feature: add GetDefault func for map interface

README.md

@@ -436,6 +436,7 @@ Implements [Container](#containers) interface.
 type Map interface {
 	Put(key interface{}, value interface{})
 	Get(key interface{}) (value interface{}, found bool)
+	GetDefault(key interface{}, defaultValue interface{}) (value interface{})
 	Remove(key interface{})
 	Keys() []interface{}
 
@@ -476,6 +477,8 @@ func main() {
 	m.Put(1, "a")      // 2->b, 1->a (random order)
 	_, _ = m.Get(2)    // b, true
 	_, _ = m.Get(3)    // nil, false
+	_ = m.GetDefault(2, "8")  // b 
+	_ = m.GetDefault(3, "8")  // 8 
 	_ = m.Values()     // []interface {}{"b", "a"} (random order)
 	_ = m.Keys()       // []interface {}{1, 2} (random order)
 	m.Remove(1)        // 2->b
@@ -503,6 +506,8 @@ func main() {
 	m.Put(1, "a")                       // 1->a, 2->b (in order)
 	_, _ = m.Get(2)                     // b, true
 	_, _ = m.Get(3)                     // nil, false
+    _ = m.GetDefault(2, "8")            // b 
+	_ = m.GetDefault(3, "8")            // 8 
 	_ = m.Values()                      // []interface {}{"a", "b"} (in order)
 	_ = m.Keys()                        // []interface {}{1, 2} (in order)
 	m.Remove(1)                         // 2->b
@@ -534,6 +539,8 @@ func main() {
 	m.Put(1, "a")            // 2->b, 1->a (insertion-order)
 	_, _ = m.Get(2)          // b, true
 	_, _ = m.Get(3)          // nil, false
+	_ = m.GetDefault(2, "8") // b 
+	_ = m.GetDefault(3, "8") // 8 
 	_ = m.Values()           // []interface {}{"b", "a"} (insertion-order)
 	_ = m.Keys()             // []interface {}{2, 1} (insertion-order)
 	m.Remove(1)              // 2->b
@@ -564,6 +571,8 @@ func main() {
 	_, _ = m.GetKey("a")   // 1, true
 	_, _ = m.Get(2)        // b, true
 	_, _ = m.Get(3)        // nil, false
+    _ = m.GetDefault(2, "8")  // b 
+	_ = m.GetDefault(3, "8")  // 8 
 	_ = m.Values()         // []interface {}{"a", "b"} (random order)
 	_ = m.Keys()           // []interface {}{1, 2} (random order)
 	m.Remove(1)            // 2->b
@@ -596,6 +605,8 @@ func main() {
 	_, _ = m.GetKey("a") // 1, true
 	_, _ = m.Get(2)      // b, true
 	_, _ = m.Get(3)      // nil, false
+	_ = m.GetDefault(2, "8")  // b 
+	_ = m.GetDefault(3, "8")  // 8 
 	_ = m.Values()       // []interface {}{"a", "b"} (ordered)
 	_ = m.Keys()         // []interface {}{1, 2} (ordered)
 	m.Remove(1)          // 2->b

maps/hashbidimap/hashbidimap.go

@@ -59,6 +59,16 @@ func (m *Map) GetKey(value interface{}) (key interface{}, found bool) {
 	return m.inverseMap.Get(value)
 }
 
+// Get searches the element in the map by key and returns its value of default value given by second argument if key is not found in map.
+func (m *Map) GetDefault(key interface{}, defaultValue interface{}) (value interface{}) {
+	var found bool = false
+	value, found = m.Get(key)
+	if !found {
+		value = defaultValue
+	}
+	return
+}
+
 // Remove removes the element from the map by key.
 func (m *Map) Remove(key interface{}) {
 	if value, found := m.forwardMap.Get(key); found {

maps/hashbidimap/hashbidimap_test.go

@@ -7,6 +7,7 @@ package hashbidimap
 import (
 	"encoding/json"
 	"fmt"
+	"reflect"
 	"strings"
 	"testing"
 )
@@ -152,6 +153,21 @@ func TestMapGetKey(t *testing.T) {
 	}
 }
 
