From f4ddfd02a56d54838140dc269b09af5a34d25077 Mon Sep 17 00:00:00 2001
From: Ilona Tomkowicz <32700855+ilonatommy@users.noreply.github.com>
Date: Tue, 17 Jun 2025 14:55:07 +0000
Subject: [PATCH 1/4] Windows, fix: `export' is not recognized as an internal
 or external command.

---
 eng/testing/xunit/xunit.console.targets | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/eng/testing/xunit/xunit.console.targets b/eng/testing/xunit/xunit.console.targets
index b682117b75a9ec..89567bb43fef81 100644
--- a/eng/testing/xunit/xunit.console.targets
+++ b/eng/testing/xunit/xunit.console.targets
@@ -13,8 +13,8 @@
 
   <ItemGroup>
     <!-- Configures xunit to not print out passing tests with output when diagnostic messages are enabled. -->
-    <SetScriptCommands Condition="'$(TargetOS)' == 'windows'" Include="set XUNIT_HIDE_PASSING_OUTPUT_DIAGNOSTICS=1" />
-    <SetScriptCommands Condition="'$(TargetOS)' != 'windows'" Include="export XUNIT_HIDE_PASSING_OUTPUT_DIAGNOSTICS=1" />
+    <SetScriptCommands Condition="'$(OS)' == 'Windows_NT'" Include="set XUNIT_HIDE_PASSING_OUTPUT_DIAGNOSTICS=1" />
+    <SetScriptCommands Condition="'$(OS)' != 'Windows_NT'" Include="export XUNIT_HIDE_PASSING_OUTPUT_DIAGNOSTICS=1" />
   </ItemGroup>
 
   <PropertyGroup Condition="'$(BundleXunitRunner)' == 'true'">

From 7273e9f2fb9f6c559a839e4cbcd941c85a075433 Mon Sep 17 00:00:00 2001
From: Ilona Tomkowicz <itomkowicz@microsoft.com>
Date: Wed, 18 Jun 2025 13:46:33 +0200
Subject: [PATCH 2/4] Unify setting env var in lib tests.

---
 eng/testing/tests.browser.targets       | 35 +++++++++----------------
 eng/testing/tests.props                 |  7 +++--
 eng/testing/tests.targets               |  3 +--
 eng/testing/tests.wasi.targets          | 10 +++----
 eng/testing/xunit/xunit.console.targets |  3 +--
 5 files changed, 22 insertions(+), 36 deletions(-)

diff --git a/eng/testing/tests.browser.targets b/eng/testing/tests.browser.targets
index 4264bde6d01999..911719ab33faa6 100644
--- a/eng/testing/tests.browser.targets
+++ b/eng/testing/tests.browser.targets
@@ -71,22 +71,16 @@
     Any settings in the project file could be replaced on Helix.
     See also eng\testing\WasmRunnerTemplate.sh
     -->
-  <ItemGroup Condition="'$(OS)' != 'Windows_NT'">
-    <SetScriptCommands Condition="'$(Scenario)' != '' and '$(ContinuousIntegrationBuild)' != 'true'" Include="export SCENARIO=$(Scenario)" />
-    <SetScriptCommands Condition="'$(JSEngine)' != ''" Include="export JS_ENGINE=--engine=$(JSEngine)" />
-    <SetScriptCommands Condition="'$(JSEngineArgs)' != ''" Include="export JS_ENGINE_ARGS=$(JSEngineArgs)" />
-    <SetScriptCommands Condition="'$(_WasmJSEnginePathForTests)' != ''" Include="export V8_PATH_FOR_TESTS=${V8_PATH_FOR_TESTS:=$(_WasmJSEnginePathForTests)}" />
-    <SetScriptCommands Condition="'$(_WasmMainJSFileName)' != ''" Include="export MAIN_JS=--js-file=$(_WasmMainJSFileName)" />
+  <ItemGroup>
+    <SetScriptCommands Condition="'$(Scenario)' != '' and '$(ContinuousIntegrationBuild)' != 'true'" Include="$(EnvVarCommand) &quot;SCENARIO=$(Scenario)&quot;" />
+    <SetScriptCommands Condition="'$(JSEngine)' != ''" Include="$(EnvVarCommand) &quot;JS_ENGINE=--engine^=$(JSEngine)&quot;" />
+    <SetScriptCommands Condition="'$(JSEngineArgs)' != ''" Include="$(EnvVarCommand) &quot;JS_ENGINE_ARGS=$(JSEngineArgs)&quot;" />
+    <SetScriptCommands Condition="'$(_WasmMainJSFileName)' != ''" Include="$(EnvVarCommand) &quot;MAIN_JS=--js-file^=$(_WasmMainJSFileName)&quot;" />
     <!-- Workaround for https://github.com/dotnet/runtime/issues/74328 -->
-    <SetScriptCommands Condition="'$(BuildAOTTestsOnHelix)' == 'true'" Include="export DOTNET_CLI_DO_NOT_USE_MSBUILD_SERVER=1" />
+    <SetScriptCommands Condition="'$(BuildAOTTestsOnHelix)' == 'true'" Include="$(EnvVarCommand) DOTNET_CLI_DO_NOT_USE_MSBUILD_SERVER=1" />
   </ItemGroup>
-  <ItemGroup Condition="'$(OS)' == 'Windows_NT'">
-    <SetScriptCommands Condition="'$(Scenario)' != '' and '$(ContinuousIntegrationBuild)' != 'true'" Include="set &quot;SCENARIO=$(Scenario)&quot;" />
-    <SetScriptCommands Condition="'$(JSEngine)' != ''" Include="set &quot;JS_ENGINE=--engine^=$(JSEngine)&quot;" />
-    <SetScriptCommands Condition="'$(JSEngineArgs)' != ''" Include="set &quot;JS_ENGINE_ARGS=$(JSEngineArgs)&quot;" />
-    <SetScriptCommands Condition="'$(_WasmMainJSFileName)' != ''" Include="set &quot;MAIN_JS=--js-file^=$(_WasmMainJSFileName)&quot;" />
-    <!-- Workaround for https://github.com/dotnet/runtime/issues/74328 -->
-    <SetScriptCommands Condition="'$(BuildAOTTestsOnHelix)' == 'true'" Include="set DOTNET_CLI_DO_NOT_USE_MSBUILD_SERVER=1" />
+  <ItemGroup Condition="'$(OS)' != 'Windows_NT'">
+    <SetScriptCommands Condition="'$(_WasmJSEnginePathForTests)' != ''" Include="$(EnvVarCommand) V8_PATH_FOR_TESTS=${V8_PATH_FOR_TESTS:=$(_WasmJSEnginePathForTests)}" />
   </ItemGroup>
 
