JuliaLang · IanButterworth · Nov 23, 2022 · Nov 27, 2022 · Nov 27, 2022 · Nov 29, 2022
diff --git a/NEWS.md b/NEWS.md
@@ -4,7 +4,11 @@ Julia v1.10 Release Notes
 New language features
 ---------------------
 
-
+New feature for packages that allows loading a piece of code based on other
+packages being loaded in the Julia session.
+This has similar applications as the Requires.jl package but also
+supports precompilation and setting compatibility.
+Look in the documentation for Pkg.jl for "glue packages" for more information.
 Language changes
 ----------------
 

diff --git a/base/loading.jl b/base/loading.jl
diff --git a/base/sysimg.jl b/base/sysimg.jl
@@ -59,7 +59,6 @@ let
         :InteractiveUtils,
         :LibGit2,
         :Profile,
-        :SparseArrays,
         :UUIDs,
 
         # 3-depth packages

diff --git a/deps/checksums/Pkg-ed6a5497e46ed541b2718c404c0f468b7f92263a.tar.gz/md5 b/deps/checksums/Pkg-ed6a5497e46ed541b2718c404c0f468b7f92263a.tar.gz/md5
diff --git a/deps/checksums/Pkg-ed6a5497e46ed541b2718c404c0f468b7f92263a.tar.gz/sha512 b/deps/checksums/Pkg-ed6a5497e46ed541b2718c404c0f468b7f92263a.tar.gz/sha512
diff --git a/deps/checksums/Pkg-f1a47ed18bd3a306e318143befe9466a5f5fd571.tar.gz/md5 b/deps/checksums/Pkg-f1a47ed18bd3a306e318143befe9466a5f5fd571.tar.gz/md5
@@ -0,0 +1 @@
+bd49ed22b9fa0f86885d26265cc09161
diff --git a/deps/checksums/Pkg-f1a47ed18bd3a306e318143befe9466a5f5fd571.tar.gz/sha512 b/deps/checksums/Pkg-f1a47ed18bd3a306e318143befe9466a5f5fd571.tar.gz/sha512
@@ -0,0 +1 @@
+c531b521fa0976f8c155d06c226824b65e3542f0c06e0b0fcb4052e6027f1baf749566e0191f8a83ab0a13165825447f71474d3685b282ffbf3e270a64e21c17
diff --git a/doc/src/manual/code-loading.md b/doc/src/manual/code-loading.md
@@ -348,7 +348,46 @@ The subscripted `rootsᵢ`, `graphᵢ` and `pathsᵢ` variables correspond to th
 2. Packages in non-primary environments can end up using incompatible versions of their dependencies even if their own environments are entirely compatible. This can happen when one of their dependencies is shadowed by a version in an earlier environment in the stack (either by graph or path, or both).
 
 Since the primary environment is typically the environment of a project you're working on, while environments later in the stack contain additional tools, this is the right trade-off: it's better to break your development tools but keep the project working. When such incompatibilities occur, you'll typically want to upgrade your dev tools to versions that are compatible with the main project.
+### "Glue" packages and dependencies
 
+A "glue package" is a module that is automatically loaded when a specified set of other packages (its "glue dependencies") are loaded in the current Julia session. The glue dependencies of a glue package is a subset of those packages listed under the `[weakdeps]` section of a Project file. Glue packages are defined under the `[gluepkgs]` section in the project file:
+
+```toml
+name = "MyPackage"
+
+[weakdeps]
+GlueDep = "c9a23..." # uuid
+OtherGlueDep = "862e..." # uuid
+
+[gluepkgs]
+GlueBar = ["GlueDep", "OtherGlueDep"]
+GlueFoo = "GlueDep"
+...
+```
+
+The keys under `gluepkgs` are the name of the glue packages.
+They are loaded when all the packages on the right hand side (the glue dependencies) of that glue package are loaded.
+If a glue package only has one glue dependency the list of glue dependencies can be written as just a string for brevity.
+The location for the entry point of the glue package is either in `glue/GlueFoo.jl` or `glue/GlueFoo/GlueFoo.jl` for
+glue package `GlueFoo`.
+The content of a glue package is often structured as:
+
+```
+module GlueFoo
+
+# Load main package and glue dependencies
+using MyPackage, GlueDep
+
+# Extend functionality in main package with types from the glue dependencies
+MyPackage.func(x::GlueDep.SomeStruct) = ...
+
+end
+```
+
+When a package with glue packages is added to an environment, the `weakdeps` and `gluepkgs` sections
+are stored in the manifest file in the section for that package. The dependency lookup rules for
+a package are the same as for its "parent" except that the listed glue dependencies are also considered as
+dependencies.
 ### Package/Environment Preferences
 
 Preferences are dictionaries of metadata that influence package behavior within an environment.

