Codesign macOS libraries after modifying them

Author: staticfloat

stdlib/Libdl/test/runtests.jl

@@ -267,6 +267,12 @@ end
 
 ## Tests for LazyLibrary
 @testset "LazyLibrary" begin; mktempdir() do dir
+    # We require `codesign` to run these tests
+    if Sys.isapple() && Sys.which("codesign") === nothing
+        @warn("Unable to run `LazyLibrary` tests on macOS without `codesign` tool!")
+        return
+    end
+
     # Create custom-named libccalltest libraries, to avoid failing these tests
     # because some other test has already loaded `libccalltest` via `ccall()` or somesuch
     lct_name  = "libcc4llt3st"
@@ -283,6 +289,19 @@ end
     str_replace(lct_path, "libccalltest" => lct_name)
     str_replace(lctd_path, "libccalltest" => lct_name)
 
+    # If we're on macOS, we need to codesign after modifying these libraries.
+    if Sys.isapple()
+        function read_stderr(cmd)
+            io = IOBuffer()
+            run(pipeline(cmd; stderr=io))
+            return String(take!(io))
+        end
+        out = read_stderr(`codesign --sign - --option=runtime --timestamp --force $(lct_path)`)
+        @test endswith(out, "replacing existing signature\n")
+        out = read_stderr(`codesign --sign - --option=runtime --timestamp --force $(lctd_path)`)
+        @test endswith(out, "replacing existing signature\n")
+    end
+
     default_rtld_flags = Base.Libc.Libdl.default_rtld_flags
     # Ensure that our modified copy of `libccalltest` is not currently loaded
     @test !any(contains.(dllist(), lct_path))