Fix the buffer error hinter (#163)

* Fix the buffer error hinter

* Update buffer.jl

src/methods/buffer.jl

@@ -16,12 +16,12 @@ end
 # which checks if there is a method error for the geos backend.
 
 
-# Add an error hint for GeodesicSegments if Proj is not loaded!
+# Add an error hint for `buffer` if LibGEOS is not loaded!
 function _buffer_error_hinter(io, exc, argtypes, kwargs)
-    if isnothing(Base.get_extension(GeometryOps, :GeometryOpsLibGEOSExt)) && exc.f == buffer && first(exc.argtypes) == GEOS
+    if isnothing(Base.get_extension(GeometryOps, :GeometryOpsLibGEOSExt)) && exc.f == buffer && first(argtypes) == GEOS
         print(io, "\n\nThe `buffer` method requires the LibGEOS.jl package to be explicitly loaded.\n")
         print(io, "You can do this by simply typing ")
         printstyled(io, "using LibGEOS"; color = :cyan, bold = true)
         println(io, " in your REPL, \nor otherwise loading LibGEOS.jl via using or import.")
     end
-end
+end