+func TestMapGetDefault(t *testing.T) {
+	m := New()
+	m.Put("c", 3)
+	m.Put("a", 1)
+	m.Put("b", 2)
+	val1 := m.GetDefault("c", 8)
+	if !reflect.DeepEqual(val1, 3) {
+		t.Errorf("Got %v expected %v", val1, 3)
+	}
+	val2 := m.GetDefault("e", 8)
+	if !reflect.DeepEqual(val2, 8) {
+		t.Errorf("Got %v expected %v", val2, 8)
+	}
+}
+
 func TestMapSerialization(t *testing.T) {
 	m := New()
 	m.Put("a", 1.0)

maps/hashmap/hashmap.go

@@ -13,6 +13,7 @@ package hashmap
 
 import (
 	"fmt"
+
 	"github.com/emirpasic/gods/maps"
 )
 
@@ -41,6 +42,16 @@ func (m *Map) Get(key interface{}) (value interface{}, found bool) {
 	return
 }
 
+// Get searches the element in the map by key and returns its value of default value given by second argument if key is not found in map.
+func (m *Map) GetDefault(key interface{}, defaultValue interface{}) (value interface{}) {
+	var found bool = false
+	value, found = m.Get(key)
+	if !found {
+		value = defaultValue
+	}
+	return
+}
+
 // Remove removes the element from the map by key.
 func (m *Map) Remove(key interface{}) {
 	delete(m.m, key)

maps/hashmap/hashmap_test.go

@@ -7,6 +7,7 @@ package hashmap
 import (
 	"encoding/json"
 	"fmt"
+	"reflect"
 	"strings"
 	"testing"
 )
@@ -120,6 +121,21 @@ func TestMapRemove(t *testing.T) {
 	}
 }
 
+func TestMapGetDefault(t *testing.T) {
+	m := New()
+	m.Put("c", 3)
+	m.Put("a", 1)
+	m.Put("b", 2)
+	val1 := m.GetDefault("c", 8)
+	if !reflect.DeepEqual(val1, 3) {
+		t.Errorf("Got %v expected %v", val1, 3)
+	}
+	val2 := m.GetDefault("e", 8)
+	if !reflect.DeepEqual(val2, 8) {
+		t.Errorf("Got %v expected %v", val2, 8)
+	}
+}
+
 func TestMapSerialization(t *testing.T) {
 	m := New()
 	m.Put("a", 1.0)

maps/linkedhashmap/linkedhashmap.go

@@ -53,6 +53,16 @@ func (m *Map) Get(key interface{}) (value interface{}, found bool) {
 	return
 }
 
+// Get searches the element in the map by key and returns its value of default value given by second argument if key is not found in map.
+func (m *Map) GetDefault(key interface{}, defaultValue interface{}) (value interface{}) {
+	var found bool = false
+	value, found = m.Get(key)
+	if !found {
+		value = defaultValue
+	}
+	return
+}
+
 // Remove removes the element from the map by key.
 // Key should adhere to the comparator's type assertion, otherwise method panics.
 func (m *Map) Remove(key interface{}) {

maps/linkedhashmap/linkedhashmap_test.go

@@ -7,6 +7,7 @@ package linkedhashmap
 import (
 	"encoding/json"
 	"fmt"
+	"reflect"
 	"strings"
 	"testing"
 )
@@ -210,6 +211,21 @@ func TestMapSelect(t *testing.T) {
 	}
 }
 
+func TestMapGetDefault(t *testing.T) {
+	m := New()
+	m.Put("c", 3)
+	m.Put("a", 1)
+	m.Put("b", 2)
+	val1 := m.GetDefault("c", 8)
+	if !reflect.DeepEqual(val1, 3) {
+		t.Errorf("Got %v expected %v", val1, 3)
+	}
+	val2 := m.GetDefault("e", 8)
+	if !reflect.DeepEqual(val2, 8) {
+		t.Errorf("Got %v expected %v", val2, 8)
+	}
+}
+
 func TestMapAny(t *testing.T) {
 	m := New()
 	m.Put("c", 3)

maps/maps.go

@@ -21,6 +21,7 @@ import "github.com/emirpasic/gods/containers"
 type Map interface {
 	Put(key interface{}, value interface{})
 	Get(key interface{}) (value interface{}, found bool)
+	GetDefault(key interface{}, defaultValue interface{}) (value interface{})
 	Remove(key interface{})
 	Keys() []interface{}
 

maps/treebidimap/treebidimap.go

@@ -19,10 +19,11 @@ package treebidimap
 
 import (
 	"fmt"
+	"strings"
+
 	"github.com/emirpasic/gods/maps"
 	"github.com/emirpasic/gods/trees/redblacktree"
 	"github.com/emirpasic/gods/utils"
-	"strings"
 )
 
