Unless you are living in Spain or a Spanish national, borders are closed at present (10 May 2020).  As JCaron pointed out, nobody knows whether it will be worse or better in July. But for today:

These are the people who are exempt from border restrictions:

Air, land and sea borders

Only Spanish citizens or those who can prove residency in Spain by presenting a green residency certificate, are allowed to enter Spain through airports, ports or land borders.

The following categories of people are also exempt from border restrictions:

• Frontier workers
• Health workers
• Those who are transiting Spain to their country of residence in EU/Schengen area
• Those with a Schengen visa who are transiting Spain to their country of residence in EU/Schengen area
• Those who can prove that they need to enter Spain for essential reasons

(Source)

The Coronavirus is still a health crisis and would highly not recommend travelling even if you live there as you have another residence in France I assume. That is then not essential but recreational travel.

Regarding France, while you may technically be able to enter the country (if you are an EU/EEA citizen or resident), you are not allowed to travel inside the country except for specific listed purposes (professional travel, funeral…) Going on holiday or switching residences is not allowed.

The rules are set to change tomorrow (May 11) and short trips inside the country will be allowed again. I haven't been able to find the new forms but similar restrictions should however still apply to travel longer than 100 km.

The French government hasn't announced when these new restrictions could be lifted. The official stance is that this would be evaluated at the end of May.

As other answers have told, in the current situation the rules will change as a result of the spread and control of Covid. The more controlled it is, the more lenient you can expect the rules to become.

I will just explain the current status in Spain so you can make your own evaluation.

As of now, travel between Spanish provinces is restricted to essential travel. Moving to a second residence is not essential travel.

Spain is currently implementing a plan to de-escalate restrictions, in which regions (often provinces, but not always) where the disease seems to be under control with be allowed more lenient rules.

Today a significant part of Spain will get into "phase 1", the rest will remain at "phase 0". At "phase 1" there are reduced movility restrictions within your zone (you can move to a secondary residence in the same zone in phase 1, but not in phase 0) but movement between zones is still restricted to essential travel.

Each two weeks conditions will be evaluated and it may be decided that a zone advances to the next phase, remains at the current one or even returns to a previous phase. There are a total of 4 phases.

Given that Spain's economy depends a great deal on tourism, if conditions allow for most of the country to reach phase 4 it is to be expected that the entry of foreign visitors will be eased.

Yet it remains to be seen if phase 4 is reached, and which conditions would apply on entry (e.g. maybe they will require visitors to self-isolate for a time after entering the country, or visitors will be rejected if they fail a medical test). Or it is even entirely possible that by the end of July this de-escalation schema has already been changed to something else.