   <PropertyGroup>
@@ -251,15 +245,10 @@
                       Text="Only supported scenarios are WasmTestOnV8, WasmTestOnChrome, WasmTestOnFirefox and BuildWasmApps at the moment. It was $(Scenario)." />
 
     <!-- Restore NPM packages -->
-    <ItemGroup Condition="'$(OS)' != 'Windows_NT'">
-      <SetScriptCommands Condition="'$(InstallChromeForTests)' == 'true' and '$(ChromeDriverBinaryPath)' != ''" Include="export PREPEND_PATH=$([System.IO.Path]::GetDirectoryName($(ChromeDriverBinaryPath)))" />
-      <SetScriptCommands Condition="'$(InstallFirefoxForTests)' == 'true' and '$(GeckoDriverBinaryPath)' != ''" Include="export PREPEND_PATH=$([System.IO.Path]::GetDirectoryName($(GeckoDriverBinaryPath)))" />
-      <SetScriptCommands Condition="'$(IsBrowserWasmProject)' == 'true'" Include="export RuntimeIdentifier=browser-wasm" />
-    </ItemGroup>
-    <ItemGroup Condition="'$(OS)' == 'Windows_NT'">
-      <SetScriptCommands Condition="'$(InstallChromeForTests)' == 'true' and '$(ChromeDriverBinaryPath)' != ''" Include="set PREPEND_PATH=$([System.IO.Path]::GetDirectoryName($(ChromeDriverBinaryPath)))" />
-      <SetScriptCommands Condition="'$(InstallFirefoxForTests)' == 'true' and '$(GeckoDriverBinaryPath)' != ''" Include="set PREPEND_PATH=$([System.IO.Path]::GetDirectoryName($(GeckoDriverBinaryPath)))" />
-      <SetScriptCommands Condition="'$(IsBrowserWasmProject)' == 'true'" Include="set RuntimeIdentifier=browser-wasm" />
+    <ItemGroup>
+      <SetScriptCommands Condition="'$(InstallChromeForTests)' == 'true' and '$(ChromeDriverBinaryPath)' != ''" Include="$(EnvVarCommand) PREPEND_PATH=$([System.IO.Path]::GetDirectoryName($(ChromeDriverBinaryPath)))" />
+      <SetScriptCommands Condition="'$(InstallFirefoxForTests)' == 'true' and '$(GeckoDriverBinaryPath)' != ''" Include="$(EnvVarCommand) PREPEND_PATH=$([System.IO.Path]::GetDirectoryName($(GeckoDriverBinaryPath)))" />
+      <SetScriptCommands Condition="'$(IsBrowserWasmProject)' == 'true'" Include="$(EnvVarCommand) RuntimeIdentifier=browser-wasm" />
     </ItemGroup>
   </Target>
 </Project>
diff --git a/eng/testing/tests.props b/eng/testing/tests.props
index ad0f25da5fa054..5ff71ec66cc51f 100644
--- a/eng/testing/tests.props
+++ b/eng/testing/tests.props
@@ -9,6 +9,10 @@
     <ILLinkDescriptorsPath>$(MSBuildThisFileDirectory)ILLinkDescriptors\</ILLinkDescriptorsPath>
     <TestSingleFile Condition="'$(TestNativeAot)' == 'true'">true</TestSingleFile>
     <TestSingleFile Condition="'$(TestReadyToRun)' == 'true'">true</TestSingleFile>
+    <EnvVarCommand Condition="'$(OS)' == 'Windows_NT' or '$(TargetsWindows)' == 'true' or '$(TargetPlatformIdentifier)' == 'windows'">set</EnvVarCommand>
+    <EnvVarCommand Condition="'$(OS)' != 'Windows_NT' and '$(TargetsWindows)' != 'true' and '$(TargetPlatformIdentifier)' != 'windows'">export</EnvVarCommand>
+    <DirSeparator Condition="'$(OS)' == 'Windows_NT'">\\</DirSeparator>
+    <DirSeparator Condition="'$(OS)' != 'Windows_NT'">/</DirSeparator>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(TargetsMobile)' == 'true'">
@@ -27,8 +31,7 @@
 