 // Assert Map implementation
@@ -83,6 +84,16 @@ func (m *Map) Get(key interface{}) (value interface{}, found bool) {
 	return nil, false
 }
 
+// Get searches the element in the map by key and returns its value of default value given by second argument if key is not found in map.
+func (m *Map) GetDefault(key interface{}, defaultValue interface{}) (value interface{}) {
+	var found bool = false
+	value, found = m.Get(key)
+	if !found {
+		value = defaultValue
+	}
+	return
+}
+
 // GetKey searches the element in the map by value and returns its key or nil if value is not found in map.
 // Second return parameter is true if value was found, otherwise false.
 func (m *Map) GetKey(value interface{}) (key interface{}, found bool) {

maps/treebidimap/treebidimap_test.go

@@ -7,9 +7,11 @@ package treebidimap
 import (
 	"encoding/json"
 	"fmt"
-	"github.com/emirpasic/gods/utils"
+	"reflect"
 	"strings"
 	"testing"
+
+	"github.com/emirpasic/gods/utils"
 )
 
 func TestMapPut(t *testing.T) {
@@ -153,6 +155,21 @@ func TestMapGetKey(t *testing.T) {
 	}
 }
 
+func TestGetDefault(t *testing.T) {
+	m := NewWith(utils.StringComparator, utils.IntComparator)
+	m.Put("c", 3)
+	m.Put("a", 1)
+	m.Put("b", 2)
+	val1 := m.GetDefault("c", 8)
+	if !reflect.DeepEqual(val1, 3) {
+		t.Errorf("Got %v expected %v", val1, 3)
+	}
+	val2 := m.GetDefault("e", 8)
+	if !reflect.DeepEqual(val2, 8) {
+		t.Errorf("Got %v expected %v", val2, 8)
+	}
+}
+
 func sameElements(a []interface{}, b []interface{}) bool {
 	if len(a) != len(b) {
 		return false

maps/treemap/treemap.go

@@ -13,10 +13,11 @@ package treemap
 
 import (
 	"fmt"
+	"strings"
+
 	"github.com/emirpasic/gods/maps"
 	rbt "github.com/emirpasic/gods/trees/redblacktree"
 	"github.com/emirpasic/gods/utils"
-	"strings"
 )
 
 // Assert Map implementation
@@ -55,6 +56,16 @@ func (m *Map) Get(key interface{}) (value interface{}, found bool) {
 	return m.tree.Get(key)
 }
 
+// Get searches the element in the map by key and returns its value of default value given by second argument if key is not found in map.
+func (m *Map) GetDefault(key interface{}, defaultValue interface{}) (value interface{}) {
+	var found bool = false
+	value, found = m.Get(key)
+	if !found {
+		value = defaultValue
+	}
+	return
+}
+
 // Remove removes the element from the map by key.
 // Key should adhere to the comparator's type assertion, otherwise method panics.
 func (m *Map) Remove(key interface{}) {

maps/treemap/treemap_test.go

@@ -7,9 +7,11 @@ package treemap
 import (
 	"encoding/json"
 	"fmt"
-	"github.com/emirpasic/gods/utils"
+	"reflect"
 	"strings"
 	"testing"
+
+	"github.com/emirpasic/gods/utils"
 )
 
 func TestMapPut(t *testing.T) {
@@ -391,6 +393,21 @@ func TestMapFind(t *testing.T) {
 	}
 }
 
+func TestMapGetDefault(t *testing.T) {
+	m := NewWithStringComparator()
+	m.Put("c", 3)
+	m.Put("a", 1)
+	m.Put("b", 2)
+	val1 := m.GetDefault("c", 8)
+	if !reflect.DeepEqual(val1, 3) {
+		t.Errorf("Got %v expected %v", val1, 3)
+	}
+	val2 := m.GetDefault("e", 8)
+	if !reflect.DeepEqual(val2, 8) {
+		t.Errorf("Got %v expected %v", val2, 8)
+	}
+}
+
 func TestMapChaining(t *testing.T) {
 	m := NewWithStringComparator()
 	m.Put("c", 3)