Source sweep: Use cmStrCat for string concatenation

This patch is generated by a python script that uses regular expressions to
search for string concatenation patterns of the kind

```
std::string str = <ARG0>;
str += <ARG1>;
str += <ARG2>;
...
```

and replaces them with a single `cmStrCat` call

```
std::string str = cmStrCat(<ARG0>, <ARG1>, <ARG2>, ...);
```

If any `<ARGX>` is itself a concatenated string of the kind

```
a + b + c + ...;
```

then `<ARGX>` is split into multiple arguments for the `cmStrCat` call.

If there's a sequence of literals in the `<ARGX>`, then all literals in the
sequence are concatenated and merged into a single literal argument for
the `cmStrCat` call.

Single character strings are converted to single char arguments for
the `cmStrCat` call.

`std::to_string(...)` wrappings are removed from `cmStrCat` arguments,
because it supports numeric types as well as string types.

`arg.substr(x)` arguments to `cmStrCat` are replaced with
`cm::string_view(arg).substr(x)`

1 files changed, 33 insertions, 59 deletions

diff --git a/Source/cmNinjaNormalTargetGenerator.cxx b/Source/cmNinjaNormalTargetGenerator.cxx
index 15c6580..2841245 100644
--- a/Source/cmNinjaNormalTargetGenerator.cxx
+++ b/Source/cmNinjaNormalTargetGenerator.cxx
@@ -218,8 +218,7 @@ void cmNinjaNormalTargetGenerator::WriteDeviceLinkRule(bool useResponseFile)
     const char* val = this->GetLocalGenerator()->GetRuleLauncher(
       this->GetGeneratorTarget(), "RULE_LAUNCH_LINK");
     if (val && *val) {
-      launcher = val;
-      launcher += " ";
+      launcher = cmStrCat(val, ' ');
     }
 
     std::unique_ptr<cmRulePlaceholderExpander> rulePlaceholderExpander(
@@ -239,16 +238,10 @@ void cmNinjaNormalTargetGenerator::WriteDeviceLinkRule(bool useResponseFile)
     rule.Command = this->GetLocalGenerator()->BuildCommandLine(linkCmds);
 
     // Write the linker rule with response file if needed.
-    rule.Comment = "Rule for linking ";
-    rule.Comment += this->TargetLinkLanguage;
-    rule.Comment += " ";
-    rule.Comment += this->GetVisibleTypeName();
-    rule.Comment += ".";
-    rule.Description = "Linking ";
-    rule.Description += this->TargetLinkLanguage;
-    rule.Description += " ";
-    rule.Description += this->GetVisibleTypeName();
-    rule.Description += " $TARGET_FILE";
+    rule.Comment = cmStrCat("Rule for linking ", this->TargetLinkLanguage, ' ',
+                            this->GetVisibleTypeName(), '.');
+    rule.Description = cmStrCat("Linking ", this->TargetLinkLanguage, ' ',
+                                this->GetVisibleTypeName(), " $TARGET_FILE");
     rule.Restat = "$RESTAT";
 
     this->GetGlobalGenerator()->AddRule(rule);
@@ -282,8 +275,7 @@ void cmNinjaNormalTargetGenerator::WriteLinkRule(bool useResponseFile)
 
     std::string responseFlag;
 
-    std::string cmakeVarLang = "CMAKE_";
-    cmakeVarLang += this->TargetLinkLanguage;
+    std::string cmakeVarLang = cmStrCat("CMAKE_", this->TargetLinkLanguage);
 
     // build response file name
     std::string cmakeLinkVar = cmakeVarLang + "_RESPONSE_FILE_LINK_FLAG";
@@ -357,8 +349,7 @@ void cmNinjaNormalTargetGenerator::WriteLinkRule(bool useResponseFile)
     const char* val = this->GetLocalGenerator()->GetRuleLauncher(
       this->GetGeneratorTarget(), "RULE_LAUNCH_LINK");
     if (val && *val) {
-      launcher = val;
-      launcher += " ";
+      launcher = cmStrCat(val, ' ');
     }
 
     std::unique_ptr<cmRulePlaceholderExpander> rulePlaceholderExpander(
@@ -380,16 +371,10 @@ void cmNinjaNormalTargetGenerator::WriteLinkRule(bool useResponseFile)
     rule.Command = this->GetLocalGenerator()->BuildCommandLine(linkCmds);
 