   <!-- Provide runtime options to Mono (interpreter, aot, debugging, etc) -->
   <ItemGroup Condition="'$(MonoEnvOptions)' != '' and '$(TargetsMobile)' != 'true'">
-    <RunScriptCommands Condition="'$(TargetsWindows)' == 'true' or '$(TargetPlatformIdentifier)' == 'windows'" Include="set MONO_ENV_OPTIONS='$(MonoEnvOptions)'" />
-    <RunScriptCommands Condition="'$(TargetsWindows)' != 'true' and '$(TargetPlatformIdentifier)' != 'windows'" Include="export MONO_ENV_OPTIONS='$(MonoEnvOptions)'" />
+    <RunScriptCommands Include="$(EnvVarCommand) MONO_ENV_OPTIONS='$(MonoEnvOptions)'" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(TestRunRequiresLiveRefPack)' == 'true'">
diff --git a/eng/testing/tests.targets b/eng/testing/tests.targets
index f05b4aa2a67c7b..f7fb50dced1c5f 100644
--- a/eng/testing/tests.targets
+++ b/eng/testing/tests.targets
@@ -71,8 +71,7 @@
   <ItemGroup Condition="'$(IsXUnitLogCheckerSupported)' == 'true' and
                         '$(TargetFrameworkIdentifier)' == '.NETCoreApp' and
                          $([MSBuild]::VersionGreaterThanOrEquals($(TargetFrameworkVersion), '$(NETCoreAppCurrentVersion)'))">
-    <SetScriptCommands Condition="'$(TargetOS)' == 'windows'" Include="set __IsXUnitLogCheckerSupported=1" />
-    <SetScriptCommands Condition="'$(TargetOS)' != 'windows'" Include="export __IsXUnitLogCheckerSupported=1" />
+    <SetScriptCommands Include="$(EnvVarCommand) __IsXUnitLogCheckerSupported=1" />
   </ItemGroup>
 
   <!-- Archive test binaries. -->
diff --git a/eng/testing/tests.wasi.targets b/eng/testing/tests.wasi.targets
index 066c4391ad4503..52f72440d76d72 100644
--- a/eng/testing/tests.wasi.targets
+++ b/eng/testing/tests.wasi.targets
@@ -151,13 +151,9 @@
                       '$(Scenario)' != 'BuildWasmApps'"
                       Text="Only supported scenarios are WasmTestOnWasmtime and BuildWasmApps at the moment. It was $(Scenario)." />
 
