if: Diagnose invalid argument in parentheses

Fixes: #26424

Source/cmConditionEvaluator.cxx

@@ -409,6 +409,9 @@ bool cmConditionEvaluator::HandleLevel0(cmArgumentList& newArgs,
       // now recursively invoke IsTrue to handle the values inside the
       // parenthetical expression
       auto const value = this->IsTrue(subExpr, errorString, status);
+      if (!errorString.empty()) {
+        return false;
+      }
       *arg = cmExpandedCommandArgument(bool2string(value), true);
       argOpen = std::next(arg);
       // remove the now evaluated parenthetical expression

Tests/RunCMake/if/InvalidArgumentInParenthesis-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/if/InvalidArgumentInParenthesis-stderr.txt

@@ -0,0 +1,8 @@
+^CMake Error at InvalidArgumentInParenthesis\.cmake:1 \(if\):
+  if given arguments:
+
+    "\(" "A" "B" "\)" "OR" "\(" "" "\)"
+
+  Unknown arguments specified
+Call Stack \(most recent call first\):
+  CMakeLists\.txt:3 \(include\)$

Tests/RunCMake/if/InvalidArgumentInParenthesis.cmake

@@ -0,0 +1,5 @@
+if((A B) OR ("$ENV{NOT_AN_ENV_VARIABLE}"))
+  message(STATUS "Invalid evaluated to TRUE")
+else()
+  message(STATUS "Invalid evaluated to FALSE")
+endif()

Tests/RunCMake/if/RunCMakeTest.cmake

@@ -1,6 +1,7 @@
 include(RunCMake)
 
 run_cmake(InvalidArgument1)
+run_cmake(InvalidArgumentInParenthesis)
 run_cmake(exists)
 if(NOT MSYS)
   # permissions and symbolic links are broken on MSYS

Tests/RunCMake/while/InvalidArgument-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/while/InvalidArgument-stderr.txt

@@ -0,0 +1,8 @@
+^CMake Error at InvalidArgument\.cmake:2 \(while\):
+  while\(\) given incorrect arguments:
+
+    "\(" "A" "B" "\)" "OR" "\(" "" "\)"
+
+  Unknown arguments specified
+Call Stack \(most recent call first\):
+  CMakeLists\.txt:3 \(include\)$

Tests/RunCMake/while/InvalidArgument.cmake

@@ -0,0 +1,6 @@
+cmake_policy(SET CMP0130 NEW)
+while((A B) OR ("$ENV{NOT_AN_ENV_VARIABLE}"))
+  message(STATUS "Invalid evaluated to TRUE")
+  return()
+endwhile()
+message(STATUS "Invalid evaluated to FALSE")

Tests/RunCMake/while/RunCMakeTest.cmake

@@ -1,6 +1,7 @@
 include(RunCMake)
 
 run_cmake(MissingArgument)
+run_cmake(InvalidArgument)
 run_cmake(EndMissing)
 run_cmake(EndMismatch)
 run_cmake(EndAlone)