     // Write the linker rule with response file if needed.
-    rule.Comment = "Rule for linking ";
-    rule.Comment += this->TargetLinkLanguage;
-    rule.Comment += " ";
-    rule.Comment += this->GetVisibleTypeName();
-    rule.Comment += ".";
-    rule.Description = "Linking ";
-    rule.Description += this->TargetLinkLanguage;
-    rule.Description += " ";
-    rule.Description += this->GetVisibleTypeName();
-    rule.Description += " $TARGET_FILE";
+    rule.Comment = cmStrCat("Rule for linking ", this->TargetLinkLanguage, ' ',
+                            this->GetVisibleTypeName(), '.');
+    rule.Description = cmStrCat("Linking ", this->TargetLinkLanguage, ' ',
+                                this->GetVisibleTypeName(), " $TARGET_FILE");
     rule.Restat = "$RESTAT";
     this->GetGlobalGenerator()->AddRule(rule);
   }
@@ -467,19 +452,19 @@ std::vector<std::string> cmNinjaNormalTargetGenerator::ComputeLinkCmd()
     if (linkCmd) {
       std::string linkCmdStr = linkCmd;
       if (this->GetGeneratorTarget()->HasImplibGNUtoMS(this->ConfigName)) {
-        std::string ruleVar = "CMAKE_";
-        ruleVar += this->GeneratorTarget->GetLinkerLanguage(this->ConfigName);
-        ruleVar += "_GNUtoMS_RULE";
+        std::string ruleVar = cmStrCat(
+          "CMAKE_", this->GeneratorTarget->GetLinkerLanguage(this->ConfigName),
+          "_GNUtoMS_RULE");
         if (const char* rule = this->Makefile->GetDefinition(ruleVar)) {
           linkCmdStr += rule;
         }
       }
       cmExpandList(linkCmdStr, linkCmds);
       if (this->GetGeneratorTarget()->GetPropertyAsBool("LINK_WHAT_YOU_USE")) {
-        std::string cmakeCommand =
+        std::string cmakeCommand = cmStrCat(
           this->GetLocalGenerator()->ConvertToOutputFormat(
-            cmSystemTools::GetCMakeCommand(), cmLocalGenerator::SHELL);
-        cmakeCommand += " -E __run_co_compile --lwyu=";
+            cmSystemTools::GetCMakeCommand(), cmLocalGenerator::SHELL),
+          " -E __run_co_compile --lwyu=");
         cmGeneratorTarget& gt = *this->GetGeneratorTarget();
         const std::string cfgName = this->GetConfigName();
         std::string targetOutputReal = this->ConvertToNinjaPath(
@@ -502,9 +487,8 @@ std::vector<std::string> cmNinjaNormalTargetGenerator::ComputeLinkCmd()
       }
       // TODO: Use ARCHIVE_APPEND for archives over a certain size.
       {
-        std::string linkCmdVar = "CMAKE_";
-        linkCmdVar += this->TargetLinkLanguage;
-        linkCmdVar += "_ARCHIVE_CREATE";
+        std::string linkCmdVar =
+          cmStrCat("CMAKE_", this->TargetLinkLanguage, "_ARCHIVE_CREATE");
 
         linkCmdVar = this->GeneratorTarget->GetFeatureSpecificLinkRuleVariable(
           linkCmdVar, this->TargetLinkLanguage, this->GetConfigName());
@@ -513,9 +497,8 @@ std::vector<std::string> cmNinjaNormalTargetGenerator::ComputeLinkCmd()
         cmExpandList(linkCmd, linkCmds);
       }
       {
-        std::string linkCmdVar = "CMAKE_";
-        linkCmdVar += this->TargetLinkLanguage;
-        linkCmdVar += "_ARCHIVE_FINISH";
+        std::string linkCmdVar =
+          cmStrCat("CMAKE_", this->TargetLinkLanguage, "_ARCHIVE_FINISH");
 
         linkCmdVar = this->GeneratorTarget->GetFeatureSpecificLinkRuleVariable(
           linkCmdVar, this->TargetLinkLanguage, this->GetConfigName());
@@ -590,10 +573,8 @@ void cmNinjaNormalTargetGenerator::WriteDeviceLinkStatement()
 
