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, 3 insertions, 9 deletions

diff --git a/Source/cmFindBase.cxx b/Source/cmFindBase.cxx
index 9bacfc4a31..191d7bb1bc 100644
--- a/Source/cmFindBase.cxx
+++ b/Source/cmFindBase.cxx
@@ -189,9 +189,7 @@ void cmFindBase::FillCMakeEnvironmentPath()
   cmSearchPath& paths = this->LabeledPaths[PathLabel::CMakeEnvironment];
 
   // Add CMAKE_*_PATH environment variables
-  std::string var = "CMAKE_";
-  var += this->CMakePathName;
-  var += "_PATH";
+  std::string var = cmStrCat("CMAKE_", this->CMakePathName, "_PATH");
   paths.AddEnvPrefixPath("CMAKE_PREFIX_PATH");
   paths.AddEnvPath(var);
 
@@ -223,9 +221,7 @@ void cmFindBase::FillCMakeVariablePath()
   // Add CMake variables of the same name as the previous environment
   // variables CMAKE_*_PATH to be used most of the time with -D
   // command line options
-  std::string var = "CMAKE_";
-  var += this->CMakePathName;
-  var += "_PATH";
+  std::string var = cmStrCat("CMAKE_", this->CMakePathName, "_PATH");
   paths.AddCMakePrefixPath("CMAKE_PREFIX_PATH");
   paths.AddCMakePath(var);
 
@@ -257,9 +253,7 @@ void cmFindBase::FillCMakeSystemVariablePath()
 {
   cmSearchPath& paths = this->LabeledPaths[PathLabel::CMakeSystem];
 
-  std::string var = "CMAKE_SYSTEM_";
-  var += this->CMakePathName;
-  var += "_PATH";
+  std::string var = cmStrCat("CMAKE_SYSTEM_", this->CMakePathName, "_PATH");
   paths.AddCMakePrefixPath("CMAKE_SYSTEM_PREFIX_PATH");
   paths.AddCMakePath(var);