Add WT_PROFILE_ID to the environment of the spawned process (#4852)

This commit adds a `WT_PROFILE_ID` environment variable, which contains
the guid of the active profile.

It also teaches ConptyConnection to take an environment map on creation.

We had to do a little manual jiggery with the WSLENV environment
variable as passed by the creator.

* [x] CLA signed
* [ ] Tests added/passed
* [ ] Requires documentation to be updated
* [x] I've discussed this with core contributors already.

Ran terminal, validated vars and translated paths under windows and WSL. 

References #4566 (this PR originally introduced WT_SETTINGS/DEFAULTS)
Closes #3589

.github/actions/spell-check/dictionary/apis.txt

@@ -1,3 +1,4 @@
+IMap
 ICustom
 IObject
 LCID

src/cascadia/TerminalApp/TerminalPage.cpp

@@ -19,6 +19,7 @@
 #include "DebugTapConnection.h"
 
 using namespace winrt;
+using namespace winrt::Windows::Foundation::Collections;
 using namespace winrt::Windows::UI::Xaml;
 using namespace winrt::Windows::UI::Core;
 using namespace winrt::Windows::System;
@@ -572,7 +573,13 @@ namespace winrt::TerminalApp::implementation
             // TODO GH#4661: Replace this with directly using the AzCon when our VT is better
             std::filesystem::path azBridgePath{ wil::GetModuleFileNameW<std::wstring>(nullptr) };
             azBridgePath.replace_filename(L"TerminalAzBridge.exe");
-            connection = TerminalConnection::ConptyConnection(azBridgePath.wstring(), L".", L"Azure", settings.InitialRows(), settings.InitialCols(), winrt::guid());
+            connection = TerminalConnection::ConptyConnection(azBridgePath.wstring(),
+                                                              L".",
+                                                              L"Azure",
+                                                              nullptr,
+                                                              settings.InitialRows(),
+                                                              settings.InitialCols(),
+                                                              winrt::guid());
         }
 
         else if (profile->HasConnectionType() &&
@@ -583,12 +590,21 @@ namespace winrt::TerminalApp::implementation
 
         else
         {
-            auto conhostConn = TerminalConnection::ConptyConnection(settings.Commandline(),
-                                                                    settings.StartingDirectory(),
-                                                                    settings.StartingTitle(),
-                                                                    settings.InitialRows(),
-                                                                    settings.InitialCols(),
-                                                                    winrt::guid());
+            std::wstring guidWString = Utils::GuidToString(profileGuid);
+
+            StringMap envMap{};
+            envMap.Insert(L"WT_PROFILE_ID", guidWString);
+            envMap.Insert(L"WSLENV", L"WT_PROFILE_ID");
+
+            auto conhostConn = TerminalConnection::ConptyConnection(
+                settings.Commandline(),
+                settings.StartingDirectory(),
+                settings.StartingTitle(),
+                envMap.GetView(),
+                settings.InitialRows(),
+                settings.InitialCols(),
+                winrt::guid());
+
             sessionGuid = conhostConn.Guid();
             connection = conhostConn;
         }

src/cascadia/TerminalConnection/ConptyConnection.cpp

@@ -13,7 +13,7 @@
 
 #include "ConptyConnection.g.cpp"
 
-#include "../../types/inc/Utils.hpp"
+#include "../../types/inc/utils.hpp"
 #include "../../types/inc/Environment.hpp"
 #include "LibraryResources.h"
 
@@ -110,9 +110,29 @@ namespace winrt::Microsoft::Terminal::TerminalConnection::implementation
             // Ensure every connection has the unique identifier in the environment.
             environment.insert_or_assign(L"WT_SESSION", guidSubStr.data());
 
-            auto wslEnv = environment[L"WSLENV"]; // We always want to load something, even if it's blank.
+            if (_environment)
+            {
+                // add additional WT env vars like WT_SETTINGS, WT_DEFAULTS and WT_PROFILE_ID
+                for (auto item : _environment)
+                {
+                    auto key = item.Key();
+                    auto value = item.Value();
+
+                    // avoid clobbering WSLENV
+                    if (std::wstring_view{ key } == L"WSLENV")
+                    {
+                        auto current = environment[L"WSLENV"];
+                        value = current + L":" + value;
+                    }
+
+                    environment.insert_or_assign(key.c_str(), value.c_str());
+                }
+            }
+
             // WSLENV is a colon-delimited list of environment variables (+flags) that should appear inside WSL
             // https://devblogs.microsoft.com/commandline/share-environment-vars-between-wsl-and-windows/
+
+            auto wslEnv = environment[L"WSLENV"];
             wslEnv = L"WT_SESSION:" + wslEnv; // prepend WT_SESSION to make sure it's visible inside WSL.
             environment.insert_or_assign(L"WSLENV", wslEnv);
         }
@@ -173,6 +193,7 @@ namespace winrt::Microsoft::Terminal::TerminalConnection::implementation
     ConptyConnection::ConptyConnection(const hstring& commandline,
                                        const hstring& startingDirectory,
                                        const hstring& startingTitle,
+                                       const Windows::Foundation::Collections::IMapView<hstring, hstring>& environment,
                                        const uint32_t initialRows,
                                        const uint32_t initialCols,
                                        const guid& initialGuid) :
@@ -181,6 +202,7 @@ namespace winrt::Microsoft::Terminal::TerminalConnection::implementation
         _commandline{ commandline },
         _startingDirectory{ startingDirectory },
         _startingTitle{ startingTitle },
+        _environment{ environment },
         _guid{ initialGuid },
         _u8State{},
         _u16Str{},

src/cascadia/TerminalConnection/ConptyConnection.h

@@ -19,7 +19,14 @@ namespace winrt::Microsoft::Terminal::TerminalConnection::implementation
 {
     struct ConptyConnection : ConptyConnectionT<ConptyConnection>, ConnectionStateHolder<ConptyConnection>
     {
-        ConptyConnection(const hstring& cmdline, const hstring& startingDirectory, const hstring& startingTitle, const uint32_t rows, const uint32_t cols, const guid& guid);
+        ConptyConnection(
+            const hstring& cmdline,
+            const hstring& startingDirectory,
+            const hstring& startingTitle,
+            const Windows::Foundation::Collections::IMapView<hstring, hstring>& environment,
+            const uint32_t rows,
+            const uint32_t cols,
+            const guid& guid);
 
         void Start();
         void WriteInput(hstring const& data);
@@ -40,6 +47,7 @@ namespace winrt::Microsoft::Terminal::TerminalConnection::implementation
         hstring _commandline;
         hstring _startingDirectory;
         hstring _startingTitle;
+        Windows::Foundation::Collections::IMapView<hstring, hstring> _environment;
         guid _guid{}; // A unique session identifier for connected client
         hstring _clientName{}; // The name of the process hosted by this ConPTY connection (as of launch).
 

src/cascadia/TerminalConnection/ConptyConnection.idl

@@ -8,7 +8,7 @@ namespace Microsoft.Terminal.TerminalConnection
     [default_interface]
     runtimeclass ConptyConnection : ITerminalConnection
     {
-        ConptyConnection(String cmdline, String startingDirectory, String startingTitle, UInt32 rows, UInt32 columns, Guid guid);
+        ConptyConnection(String cmdline, String startingDirectory, String startingTitle, IMapView<String,String> environment, UInt32 rows, UInt32 columns, Guid guid);
         Guid Guid { get; };
     };