-    <ItemGroup Condition="'$(OS)' != 'Windows_NT'">
-      <SetScriptCommands Condition="'$(InstallWasmtimeForTests)' == 'true' and Exists($(WasmtimeDir))" Include="export PREPEND_PATH=$(WasmtimeDir)" />
-      <SetScriptCommands Condition="'$(IsWasiProject)' == 'true'" Include="export RuntimeIdentifier=wasi-wasm" />
-    </ItemGroup>
-    <ItemGroup Condition="'$(OS)' == 'Windows_NT'">
-      <SetScriptCommands Condition="'$(InstallWasmtimeForTests)' == 'true' and Exists($(WasmtimeDir))" Include="set PREPEND_PATH=$(WasmtimeDir)" />
-      <SetScriptCommands Condition="'$(IsWasiProject)' == 'true'" Include="set RuntimeIdentifier=wasi-wasm" />
+    <ItemGroup >
+      <SetScriptCommands Condition="'$(InstallWasmtimeForTests)' == 'true' and Exists($(WasmtimeDir))" Include="$(EnvVarCommand) PREPEND_PATH=$(WasmtimeDir)" />
+      <SetScriptCommands Condition="'$(IsWasiProject)' == 'true'" Include="$(EnvVarCommand) RuntimeIdentifier=wasi-wasm" />
     </ItemGroup>
   </Target>
 </Project>
diff --git a/eng/testing/xunit/xunit.console.targets b/eng/testing/xunit/xunit.console.targets
index 89567bb43fef81..cb79571f2f1d5c 100644
--- a/eng/testing/xunit/xunit.console.targets
+++ b/eng/testing/xunit/xunit.console.targets
@@ -13,8 +13,7 @@
 
   <ItemGroup>
     <!-- Configures xunit to not print out passing tests with output when diagnostic messages are enabled. -->
-    <SetScriptCommands Condition="'$(OS)' == 'Windows_NT'" Include="set XUNIT_HIDE_PASSING_OUTPUT_DIAGNOSTICS=1" />
-    <SetScriptCommands Condition="'$(OS)' != 'Windows_NT'" Include="export XUNIT_HIDE_PASSING_OUTPUT_DIAGNOSTICS=1" />
+    <SetScriptCommands Include="$(EnvVarCommand) XUNIT_HIDE_PASSING_OUTPUT_DIAGNOSTICS=1" />
   </ItemGroup>
 
   <PropertyGroup Condition="'$(BundleXunitRunner)' == 'true'">

From 0d38e7ed2d9a7f3b335bcb3b76fd9cd78b8b4297 Mon Sep 17 00:00:00 2001
From: Ilona Tomkowicz <itomkowicz@microsoft.com>
Date: Mon, 24 Nov 2025 11:46:48 +0100
Subject: [PATCH 3/4] Remaining optimization.

---
 src/libraries/sendtohelix-browser.targets | 40 ++++++++++-------------
 src/libraries/sendtohelix-wasi.targets    | 23 +++++++------
 src/libraries/sendtohelix-wasm.targets    | 25 ++++++--------
 3 files changed, 39 insertions(+), 49 deletions(-)

diff --git a/src/libraries/sendtohelix-browser.targets b/src/libraries/sendtohelix-browser.targets
index eba7ec0e95f2c7..d3a92fbac1e7bf 100644
--- a/src/libraries/sendtohelix-browser.targets
+++ b/src/libraries/sendtohelix-browser.targets
@@ -91,30 +91,26 @@
     />
   </ItemGroup>
 
-  <ItemGroup Condition="'$(WindowsShell)' != 'true'">
-    <HelixPreCommand Condition="'$(Scenario)' != ''" Include="export SCENARIO=$(Scenario)" />
-
-    <HelixPreCommand Include="export XHARNESS_DISABLE_COLORED_OUTPUT=true" />
-    <HelixPreCommand Include="export XHARNESS_LOG_WITH_TIMESTAMPS=true" />
+  <ItemGroup>
+    <HelixPreCommand Condition="'$(Scenario)' != ''" Include="$(EnvVarCommand) SCENARIO=$(Scenario)" />
+    <HelixPreCommand Include="$(EnvVarCommand) XHARNESS_DISABLE_COLORED_OUTPUT=true" />
+    <HelixPreCommand Include="$(EnvVarCommand) XHARNESS_LOG_WITH_TIMESTAMPS=true" />
+  </ItemGroup>
 