   // Compute the comment.
   cmNinjaBuild build(this->LanguageLinkerDeviceRule());
-  build.Comment = "Link the ";
-  build.Comment += this->GetVisibleTypeName();
-  build.Comment += " ";
-  build.Comment += targetOutputReal;
+  build.Comment =
+    cmStrCat("Link the ", this->GetVisibleTypeName(), ' ', targetOutputReal);
 
   cmNinjaVars& vars = build.Variables;
 
@@ -728,13 +709,9 @@ void cmNinjaNormalTargetGenerator::WriteLinkStatement()
                                               outpath);
 
     // Calculate the output path
-    targetOutput = outpath;
-    targetOutput += "/";
-    targetOutput += this->TargetNames.Output;
+    targetOutput = cmStrCat(outpath, '/', this->TargetNames.Output);
     targetOutput = this->ConvertToNinjaPath(targetOutput);
-    targetOutputReal = outpath;
-    targetOutputReal += "/";
-    targetOutputReal += this->TargetNames.Real;
+    targetOutputReal = cmStrCat(outpath, '/', this->TargetNames.Real);
     targetOutputReal = this->ConvertToNinjaPath(targetOutputReal);
   } else if (gt->IsFrameworkOnApple()) {
     // Create the library framework.
@@ -757,10 +734,8 @@ void cmNinjaNormalTargetGenerator::WriteLinkStatement()
   cmNinjaVars& vars = linkBuild.Variables;
 
   // Compute the comment.
-  linkBuild.Comment = "Link the ";
-  linkBuild.Comment += this->GetVisibleTypeName();
-  linkBuild.Comment += " ";
-  linkBuild.Comment += targetOutputReal;
+  linkBuild.Comment =
+    cmStrCat("Link the ", this->GetVisibleTypeName(), ' ', targetOutputReal);
 
   // Compute outputs.
   linkBuild.Outputs.push_back(targetOutputReal);
@@ -990,11 +965,11 @@ void cmNinjaNormalTargetGenerator::WriteLinkStatement()
     std::string cmakeCommand =
       this->GetLocalGenerator()->ConvertToOutputFormat(
         cmSystemTools::GetCMakeCommand(), cmOutputConverter::SHELL);
-    std::string cmd = cmakeCommand;
-    cmd += " -E __create_def ";
-    cmd += this->GetLocalGenerator()->ConvertToOutputFormat(
-      mdi->DefFile, cmOutputConverter::SHELL);
-    cmd += " ";
+    std::string cmd =
+      cmStrCat(cmakeCommand, " -E __create_def ",
+               this->GetLocalGenerator()->ConvertToOutputFormat(
+                 mdi->DefFile, cmOutputConverter::SHELL),
+               ' ');
     std::string obj_list_file = mdi->DefFile + ".objs";
     cmd += this->GetLocalGenerator()->ConvertToOutputFormat(
       obj_list_file, cmOutputConverter::SHELL);
@@ -1039,8 +1014,7 @@ void cmNinjaNormalTargetGenerator::WriteLinkStatement()
     symlinkVars["POST_BUILD"] = postBuildCmdLine;
   }
 
-  std::string cmakeVarLang = "CMAKE_";
-  cmakeVarLang += this->TargetLinkLanguage;
+  std::string cmakeVarLang = cmStrCat("CMAKE_", this->TargetLinkLanguage);
 
   // build response file name
   std::string cmakeLinkVar = cmakeVarLang + "_RESPONSE_FILE_LINK_FLAG";