Split apart combined TUs

The compile time improvements from using combined TUs mostly isn't
worth the annoyance they cause with various IDE shortcuts, like
when switching between header and its impl. file.

Splitting them apart also fixes the issue of empty subdirs being
installed due to `foo/internal` folders that only contained the
combined TUs and no headers.

Closes #2457
Closes #2463

9 files changed, 220 insertions, 237 deletions

diff --git a/src/catch2/internal/catch_combined_tu.cpp b/src/catch2/internal/catch_combined_tu.cpp
deleted file mode 100644
index 601ac8e7..00000000
--- a/src/catch2/internal/catch_combined_tu.cpp
+++ /dev/null
@@ -1,237 +0,0 @@
-
-//              Copyright Catch2 Authors
-// Distributed under the Boost Software License, Version 1.0.
-//   (See accompanying file LICENSE_1_0.txt or copy at
-//        https://www.boost.org/LICENSE_1_0.txt)
-
-// SPDX-License-Identifier: BSL-1.0
-/** \file
- * This is a special TU that combines what would otherwise be a very
- * small top-level TUs into one bigger TU.
- *
- * The reason for this is compilation performance improvements by
- * avoiding reparsing headers for many small TUs, instead having this
- * one TU include bit more, but having it all parsed only once.
- *
- * To avoid heavy-tail problem with compilation times, each "subpart"
- * of Catch2 has its own combined TU like this.
- */
-
-
-////////////////////////////////////////////////////////
-// vvv formerly catch_tag_alias_autoregistrar.cpp vvv //
-////////////////////////////////////////////////////////
-
-#include <catch2/catch_tag_alias_autoregistrar.hpp>
-#include <catch2/internal/catch_compiler_capabilities.hpp>
-#include <catch2/interfaces/catch_interfaces_registry_hub.hpp>
-
-namespace Catch {
-
-    RegistrarForTagAliases::RegistrarForTagAliases(char const* alias, char const* tag, SourceLineInfo const& lineInfo) {
-        CATCH_TRY {
-            getMutableRegistryHub().registerTagAlias(alias, tag, lineInfo);
-        } CATCH_CATCH_ALL {
-            // Do not throw when constructing global objects, instead register the exception to be processed later
-            getMutableRegistryHub().registerStartupException();
-        }
-    }
-
-}
-
-
-//////////////////////////////////////////
-// vvv formerly catch_polyfills.cpp vvv //
-//////////////////////////////////////////
-
-#include <catch2/internal/catch_polyfills.hpp>
-#include <catch2/internal/catch_compiler_capabilities.hpp>
-#include <cmath>
-
-namespace Catch {
-
-#if !defined(CATCH_CONFIG_POLYFILL_ISNAN)
-    bool isnan(float f) {
-        return std::isnan(f);
-    }
-    bool isnan(double d) {
-        return std::isnan(d);
-    }
-#else
-    // For now we only use this for embarcadero
-    bool isnan(float f) {
-        return std::_isnan(f);
-    }
-    bool isnan(double d) {
-        return std::_isnan(d);
-    }
-#endif
-
-} // end namespace Catch
-
-
-////////////////////////////////////////////////////
-// vvv formerly catch_uncaught_exceptions.cpp vvv //
-////////////////////////////////////////////////////
-
-#include <catch2/internal/catch_compiler_capabilities.hpp>
-#include <catch2/internal/catch_uncaught_exceptions.hpp>
-#include <catch2/internal/catch_config_uncaught_exceptions.hpp>
-
-#include <exception>
-
-namespace Catch {
-    bool uncaught_exceptions() {
-#if defined(CATCH_CONFIG_DISABLE_EXCEPTIONS)
-        return false;
-#elif defined(CATCH_CONFIG_CPP17_UNCAUGHT_EXCEPTIONS)
-        return std::uncaught_exceptions() > 0;
-#else
-        return std::uncaught_exception();
-#endif
-  }
-} // end namespace Catch
-
-
-////////////////////////////////////////////
-// vvv formerly catch_errno_guard.cpp vvv //
-////////////////////////////////////////////