-    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="export PATH=$HELIX_CORRELATION_PAYLOAD/$(ChromeDriverDirName):$PATH" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="export PATH=$HELIX_CORRELATION_PAYLOAD/$(ChromeDirName):$PATH" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="export PATH=$HELIX_CORRELATION_PAYLOAD/$(GeckoDriverDirName):$PATH" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="export PATH=$HELIX_CORRELATION_PAYLOAD/$(FirefoxDirName):$PATH" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnV8)' == 'true'" Include="export V8_PATH_FOR_TESTS=$HELIX_CORRELATION_PAYLOAD/$(V8DirName)/$(V8BinaryName)" />
+  <ItemGroup Condition="'$(WindowsShell)' != 'true'">
+    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="(EnvVarCommand) PATH=$HELIX_CORRELATION_PAYLOAD/$(ChromeDriverDirName):$PATH" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="(EnvVarCommand) PATH=$HELIX_CORRELATION_PAYLOAD/$(ChromeDirName):$PATH" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="(EnvVarCommand) PATH=$HELIX_CORRELATION_PAYLOAD/$(GeckoDriverDirName):$PATH" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="(EnvVarCommand) PATH=$HELIX_CORRELATION_PAYLOAD/$(FirefoxDirName):$PATH" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnV8)' == 'true'" Include="(EnvVarCommand) V8_PATH_FOR_TESTS=$HELIX_CORRELATION_PAYLOAD/$(V8DirName)/$(V8BinaryName)" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(WindowsShell)' == 'true'">
-    <HelixPreCommand Condition="'$(Scenario)' != ''" Include="set SCENARIO=$(Scenario)" />
-
-    <HelixPreCommand Include="set XHARNESS_DISABLE_COLORED_OUTPUT=true" />
-    <HelixPreCommand Include="set XHARNESS_LOG_WITH_TIMESTAMPS=true" />
-
-    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="set PATH=%HELIX_CORRELATION_PAYLOAD%\$(ChromeDriverDirName)%3B%PATH%" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="set PATH=%HELIX_CORRELATION_PAYLOAD%\$(ChromeDirName)%3B%PATH%" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="set PATH=%HELIX_CORRELATION_PAYLOAD%\$(GeckoDriverDirName)%3B%PATH%" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="set PATH=%HELIX_CORRELATION_PAYLOAD%\$(FirefoxDirName)%3B%PATH%" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnV8)' == 'true'" Include="set V8_PATH_FOR_TESTS=%HELIX_CORRELATION_PAYLOAD%\$(V8DirName)\$(V8BinaryName)" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\$(ChromeDriverDirName)%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\$(ChromeDirName)%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\$(GeckoDriverDirName)%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\$(FirefoxDirName)%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnV8)' == 'true'" Include="(EnvVarCommand) V8_PATH_FOR_TESTS=%HELIX_CORRELATION_PAYLOAD%\$(V8DirName)\$(V8BinaryName)" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(NeedsEMSDKNode)' == 'true' and '$(WindowsShell)' != 'true'">
@@ -129,8 +125,8 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(NeedsEMSDKNode)' == 'true' and '$(WindowsShell)' == 'true'">
-    <HelixPreCommand Include="for /f %%i in ('dir $(_HelixLocalNodePath) /b') do set _HELIX_NODEJS_VERSION=%%i" />
-    <HelixPreCommand Include="set PATH=$(_HelixLocalNodePath)/%_HELIX_NODEJS_VERSION%/bin%3B%PATH%" />
+    <HelixPreCommand Include="for /f %%i in ('dir $(_HelixLocalNodePath) /b') do (EnvVarCommand) _HELIX_NODEJS_VERSION=%%i" />
+    <HelixPreCommand Include="(EnvVarCommand) PATH=$(_HelixLocalNodePath)/%_HELIX_NODEJS_VERSION%/bin%3B%PATH%" />
   </ItemGroup>
 
   <PropertyGroup Condition="'$(Scenario)' == 'BuildWasmApps'">
diff --git a/src/libraries/sendtohelix-wasi.targets b/src/libraries/sendtohelix-wasi.targets
index ccb4e68c2db60c..a4aefcfdeab107 100644
--- a/src/libraries/sendtohelix-wasi.targets
+++ b/src/libraries/sendtohelix-wasi.targets
@@ -61,22 +61,21 @@
     <SdkForWorkloadTestingDirName Condition="'$(NeedsWorkload)' == 'true' and '$(TestUsingWorkloads)' != 'true'">dotnet-none</SdkForWorkloadTestingDirName>
   </PropertyGroup>
 
