Support augment_platform in BB

Author: vchuravy

src/AutoBuild.jl

@@ -140,10 +140,18 @@ supported ones. A few additional keyword arguments are accept:
   package. This can for example be used to invoke an initialization API of a
   shared library.
 
+* `augment_platform_block` may be set to a string containing Julia code; if
+  present, this code will be inserted into the top-level of the
+  generated JLL package. It must define a function `augment_platform!` that takes
+  as a single argument, the target platform and returns the target platform, with
+  amended tags. This augmented platform will then be used by the JLL wrapper to select
+  the artifact.
+
 !!! note
 
-    The `init_block` keyword argument is experimental and may be removed
-    in a future version of this package. Please use it sparingly.
+    The `init_block` and `augment_platform_block` keyword arguments are experimental
+    and may be removed in a future version of this package. Please use it sparingly.
+
 """
 function build_tarballs(ARGS, src_name, src_version, sources, script,
                         platforms, products, dependencies;
@@ -304,7 +312,7 @@ function build_tarballs(ARGS, src_name, src_version, sources, script,
         # Dependencies that must be downloaded
         dependencies,
     )
-    extra_kwargs = extract_kwargs(kwargs, (:lazy_artifacts, :init_block))
+    extra_kwargs = extract_kwargs(kwargs, (:lazy_artifacts, :init_block, :augment_platform_block))
 
     if meta_json_stream !== nothing
         # If they've asked for the JSON metadata, by all means, give it to them!
@@ -596,7 +604,8 @@ function get_meta_json(
                    dependencies::Vector{<:AbstractDependency};
                    julia_compat::String = DEFAULT_JULIA_VERSION_SPEC,
                    lazy_artifacts::Bool = false,
-                   init_block::String = "")
+                   init_block::String = "",
+                   augment_platform_block::String = "")
 
     dict = Dict(
         "name" => src_name,
@@ -608,6 +617,7 @@ function get_meta_json(
         "julia_compat" => julia_compat,
         "lazy_artifacts" => lazy_artifacts,
         "init_block" => init_block,
+        "augment_platform_block" => augment_platform_block,
     )
     # Do not write the list of platforms when building only for `AnyPlatform`
     if platforms != [AnyPlatform()]
@@ -1063,6 +1073,7 @@ function rebuild_jll_package(obj::Dict;
         lazy_artifacts = lazy_artifacts,
         julia_compat = get(obj, "julia_compat", DEFAULT_JULIA_VERSION_SPEC),
         init_block = get(obj, "init_block", ""),
+        augment_platform_block = get(obj, "augment_platform_block", ""),
         from_scratch = from_scratch,
     )
 end
@@ -1167,7 +1178,8 @@ function build_jll_package(src_name::String,
                            verbose::Bool = false,
                            julia_compat::String = DEFAULT_JULIA_VERSION_SPEC,
                            lazy_artifacts::Bool = false,
-                           init_block = "")
+                           init_block = "",
+                           augment_platform_block = "",)
     # Make way, for prince artifacti
     mkpath(joinpath(code_dir, "src", "wrappers"))
 
@@ -1290,6 +1302,36 @@ function build_jll_package(src_name::String,
         end
     end
 
