i am inside the IDE and i can run all the unit tests in a file but is there any way to run all test in a project or solution at once?
Open ReSharper->Windows->Unit Test Explorer and select everything, then hit the run button
Right click on the project or solution in the VS solution-explorer and choose 'Run Unit Tests' Or go to the Resharper menu, choose Unit-Testing and choose one of the options from there.
If you learn executing menu commands with Alt-Letters, you can execute many commands fast even if they don't have direct shortcuts. Especially, if shortcuts are two-key combos.
As for running all tests in solution the command is Alt-RUN, i.e. Alt-R for ReSharper menu, U for Unit Testing, and N for all tests in solution.
I'm surprised no one mentioned it here, but pretty much all resharper commands can be assigned to specific custom keyboard shortcuts. Go to Tools --> Options --> Keyboard
, and find the command you're interested (just type "resharper" in the "show commands containing" text field & you'll find them all). In this specific instance, the "Run All Tests from Solution" command is "ReSharper.UnitTest_RunSolution".