4 files changed, 100 insertions, 7 deletions

diff --git a/plumbing/format/config/encoder.go b/plumbing/format/config/encoder.go
index 4eac896..de069ae 100644
--- a/plumbing/format/config/encoder.go
+++ b/plumbing/format/config/encoder.go
@@ -11,6 +11,10 @@ type Encoder struct {
 	w io.Writer
 }
 
+var (
+	subsectionReplacer = strings.NewReplacer(`"`, `\"`, `\`, `\\`)
+	valueReplacer = strings.NewReplacer(`"`, `\"`, `\`, `\\`, "\n", `\n`, "\t", `\t`, "\b", `\b`)
+)
 // NewEncoder returns a new encoder that writes to w.
 func NewEncoder(w io.Writer) *Encoder {
 	return &Encoder{w}
@@ -48,8 +52,7 @@ func (e *Encoder) encodeSection(s *Section) error {
 }
 
 func (e *Encoder) encodeSubsection(sectionName string, s *Subsection) error {
-	//TODO: escape
-	if err := e.printf("[%s \"%s\"]\n", sectionName, s.Name); err != nil {
+	if err := e.printf("[%s \"%s\"]\n", sectionName, subsectionReplacer.Replace(s.Name)); err != nil {
 		return err
 	}
 
@@ -58,12 +61,14 @@ func (e *Encoder) encodeSubsection(sectionName string, s *Subsection) error {
 
 func (e *Encoder) encodeOptions(opts Options) error {
 	for _, o := range opts {
-		pattern := "\t%s = %s\n"
-		if strings.Contains(o.Value, "\\") {
-			pattern = "\t%s = %q\n"
+		var value string
+		if strings.ContainsAny(o.Value, "#;\"\t\n\\") || strings.HasPrefix(o.Value, " ") || strings.HasSuffix(o.Value, " ") {
+			value = `"`+valueReplacer.Replace(o.Value)+`"`
+		} else {
+			value = o.Value
 		}
 
-		if err := e.printf(pattern, o.Key, o.Value); err != nil {
+		if err := e.printf("\t%s = %s\n", o.Key, value); err != nil {
 			return err
 		}
 	}
diff --git a/plumbing/format/config/fixtures_test.go b/plumbing/format/config/fixtures_test.go
index f3533df..2fa7840 100644
--- a/plumbing/format/config/fixtures_test.go
+++ b/plumbing/format/config/fixtures_test.go
@@ -43,6 +43,41 @@ var fixtures = []*Fixture{
 		Config: New().AddOption("core", "", "repositoryformatversion", "0"),
 	},
 	{
+		Raw: `[section]
+	option1 = "has # hash"
+	option2 = "has \" quote"
+	option3 = "has \\ backslash"
+	option4 = "has ; semicolon"
+	option5 = "has \n line-feed"
+	option6 = "has \t tab"
+	option7 = "  has leading spaces"
+	option8 = "has trailing spaces  "
+	option9 = has no special characters
+	option10 = has unusual ` + "\x01\x7f\xc8\x80 characters\n",
+		Text: `[section]
+	option1 = "has # hash"
+	option2 = "has \" quote"
+	option3 = "has \\ backslash"
+	option4 = "has ; semicolon"
+	option5 = "has \n line-feed"
+	option6 = "has \t tab"
+	option7 = "  has leading spaces"
+	option8 = "has trailing spaces  "
+	option9 = has no special characters
+	option10 = has unusual ` + "\x01\x7f\xc8\x80 characters\n",
+		Config: New().
+			AddOption("section", "", "option1", `has # hash`).
+			AddOption("section", "", "option2", `has " quote`).
+			AddOption("section", "", "option3", `has \ backslash`).
+			AddOption("section", "", "option4", `has ; semicolon`).
+			AddOption("section", "", "option5", "has \n line-feed").
+			AddOption("section", "", "option6", "has \t tab").
+			AddOption("section", "", "option7", `  has leading spaces`).
+			AddOption("section", "", "option8", `has trailing spaces  `).
+			AddOption("section", "", "option9", `has no special characters`).
+			AddOption("section", "", "option10", "has unusual \x01\x7f\u0200 characters"),
+	},
+	{
 		Raw: `
 			[sect1]
 			opt1 = value1
diff --git a/plumbing/format/config/format.go b/plumbing/format/config/format.go
new file mode 100644
index 0000000..4873ea9
--- /dev/null
+++ b/plumbing/format/config/format.go
@@ -0,0 +1,53 @@
+package config
+
+// RepositoryFormatVersion represents the repository format version,
+// as per defined at:
+//
+//	https://git-scm.com/docs/repository-version
+type RepositoryFormatVersion string
+
+const (
+	// Version_0 is the format defined by the initial version of git,
+	// including but not limited to the format of the repository
+	// directory, the repository configuration file, and the object
+	// and ref storage.
+	//
+	// Specifying the complete behavior of git is beyond the scope
+	// of this document.
+	Version_0 = "0"
+
+	// Version_1 is identical to version 0, with the following exceptions:
+	//
+	//   1. When reading the core.repositoryformatversion variable, a git
+	//		implementation which supports version 1 MUST also read any
+	//		configuration keys found in the extensions section of the
+	//		configuration file.
+	//
+	//	 2. If a version-1 repository specifies any extensions.* keys that
+	//		the running git has not implemented, the operation MUST NOT proceed.
+	//		Similarly, if the value of any known key is not understood by the
+	//		implementation, the operation MUST NOT proceed.
+	//
+	// Note that if no extensions are specified in the config file, then
+	// core.repositoryformatversion SHOULD be set to 0 (setting it to 1 provides
+	// no benefit, and makes the repository incompatible with older
+	// implementations of git).
+	Version_1 = "1"
+
+	// DefaultRepositoryFormatVersion holds the default repository format version.
+	DefaultRepositoryFormatVersion = Version_0
+)
+
+// ObjectFormat defines the object format.
+type ObjectFormat string
+
+const (
+	// SHA1 represents the object format used for SHA1.
+	SHA1 ObjectFormat = "sha1"
+
+	// SHA256 represents the object format used for SHA256.
+	SHA256 ObjectFormat = "sha256"
+
+	// DefaultObjectFormat holds the default object format.
+	DefaultObjectFormat = SHA1
+)
diff --git a/plumbing/format/config/section.go b/plumbing/format/config/section.go
index 07f72f3..4625ac5 100644
--- a/plumbing/format/config/section.go
+++ b/plumbing/format/config/section.go
@@ -103,7 +103,7 @@ func (s *Section) RemoveSubsection(name string) *Section {
 	return s
 }
 
-// Option return the value for the specified key. Empty string is returned if
+// Option returns the value for the specified key. Empty string is returned if
 // key does not exists.
 func (s *Section) Option(key string) string {
 	return s.Options.Get(key)