update error messages

Author: mashehu

nf_core/components/components_test.py

@@ -208,13 +208,12 @@ def generate_snapshot(self) -> bool:
             obsolete_snapshots = compiled_pattern.search(nftest_out.decode())
             if obsolete_snapshots:
                 self.obsolete_snapshots = True
-
             # check if nf-test was successful
             if "Assertion failed:" in nftest_out.decode():
                 return False
-            elif "no valid tests found." in nftest_out.decode():
-                log.error("Test file 'main.nf.test' not found")
-                self.errors.append("Test file 'main.nf.test' not found")
+            elif "No tests to execute." in nftest_out.decode():
+                log.error("Nothing to execute. Is the file 'main.nf.test' missing?")
+                self.errors.append("Nothing to execute. Is the file 'main.nf.test' missing?")
                 return False
             else:
                 log.debug("nf-test successful")

tests/components/test_components_generate_snapshot.py

@@ -136,5 +136,5 @@ def test_test_not_found(self):
             test_file.rename(test_file.parent / "main.nf.test.bak")
             with pytest.raises(UserWarning) as e:
                 snap_generator.run()
-            assert "No tests to execute." in str(e.value)
+            assert "Nothing to execute. Is the file 'main.nf.test' missing?" in str(e.value)
             Path(test_file.parent / "main.nf.test.bak").rename(test_file)