Ensure project is not empty when starting a new frame

Fix jazzband#321

CHANGELOG.md

@@ -15,6 +15,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Stylize prompt to create new project or tag (#310).
 - Aggregate calculates wrong time if used with `--current` (#293)
+- The `start` command now correctly checks if project is empty (#322)
 
 ## [1.8.0] - 2019-08-26
 

watson/cli.py

@@ -205,6 +205,8 @@ def start(ctx, watson, confirm_new_project, confirm_new_tag, args, gap_=True):
     project = ' '.join(
         itertools.takewhile(lambda s: not s.startswith('+'), args)
     )
+    if not project:
+        raise click.ClickException("No project given.")
 
     # Confirm creation of new project if that option is set
     if (watson.config.getboolean('options', 'confirm_new_project') or
@@ -1143,6 +1145,8 @@ def add(watson, args, from_, to, confirm_new_project, confirm_new_tag):
     project = ' '.join(
         itertools.takewhile(lambda s: not s.startswith('+'), args)
     )
+    if not project:
+        raise click.ClickException("No project given.")
 
     # Confirm creation of new project if that option is set
     if (watson.config.getboolean('options', 'confirm_new_project') or

watson/watson.py

@@ -252,9 +252,6 @@ def add(self, project, from_date, to_date, tags):
         return frame
 
     def start(self, project, tags=None, restart=False, gap=True):
-        if not project:
-            raise WatsonError("No project given.")
-
         if self.is_started:
             raise WatsonError(
                 u"Project {} is already started.".format(