[humble] Allow to specify start offset from CLI arguments equal to 0.…

…0 for the rosbag2 player (backport #1682) (#1715)

* fix(start-offset): allow specifying a start offset of 0 (#1682)

Signed-off-by: Rein Appeldoorn <[email protected]>
(cherry picked from commit 8297cb0)

# Conflicts:
#	ros2bag/ros2bag/verb/burst.py

* Resolve merge conflicts. Delete "burst.py". Humble doesn't have it.

Signed-off-by: Michael Orlov <[email protected]>

---------

Signed-off-by: Michael Orlov <[email protected]>
Co-authored-by: Rein Appeldoorn <[email protected]>
Co-authored-by: Michael Orlov <[email protected]>

ros2bag/ros2bag/api/__init__.py

@@ -100,6 +100,17 @@ def check_positive_float(value: Any) -> float:
         raise ArgumentTypeError('{} is not the valid type (float)'.format(value))
 
 
+def check_not_negative_float(value: Any) -> float:
+    """Argparse validator to verify that a value is a float and that not negative."""
+    try:
+        fvalue = float(value)
+        if fvalue < 0.0:
+            raise ArgumentTypeError(f'Value {value} is less than zero.')
+        return fvalue
+    except ValueError:
+        raise ArgumentTypeError('{} is not the valid type (float)'.format(value))
+
+
 def check_path_exists(value: Any) -> str:
     """Argparse validator to verify a path exists."""
     try:

ros2bag/ros2bag/verb/play.py

@@ -16,6 +16,7 @@
 
 from rclpy.qos import InvalidQoSProfileException
 from ros2bag.api import add_standard_reader_args
+from ros2bag.api import check_not_negative_float
 from ros2bag.api import check_not_negative_int
 from ros2bag.api import check_positive_float
 from ros2bag.api import convert_yaml_to_qos_profile
@@ -85,7 +86,7 @@ def add_arguments(self, parser, cli_name):  # noqa: D102
             '-p', '--start-paused', action='store_true', default=False,
             help='Start the playback player in a paused state.')
         parser.add_argument(
-            '--start-offset', type=check_positive_float, default=0.0,
+            '--start-offset', type=check_not_negative_float, default=0.0,
             help='Start the playback player this many seconds into the bag file.')
         parser.add_argument(
             '--wait-for-all-acked', type=check_not_negative_int, default=-1,