Merge pull request #114 from samber/feat-get-map

Get: retrieves the value of a path of *map*

Author: thoas

README.rst

@@ -343,7 +343,7 @@ Manipulates an iteratee (map, slice) and transforms it to to a flattened collect
 funk.Get
 ........
 
-Retrieves the value at path of struct(s).
+Retrieves the value at path of struct(s) or map(s).
 
 .. code-block:: go
 
@@ -381,6 +381,34 @@ Retrieves the value at path of struct(s).
     funk.Get(foo, "Bar.Bars.Bar.Name") // []string{"Level2-1", "Level2-2"}
     funk.Get(foo, "Bar.Name") // Test
 
+``funk.Get`` also support ``map`` values:
+
+.. code-block:: go
+
+    bar := map[string]interface{}{
+        "Name": "Test",
+    }
+
+    foo1 := map[string]interface{}{
+        "ID":        1,
+        "FirstName": "Dark",
+        "LastName":  "Vador",
+        "Age":       30,
+        "Bar":       bar,
+    }
+
+    foo2 := &map[string]interface{}{
+        "ID":        1,
+        "FirstName": "Dark",
+        "LastName":  "Vador",
+        "Age":       30,
+    } // foo2.Bar is nil
+
+    funk.Get(bar, "Name") // "Test"
+    funk.Get([]map[string]interface{}{foo1, foo2}, "Bar.Name") // []string{"Test"}
+    funk.Get(foo2, "Bar.Name") // nil
+
+
 ``funk.Get`` also handles ``nil`` values:
 
 .. code-block:: go

funk_test.go

@@ -78,3 +78,34 @@ var foo2 = &Foo{
 	LastName:  "Vador",
 	Age:       30,
 }
+
+var m1 = map[string]interface{}{
+	"id":        1,
+	"firstname": "dark",
+	"lastname":  "vador",
+	"age":       30,
+	"bar": map[string]interface{}{
+		"name": "test",
+		"bars": []map[string]interface{}{
+			{
+				"name": "level1-1",
+				"bar": map[string]interface{}{
+					"name": "level2-1",
+				},
+			},
+			{
+				"name": "level1-2",
+				"bar": map[string]interface{}{
+					"name": "level2-2",
+				},
+			},
+		},
+	},
+}
+
+var m2 = map[string]interface{}{
+	"id":        1,
+	"firstname": "dark",
+	"lastname":  "vador",
+	"age":       30,
+}

retrieve.go

@@ -47,7 +47,7 @@ func get(value reflect.Value, path string) reflect.Value {
 		}
 
 		// if the result is a slice of a slice, we need to flatten it
-		if resultSlice.Type().Elem().Kind() == reflect.Slice {
+		if resultSlice.Kind() != reflect.Invalid && resultSlice.Type().Elem().Kind() == reflect.Slice {
 			return flattenDeep(resultSlice)
 		}
 
@@ -60,18 +60,17 @@ func get(value reflect.Value, path string) reflect.Value {
 		value = redirectValue(value)
 		kind := value.Kind()
 
-		if kind == reflect.Invalid {
+		switch kind {
+		case reflect.Invalid:
 			continue
-		}
-
-		if kind == reflect.Struct {
+		case reflect.Struct:
 			value = value.FieldByName(part)
-			continue
-		}
-
-		if kind == reflect.Slice || kind == reflect.Array {
+		case reflect.Map:
+			value = value.MapIndex(reflect.ValueOf(part))
+		case reflect.Slice, reflect.Array:
 			value = get(value, part)
-			continue
+		default:
+			return reflect.ValueOf(nil)
 		}
 	}
 

retrieve_test.go

@@ -35,13 +35,36 @@ func TestGetNil(t *testing.T) {
 	is.Equal(Get([]*Foo{foo, foo2}, "Bar.Name"), []string{"Test"})
 }
 
+func TestGetMap(t *testing.T) {
+	is := assert.New(t)
+	m := map[string]interface{}{
+		"bar": map[string]interface{}{
+			"name": "foobar",
+		},
+	}
+
+	is.Equal("foobar", Get(m, "bar.name"))
+	is.Equal(nil, Get(m, "foo.name"))
+	is.Equal([]interface{}{"dark", "dark"}, Get([]map[string]interface{}{m1, m2}, "firstname"))
+	is.Equal([]interface{}{"test"}, Get([]map[string]interface{}{m1, m2}, "bar.name"))
+}
+
 func TestGetThroughInterface(t *testing.T) {
 	is := assert.New(t)
 
 	is.Equal(Get(foo, "BarInterface.Bars.Bar.Name"), []string{"Level2-1", "Level2-2"})
 	is.Equal(Get(foo, "BarPointer.Bars.Bar.Name"), []string{"Level2-1", "Level2-2"})
 }
 
+func TestGetNotFound(t *testing.T) {
+	is := assert.New(t)
+
+	is.Equal(nil, Get(foo, "id"))
+	is.Equal(nil, Get(foo, "id.id"))
+	is.Equal(nil, Get(foo, "Bar.id"))
+	is.Equal(nil, Get(foo, "Bars.id"))
+}
+
 func TestGetSimple(t *testing.T) {
 	is := assert.New(t)
 
@@ -68,5 +91,4 @@ func TestGetOrElse(t *testing.T) {
 		// test GetOrElse coveers this case
 		is.Equal("foobar", GetOrElse((*string)(nil), "foobar"))
 	})
-
 }