diff --git a/stdlib/Pkg.version b/stdlib/Pkg.version
@@ -1,4 +1,4 @@
 PKG_BRANCH = master
-PKG_SHA1 = ed6a5497e46ed541b2718c404c0f468b7f92263a
+PKG_SHA1 = f1a47ed18bd3a306e318143befe9466a5f5fd571
 PKG_GIT_URL := https://github.com/JuliaLang/Pkg.jl.git
 PKG_TAR_URL = https://api.github.com/repos/JuliaLang/Pkg.jl/tarball/$1
diff --git a/stdlib/Statistics.version b/stdlib/Statistics.version
@@ -1,4 +1,4 @@
-STATISTICS_BRANCH = master
-STATISTICS_SHA1 = 20fbe576ec406180b1dddf4c7fbe16458a7aef21
-STATISTICS_GIT_URL := https://github.com/JuliaStats/Statistics.jl.git
-STATISTICS_TAR_URL = https://api.github.com/repos/JuliaStats/Statistics.jl/tarball/$1
+STATISTICS_BRANCH = ib/glue
+STATISTICS_SHA1 = 86454ce6e8f6dc11e548921be8522d790dc1ea86
+STATISTICS_GIT_URL := https://github.com/IanButterworth/Statistics.jl.git
+STATISTICS_TAR_URL = https://api.github.com/repos/IanButterworth/Statistics.jl/tarball/$1
diff --git a/test/loading.jl b/test/loading.jl
@@ -991,5 +991,37 @@ end
     end
 end
 
+
+@testset "GluePkgs" begin
+    old_depot_path = copy(DEPOT_PATH)
+    try
+        tmp = mktempdir()
+        push!(empty!(DEPOT_PATH), joinpath(tmp, "depot"))
+
+        proj = joinpath(@__DIR__, "project", "GluePkgs", "HasDepWithGluePkgs.jl")
+        for i in 1:2 # Once when requiring precomilation, once where it is already precompiled
+            cmd = `$(Base.julia_cmd()) --project=$proj --startup-file=no -e '
+                begin
+                using HasGluePkgs
+                Base.get_gluepkg(HasGluePkgs, :GluePkg) === nothing || error("unexpectedly got a glue module")
+                HasGluePkgs.glue_loaded && error("glue_loaded set")
+                using HasDepWithGluePkgs
+                Base.get_gluepkg(HasGluePkgs, :GluePkg).gluevar == 1 || error("gluevar in GluePkg not set")
+                HasGluePkgs.glue_loaded || error("glue_loaded not set")
+                HasGluePkgs.glue_folder_loaded && error("glue_folder_loaded set")
+                HasDepWithGluePkgs.do_something() || error("do_something errored")
+                using GlueDep2
+                HasGluePkgs.glue_folder_loaded || error("glue_folder_loaded not set")
+
+                end
+            '`
+            @test success(cmd)
+        end
+    finally
+        copy!(DEPOT_PATH, old_depot_path)
+    end
+end
+
+
 empty!(Base.DEPOT_PATH)
 append!(Base.DEPOT_PATH, original_depot_path)
diff --git a/test/precompile.jl b/test/precompile.jl
@@ -372,7 +372,7 @@ precompile_test_harness(false) do dir
                  :LazyArtifacts, :LibCURL, :LibCURL_jll, :LibGit2, :Libdl, :LinearAlgebra,
                  :Logging, :Markdown, :Mmap, :MozillaCACerts_jll, :NetworkOptions, :OpenBLAS_jll, :Pkg, :Printf,
                  :Profile, :p7zip_jll, :REPL, :Random, :SHA, :Serialization, :SharedArrays, :Sockets,
-                 :SparseArrays, :TOML, :Tar, :Test, :UUIDs, :Unicode,
+                 :TOML, :Tar, :Test, :UUIDs, :Unicode,
                  :nghttp2_jll]
             ),
         )