+  <ItemGroup>
+    <HelixPreCommand Condition="'$(Scenario)' != ''" Include="$(EnvVarCommand) SCENARIO=$(Scenario)" />
+    <HelixPreCommand Include="$(EnvVarCommand) XHARNESS_DISABLE_COLORED_OUTPUT=true" />
+    <HelixPreCommand Include="$(EnvVarCommand) XHARNESS_LOG_WITH_TIMESTAMPS=true" />
+    <HelixPreCommand Include="$(EnvVarCommand) WASMTIME_BACKTRACE_DETAILS=1" />
+  </ItemGroup>
+
   <ItemGroup Condition="'$(WindowsShell)' != 'true'">
-    <HelixPreCommand Condition="'$(Scenario)' != ''" Include="export SCENARIO=$(Scenario)" />
-    <HelixPreCommand Include="export XHARNESS_DISABLE_COLORED_OUTPUT=true" />
-    <HelixPreCommand Include="export XHARNESS_LOG_WITH_TIMESTAMPS=true" />
-    <HelixPreCommand Include="export WASMTIME_BACKTRACE_DETAILS=1" />
     <HelixPreCommand Condition="'$(NeedsWasmtime)' == 'true'" Include="export PATH=$HELIX_CORRELATION_PAYLOAD/wasmtime:$PATH" />
     <HelixPreCommand Condition="'$(NeedsWasiSdk)' == 'true'" Include="export PATH=$HELIX_CORRELATION_PAYLOAD/build/wasi-sdk/bin:$PATH" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(WindowsShell)' == 'true'">
-    <HelixPreCommand Condition="'$(Scenario)' != ''" Include="set SCENARIO=$(Scenario)" />
-    <HelixPreCommand Include="set XHARNESS_DISABLE_COLORED_OUTPUT=true" />
-    <HelixPreCommand Include="set XHARNESS_LOG_WITH_TIMESTAMPS=true" />
-    <HelixPreCommand Include="set WASMTIME_BACKTRACE_DETAILS=1" />
-    <HelixPreCommand Condition="'$(NeedsWasmtime)' == 'true'" Include="set PATH=%HELIX_CORRELATION_PAYLOAD%\wasmtime%3B%PATH%" />
-    <HelixPreCommand Condition="'$(NeedsWasiSdk)' == 'true'" Include="set PATH=%HELIX_CORRELATION_PAYLOAD%\build\wasi-sdk\bin%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsWasmtime)' == 'true'" Include="(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\wasmtime%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsWasiSdk)' == 'true'" Include="(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\build\wasi-sdk\bin%3B%PATH%" />
   </ItemGroup>
 
   <PropertyGroup Condition="'$(Scenario)' == 'BuildWasmApps'">
@@ -86,8 +85,8 @@
   </PropertyGroup>
 
   <ItemGroup Condition="'$(Scenario)' == 'BuildWasmApps'">
-    <HelixPreCommand Condition="'$(WindowsShell)' == 'true'" Include="set &quot;WASI_SDK_PATH=%HELIX_CORRELATION_PAYLOAD%\build\wasi-sdk&quot;" />
-    <HelixPreCommand Condition="'$(WindowsShell)' != 'true'" Include="export &quot;WASI_SDK_PATH=$HELIX_CORRELATION_PAYLOAD/build/wasi-sdk&quot;" />
+    <HelixPreCommand Condition="'$(WindowsShell)' == 'true'" Include="$(EnvVarCommand) &quot;WASI_SDK_PATH=%HELIX_CORRELATION_PAYLOAD%\build\wasi-sdk&quot;" />
+    <HelixPreCommand Condition="'$(WindowsShell)' != 'true'" Include="$(EnvVarCommand) &quot;WASI_SDK_PATH=$HELIX_CORRELATION_PAYLOAD/build/wasi-sdk&quot;" />
   </ItemGroup>
 
   <PropertyGroup Condition="'$(NeedsWasiSdk)' == 'true'">
diff --git a/src/libraries/sendtohelix-wasm.targets b/src/libraries/sendtohelix-wasm.targets
index 3a8b618f54f3d9..9ad6d03cc16adf 100644
--- a/src/libraries/sendtohelix-wasm.targets
+++ b/src/libraries/sendtohelix-wasm.targets
@@ -7,6 +7,9 @@
 
     <BrowserBuildTargetsDir>$([MSBuild]::NormalizeDirectory($(BrowserProjectRoot), 'build'))</BrowserBuildTargetsDir>
     <WasmBuildTargetsDir>$([MSBuild]::NormalizeDirectory($(WasmProjectRoot), 'build'))</WasmBuildTargetsDir>
+
+    <EnvVarCommand Condition="'$(WindowsShell)' == 'true'">set</EnvVarCommand>
+    <EnvVarCommand Condition="'$(WindowsShell)' != 'true'">export</EnvVarCommand>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Scenario)' == 'BuildWasmApps'">
@@ -20,20 +23,13 @@
   </PropertyGroup>
 
