Add the TARGET_NAME generator expression.

It will be used as a preprocessing marker.

Source/cmDocumentGeneratorExpressions.h

@@ -26,6 +26,10 @@
   "strings which contain a '>' for example.\n"                          \
   "  $<COMMA>                  = A literal ','. Used to compare "       \
   "strings which contain a ',' for example.\n"                          \
+  "  $<TARGET_NAME:...>        = Marks ... as being the name of a "     \
+  "target.  This is required if exporting targets to multiple "         \
+  "dependent export sets.  The '...' must be a literal name of a "      \
+  "target- it may not contain generator expressions.\n"                 \
   "  $<INSTALL_INTERFACE:...>  = content of \"...\" when the property " \
   "is exported using install(EXPORT), and empty otherwise.\n"           \
   "  $<BUILD_INTERFACE:...>    = content of \"...\" when the property " \

Source/cmGeneratorExpressionEvaluator.cxx

@@ -376,6 +376,28 @@ static const struct TargetPropertyNode : public cmGeneratorExpressionNode
   }
 } targetPropertyNode;
 
+//----------------------------------------------------------------------------
+static const struct TargetNameNode : public cmGeneratorExpressionNode
+{
+  TargetNameNode() {}
+
+  virtual bool GeneratesContent() const { return true; }
+
+  virtual bool AcceptsSingleArbitraryContentParameter() const { return true; }
+  virtual bool RequiresLiteralInput() const { return true; }
+
+  std::string Evaluate(const std::vector<std::string> &parameters,
+                       cmGeneratorExpressionContext *,
+                       const GeneratorExpressionContent *,
+                       cmGeneratorExpressionDAGChecker *) const
+  {
+    return parameters.front();
+  }
+
+  virtual int NumExpectedParameters() const { return 1; }
+
+} targetNameNode;
+
 //----------------------------------------------------------------------------
 template<bool linker, bool soname>
 struct TargetFilesystemArtifactResultCreator
@@ -601,6 +623,8 @@ cmGeneratorExpressionNode* GetNode(const std::string &identifier)
     return &commaNode;
   else if (identifier == "TARGET_PROPERTY")
     return &targetPropertyNode;
+  else if (identifier == "TARGET_NAME")
+    return &targetNameNode;
   else if (identifier == "BUILD_INTERFACE")
     return &buildInterfaceNode;
   else if (identifier == "INSTALL_INTERFACE")

Tests/GeneratorExpression/CMakeLists.txt

@@ -87,6 +87,8 @@ add_custom_target(check-part2 ALL
     -Dtest_incomplete_21=$<BOOL:something$<ANGLE-R>
     -Dtest_build_interface=$<BUILD_INTERFACE:build>
     -Dtest_install_interface=$<INSTALL_INTERFACE:install>
+    -Dtest_target_name_1=$<TARGET_NAME:tgt,ok>
+    -Dtest_target_name_2=$<TARGET_NAME:tgt:ok>
     -P ${CMAKE_CURRENT_SOURCE_DIR}/check-part2.cmake
   COMMAND ${CMAKE_COMMAND} -E echo "check done (part 2 of 2)"
   VERBATIM

Tests/GeneratorExpression/check-part2.cmake

@@ -24,3 +24,5 @@ check(test_incomplete_20 "$<CONFIGURATION>")
 check(test_incomplete_21 "$<BOOL:something>")
 check(test_build_interface "build")
 check(test_install_interface "")
+check(test_target_name_1 "tgt,ok")
+check(test_target_name_2 "tgt:ok")

Tests/RunCMake/GeneratorExpression/BadTargetName-result.txt

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

Tests/RunCMake/GeneratorExpression/BadTargetName-stderr.txt

@@ -0,0 +1,8 @@
+CMake Error at BadTargetName.cmake:1 \(add_custom_target\):
+  Error evaluating generator expression:
+
+    \$<TARGET_NAME:\$<1:tgt>>
+
+  \$<TARGET_NAME> expression requires literal input.
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)$

Tests/RunCMake/GeneratorExpression/BadTargetName.cmake

@@ -0,0 +1,3 @@
+add_custom_target(check ALL COMMAND check
+  $<TARGET_NAME:$<1:tgt>>
+  VERBATIM)

Tests/RunCMake/GeneratorExpression/RunCMakeTest.cmake

@@ -6,3 +6,4 @@ run_cmake(BadAND)
 run_cmake(BadNOT)
 run_cmake(BadStrEqual)
 run_cmake(BadZero)
+run_cmake(BadTargetName)