u4: add core infrastructure scaffolding

1 files changed, 81 insertions, 0 deletions

diff --git a/internal/httpctx/httpctx_test.go b/internal/httpctx/httpctx_test.go
new file mode 100644
index 0000000..ffad68c
--- /dev/null
+++ b/internal/httpctx/httpctx_test.go
@@ -0,0 +1,81 @@
+package httpctx
+
+import (
+	"context"
+	"net/http"
+	"testing"
+	"time"
+
+	"google.golang.org/genai"
+)
+
+func TestWithTimeoutUnlessSet_AlreadyHasDeadline(t *testing.T) {
+	t.Parallel()
+
+	parent, cancel := context.WithTimeout(context.Background(), time.Hour)
+	defer cancel()
+
+	ctx, childCancel := WithTimeoutUnlessSet(parent, time.Nanosecond)
+	defer childCancel()
+
+	if ctx != parent {
+		t.Fatal("expected same context when parent already has deadline")
+	}
+}
+
+func TestWithTimeoutUnlessSet_NoDeadline(t *testing.T) {
+	t.Parallel()
+
+	ctx, cancel := WithTimeoutUnlessSet(context.Background(), 50*time.Millisecond)
+	defer cancel()
+
+	deadline, ok := ctx.Deadline()
+	if !ok {
+		t.Fatal("expected deadline")
+	}
+	if time.Until(deadline) > time.Second {
+		t.Fatalf("deadline too far: %v", deadline)
+	}
+}
+
+func TestWithTimeoutUnlessSet_NilUsesBackground(t *testing.T) {
+	t.Parallel()
+
+	ctx, cancel := WithTimeoutUnlessSet(nil, 50*time.Millisecond)
+	defer cancel()
+
+	if err := ctx.Err(); err != nil {
+		t.Fatalf("context should not be done: %v", err)
+	}
+}
+
+func TestNewGenAIClientAppliesDefaultHTTPClient(t *testing.T) {
+	t.Parallel()
+
+	customClient := &http.Client{Timeout: time.Second}
+	cfg := &genai.ClientConfig{
+		APIKey: "test-key",
+	}
+
+	client, err := NewGenAIClient(context.Background(), cfg)
+	if err != nil {
+		t.Fatalf("NewGenAIClient() error = %v", err)
+	}
+	if client == nil {
+		t.Fatal("NewGenAIClient() client = nil")
+	}
+	if cfg.HTTPClient != nil {
+		t.Fatalf("NewGenAIClient() mutated input config HTTPClient = %#v, want nil", cfg.HTTPClient)
+	}
+
+	cfg2 := &genai.ClientConfig{
+		APIKey:     "test-key",
+		HTTPClient: customClient,
+	}
+	if _, err := NewGenAIClient(context.Background(), cfg2); err != nil {
+		t.Fatalf("NewGenAIClient() error = %v", err)
+	}
+	if cfg2.HTTPClient != customClient {
+		t.Fatal("NewGenAIClient() should preserve caller HTTPClient")
+	}
+}