   <ItemGroup Condition="'$(Scenario)' == 'BuildWasmApps'">
-    <HelixPreCommand Condition="'$(WindowsShell)' == 'true'" Include="set &quot;XUnitTraitArg=$(_XUnitTraitArg)&quot;" />
-    <HelixPreCommand Condition="'$(WindowsShell)' != 'true'" Include="export &quot;XUnitTraitArg=$(_XUnitTraitArg)&quot;" />
-
-    <HelixPreCommand Condition="'$(WindowsShell)' == 'true'" Include="set &quot;BUILT_NUGETS_PATH=%HELIX_CORRELATION_PAYLOAD%/built-nugets&quot;" />
-    <HelixPreCommand Condition="'$(WindowsShell)' != 'true'" Include="export &quot;BUILT_NUGETS_PATH=$HELIX_CORRELATION_PAYLOAD/built-nugets&quot;" />
-
-    <HelixPreCommand Condition="'$(WindowsShell)' == 'true'" Include="set &quot;SDK_DIR_NAME=$(SdkForWorkloadTestingDirName)&quot;" />
-    <HelixPreCommand Condition="'$(WindowsShell)' != 'true'" Include="export &quot;SDK_DIR_NAME=$(SdkForWorkloadTestingDirName)&quot;" />
-
-    <HelixPreCommand Condition="'$(WindowsShell)' == 'true'" Include="set &quot;DOTNET_SKIP_FIRST_TIME_EXPERIENCE=1&quot;" />
-    <HelixPreCommand Condition="'$(WindowsShell)' != 'true'" Include="export &quot;DOTNET_SKIP_FIRST_TIME_EXPERIENCE=1&quot;" />
+    <HelixPreCommand Condition="'$(WindowsShell)' == 'true'" Include="$(EnvVarCommand) &quot;BUILT_NUGETS_PATH=%HELIX_CORRELATION_PAYLOAD%/built-nugets&quot;" />
+    <HelixPreCommand Condition="'$(WindowsShell)' != 'true'" Include="$(EnvVarCommand) &quot;BUILT_NUGETS_PATH=$HELIX_CORRELATION_PAYLOAD/built-nugets&quot;" />
 
-    <HelixPreCommand Condition="'$(WindowsShell)' == 'true'" Include="set &quot;DOTNET_SKIP_WORKLOAD_INTEGRITY_CHECK=1&quot;" />
-    <HelixPreCommand Condition="'$(WindowsShell)' != 'true'" Include="export &quot;DOTNET_SKIP_WORKLOAD_INTEGRITY_CHECK=1&quot;" />
+    <HelixPreCommand Include="$(EnvVarCommand) &quot;XUnitTraitArg=$(_XUnitTraitArg)&quot;" />
+    <HelixPreCommand Include="$(EnvVarCommand) &quot;SDK_DIR_NAME=$(SdkForWorkloadTestingDirName)&quot;" />
+    <HelixPreCommand Include="$(EnvVarCommand) &quot;DOTNET_SKIP_FIRST_TIME_EXPERIENCE=1&quot;" />
+    <HelixPreCommand Include="$(EnvVarCommand) &quot;DOTNET_SKIP_WORKLOAD_INTEGRITY_CHECK=1&quot;" />
   </ItemGroup>
 
   <Target Name="_AddWorkItemsForBuildWasmApps" Condition="'$(Scenario)' == 'BuildWasmApps'">
@@ -53,8 +49,7 @@
     <ItemGroup>
       <HelixWorkItem Include="@(BuildWasmApps_PerJobList->'$(WorkItemPrefix)%(Identity)')" Condition="'$(TestUsingWorkloads)' == 'true' and '$(WasmFingerprintAssets)' == 'true' and '$(WasmBundlerFriendlyBootConfig)' == 'false'">
         <PayloadArchive>$(_BuildWasmAppsPayloadArchive)</PayloadArchive>
-        <PreCommands Condition="'$(OS)' == 'Windows_NT'">set &quot;HELIX_XUNIT_ARGS=-class %(Identity)&quot;</PreCommands>
-        <PreCommands Condition="'$(OS)' != 'Windows_NT'">export &quot;HELIX_XUNIT_ARGS=-class %(Identity)&quot;</PreCommands>
+        <PreCommands>$(EnvVarCommand) &quot;HELIX_XUNIT_ARGS=-class %(Identity)&quot;</PreCommands>
         <Command>$(HelixCommand)</Command>
         <Timeout>$(_workItemTimeout)</Timeout>
       </HelixWorkItem>

From 08a0e0947c5551c8c2a239a13f4c13d83155c97a Mon Sep 17 00:00:00 2001
From: Ilona Tomkowicz <32700855+ilonatommy@users.noreply.github.com>
Date: Mon, 24 Nov 2025 13:10:27 +0000
Subject: [PATCH 4/4] Fix syntax.

