only load extension triggers from the evnironment where the parent package is loaded

base/loading.jl

@@ -258,7 +258,7 @@ struct LoadingCache
     require_parsed::Set{String}
     identified_where::Dict{Tuple{PkgId, String}, Union{Nothing, Tuple{PkgId, Union{Nothing, String}}}}
     identified::Dict{String, Union{Nothing, Tuple{PkgId, Union{Nothing, String}}}}
-    located::Dict{Tuple{PkgId, Union{String, Nothing}}, Union{String, Nothing}}
+    located::Dict{Tuple{PkgId, Union{String, Nothing}}, Union{Tuple{Union{String, Nothing}, Union{String, Nothing}}, Nothing}}
 end
 const LOADING_CACHE = Ref{Union{LoadingCache, Nothing}}(nothing)
 LoadingCache() = LoadingCache(load_path(), Dict(), Dict(), Dict(), Set(), Dict(), Dict(), Dict())
@@ -390,30 +390,17 @@ identify_package(where::Module, name::String) = _nothing_or_first(identify_packa
 identify_package(where::PkgId, name::String)  = _nothing_or_first(identify_package_env(where, name))
 identify_package(name::String)                = _nothing_or_first(identify_package_env(name))
 
-
-"""
-    Base.locate_package(pkg::PkgId)::Union{String, Nothing}
-
-The path to the entry-point file for the package corresponding to the identifier
-`pkg`, or `nothing` if not found. See also [`identify_package`](@ref).
-
-```julia-repl
-julia> pkg = Base.identify_package("Pkg")
-Pkg [44cfe95a-1eb2-52ea-b672-e2afdf69b78f]
-
-julia> Base.locate_package(pkg)
-"/path/to/julia/stdlib/v$(VERSION.major).$(VERSION.minor)/Pkg/src/Pkg.jl"
-```
-"""
-function locate_package(pkg::PkgId, stopenv::Union{String, Nothing}=nothing)::Union{Nothing,String}
+function locate_package_env(pkg::PkgId, stopenv::Union{String, Nothing}=nothing)
     cache = LOADING_CACHE[]
     if cache !== nothing
-        path = get(cache.located, (pkg, stopenv), nothing)
-        path === nothing || return path
+        pathenv = get(cache.located, (pkg, stopenv), nothing)
+        pathenv === nothing || return pathenv
     end
     path = nothing
+    env′ = nothing
     if pkg.uuid === nothing
         for env in load_path()
+            env′ = env
             # look for the toplevel pkg `pkg.name` in this entry
             found = project_deps_get(env, pkg.name)
             if found !== nothing
@@ -430,6 +417,7 @@ function locate_package(pkg::PkgId, stopenv::Union{String, Nothing}=nothing)::Un
         end
     else
         for env in load_path()
+            env′ = env
             path = manifest_uuid_path(env, pkg)
             # missing is used as a sentinel to stop looking further down in envs
             if path === missing
@@ -452,9 +440,27 @@ function locate_package(pkg::PkgId, stopenv::Union{String, Nothing}=nothing)::Un
     end
     @label done
     if cache !== nothing
-        cache.located[(pkg, stopenv)] = path
+        cache.located[(pkg, stopenv)] = path, env′
     end
-    return path
+    return path, env′
+end
+
+"""
+    Base.locate_package(pkg::PkgId)::Union{String, Nothing}
+
+The path to the entry-point file for the package corresponding to the identifier
+`pkg`, or `nothing` if not found. See also [`identify_package`](@ref).
+
+```julia-repl
+julia> pkg = Base.identify_package("Pkg")
+Pkg [44cfe95a-1eb2-52ea-b672-e2afdf69b78f]
+
+julia> Base.locate_package(pkg)
+"/path/to/julia/stdlib/v$(VERSION.major).$(VERSION.minor)/Pkg/src/Pkg.jl"
+```
+"""
+function locate_package(pkg::PkgId, stopenv::Union{String, Nothing}=nothing)::Union{Nothing,String}
+    _nothing_or_first(locate_package_env(pkg, stopenv))
 end
 
 """
@@ -1108,9 +1114,13 @@ const EXT_DORMITORY_FAILED = ExtensionId[]
 
 function insert_extension_triggers(pkg::PkgId)
     pkg.uuid === nothing && return
-    for env in load_path()
-        insert_extension_triggers(env, pkg)
+    path_env_loc = locate_package_env(pkg)
+    path_env_loc === nothing && return
+    path, env_loc = path_env_loc
+    if path === nothing || env_loc === nothing
+        return
     end
+    insert_extension_triggers(env_loc, pkg)
 end
 
 function insert_extension_triggers(env::String, pkg::PkgId)::Union{Nothing,Missing}

test/loading.jl

@@ -1011,10 +1011,10 @@ end
                 begin
                     push!(empty!(DEPOT_PATH), '$(repr(depot_path))')
                     using HasExtensions
-                    # Base.get_extension(HasExtensions, :Extension) === nothing || error("unexpectedly got an extension")
+                    Base.get_extension(HasExtensions, :Extension) === nothing || error("unexpectedly got an extension")
                     HasExtensions.ext_loaded && error("ext_loaded set")
                     using HasDepWithExtensions
-                    # Base.get_extension(HasExtensions, :Extension).extvar == 1 || error("extvar in Extension not set")
+                    Base.get_extension(HasExtensions, :Extension).extvar == 1 || error("extvar in Extension not set")
                     HasExtensions.ext_loaded || error("ext_loaded not set")
                     HasExtensions.ext_folder_loaded && error("ext_folder_loaded set")
                     HasDepWithExtensions.do_something() || error("do_something errored")
@@ -1032,12 +1032,29 @@ end
             @test success(cmd)
         end
 
