test: add unit tests for DoWithBackoff

Author: 0xaboomar

internal/config/backoff_time_store_test.go

@@ -0,0 +1,85 @@
+package config
+
+import (
+	"context"
+	"errors"
+	"net/http"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestDoWithBackoff(t *testing.T) {
+	tests := []struct {
+		name          string
+		maxRetries    int
+		ctxTimeout    time.Duration
+		handler       func(req *http.Request) (*http.Response, error)
+		expectErr     string
+		expectCalls   int
+		expectSuccess bool
+	}{
+		{
+			name:       "success on first try",
+			maxRetries: 3,
+			handler: func(req *http.Request) (*http.Response, error) {
+				return &http.Response{StatusCode: 200, Body: http.NoBody}, nil
+			},
+			expectErr:     "",
+			expectCalls:   1,
+			expectSuccess: true,
+		},
+		{
+			name:       "max retries exceeded",
+			maxRetries: 2,
+			handler: func(req *http.Request) (*http.Response, error) {
+				return nil, errors.New("mock error")
+			},
+			expectErr:   "max retries exceeded",
+			expectCalls: 3,
+		},
+		{
+			name:       "context cancelled before success",
+			maxRetries: 0,
+			ctxTimeout: 50 * time.Millisecond,
+			handler: func(req *http.Request) (*http.Response, error) {
+				return nil, errors.New("fail")
+			},
+			expectErr:   "context deadline exceeded",
+			expectCalls: -1,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			mock := &mockRoundTripper{handler: tt.handler}
+			client := &http.Client{Transport: mock}
+			req, _ := http.NewRequest("GET", "http://example.com", nil)
+
+			ctx := context.Background()
+			if tt.ctxTimeout > 0 {
+				var cancel context.CancelFunc
+				ctx, cancel = context.WithTimeout(ctx, tt.ctxTimeout)
+				defer cancel()
+			}
+
+			resp, err := DoWithBackoff(ctx, client, req, tt.maxRetries)
+
+			if tt.expectErr == "" && err != nil {
+				t.Fatalf("expected success, got error: %v", err)
+			}
+			if tt.expectErr != "" {
+				if err == nil || !strings.Contains(err.Error(), tt.expectErr) {
+					t.Fatalf("expected error containing %q, got %v", tt.expectErr, err)
+				}
+			}
+			if tt.expectSuccess && resp == nil {
+				t.Fatalf("expected response, got nil")
+			}
+
+			if tt.expectCalls >= 0 && mock.calls != tt.expectCalls {
+				t.Errorf("expected %d calls, got %d", tt.expectCalls, mock.calls)
+			}
+		})
+	}
+}

internal/config/test_helpers.go

@@ -0,0 +1,13 @@
+package config
+
+import "net/http"
+
+type mockRoundTripper struct {
+	calls   int
+	handler func(req *http.Request) (*http.Response, error)
+}
+
+func (m *mockRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	m.calls++
+	return m.handler(req)
+}