ini: add method to Rebase other INI object

Basically, Rebase merge each sections in other INI object on top of
current INI object.

2 files changed, 61 insertions, 0 deletions

diff --git a/lib/ini/ini.go b/lib/ini/ini.go
index 01807d5b..7c94a0ac 100644
--- a/lib/ini/ini.go
+++ b/lib/ini/ini.go
@@ -303,6 +303,15 @@ func mergeSection(secs []*Section, newSec *Section) []*Section {
 }
 
 //
+// Rebase merge the other INI sections into this INI sections.
+//
+func (in *Ini) Rebase(other *Ini) {
+	for _, otherSec := range other.secs {
+		in.secs = mergeSection(in.secs, otherSec)
+	}
+}
+
+//
 // Save the current parsed Ini into file `filename`. It will overwrite the
 // destination file if it's exist.
 //
diff --git a/lib/ini/ini_example_test.go b/lib/ini/ini_example_test.go
index 8ea5efbd..328ce780 100644
--- a/lib/ini/ini_example_test.go
+++ b/lib/ini/ini_example_test.go
@@ -106,3 +106,55 @@ key=value1
 	// key = value2
 	// key = value1
 }
+
+func ExampleIni_Rebase() {
+	input := []byte(`
+		[section]
+		key=value1
+		key2=
+
+		[section "sub"]
+		key=value1
+`)
+
+	other := []byte(`
+		[section]
+		key=value2
+		key2=false
+
+		[section "sub"]
+		key=value2
+		key=value1
+`)
+
+	in, err := Parse(input)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	in2, err := Parse(other)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	in.Prune()
+	in2.Prune()
+
+	in.Rebase(in2)
+
+	for _, sec := range in.secs {
+		fmt.Printf("%s", sec)
+		for _, v := range sec.Vars {
+			fmt.Printf("%s", v)
+		}
+	}
+	// Output:
+	// [section]
+	// key = value1
+	// key2 = true
+	// key = value2
+	// key2 = false
+	// [section "sub"]
+	// key = value2
+	// key = value1
+}