ClearMatches: Only clear matches which were actually set

ClearMatches was clearing many variables which were never set in the
first place. Instead, store how many matches were made last time and
only clear those. It is moved to the cmMakefile class since it is a
common utility used by multiple commands.

Source/cmIfCommand.cxx

@@ -595,7 +595,7 @@ namespace
         {
         def = cmIfCommand::GetVariableOrString(*arg, makefile);
         const char* rex = (argP2)->c_str();
-        cmStringCommand::ClearMatches(makefile);
+        makefile->ClearMatches();
         cmsys::RegularExpression regEntry;
         if ( !regEntry.compile(rex) )
           {
@@ -607,7 +607,7 @@ namespace
           }
         if (regEntry.find(def))
           {
-          cmStringCommand::StoreMatches(makefile, regEntry);
+          makefile->StoreMatches(regEntry);
           *arg = "1";
           }
         else

Source/cmMakefile.cxx

@@ -148,6 +148,8 @@ cmMakefile::cmMakefile(): Internal(new Internals)
   this->Initialize();
   this->PreOrder = false;
   this->GeneratingBuildSystem = false;
+
+  this->NumLastMatches = 0;
 }
 
 cmMakefile::cmMakefile(const cmMakefile& mf): Internal(new Internals)
@@ -196,6 +198,8 @@ cmMakefile::cmMakefile(const cmMakefile& mf): Internal(new Internals)
   this->CheckSystemVars = mf.CheckSystemVars;
   this->ListFileStack = mf.ListFileStack;
   this->OutputToSource = mf.OutputToSource;
+
+  this->NumLastMatches = mf.NumLastMatches;
 }
 
 //----------------------------------------------------------------------------
@@ -4328,6 +4332,42 @@ std::vector<cmSourceFile*> cmMakefile::GetQtUiFilesWithOptions() const
   return this->QtUiFilesWithOptions;
 }
 
+//----------------------------------------------------------------------------
+void cmMakefile::ClearMatches()
+{
+  std::stringstream sstr;
+  for (unsigned int i=0; i<this->NumLastMatches; i++)
+    {
+    sstr.str("");
+    sstr << "CMAKE_MATCH_" << i;
+    std::string const& name = sstr.str();
+    std::string const& s = this->GetSafeDefinition(name);
+    if(!s.empty())
+      {
+      this->AddDefinition(name, "");
+      this->MarkVariableAsUsed(name);
+      }
+    }
+  this->NumLastMatches = 0;
+}
+
+//----------------------------------------------------------------------------
+void cmMakefile::StoreMatches(cmsys::RegularExpression& re)
+{
+  for (unsigned int i=0; i<10; i++)
+    {
+    std::string m = re.match(i);
+    if(m.size() > 0)
+      {
+      char name[128];
+      sprintf(name, "CMAKE_MATCH_%d", i);
+      this->AddDefinition(name, re.match(i).c_str());
+      this->MarkVariableAsUsed(name);
+      this->NumLastMatches = i + 1;
+      }
+    }
+}
+
 //----------------------------------------------------------------------------
 cmPolicies::PolicyStatus
 cmMakefile::GetPolicyStatus(cmPolicies::PolicyID id) const

Source/cmMakefile.h

@@ -889,6 +889,9 @@ public:
                                 const std::string& feature,
                                 std::string *error = 0) const;
 
+  void ClearMatches();
+  void StoreMatches(cmsys::RegularExpression& re);
+
 protected:
   // add link libraries and directories to the target
   void AddGlobalLinkInformation(const std::string& name, cmTarget& target);
@@ -1065,6 +1068,8 @@ private:
                                cmSourceFile* source);
 
   std::vector<cmSourceFile*> QtUiFilesWithOptions;
+
+  unsigned int NumLastMatches;
 };
 
 //----------------------------------------------------------------------------

Source/cmStringCommand.cxx

@@ -305,7 +305,7 @@ bool cmStringCommand::RegexMatch(std::vector<std::string> const& args)
     input += args[i];
     }
 