+    if !isempty(augment_platform_block)
+        pkg_dir = joinpath(code_dir, ".pkg")
+        !ispath(pkg_dir) && mkdir(pkg_dir)
+        open(joinpath(pkg_dir, "platform_augmentation.jl"), "w") do io
+            println(io, """
+            $(augment_platform_block)
+            """)
+        end
+
+        open(joinpath(pkg_dir, "select_artifacts.jl"), "w") do io
+            println(io, """
+            using TOML, Artifacts, Base.BinaryPlatforms
+            include("./platform_augmentation.jl")
+            artifacts_toml = joinpath(dirname(@__DIR__), "Artifacts.toml")
+
+            # Get "target triplet" from ARGS, if given (defaulting to the host triplet otherwise)
+            target_triplet = get(ARGS, 1, Base.BinaryPlatforms.host_triplet())
+
+            # Augment this platform object with any special tags we require
+            platform = augment_platform!(HostPlatform(parse(Platform, target_triplet)))
+
+            # Select all downloadable artifacts that match that platform
+            artifacts = select_downloadable_artifacts(artifacts_toml; platform)
+
+            #Output the result to `stdout` as a TOML dictionary
+            TOML.print(stdout, artifacts)
+            """)
+        end
+    end
+
     # Generate target-demuxing main source file.
     open(joinpath(code_dir, "src", "$(src_name)_jll.jl"), "w") do io
         print(io, """
@@ -1301,6 +1343,14 @@ function build_jll_package(src_name::String,
         if lazy_artifacts
             println(io, "using LazyArtifacts")
         end
+
+        if !isempty(augment_platform_block)
+            print(io, """
+            include(path) = Base.include(@__MODULE__, path)
+            include(joinpath("..", ".pkg", "platform_augmentation.jl"))
+            """)
+        end
+
         print(io, """
         import JLLWrappers
 
@@ -1503,7 +1553,7 @@ function build_project_dict(name, version, dependencies::Array{Dependency}, juli
         "deps" => Dict{String,Any}(),
         # We require at least Julia 1.3+, for Pkg.Artifacts support, but we only claim
         # Julia 1.0+ by default so that empty JLLs can be installed on older versions.
-        "compat" => Dict{String,Any}("JLLWrappers" => "1.2.0",
+        "compat" => Dict{String,Any}("JLLWrappers" => "1.4.0",
                                      "julia" => "$(julia_compat)")
     )
 

test/basic.jl

@@ -199,7 +199,7 @@ end
     @test dict["name"] == "$(name)_jll"
     @test dict["version"] == "1.0.0"
     @test dict["uuid"] == "8fcd9439-76b0-55f4-a525-bad0597c05d8"
-    @test dict["compat"] == Dict{String,Any}("julia" => "1.0", "JLLWrappers" => "1.2.0")
+    @test dict["compat"] == Dict{String,Any}("julia" => "1.0", "JLLWrappers" => "1.4.0")
     @test all(in.(
         (
             "Pkg"       => "44cfe95a-1eb2-52ea-b672-e2afdf69b78f",
@@ -224,10 +224,10 @@ end
 
     # Ensure passing a Julia dependency bound works
     dict = build_project_dict(name, version, dependencies, "1.4")
-    @test dict["compat"] == Dict{String,Any}("julia" => "1.4", "JLLWrappers" => "1.2.0")
+    @test dict["compat"] == Dict{String,Any}("julia" => "1.4", "JLLWrappers" => "1.4.0")
 
     dict = build_project_dict(name, version, dependencies, "~1.4")
-    @test dict["compat"] == Dict{String,Any}("julia" => "~1.4", "JLLWrappers" => "1.2.0")
+    @test dict["compat"] == Dict{String,Any}("julia" => "~1.4", "JLLWrappers" => "1.4.0")
 
     @test_throws ErrorException build_project_dict(name, version, dependencies, "nonsense")
 

test/jll.jl

@@ -24,7 +24,7 @@ module TestJLL end
                                   "Scratch"     => "6c6a2e73-6563-6170-7368-637461726353")
     @test project["name"] == "LibFoo_jll"
     @test project["uuid"] == "b250f842-3251-58d3-8ee4-9a24ab2bab3f"
-    @test project["compat"] == Dict("julia" => "1.0", "XZ_jll" => "=2.4.6", "JLLWrappers" => "1.2.0")
+    @test project["compat"] == Dict("julia" => "1.0", "XZ_jll" => "=2.4.6", "JLLWrappers" => "1.4.0")
     @test project["version"] == "1.3.5"
     # Make sure BuildDependency's don't find their way to the project
     @test_throws MethodError build_project_dict("LibFoo", v"1.3.5", [Dependency("Zlib_jll"), BuildDependency("Xorg_util_macros_jll")])