Created attachment 289754 [details] [review]
Patch to type-check GIMP-PDB-COLOR arguments

Description:

When passing arguments of type GIMP_PDB_COLOR to PDB procedures (such as 'gimp-context-set-foreground'), the color specification should be either a string containing a CSS color or a list of three numbers (for the red, green, and blue components). Script-fu properly tests that the argument is either a string or a 3-element list but in the case of a list, it does not verify that the elements of the list are numbers. 


Steps to Reproduce:

  1) Open the Script-fu console
  2) Enter the command: 
    (gimp-context-set-foreground '(x y z))

Result:

  The foreground color gets set to white. Apparently the memory address of the symbols are treated as the list elements (and gets clamped to "255").

Expected result:

  Script-fu should detect that the list argument contains non-numbers and should generate an error.


Note:

  Current behavior does not interfere with proper functioning of valid scripts. It is only that errors that should be detected are not.

  Attached patch was made against GIMP 2.8.14. I am not sure if the error message sent during DEBUG_MARSHALL output is sufficient. It currently sends "COLOR list contains non-numbers" but does not echo the offending argument (to do so would require converting the Scheme expression to a string).