-  this->ClearMatches(this->Makefile);
+  this->Makefile->ClearMatches();
   // Compile the regular expression.
   cmsys::RegularExpression re;
   if(!re.compile(regex.c_str()))
@@ -320,7 +320,7 @@ bool cmStringCommand::RegexMatch(std::vector<std::string> const& args)
   std::string output;
   if(re.find(input.c_str()))
     {
-    this->StoreMatches(this->Makefile, re);
+    this->Makefile->StoreMatches(re);
     std::string::size_type l = re.start();
     std::string::size_type r = re.end();
     if(r-l == 0)
@@ -354,7 +354,7 @@ bool cmStringCommand::RegexMatchAll(std::vector<std::string> const& args)
     input += args[i];
     }
 
-  this->ClearMatches(this->Makefile);
+  this->Makefile->ClearMatches();
   // Compile the regular expression.
   cmsys::RegularExpression re;
   if(!re.compile(regex.c_str()))
@@ -371,7 +371,7 @@ bool cmStringCommand::RegexMatchAll(std::vector<std::string> const& args)
   const char* p = input.c_str();
   while(re.find(p))
     {
-    this->StoreMatches(this->Makefile, re);
+    this->Makefile->StoreMatches(re);
     std::string::size_type l = re.start();
     std::string::size_type r = re.end();
     if(r-l == 0)
@@ -458,7 +458,7 @@ bool cmStringCommand::RegexReplace(std::vector<std::string> const& args)
     input += args[i];
     }
 
-  this->ClearMatches(this->Makefile);
+  this->Makefile->ClearMatches();
   // Compile the regular expression.
   cmsys::RegularExpression re;
   if(!re.compile(regex.c_str()))
@@ -475,7 +475,7 @@ bool cmStringCommand::RegexReplace(std::vector<std::string> const& args)
   std::string::size_type base = 0;
   while(re.find(input.c_str()+base))
     {
-    this->StoreMatches(this->Makefile, re);
+    this->Makefile->StoreMatches(re);
     std::string::size_type l2 = re.start();
     std::string::size_type r = re.end();
 
@@ -535,38 +535,6 @@ bool cmStringCommand::RegexReplace(std::vector<std::string> const& args)
   return true;
 }
 
-//----------------------------------------------------------------------------
-void cmStringCommand::ClearMatches(cmMakefile* mf)
-{
-  for (unsigned int i=0; i<10; i++)
-    {
-    char name[128];
-    sprintf(name, "CMAKE_MATCH_%d", i);
-    const char* s = mf->GetDefinition(name);
-    if(s && *s != 0)
-      {
-      mf->AddDefinition(name, "");
-      mf->MarkVariableAsUsed(name);
-      }
-    }
-}
-
-//----------------------------------------------------------------------------
-void cmStringCommand::StoreMatches(cmMakefile* mf,cmsys::RegularExpression& re)
-{
-  for (unsigned int i=0; i<10; i++)
-    {
-    std::string m = re.match(i);
-    if(m.size() > 0)
-      {
-      char name[128];
-      sprintf(name, "CMAKE_MATCH_%d", i);
-      mf->AddDefinition(name, re.match(i).c_str());
-      mf->MarkVariableAsUsed(name);
-      }
-    }
-}
-
 //----------------------------------------------------------------------------
 bool cmStringCommand::HandleFindCommand(std::vector<std::string> const&
                                            args)

Source/cmStringCommand.h

@@ -53,8 +53,6 @@ public:
   virtual std::string GetName() const { return "string";}
 
   cmTypeMacro(cmStringCommand, cmCommand);
-  static void ClearMatches(cmMakefile* mf);
-  static void StoreMatches(cmMakefile* mf, cmsys::RegularExpression& re);
 protected:
   bool HandleConfigureCommand(std::vector<std::string> const& args);
   bool HandleAsciiCommand(std::vector<std::string> const& args);