work out line shape for ecdfmode

Author: nicolaskruchten

Diff for: packages/python/plotly/plotly/express/_chart_types.py

@@ -519,7 +519,6 @@ def ecdf(
     marginal=None,
     opacity=None,
     orientation=None,
-    line_shape="hv",
     ecdfnorm="probability",
     ecdfmode="standard",
     render_mode="auto",

Diff for: packages/python/plotly/plotly/express/_core.py

@@ -1825,6 +1825,10 @@ def infer_config(args, constructor, trace_patch, layout_patch):
 
     if "line_shape" in args:
         trace_patch["line"] = dict(shape=args["line_shape"])
+    elif "ecdfmode" in args:
+        trace_patch["line"] = dict(
+            shape="vh" if args["ecdfmode"] == "reversed" else "hv"
+        )
 
     if "geojson" in args:
         trace_patch["featureidkey"] = args["featureidkey"]