add WEAKDEPS to trigger package extensions (#5026)

PlotsBase/src/PlotsBase.jl

@@ -7,6 +7,16 @@ if isdefined(Base, :Experimental) && isdefined(Base.Experimental, Symbol("@max_m
     @eval Base.Experimental.@max_methods 1
 end
 
+# multiple weakdeps triggers (keep in sync with Project.toml !)
+const WEAKDEPS = Expr(
+    :block,
+    :(import UnitfulLatexify),
+    :(import LaTeXStrings),
+    :(import Latexify),
+    :(import Contour),
+    :(import Colors),
+)
+
 using Base.Meta
 
 import PrecompileTools

PlotsBase/src/backends.jl

@@ -15,6 +15,8 @@ for sym ∈ _default_supported_syms
     end
 end
 
+const WEAKDEPS = 
+
 _display(::Plot{NoneBackend}) =
     @warn "No backend activated yet. Load the backend library and call the activation function to do so.\nE.g. `import GR; gr()` activates the GR backend."
 

PlotsBase/test/runtests.jl

@@ -14,17 +14,7 @@ const TEST_BACKENDS = NamedTuple(p => Symbol(lowercase(string(p))) for p ∈ TES
 get!(ENV, "MPLBACKEND", "agg")
 
 using PlotsBase
-
-# multiple weakdeps (keep in sync with Project.toml !)
-const WEAKDEPS = Expr(
-    :block,
-    :(import UnitfulLatexify),
-    :(import LaTeXStrings),
-    :(import Latexify),
-    :(import Contour),
-    :(import Colors),
-)
-eval(WEAKDEPS)
+eval(PlotsBase.WEAKDEPS)
 
 # initialize all backends
 for pkg ∈ TEST_PACKAGES

PlotsBase/test/test_preferences.jl

@@ -72,7 +72,7 @@ end
         write(
             script,
             """
-            $WEAKDEPS
+            $(PlotsBase.WEAKDEPS)
 
             import $pkg
             using Test, PlotsBase

docs/make.jl

@@ -23,6 +23,7 @@ import UnicodePlots
 import StatsPlots
 
 const PlotsBase = Plots.PlotsBase
+eval(PlotsBase.WEAKDEPS)
 
 const SRC_DIR = joinpath(@__DIR__, "src")
 const WORK_DIR = joinpath(@__DIR__, "work")