"Emmanuel Macron, the French president, has announced that he is dissolving the national assembly, and calling for legislative elections on June 30 and July 7.
The French president said that he can’t pretend nothing has happened, that the outcome of the EU election is not good for his government and that the rise of nationalists is a danger for France and Europe."
“dissolving parliament” means they’ve announced a general election. Parliament won’t meet any more, and all the existing members of parliament will go home and begin campaigning
The UK is going through the same thing. The Prime Minister dissolved Parliament about two weeks ago, and elections are going to be held of July 4th. (An odd choice, but apparently elections are always on a Thursday in the UK.)