... when gradient_type >= GIMP_GRADIENT_SHAPEBURST_ANGULAR.
Our current GUI code for the Blend tool options disables the "Repeat"
widget with any of the shaped and spiral gradient types, which means (I
assume) no repeat mode is allowed on these gradients. Nevertheless it
was possible to change the repeat mode in another gradient type, then
switch to one of these and get the repeat processed even though the GUI
shows insensitive.
I could simply reset the repeat mode to GIMP_REPEAT_NONE when setting
one of these gradient types, but I think you'd want the repeat to stay
at its value (being insensitive is enough to mean whatever value is set
is not taken into account). So instead, I just unsync this specific
property when appropriate.
Note also I don't do this in the gimp:blend operation code because I am
not sure this specific behavior is meant to be a generic blend behavior
or just relative to the tool (render of the shaped gradients is barely
different with a repeat, but there is still a difference).