Merge pull request #177 from Flipez/array-join

[object/array] Add ability to `.join()` elements

docs/docs/literals/array.md

@@ -62,6 +62,15 @@ Returns the index of the given element in the array if found. Otherwise return `
 ' />
 
 
+### join(STRING)
+> Returns `STRING`
+
+
+
+
+
+
+
 ### last()
 > Returns `STRING|ARRAY|HASH|BOOLEAN|INTEGER|NIL|FUNCTION|FILE`
 

object/array.go

@@ -67,6 +67,35 @@ func (ao *Array) index(obj Object) int {
 
 func init() {
 	objectMethods[ARRAY_OBJ] = map[string]ObjectMethod{
+		"join": ObjectMethod{
+			Layout: MethodLayout{
+				ReturnPattern: Args(
+					Arg(STRING_OBJ),
+				),
+				ArgPattern: Args(
+					OptArg(STRING_OBJ),
+				),
+			},
+			method: func(o Object, args []Object, _ Environment) Object {
+				ao := o.(*Array)
+				arr := make([]string, len(ao.Elements))
+				join := ""
+
+				if len(args) > 0 {
+					join = args[0].(*String).Value
+				}
+
+				for i, element := range ao.Elements {
+					if e, ok := element.(Stringable); ok {
+						arr[i] = e.ToStringObj(nil).Value
+					} else {
+						return NewErrorFormat("Found non stringable element %s on index %d", element.Type(), i)
+					}
+				}
+
+				return NewString(strings.Join(arr, join))
+			},
+		},
 		"reverse": ObjectMethod{
 			Layout: MethodLayout{
 				ReturnPattern: Args(

object/array_test.go

@@ -69,6 +69,9 @@ func TestArrayObjectMethods(t *testing.T) {
 		{`[1,2,3,4,5,6,7,8].slices(3)`, `[[1, 2, 3], [4, 5, 6], [7, 8]]`},
 		{`[1,2].slices(3)`, `[[1, 2]]`},
 		{`[1,2].slices(0)`, `invalid slice size, needs to be > 0`},
+		{"[1,2,3,{}].join()", "Found non stringable element HASH on index 3"},
+		{"[1,2,3].join()", "123"},
+		{"[1,2,3].join('-')", "1-2-3"},
 	}
 
 	testInput(t, tests)