fix project hash handling

src/Operations.jl

@@ -1421,12 +1421,17 @@ function add(ctx::Context, pkgs::Vector{PackageSpec}, new_git=Set{UUID}();
             end
             printpkgstyle(ctx.io, :Compat, """entries added for $(join(compat_names, ", "))""")
         end
-        record_project_hash(ctx.env) # compat entries changed the hash after it was last recorded in update_manifest!
+        Types.write_project(ctx.env)
+
+        # if the project has a pkg in deps and weakdeps write_project changes the project entries
+        # so we have to re-read to make sure we can hash the project properly
+        ctx2 = Types.Context()
+        record_project_hash(ctx2.env)
+        Types.write_manifest(ctx2.env)
 
-        write_env(ctx.env) # write env before building
         show_update(ctx.env, ctx.registries; io=ctx.io)
         build_versions(ctx, union(new_apply, new_git))
-        Pkg._auto_precompile(ctx)
+        Pkg._auto_precompile(ctx2) # use ctx2 otherwise weakdeps that are in deps will be attempted and fail
     else
         record_project_hash(ctx.env)
         write_env(ctx.env)