Fixes #1338

[Mattriks]

• I've added and/or updated the unit tests
• I've run the regression tests
• I've built the docs and confirmed these changes don't cause new errors

This PR:

• Fixes shape does not properly work with layers #1338
• Makes the default behaviour for Geom.point consistent with the other discrete aesthetics
• Makes the syntax e.g. shape=x, when length(x)==1, work with Geom.subplot_grid

Examples

# p2 and p3 refer to the 2nd and 3rd plot in #1338
y = rand(10)
df = DataFrame(x=repeat(1:5,2), y=y, z=repeat(["a","b"], inner=5))
stylef(shape::Function) = style(point_shapes=[shape], point_size=2mm)

p2 = plot( layer(x=1:10, y=y, stylef(Shape.cross)),
    layer(x=1:10, y=y.+0.3, stylef(Shape.xcross)) )
p3 = plot(df, xgroup=:z, x=:x, y=:y, shape=[Shape.square], alpha=[0.1],
    Geom.subplot_grid(Geom.point), 
    Theme(point_size=5pt, key_position=:none, discrete_highlight_color=identity)
)
hstack(p2, p3)

[Mattriks]

Looks like Gadfly's Cairo compatibility needs to be updated (due to GiovineItalia/Compose.jl#360). Does someone want to do that in a separate PR? Note that Cairo.jl is currently on v0.8.

[CiaranOMara]

@Mattriks, the merge of GiovineItalia/Compose.jl#360 has not yet been released. Both Compose.jl and Gadfly.jl need to be updated.

[Mattriks]

For Gadfly, Travis uses Compose#master, which is why the tests currently fail here. Do you want to start PRs updating to Cairo v0.8 for Compose and Gadfly?

[CiaranOMara]

Yeah, alright.

[Mattriks]

Bump. This PR is ready to merge.

[bjarthur]

tests fail because of Cairo. we need this put into a separate PR first.

[codecov-io]

Codecov Report

Merging #1339 into master will increase coverage by 0.02%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1339      +/-   ##
==========================================
+ Coverage   90.12%   90.15%   +0.02%     
==========================================
  Files          36       36              
  Lines        3940     3940              
==========================================
+ Hits         3551     3552       +1     
+ Misses        389      388       -1

Impacted Files	Coverage Δ
src/aesthetics.jl	81.89% <100%> (+0.86%)	⬆️
src/geom/point.jl	100% <100%> (ø)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update d4abe78...43ca816. Read the comment docs.

[Mattriks]

Done.