetAll(keyPrefix)
+	if err != nil {
+		return repo.rmSection(keyPrefix)
+	}
+
+	m, err := repo.ReadConfigs(sectionFromKey(keyPrefix))
+	if err != nil {
+		return err
+	}
+
+	// if section doesn't have any left key/value remove the section
+	if len(m) == 0 {
+		return repo.rmSection(sectionFromKey(keyPrefix))
+	}
+
+	return nil
+}
+
 // RmConfigs remove all key/value pair matching the key prefix
 func (repo *GitRepo) RmConfigs(keyPrefix string) error {
-	// try to remove key/value pair by key
-	_, err := repo.runGitCommand("config", "--unset-all", keyPrefix)
+	// starting from git 2.18.0 sections are automatically deleted when the last existing
+	// key/value is removed. Before 2.18.0 we should remove the section
+	// see https://github.com/git/git/blob/master/Documentation/RelNotes/2.18.0.txt#L379
+	lt218, err := repo.gitVersionLT218()
 	if err != nil {
-		// try to remove section
-		_, err = repo.runGitCommand("config", "--remove-section", keyPrefix)
+		return errors.Wrap(err, "getting git version")
 	}
 
-	return err
+	if lt218 {
+		return repo.rmConfigsGitVersionLT218(keyPrefix)
+	}
+
+	err = repo.unsetAll(keyPrefix)
+	if err != nil {
+		return repo.rmSection(keyPrefix)
+	}
+
+	return nil
+}
+
+func (repo *GitRepo) gitVersionLT218() (bool, error) {
+	versionOut, err := repo.runGitCommand("version")
+	if err != nil {
+		return false, err
+	}
+
+	versionString := strings.Fields(versionOut)[2]
+	version, err := semver.Make(versionString)
+	if err != nil {
+		return false, err
+	}
+
+	version218string := "2.18.0"
+	gitVersion218, err := semver.Make(version218string)
+	if err != nil {
+		return false, err
+	}
+
+	return version.LT(gitVersion218), nil
 }
 
 // FetchRefs fetch git refs from a remote
@@ -428,7 +503,7 @@ func (repo *GitRepo) FindCommonAncestor(hash1 git.Hash, hash2 git.Hash) (git.Has
 	stdout, err := repo.runGitCommand("merge-base", string(hash1), string(hash2))
 
 	if err != nil {
-		return "", nil
+		return "", err
 	}
 
 	return git.Hash(stdout), nil
@@ -439,7 +514,7 @@ func (repo *GitRepo) GetTreeHash(commit git.Hash) (git.Hash, error) {
 	stdout, err := repo.runGitCommand("rev-parse", string(commit)+"^{tree}")
 
 	if err != nil {
-		return "", nil
+		return "", err
 	}
 
 	return git.Hash(stdout), nil
diff --git a/repository/git_test.go b/repository/git_test.go
index 8bd3aa8e..20bf6ec3 100644
--- a/repository/git_test.go
+++ b/repository/git_test.go
@@ -55,7 +55,7 @@ func TestConfig(t *testing.T) {
 	assert.Error(t, err)
 
 	err = repo.RmConfigs("section")
-	assert.NoError(t, err)
+	assert.Error(t, err)
 
 	_, err = repo.ReadConfigString("section.key")
 	assert.Error(t, err)