---
 src/libraries/sendtohelix-browser.targets | 24 +++++++++++------------
 src/libraries/sendtohelix-wasi.targets    |  4 ++--
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/src/libraries/sendtohelix-browser.targets b/src/libraries/sendtohelix-browser.targets
index d3a92fbac1e7bf..fe3efe43b7a095 100644
--- a/src/libraries/sendtohelix-browser.targets
+++ b/src/libraries/sendtohelix-browser.targets
@@ -98,19 +98,19 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(WindowsShell)' != 'true'">
-    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="(EnvVarCommand) PATH=$HELIX_CORRELATION_PAYLOAD/$(ChromeDriverDirName):$PATH" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="(EnvVarCommand) PATH=$HELIX_CORRELATION_PAYLOAD/$(ChromeDirName):$PATH" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="(EnvVarCommand) PATH=$HELIX_CORRELATION_PAYLOAD/$(GeckoDriverDirName):$PATH" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="(EnvVarCommand) PATH=$HELIX_CORRELATION_PAYLOAD/$(FirefoxDirName):$PATH" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnV8)' == 'true'" Include="(EnvVarCommand) V8_PATH_FOR_TESTS=$HELIX_CORRELATION_PAYLOAD/$(V8DirName)/$(V8BinaryName)" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="$(EnvVarCommand) PATH=$HELIX_CORRELATION_PAYLOAD/$(ChromeDriverDirName):$PATH" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="$(EnvVarCommand) PATH=$HELIX_CORRELATION_PAYLOAD/$(ChromeDirName):$PATH" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="$(EnvVarCommand) PATH=$HELIX_CORRELATION_PAYLOAD/$(GeckoDriverDirName):$PATH" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="$(EnvVarCommand) PATH=$HELIX_CORRELATION_PAYLOAD/$(FirefoxDirName):$PATH" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnV8)' == 'true'" Include="$(EnvVarCommand) V8_PATH_FOR_TESTS=$HELIX_CORRELATION_PAYLOAD/$(V8DirName)/$(V8BinaryName)" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(WindowsShell)' == 'true'">
-    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\$(ChromeDriverDirName)%3B%PATH%" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\$(ChromeDirName)%3B%PATH%" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\$(GeckoDriverDirName)%3B%PATH%" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\$(FirefoxDirName)%3B%PATH%" />
-    <HelixPreCommand Condition="'$(NeedsToRunOnV8)' == 'true'" Include="(EnvVarCommand) V8_PATH_FOR_TESTS=%HELIX_CORRELATION_PAYLOAD%\$(V8DirName)\$(V8BinaryName)" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="$(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\$(ChromeDriverDirName)%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnChrome)' == 'true'" Include="$(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\$(ChromeDirName)%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="$(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\$(GeckoDriverDirName)%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnFirefox)' == 'true'" Include="$(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\$(FirefoxDirName)%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsToRunOnV8)' == 'true'" Include="$(EnvVarCommand) V8_PATH_FOR_TESTS=%HELIX_CORRELATION_PAYLOAD%\$(V8DirName)\$(V8BinaryName)" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(NeedsEMSDKNode)' == 'true' and '$(WindowsShell)' != 'true'">
@@ -125,8 +125,8 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(NeedsEMSDKNode)' == 'true' and '$(WindowsShell)' == 'true'">
-    <HelixPreCommand Include="for /f %%i in ('dir $(_HelixLocalNodePath) /b') do (EnvVarCommand) _HELIX_NODEJS_VERSION=%%i" />
-    <HelixPreCommand Include="(EnvVarCommand) PATH=$(_HelixLocalNodePath)/%_HELIX_NODEJS_VERSION%/bin%3B%PATH%" />
+    <HelixPreCommand Include="for /f %%i in ('dir $(_HelixLocalNodePath) /b') do $(EnvVarCommand) _HELIX_NODEJS_VERSION=%%i" />
+    <HelixPreCommand Include="$(EnvVarCommand) PATH=$(_HelixLocalNodePath)/%_HELIX_NODEJS_VERSION%/bin%3B%PATH%" />
   </ItemGroup>
 
   <PropertyGroup Condition="'$(Scenario)' == 'BuildWasmApps'">
diff --git a/src/libraries/sendtohelix-wasi.targets b/src/libraries/sendtohelix-wasi.targets
index a4aefcfdeab107..44500dfaad7b7b 100644
--- a/src/libraries/sendtohelix-wasi.targets
+++ b/src/libraries/sendtohelix-wasi.targets
@@ -74,8 +74,8 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(WindowsShell)' == 'true'">
-    <HelixPreCommand Condition="'$(NeedsWasmtime)' == 'true'" Include="(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\wasmtime%3B%PATH%" />
-    <HelixPreCommand Condition="'$(NeedsWasiSdk)' == 'true'" Include="(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\build\wasi-sdk\bin%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsWasmtime)' == 'true'" Include="$(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\wasmtime%3B%PATH%" />
+    <HelixPreCommand Condition="'$(NeedsWasiSdk)' == 'true'" Include="$(EnvVarCommand) PATH=%HELIX_CORRELATION_PAYLOAD%\build\wasi-sdk\bin%3B%PATH%" />
   </ItemGroup>
 
   <PropertyGroup Condition="'$(Scenario)' == 'BuildWasmApps'">