[vcpkg] Apply fixes needed to extract vcpkg-tool (#16012)

utilities.cmake: Disable warnings that are firing on Azure Pipelines CI machines due to different Clang version.

expected.h: Fix a bug I introduced in https://github.com/microsoft/vcpkg/pull/15638/ because I was under the impression expected worked like optional (in that value_or_exit for it should be treated as a program bug)

build.cpp: Add (void)s to silence warnings.

binarycaching.cpp: Repair assumption that the current directory is C: which isn't true on the Hosted Azure Pipelines agents.

others: Make unit tests respect %VCPKG_ROOT%, as necessary in the vcpkg_tool repo. Note that this required splitting vcpkgcmdarguments::ImbueFromEnvironment into the once-only process modifying part and the just imbue from environment part.

1 files changed, 1 insertions, 0 deletions

diff --git a/toolsrc/src/vcpkg-test/manifests.cpp b/toolsrc/src/vcpkg-test/manifests.cpp
index 7cf92818e..bbbe0c96c 100644
--- a/toolsrc/src/vcpkg-test/manifests.cpp
+++ b/toolsrc/src/vcpkg-test/manifests.cpp
@@ -681,6 +681,7 @@ TEST_CASE ("Serialize all the ports", "[manifests]")
     std::vector<std::string> args_list = {"format-manifest"};
     auto& fs = Files::get_real_filesystem();
     auto args = VcpkgCmdArguments::create_from_arg_sequence(args_list.data(), args_list.data() + args_list.size());
+    args.imbue_from_environment();
     VcpkgPaths paths{fs, args};
 
     std::vector<SourceControlFile> scfs;