feat: initial version

2025-06-07 19:23:44 +02:00
commit 26eff55974
12 changed files with 452 additions and 0 deletions
@@ -0,0 +1,105 @@
+package pagination
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGetPage(t *testing.T) {
+	type args[T any] struct {
+		items  []T
+		first  *int
+		after  *string
+		last   *int
+		before *string
+		max    int
+		fn     func(T) string
+	}
+	type testCase[T any] struct {
+		name         string
+		args         args[T]
+		wantItems    []T
+		wantPageInfo PageInfo
+	}
+	tests := []testCase[string]{
+		{
+			name:         "empty",
+			args:         args[string]{max: 10},
+			wantItems:    nil,
+			wantPageInfo: PageInfo{},
+		},
+		{
+			name:      "first 2",
+			args:      args[string]{items: []string{"1", "2", "3"}, first: ptr(2), max: 10, fn: func(s string) string { return s }},
+			wantItems: []string{"1", "2"},
+			wantPageInfo: PageInfo{
+				StartCursor: ptr("MQ=="),
+				HasNextPage: true,
+				EndCursor:   ptr("Mg=="),
+			},
+		},
+		{
+			name:      "after 2",
+			args:      args[string]{items: []string{"1", "2", "3", "4"}, first: ptr(2), after: ptr("Mg=="), max: 10, fn: func(s string) string { return s }},
+			wantItems: []string{"3", "4"},
+			wantPageInfo: PageInfo{
+				StartCursor:     ptr("Mw=="),
+				HasNextPage:     false,
+				HasPreviousPage: true,
+				EndCursor:       ptr("NA=="),
+			},
+		},
+		{
+			name:      "end of items",
+			args:      args[string]{items: []string{"1", "2", "3"}, first: ptr(2), after: ptr("Mg=="), max: 10, fn: func(s string) string { return s }},
+			wantItems: []string{"3"},
+			wantPageInfo: PageInfo{
+				StartCursor:     ptr("Mw=="),
+				HasNextPage:     false,
+				HasPreviousPage: true,
+				EndCursor:       ptr("Mw=="),
+			},
+		},
+		{
+			name:      "last 2",
+			args:      args[string]{items: []string{"1", "2", "3"}, last: ptr(2), max: 10, fn: func(s string) string { return s }},
+			wantItems: []string{"2", "3"},
+			wantPageInfo: PageInfo{
+				StartCursor:     ptr("Mg=="),
+				HasNextPage:     false,
+				HasPreviousPage: true,
+				EndCursor:       ptr("Mw=="),
+			},
+		},
+		{
+			name:      "before 3",
+			args:      args[string]{items: []string{"1", "2", "3"}, last: ptr(2), before: ptr("Mw=="), max: 10, fn: func(s string) string { return s }},
+			wantItems: []string{"1", "2"},
+			wantPageInfo: PageInfo{
+				StartCursor:     ptr("MQ=="),
+				HasNextPage:     true,
+				HasPreviousPage: false,
+				EndCursor:       ptr("Mg=="),
+			},
+		},
+		{
+			name:      "before 2",
+			args:      args[string]{items: []string{"1", "2", "3"}, last: ptr(2), before: ptr("Mg=="), max: 10, fn: func(s string) string { return s }},
+			wantItems: []string{"1"},
+			wantPageInfo: PageInfo{
+				StartCursor:     ptr("MQ=="),
+				HasNextPage:     true,
+				HasPreviousPage: false,
+				EndCursor:       ptr("MQ=="),
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, got1 := GetPage(tt.args.items, tt.args.first, tt.args.after, tt.args.last, tt.args.before, tt.args.max, tt.args.fn)
+			assert.Equalf(t, tt.wantItems, got, "GetPage(%v, %v, %v, %v, %v, %v)", tt.args.items, tt.args.first, tt.args.after, tt.args.last, tt.args.before, tt.args.max)
+			assert.Equalf(t, tt.wantPageInfo, got1, "GetPage(%v, %v, %v, %v, %v, %v)", tt.args.items, tt.args.first, tt.args.after, tt.args.last, tt.args.before, tt.args.max)
+		})
+	}
+}