test: osvdevexperimental mock paging interface (#3783)

Test this implementation a bit more, and also makes it easier for users
to mock their own tests as well.

This is to support the work done on moving osvmatcher to osv-scalibr.

Author: another-rex

bindings/go/osvdevexperimental/paging.go

@@ -7,9 +7,14 @@ import (
 	"osv.dev/bindings/go/osvdev"
 )
 
+type OSVClientInterface interface {
+	Query(ctx context.Context, query *osvdev.Query) (*osvdev.Response, error)
+	QueryBatch(ctx context.Context, queries []*osvdev.Query) (*osvdev.BatchedResponse, error)
+}
+
 // QueryPaging performs a single query with the given OSVClient, and handles
 // paging logic to return all results.
-func QueryPaging(ctx context.Context, c *osvdev.OSVClient, query *osvdev.Query) (*osvdev.Response, error) {
+func QueryPaging(ctx context.Context, c OSVClientInterface, query *osvdev.Query) (*osvdev.Response, error) {
 	queryResponse, err := c.Query(ctx, query)
 
 	if err != nil {
@@ -56,7 +61,7 @@ func QueryPaging(ctx context.Context, c *osvdev.OSVClient, query *osvdev.Query)
 
 // BatchQueryPaging performs a batch query with the given OSVClient, and handles
 // paging logic for each query to return all results.
-func BatchQueryPaging(ctx context.Context, c *osvdev.OSVClient, queries []*osvdev.Query) (*osvdev.BatchedResponse, error) {
+func BatchQueryPaging(ctx context.Context, c OSVClientInterface, queries []*osvdev.Query) (*osvdev.BatchedResponse, error) {
 	batchResp, err := c.QueryBatch(ctx, queries)
 
 	if err != nil {

bindings/go/osvdevexperimental/paging_test.go

@@ -0,0 +1,142 @@
+package osvdevexperimental
+
+import (
+	"context"
+	"errors"
+	"github.com/ossf/osv-schema/bindings/go/osvschema"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"osv.dev/bindings/go/osvdev"
+)
+
+type mockOSVClient struct {
+	queryResponses     map[string]*osvdev.Response
+	batchQueryReponses map[string]*osvdev.BatchedResponse
+}
+
+func (m *mockOSVClient) Query(ctx context.Context, query *osvdev.Query) (*osvdev.Response, error) {
+	key := query.PageToken
+	if key == "" {
+		key = "first"
+	}
+	resp, ok := m.queryResponses[key]
+	if !ok {
+		return nil, errors.New("no response for query")
+	}
+	return resp, nil
+}
+
+func (m *mockOSVClient) QueryBatch(ctx context.Context, queries []*osvdev.Query) (*osvdev.BatchedResponse, error) {
+	// For simplicity, we'll just use the first query's page token to determine the response.
+	key := ""
+	if len(queries) > 0 {
+		key = queries[0].PageToken
+	}
+	if key == "" {
+		key = "first"
+	}
+
+	resp, ok := m.batchQueryReponses[key]
+	if !ok {
+		return nil, errors.New("no response for batch query")
+	}
+	return resp, nil
+}
+
+func TestQueryPaging(t *testing.T) {
+	mockClient := &mockOSVClient{
+		queryResponses: map[string]*osvdev.Response{
+			"first": {
+				Vulns: []osvschema.Vulnerability{
+					{ID: "VULN-1"},
+				},
+				NextPageToken: "page2",
+			},
+			"page2": {
+				Vulns: []osvschema.Vulnerability{
+					{ID: "VULN-2"},
+				},
+				NextPageToken: "page3",
+			},
+			"page3": {
+				Vulns: []osvschema.Vulnerability{
+					{ID: "VULN-3"},
+				},
+			},
+		},
+	}
+
+	query := &osvdev.Query{}
+	resp, err := QueryPaging(context.Background(), mockClient, query)
+	if err != nil {
+		t.Fatalf("QueryPaging failed: %v", err)
+	}
+
+	expectedVulns := []osvschema.Vulnerability{
+		{ID: "VULN-1"},
+		{ID: "VULN-2"},
+		{ID: "VULN-3"},
+	}
+
+	if diff := cmp.Diff(expectedVulns, resp.Vulns); diff != "" {
+		t.Errorf("QueryPaging returned unexpected vulns (-want +got):\n%s", diff)
+	}
+
+	if resp.NextPageToken != "" {
+		t.Errorf("Expected empty NextPageToken, got %s", resp.NextPageToken)
+	}
+}
+
+func TestBatchQueryPaging(t *testing.T) {
+	mockClient := &mockOSVClient{
+		batchQueryReponses: map[string]*osvdev.BatchedResponse{
+			"first": {
+				Results: []osvdev.MinimalResponse{
+					{ // Query 1, Page 1
+						Vulns:         []osvdev.MinimalVulnerability{{ID: "Q1-VULN-1"}},
+						NextPageToken: "q1page2",
+					},
+					{ // Query 2, Page 1
+						Vulns: []osvdev.MinimalVulnerability{{ID: "Q2-VULN-1"}},
+					},
+				},
+			},
+			"q1page2": {
+				Results: []osvdev.MinimalResponse{
+					{ // Query 1, Page 2
+						Vulns: []osvdev.MinimalVulnerability{{ID: "Q1-VULN-2"}},
+					},
+				},
+			},
+		},
+	}
+
+	queries := []*osvdev.Query{
+		{Commit: "q1"},
+		{Commit: "q2"},
+	}
+
+	resp, err := BatchQueryPaging(context.Background(), mockClient, queries)
+	if err != nil {
+		t.Fatalf("BatchQueryPaging failed: %v", err)
+	}
+
+	expectedResponses := []osvdev.MinimalResponse{
+		{
+			Vulns: []osvdev.MinimalVulnerability{
+				{ID: "Q1-VULN-1"},
+				{ID: "Q1-VULN-2"},
+			},
+		},
+		{
+			Vulns: []osvdev.MinimalVulnerability{
+				{ID: "Q2-VULN-1"},
+			},
+		},
+	}
+
+	if diff := cmp.Diff(expectedResponses, resp.Results, cmp.AllowUnexported(osvdev.Response{})); diff != "" {
+		t.Errorf("BatchQueryPaging returned unexpected results (-want +got):\n%s", diff)
+	}
+}