Machine-specific test failures

[Cody-G]

See JuliaImages/ImageView.jl#141 for context. All Gtk.jl tests pass, but several of the canvas-related tests of GtkReactive.jl are failing on one of our machines. Curiously, julia package versions, OS (Ubuntu 17.10), and GTK libraries appear to match another of our machines that passes tests. Here is the test output:

julia> Pkg.test("GtkReactive")
INFO: Computing test dependencies for GtkReactive...
INFO: No packages to install, update or remove
INFO: Testing GtkReactive
Test Summary: | Pass  Total
Widgets       |   63     63
Test Summary:    | Pass  Total
Compound widgets |    3      3
Test Summary: | Pass  Total
CairoUnits    |    9      9
Canvas: Test Failed
  Expression: GtkReactive.convertunits(UserUnit, c, corner_dev...) == corner_usr
   Evaluated: (UserUnit(208.0), UserUnit(207.0)) == (UserUnit(1.0), UserUnit(1.0))
Stacktrace:
 [1] macro expansion at /home/cody/.julia/reg_and_seg/v0.6/GtkReactive/test/runtests.jl:351 [inlined]
 [2] macro expansion at ./test.jl:860 [inlined]
 [3] anonymous at ./<missing>:?
Canvas: Test Failed
  Expression: GtkReactive.convertunits(DeviceUnit, c, corner_usr...) == corner_dev
   Evaluated: (DeviceUnit(1.0), DeviceUnit(1.0)) == (DeviceUnit(208.0), DeviceUnit(207.0))
Stacktrace:
 [1] macro expansion at /home/cody/.julia/reg_and_seg/v0.6/GtkReactive/test/runtests.jl:354 [inlined]
 [2] macro expansion at ./test.jl:860 [inlined]
 [3] anonymous at ./<missing>:?
Canvas: Test Failed
  Expression: GtkReactive.convertunits(UserUnit, c, corner_dev...) == corner_usr
   Evaluated: (UserUnit(208.0), UserUnit(207.0)) == (UserUnit(5.0), UserUnit(10.0))
Stacktrace:
 [1] macro expansion at /home/cody/.julia/reg_and_seg/v0.6/GtkReactive/test/runtests.jl:351 [inlined]
 [2] macro expansion at ./test.jl:860 [inlined]
 [3] anonymous at ./<missing>:?
Canvas: Test Failed
  Expression: GtkReactive.convertunits(DeviceUnit, c, corner_usr...) == corner_dev
   Evaluated: (DeviceUnit(5.0), DeviceUnit(10.0)) == (DeviceUnit(208.0), DeviceUnit(207.0))
Stacktrace:
 [1] macro expansion at /home/cody/.julia/reg_and_seg/v0.6/GtkReactive/test/runtests.jl:354 [inlined]
 [2] macro expansion at ./test.jl:860 [inlined]
 [3] anonymous at ./<missing>:?
Canvas: Test Failed
  Expression: GtkReactive.convertunits(UserUnit, c, corner_dev...) == corner_usr
   Evaluated: (UserUnit(208.0), UserUnit(207.0)) == (UserUnit(110.0), UserUnit(1.0))
Stacktrace:
 [1] macro expansion at /home/cody/.julia/reg_and_seg/v0.6/GtkReactive/test/runtests.jl:351 [inlined]
 [2] macro expansion at ./test.jl:860 [inlined]
 [3] anonymous at ./<missing>:?
Canvas: Test Failed
  Expression: GtkReactive.convertunits(DeviceUnit, c, corner_usr...) == corner_dev
   Evaluated: (DeviceUnit(110.0), DeviceUnit(1.0)) == (DeviceUnit(208.0), DeviceUnit(207.0))
Stacktrace:
 [1] macro expansion at /home/cody/.julia/reg_and_seg/v0.6/GtkReactive/test/runtests.jl:354 [inlined]
 [2] macro expansion at ./test.jl:860 [inlined]
 [3] anonymous at ./<missing>:?
Test Summary: | Pass  Fail  Total
Canvas        |   23     6     29
ERROR: LoadError: Some tests did not pass: 23 passed, 6 failed, 0 errored, 0 broken.
while loading /home/cody/.julia/reg_and_seg/v0.6/GtkReactive/test/runtests.jl, in expression starting on line 318
================================================================[ ERROR: GtkReactive ]=================================================================

failed process: Process(`/home/cody/src/julia_06/usr/bin/julia -Cnative -J/home/cody/src/julia_06/usr/lib/julia/sys.so --compile=yes --depwarn=yes --check-bounds=yes --code-coverage=none --color=yes --compilecache=yes /home/cody/.julia/reg_and_seg/v0.6/GtkReactive/test/runtests.jl`, ProcessExited(1)) [1]

=======================================================================================================================================================
INFO: Removing ImageMagick v0.5.0
INFO: Removing TestImages v0.2.0
INFO: Removing ZipFile v0.5.0
ERROR: GtkReactive had test errors

[Cody-G]

Actually I realized one package version was mismatched with the good machine: Cairo. v0.4.0 works well, so I've pinned my machine there. FYI that version was recently suggested for another reason: JuliaImages/ImageView.jl#139