Update implementation

Author: eliascarv

src/georef.jl

@@ -37,7 +37,7 @@ Georeference `table` using coordinates `coords` of points.
 
 Optionally, specify the coordinate reference system `crs`, which is
 set by default based on heuristics, and the `lenunit` (default to meters for unitless values)
-that will be used in CRS types that allow this flexibility. Any `CRS` or `EPSG`/`ESRI` 
+that can only be used in CRS types that allow this flexibility. Any `CRS` or `EPSG`/`ESRI` 
 code from [CoordRefSystems.jl](https://github.com/JuliaEarth/CoordRefSystems.jl)
 is supported.
 
@@ -65,7 +65,7 @@ Georeference `table` using coordinates of points stored in column `names`.
 
 Optionally, specify the coordinate reference system `crs`, which is
 set by default based on heuristics, and the `lenunit` (default to meters for unitless values)
-that will be used in CRS types that allow this flexibility. Any `CRS` or `EPSG`/`ESRI` 
+that can only be used in CRS types that allow this flexibility. Any `CRS` or `EPSG`/`ESRI` 
 code from [CoordRefSystems.jl](https://github.com/JuliaEarth/CoordRefSystems.jl)
 is supported.
 
@@ -170,7 +170,7 @@ function pointbuilder(crs, u)
     elseif crs <: Spherical
       (r, θ, ϕ) -> Point(crs(withunit(r, u), withunit(θ, u"rad"), withunit(ϕ, u"rad")))
     else
-      (coords...) -> Point(crs(coords...))
+      throw(ArgumentError("the length unit of CRS `$crs` cannot be changed"))
     end
   end
 end

test/georef.jl

@@ -153,9 +153,7 @@
   gtb = georef(table, ("x", "y"), lenunit=u"m")
   @test crs(gtb.geometry) <: Cartesian
   @test unit(Meshes.lentype(gtb.geometry)) == u"m"
-  # `lenunit` option only affects Basic CRS
+  # error: the length unit of CRS `LatLon` cannot be changed
   table = (a=rand(10), lat=rand(10), lon=rand(10))
-  gtb = georef(table, ("lat", "lon"), crs=LatLon, lenunit=u"km")
-  @test crs(gtb.geometry) <: LatLon
-  @test unit(Meshes.lentype(gtb.geometry)) == u"m"
+  @test_throws ArgumentError georef(table, ("lat", "lon"), crs=LatLon, lenunit=u"km")
 end