-        # 48351
         sep = Sys.iswindows() ? ';' : ':'
+
+        # 48351
         cmd = gen_extension_cmd(``)
         cmd = addenv(cmd, "JULIA_LOAD_PATH" => join([mktempdir(), proj], sep))
         cmd = pipeline(cmd; stdout, stderr)
         @test success(cmd)
+
+        # Only load env from where package is loaded
+        envs = [joinpath(@__DIR__, "project", "Extensions", "EnvWithHasExtensionsv2"), joinpath(@__DIR__, "project", "Extensions", "EnvWithHasExtensions")]
+        cmd = addenv(```$(Base.julia_cmd()) --startup-file=no -e '
+        begin
+
+
+            push!(empty!(DEPOT_PATH), '$(repr(depot_path))')
+            using HasExtensions
+            using ExtDep
+            Base.get_extension(HasExtensions, :Extension) === nothing || error("unexpectedly loaded ext from other env")
+            Base.get_extension(HasExtensions, :Extension2) === nothing && error("did not load ext from active env")
+        end
+        '
+        ```, "JULIA_LOAD_PATH" => join(envs, sep))
+        @test success(cmd)
     finally
         try
             rm(depot_path, force=true, recursive=true)

test/project/Extensions/EnvWithHasExtensions/Manifest.toml

@@ -0,0 +1,29 @@
+# This file is machine-generated - editing it directly is not advised
+
+julia_version = "1.9.0-beta4"
+manifest_format = "2.0"
+project_hash = "caa716752e6dff3d77c3de929ebbb5d2024d04ef"
+
+[[deps.ExtDep]]
+deps = ["SomePackage"]
+path = "../ExtDep.jl"
+uuid = "fa069be4-f60b-4d4c-8b95-f8008775090c"
+version = "0.1.0"
+
+[[deps.HasExtensions]]
+path = "../HasExtensions.jl"
+uuid = "4d3288b3-3afc-4bb6-85f3-489fffe514c8"
+version = "0.1.0"
+
+    [deps.HasExtensions.extensions]
+    Extension = "ExtDep"
+    ExtensionFolder = ["ExtDep", "ExtDep2"]
+
+    [deps.HasExtensions.weakdeps]
+    ExtDep = "fa069be4-f60b-4d4c-8b95-f8008775090c"
+    ExtDep2 = "55982ee5-2ad5-4c40-8cfe-5e9e1b01500d"
+
+[[deps.SomePackage]]
+path = "../SomePackage"
+uuid = "678608ae-7bb3-42c7-98b1-82102067a3d8"
+version = "0.1.0"

test/project/Extensions/EnvWithHasExtensions/Project.toml

@@ -0,0 +1,4 @@
+[deps]
+ExtDep = "fa069be4-f60b-4d4c-8b95-f8008775090c"
+HasExtensions = "4d3288b3-3afc-4bb6-85f3-489fffe514c8"
+SomePackage = "678608ae-7bb3-42c7-98b1-82102067a3d8"

test/project/Extensions/EnvWithHasExtensionsv2/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 = "caa716752e6dff3d77c3de929ebbb5d2024d04ef"
+
+[[deps.ExtDep]]
+deps = ["SomePackage"]
+path = "../ExtDep.jl"
+uuid = "fa069be4-f60b-4d4c-8b95-f8008775090c"
+version = "0.1.0"
+
+[[deps.HasExtensions]]
+path = "../HasExtensions_v2.jl"
+uuid = "4d3288b3-3afc-4bb6-85f3-489fffe514c8"
+version = "0.2.0"
+weakdeps = ["ExtDep"]
+
+    [deps.HasExtensions.extensions]
+    Extension2 = "ExtDep"
+
+[[deps.SomePackage]]
+path = "../SomePackage"
+uuid = "678608ae-7bb3-42c7-98b1-82102067a3d8"
+version = "0.1.0"

test/project/Extensions/EnvWithHasExtensionsv2/Project.toml

@@ -0,0 +1,4 @@
+[deps]
+ExtDep = "fa069be4-f60b-4d4c-8b95-f8008775090c"
+HasExtensions = "4d3288b3-3afc-4bb6-85f3-489fffe514c8"
+SomePackage = "678608ae-7bb3-42c7-98b1-82102067a3d8"

test/project/Extensions/HasExtensions_v2.jl/Project.toml

@@ -0,0 +1,9 @@
+name = "HasExtensions"
+uuid = "4d3288b3-3afc-4bb6-85f3-489fffe514c8"
+version = "0.2.0"
+
+[weakdeps]
+ExtDep = "fa069be4-f60b-4d4c-8b95-f8008775090c"
+
+[extensions]
+Extension2 = "ExtDep"

test/project/Extensions/HasExtensions_v2.jl/ext/Extension2.jl

@@ -0,0 +1,3 @@
+module Extension2
+
+end

test/project/Extensions/HasExtensions_v2.jl/src/HasExtensions.jl

@@ -0,0 +1,10 @@
+module HasExtensions
+
+struct HasExtensionsStruct end
+
+foo(::HasExtensionsStruct) = 1
+
+ext_loaded = false
+ext_folder_loaded = false
+
+end # module