Fix bug in Batch files when checking for unset variables

PiperOrigin-RevId: 997224152
Change-Id: I8d032522a296b59b59e2ed7246b908ccf0bb471e

ci/windows_clangcl_bazel.bat

diff --git a/ci/windows_clangcl_bazel.bat b/ci/windows_clangcl_bazel.bat
index 42be0f7..e196d3b 100755
--- a/ci/windows_clangcl_bazel.bat
+++ b/ci/windows_clangcl_bazel.bat
@@ -32,15 +32,15 @@
 :: Set the standard version, [c++17|c++20|c++latest]
 :: https://msdn.microsoft.com/en-us/library/mt490614.aspx
 :: The default is c++17 if not set on command line.
-IF "%STD%"=="" SET STD=c++17
+IF NOT DEFINED STD SET STD=c++17
 
 :: Set the compilation_mode (fastbuild|opt|dbg)
 :: https://docs.bazel.build/versions/master/user-manual.html#flag--compilation_mode
 :: The default is fastbuild
-IF "%COMPILATION_MODE%"=="" SET COMPILATION_MODE=fastbuild
+IF NOT DEFINED COMPILATION_MODE SET COMPILATION_MODE=fastbuild
 
 :: Copy the alternate option file, if specified.
-IF NOT "%ALTERNATE_OPTIONS%"=="" copy %ALTERNATE_OPTIONS% absl\base\options.h
+IF DEFINED ALTERNATE_OPTIONS copy %ALTERNATE_OPTIONS% absl\base\options.h
 
 :: To upgrade Bazel, first download a new binary from
 :: https://github.com/bazelbuild/bazel/releases and copy it to
@@ -49,11 +49,11 @@
 :: TODO(absl-team): Remove -Wno-microsoft-cast
 %KOKORO_GFILE_DIR%\bazel-9.1.0-windows-x86_64.exe ^
   test ... ^
-  --compilation_mode=%COMPILATION_MODE% ^
+  --compilation_mode="%COMPILATION_MODE%" ^
   --compiler=clang-cl ^
   --copt=/WX ^
   --copt=-Wno-microsoft-cast ^
-  --cxxopt=/std:%STD% ^
+  --cxxopt="/std:%STD%" ^
   --define=absl=1 ^
   --enable_bzlmod=true ^
   --extra_execution_platforms=//:x64_windows-clang-cl ^

ci/windows_msvc_bazel.bat

diff --git a/ci/windows_msvc_bazel.bat b/ci/windows_msvc_bazel.bat
index a4bd3d7..4cb0870 100755
--- a/ci/windows_msvc_bazel.bat
+++ b/ci/windows_msvc_bazel.bat
@@ -29,24 +29,24 @@
 :: Set the standard version, [c++17|c++latest]
 :: https://msdn.microsoft.com/en-us/library/mt490614.aspx
 :: The default is c++17 if not set on command line.
-IF "%STD%"=="" SET STD=c++17
+IF NOT DEFINED STD SET STD=c++17
 
 :: Set the compilation_mode (fastbuild|opt|dbg)
 :: https://docs.bazel.build/versions/master/user-manual.html#flag--compilation_mode
 :: The default is fastbuild
-IF "%COMPILATION_MODE%"=="" SET COMPILATION_MODE=fastbuild
+IF NOT DEFINED COMPILATION_MODE SET COMPILATION_MODE=fastbuild
 
 :: Copy the alternate option file, if specified.
-IF NOT "%ALTERNATE_OPTIONS%"=="" copy %ALTERNATE_OPTIONS% absl\base\options.h
+IF DEFINED ALTERNATE_OPTIONS copy %ALTERNATE_OPTIONS% absl\base\options.h
 
 :: To upgrade Bazel, first download a new binary from
 :: https://github.com/bazelbuild/bazel/releases and copy it to
 :: /google/data/rw/teams/absl/kokoro/windows.
 "%KOKORO_GFILE_DIR%\bazel-9.1.0-windows-x86_64.exe" ^
   test ... ^
-  --compilation_mode=%COMPILATION_MODE% ^
+  --compilation_mode="%COMPILATION_MODE%" ^
   --copt=/WX ^
-  --cxxopt=/std:%STD% ^
+  --cxxopt="/std:%STD%" ^
   --define=absl=1 ^
   --enable_bzlmod=true ^
   --keep_going ^

ci/windows_msvc_cmake.bat

diff --git a/ci/windows_msvc_cmake.bat b/ci/windows_msvc_cmake.bat
index 88d6efe..a35dcec 100755
--- a/ci/windows_msvc_cmake.bat
+++ b/ci/windows_msvc_cmake.bat
@@ -43,13 +43,13 @@
 :: Set the standard version, [c++17|c++latest]
 :: https://msdn.microsoft.com/en-us/library/mt490614.aspx
 :: The default is c++17 if not set on command line.
-IF "%STD%"=="" SET STD=17
+IF NOT DEFINED STD SET STD=17
 
-IF "%ABSL_CMAKE_BUILD_SHARED%"=="" SET ABSL_CMAKE_BUILD_SHARED=OFF
+IF NOT DEFINED ABSL_CMAKE_BUILD_SHARED SET ABSL_CMAKE_BUILD_SHARED=OFF
 
-IF "%ABSL_CMAKE_BUILD_TYPE%"=="" SET ABSL_CMAKE_BUILD_TYPE=Debug
+IF NOT DEFINED ABSL_CMAKE_BUILD_TYPE SET ABSL_CMAKE_BUILD_TYPE=Debug
 
-IF "%ABSL_CMAKE_GENERATOR%"=="" SET "ABSL_CMAKE_GENERATOR=Visual Studio 17 2022"
+IF NOT DEFINED ABSL_CMAKE_GENERATOR SET "ABSL_CMAKE_GENERATOR=Visual Studio 17 2022"
 
 :: Change directory to the root of the project.
 CD %~dp0\..
@@ -64,9 +64,9 @@
 
 %CMAKE_BIN% ^
   -DABSL_BUILD_TESTING=ON ^
-  -DABSL_GOOGLETEST_DOWNLOAD_URL=%ABSL_GOOGLETEST_DOWNLOAD_URL% ^
-  -DBUILD_SHARED_LIBS=%ABSL_CMAKE_BUILD_SHARED% ^
-  -DCMAKE_CXX_STANDARD=%STD% ^
+  -DABSL_GOOGLETEST_DOWNLOAD_URL="%ABSL_GOOGLETEST_DOWNLOAD_URL%" ^
+  -DBUILD_SHARED_LIBS="%ABSL_CMAKE_BUILD_SHARED%" ^
+  -DCMAKE_CXX_STANDARD="%STD%" ^
   -G "%ABSL_CMAKE_GENERATOR%" ^
   ..
 IF %errorlevel% neq 0 EXIT /B 1