Function TestCursorAccumulateResultUsage

server/pkg/agent/cursor_test.go:297–387

(t *testing.T)

}

func TestCursorAccumulateResultUsage(t *testing.T) {
	t.Parallel()

	b := &cursorBackend{cfg: Config{Logger: slog.Default()}}

	// Nested usage object (snake_case keys) — compatible with
	// cursor-agent versions that wrap usage in a sub-object.
	t.Run("nested_usage_object", func(t *testing.T) {
		usage := make(map[string]TokenUsage)
		evt := &cursorStreamEvent{
			Model: "gpt-5.3",
			Usage: &cursorUsage{
				InputTokens:           200,
				OutputTokens:          100,
				CacheReadInputTokens:  50,
				CacheWriteInputTokens: 25,
			},
		}
		b.accumulateResultUsage(usage, evt, "")
		u := usage["gpt-5.3"]
		if u.InputTokens != 200 || u.OutputTokens != 100 || u.CacheReadTokens != 50 || u.CacheWriteTokens != 25 {
			t.Fatalf("unexpected usage: %+v", u)
		}
	})

	// Top-level camelCase fields (cursor-agent v0.46+) — the current
	// default shape from the Cursor CLI. When present, they take
	// precedence over any nested usage object.
	t.Run("top_level_camelcase", func(t *testing.T) {
		usage := make(map[string]TokenUsage)
		evt := &cursorStreamEvent{
			Model:            "gpt-5.3",
			InputTokens:      300,
			OutputTokens:     150,
			CacheReadTokens:  75,
			CacheWriteTokens: 25,
		}
		b.accumulateResultUsage(usage, evt, "")
		u := usage["gpt-5.3"]
		if u.InputTokens != 300 || u.OutputTokens != 150 || u.CacheReadTokens != 75 || u.CacheWriteTokens != 25 {
			t.Fatalf("unexpected usage: %+v (want input=300 output=150 cache_read=75 cache_write=25)", u)
		}
	})

	// Top-level fields win when both shapes are present — this
	// prevents double-counting from the nested fallback.
	t.Run("top_level_wins_over_nested", func(t *testing.T) {
		usage := make(map[string]TokenUsage)
		evt := &cursorStreamEvent{
			Model:        "gpt-5.3",
			InputTokens:  300,
			OutputTokens: 150,
			Usage: &cursorUsage{
				InputTokens:          999,
				OutputTokens:         888,
				CacheReadInputTokens: 777,
			},
		}