diff --git a/test/project/GluePkgs/GlueDep.jl/Project.toml b/test/project/GluePkgs/GlueDep.jl/Project.toml
@@ -0,0 +1,3 @@
+name = "GlueDep"
+uuid = "fa069be4-f60b-4d4c-8b95-f8008775090c"
+version = "0.1.0"
diff --git a/test/project/GluePkgs/GlueDep.jl/src/GlueDep.jl b/test/project/GluePkgs/GlueDep.jl/src/GlueDep.jl
@@ -0,0 +1,5 @@
+module GlueDep
+
+struct GlueDepStruct end
+
+end # module GlueDep
diff --git a/test/project/GluePkgs/GlueDep2/Project.toml b/test/project/GluePkgs/GlueDep2/Project.toml
@@ -0,0 +1,3 @@
+name = "GlueDep2"
+uuid = "55982ee5-2ad5-4c40-8cfe-5e9e1b01500d"
+version = "0.1.0"
diff --git a/test/project/GluePkgs/GlueDep2/src/GlueDep2.jl b/test/project/GluePkgs/GlueDep2/src/GlueDep2.jl
@@ -0,0 +1,5 @@
+module GlueDep2
+
+greet() = print("Hello World!")
+
+end # module GlueDep2
diff --git a/test/project/GluePkgs/HasDepWithGluePkgs.jl/Manifest.toml b/test/project/GluePkgs/HasDepWithGluePkgs.jl/Manifest.toml
@@ -0,0 +1,25 @@
+# This file is machine-generated - editing it directly is not advised
+
+julia_version = "1.10.0-DEV"
+manifest_format = "2.0"
+project_hash = "7cbe1857ecc6692a8cc8be428a5ad5073531ff98"
+
+[[deps.GlueDep]]
+path = "../GlueDep.jl"
+uuid = "fa069be4-f60b-4d4c-8b95-f8008775090c"
+version = "0.1.0"
+
+[[deps.GlueDep2]]
+path = "../GlueDep2"
+uuid = "55982ee5-2ad5-4c40-8cfe-5e9e1b01500d"
+version = "0.1.0"
+
+[[deps.HasGluePkgs]]
+weakdeps = ["GlueDep", "GlueDep2"]
+path = "../HasGluePkgs.jl"
+uuid = "4d3288b3-3afc-4bb6-85f3-489fffe514c8"
+version = "0.1.0"
+
+    [deps.HasGluePkgs.gluepkgs]
+    GluePkg = "GlueDep"
+    GluePkgFolder = ["GlueDep", "GlueDep2"]
diff --git a/test/project/GluePkgs/HasDepWithGluePkgs.jl/Project.toml b/test/project/GluePkgs/HasDepWithGluePkgs.jl/Project.toml
@@ -0,0 +1,8 @@
+name = "HasDepWithGluePkgs"
+uuid = "d4ef3d4a-8e22-4710-85d8-c6cf2eb9efca"
+version = "0.1.0"
+
+[deps]
+GlueDep = "fa069be4-f60b-4d4c-8b95-f8008775090c"
+GlueDep2 = "55982ee5-2ad5-4c40-8cfe-5e9e1b01500d"
+HasGluePkgs = "4d3288b3-3afc-4bb6-85f3-489fffe514c8"
diff --git a/test/project/GluePkgs/HasDepWithGluePkgs.jl/src/HasDepWithGluePkgs.jl b/test/project/GluePkgs/HasDepWithGluePkgs.jl/src/HasDepWithGluePkgs.jl
@@ -0,0 +1,13 @@
+module HasDepWithGluePkgs
+
+using HasGluePkgs: HasGluePkgs, HasGluePkgsStruct
+using GlueDep: GlueDepStruct
+# Loading GlueDep makes the glue module "GluePkg" load
+
+function do_something()
+    HasGluePkgs.foo(HasGluePkgsStruct()) == 1 || error()
+    HasGluePkgs.foo(GlueDepStruct()) == 2 || error()
+    return true
+end
+
+end # module
diff --git a/test/project/GluePkgs/HasGluePkgs.jl/Manifest.toml b/test/project/GluePkgs/HasGluePkgs.jl/Manifest.toml
@@ -0,0 +1,7 @@
+# This file is machine-generated - editing it directly is not advised
+
+julia_version = "1.10.0-DEV"
+manifest_format = "2.0"
+project_hash = "c87947f1f1f070eea848950c304d668a112dec3d"
+
+[deps]
diff --git a/test/project/GluePkgs/HasGluePkgs.jl/Project.toml b/test/project/GluePkgs/HasGluePkgs.jl/Project.toml
@@ -0,0 +1,11 @@
+name = "HasGluePkgs"
+uuid = "4d3288b3-3afc-4bb6-85f3-489fffe514c8"
+version = "0.1.0"
+
+[weakdeps]
+GlueDep = "fa069be4-f60b-4d4c-8b95-f8008775090c"
+GlueDep2 = "55982ee5-2ad5-4c40-8cfe-5e9e1b01500d"
+
+[gluepkgs]
+GluePkg = "GlueDep"
+GluePkgFolder = ["GlueDep", "GlueDep2"]
diff --git a/test/project/GluePkgs/HasGluePkgs.jl/glue/GluePkg.jl b/test/project/GluePkgs/HasGluePkgs.jl/glue/GluePkg.jl
@@ -0,0 +1,13 @@
+module GluePkg
+
+using HasGluePkgs, GlueDep
+
+HasGluePkgs.foo(::GlueDep.GlueDepStruct) = 2
+
+function __init__()
+    HasGluePkgs.glue_loaded = true
+end
+
+const gluevar = 1
+
+end
diff --git a/test/project/GluePkgs/HasGluePkgs.jl/glue/GluePkgFolder/GluePkgFolder.jl b/test/project/GluePkgs/HasGluePkgs.jl/glue/GluePkgFolder/GluePkgFolder.jl
@@ -0,0 +1,9 @@
+module GluePkgFolder
+
+using GlueDep, GlueDep2, HasGluePkgs
+
+function __init__()
+    HasGluePkgs.glue_folder_loaded = true
+end
+
+end
diff --git a/test/project/GluePkgs/HasGluePkgs.jl/src/HasGluePkgs.jl b/test/project/GluePkgs/HasGluePkgs.jl/src/HasGluePkgs.jl
@@ -0,0 +1,10 @@
+module HasGluePkgs
+
+struct HasGluePkgsStruct end
+
+foo(::HasGluePkgsStruct) = 1
+
+glue_loaded = false
+glue_folder_loaded = false
+
+end # module