Merge topic 'dev/support-substring-negative-indices'

36cb701 allow STRING(SUBSTRING) work with length -1 as "rest of the string"

Source/cmStringCommand.cxx

@@ -606,7 +606,7 @@ bool cmStringCommand::HandleSubstringCommand(std::vector<std::string> const&
     return false;
     }
   int leftOverLength = intStringLength - begin;
-  if ( end < 0 || end > leftOverLength )
+  if ( end < -1 || end > leftOverLength )
     {
     cmOStringStream ostr;
     ostr << "end index: " << end << " is out of range " << 0 << " - "

Tests/StringFileTest/CMakeLists.txt

@@ -256,3 +256,27 @@ endif()
 if(NOT "${var_b}" STREQUAL "x")
   message(FATAL_ERROR "count incorrect \"b\": [${var_b}]")
 endif()
+
+# Test SUBSTRING command
+SET(ST_INPUTSTRING "0123456789")
+STRING(SUBSTRING ${ST_INPUTSTRING} 3 0 ST_EMPTY)
+STRING(SUBSTRING ${ST_INPUTSTRING} 1 1 ST_ONE)
+STRING(SUBSTRING ${ST_INPUTSTRING} 0 10 ST_ALL)
+STRING(SUBSTRING ${ST_INPUTSTRING} 0 -1 ST_ALL_MINUS)
+STRING(SUBSTRING ${ST_INPUTSTRING} 9 -1 ST_NINE)
+
+IF(ST_EMPTY)
+  MESSAGE(SEND_ERROR "SUBSTRING with length 0 does not return an empty string")
+ENDIF(ST_EMPTY)
+IF(NOT ST_ONE STREQUAL "1")
+  MESSAGE(SEND_ERROR "SUBSTING command does not cut the correct selected character, was \"" ${ST_ONE} "\", should be \"1\"")
+ENDIF(NOT ST_ONE STREQUAL "1")
+IF(NOT ST_INPUTSTRING STREQUAL ST_ALL)
+  MESSAGE(SEND_ERROR "SUBSTRING does not return the whole string when selected with length")
+ENDIF(NOT ST_INPUTSTRING STREQUAL ST_ALL)
+IF(NOT ST_INPUTSTRING STREQUAL ST_ALL_MINUS)
+  MESSAGE(SEND_ERROR "SUBSTRING does not return the whole string when selected with -1")
+ENDIF(NOT ST_INPUTSTRING STREQUAL ST_ALL_MINUS)
+IF(NOT ST_NINE STREQUAL "9")
+  MESSAGE(SEND_ERROR "SUBSTRING does not return the tail when selected with -1")
+ENDIF(NOT ST_NINE STREQUAL "9")