3 files changed, 141 insertions, 0 deletions
diff --git a/tpl/reflect/init.go b/tpl/reflect/init.go
new file mode 100644
index 000000000..3af6dfa11
--- /dev/null
+++ b/tpl/reflect/init.go
@@ -0,0 +1,51 @@
+// Copyright 2018 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package reflect provides template functions for run-time object reflection.
+package reflect
+
+import (
+	"github.com/gohugoio/hugo/deps"
+	"github.com/gohugoio/hugo/tpl/internal"
+)
+
+const name = "reflect"
+
+func init() {
+	f := func(d *deps.Deps) *internal.TemplateFuncsNamespace {
+		ctx := New()
+
+		ns := &internal.TemplateFuncsNamespace{
+			Name:    name,
+			Context: func(args ...any) (any, error) { return ctx, nil },
+		}
+
+		ns.AddMethodMapping(ctx.IsMap,
+			nil,
+			[][2]string{
+				{`{{ if reflect.IsMap (dict "a" 1) }}Map{{ end }}`, `Map`},
+			},
+		)
+
+		ns.AddMethodMapping(ctx.IsSlice,
+			nil,
+			[][2]string{
+				{`{{ if reflect.IsSlice (slice 1 2 3) }}Slice{{ end }}`, `Slice`},
+			},
+		)
+
+		return ns
+	}
+
+	internal.AddTemplateFuncsNamespace(f)
+}
diff --git a/tpl/reflect/reflect.go b/tpl/reflect/reflect.go
new file mode 100644
index 000000000..07834be1c
--- /dev/null
+++ b/tpl/reflect/reflect.go
@@ -0,0 +1,36 @@
+// Copyright 2018 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package reflect
+
+import (
+	"reflect"
+)
+
+// New returns a new instance of the reflect-namespaced template functions.
+func New() *Namespace {
+	return &Namespace{}
+}
+
+// Namespace provides template functions for the "reflect" namespace.
+type Namespace struct{}
+
+// IsMap reports whether v is a map.
+func (ns *Namespace) IsMap(v any) bool {
+	return reflect.ValueOf(v).Kind() == reflect.Map
+}
+
+// IsSlice reports whether v is a slice.
+func (ns *Namespace) IsSlice(v any) bool {
+	return reflect.ValueOf(v).Kind() == reflect.Slice
+}
diff --git a/tpl/reflect/reflect_test.go b/tpl/reflect/reflect_test.go
new file mode 100644
index 000000000..f85af87dd
--- /dev/null
+++ b/tpl/reflect/reflect_test.go
@@ -0,0 +1,54 @@
+// Copyright 2018 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package reflect
+
+import (
+	"testing"
+
+	qt "github.com/frankban/quicktest"
+)
+
+var ns = New()
+
+type tstNoStringer struct{}
+
+func TestIsMap(t *testing.T) {
+	c := qt.New(t)
+	for _, test := range []struct {
+		v      any
+		expect any
+	}{
+		{map[int]int{1: 1}, true},
+		{"foo", false},
+		{nil, false},
+	} {
+		result := ns.IsMap(test.v)
+		c.Assert(result, qt.Equals, test.expect)
+	}
+}
+
+func TestIsSlice(t *testing.T) {
+	c := qt.New(t)
+	for _, test := range []struct {
+		v      any
+		expect any
+	}{
+		{[]int{1, 2}, true},
+		{"foo", false},
+		{nil, false},
+	} {
+		result := ns.IsSlice(test.v)
+		c.Assert(result, qt.Equals, test.expect)
+	}
+}