pyproj/geod.py - set return_back_azimuth: Optional[bool] = None to …

…emit warning for the braking change for [fwd|inv]_intermediate

pyproj/geod.py

@@ -17,6 +17,7 @@
 ]
 
 import math
+import warnings
 from typing import Any, Dict, List, Optional, Tuple, Union
 
 from pyproj._geod import Geod as _Geod
@@ -328,6 +329,7 @@ def inv(
         return_back_azimuth: bool = True,
     ) -> Tuple[Any, Any, Any]:
         """
+
         Inverse transformation
 
         Determine forward and back azimuths, plus distances
@@ -521,7 +523,7 @@ def inv_intermediate(
         out_lons: Optional[Any] = None,
         out_lats: Optional[Any] = None,
         out_azis: Optional[Any] = None,
-        return_back_azimuth: bool = True,
+        return_back_azimuth: Optional[bool] = None,
     ) -> GeodIntermediateReturn:
         """
         .. versionadded:: 3.1.0
@@ -643,6 +645,15 @@ def inv_intermediate(
         GeodIntermediateReturn:
             number of points, distance and output arrays (GeodIntermediateReturn docs)
         """
+        if return_back_azimuth is None:
+            return_back_azimuth = True
+            warnings.warn(
+                "Back azimuth is being returned by default to be compatible with fwd()"
+                "This is a breaking change for pyproj 3.5+."
+                "To avoid this warning, set return_back_azimuth=True."
+                "Otherwise, to restore old behaviour, set return_back_azimuth=False."
+                "This warning will be removed in future version."
+            )
         return super()._inv_or_fwd_intermediate(
             lon1=lon1,
             lat1=lat1,
@@ -674,7 +685,7 @@ def fwd_intermediate(
         out_lons: Optional[Any] = None,
         out_lats: Optional[Any] = None,
         out_azis: Optional[Any] = None,
-        return_back_azimuth: bool = True,
+        return_back_azimuth: Optional[bool] = None,
     ) -> GeodIntermediateReturn:
         """
         .. versionadded:: 3.1.0
@@ -781,6 +792,15 @@ def fwd_intermediate(
         GeodIntermediateReturn:
             number of points, distance and output arrays (GeodIntermediateReturn docs)
         """
+        if return_back_azimuth is None:
+            return_back_azimuth = True
+            warnings.warn(
+                "Back azimuth is being returned by default to be compatible with inv()"
+                "This is a breaking change for pyproj 3.5+."
+                "To avoid this warning, set return_back_azimuth=True."
+                "Otherwise, to restore old behaviour, set return_back_azimuth=False."
+                "This warning will be removed in future version."
+            )
         return super()._inv_or_fwd_intermediate(
             lon1=lon1,
             lat1=lat1,