-#include <catch2/internal/catch_errno_guard.hpp>
-
-#include <cerrno>
-
-namespace Catch {
-        ErrnoGuard::ErrnoGuard():m_oldErrno(errno){}
-        ErrnoGuard::~ErrnoGuard() { errno = m_oldErrno; }
-}
-
-
-///////////////////////////////////////////
-// vvv formerly catch_decomposer.cpp vvv //
-///////////////////////////////////////////
-#include <catch2/internal/catch_decomposer.hpp>
-
-namespace Catch {
-
-    ITransientExpression::~ITransientExpression() = default;
-
-    void formatReconstructedExpression( std::ostream &os, std::string const& lhs, StringRef op, std::string const& rhs ) {
-        if( lhs.size() + rhs.size() < 40 &&
-                lhs.find('\n') == std::string::npos &&
-                rhs.find('\n') == std::string::npos )
-            os << lhs << ' ' << op << ' ' << rhs;
-        else
-            os << lhs << '\n' << op << '\n' << rhs;
-    }
-}
-
-
-///////////////////////////////////////////////////////////
-// vvv formerly catch_startup_exception_registry.cpp vvv //
-///////////////////////////////////////////////////////////
-#include <catch2/internal/catch_startup_exception_registry.hpp>
-#include <catch2/internal/catch_compiler_capabilities.hpp>
-
-namespace Catch {
-#if !defined(CATCH_CONFIG_DISABLE_EXCEPTIONS)
-    void StartupExceptionRegistry::add( std::exception_ptr const& exception ) noexcept {
-        CATCH_TRY {
-            m_exceptions.push_back(exception);
-        } CATCH_CATCH_ALL {
-            // If we run out of memory during start-up there's really not a lot more we can do about it
-            std::terminate();
-        }
-    }
-
-    std::vector<std::exception_ptr> const& StartupExceptionRegistry::getExceptions() const noexcept {
-        return m_exceptions;
-    }
-#endif
-
-} // end namespace Catch
-
-
-//////////////////////////////////////////////
-// vvv formerly catch_leak_detector.cpp vvv //
-//////////////////////////////////////////////
-#include <catch2/internal/catch_leak_detector.hpp>
-#include <catch2/interfaces/catch_interfaces_registry_hub.hpp>
-
-
-#ifdef CATCH_CONFIG_WINDOWS_CRTDBG
-#include <crtdbg.h>
-
-namespace Catch {
-
-    LeakDetector::LeakDetector() {
-        int flag = _CrtSetDbgFlag(_CRTDBG_REPORT_FLAG);
-        flag |= _CRTDBG_LEAK_CHECK_DF;
-        flag |= _CRTDBG_ALLOC_MEM_DF;
-        _CrtSetDbgFlag(flag);
-        _CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_FILE | _CRTDBG_MODE_DEBUG);
-        _CrtSetReportFile(_CRT_WARN, _CRTDBG_FILE_STDERR);
-        // Change this to leaking allocation's number to break there
-        _CrtSetBreakAlloc(-1);
-    }
-}
-
-#else // ^^ Windows crt debug heap enabled // Windows crt debug heap disabled vv
-
-    Catch::LeakDetector::LeakDetector() {}
-
-#endif // CATCH_CONFIG_WINDOWS_CRTDBG
-
-Catch::LeakDetector::~LeakDetector() {
-    Catch::cleanUp();
-}
-
-
-/////////////////////////////////////////////
-// vvv formerly catch_message_info.cpp vvv //
-/////////////////////////////////////////////
-
-#include <catch2/internal/catch_message_info.hpp>
-
-namespace Catch {
-
-    MessageInfo::MessageInfo(   StringRef _macroName,
-                                SourceLineInfo const& _lineInfo,
-                                ResultWas::OfType _type )
-    :   macroName( _macroName ),
-        lineInfo( _lineInfo ),
-        type( _type ),
-        sequence( ++globalCount )
-    {}
-
-    // This may need protecting if threading support is added
-    unsigned int MessageInfo::globalCount = 0;
-
-} // end namespace Catch
-
-
-
-
-//////////////////////////////////////////
-// vvv formerly catch_lazy_expr.cpp vvv //
-//////////////////////////////////////////
-#include <catch2/internal/catch_lazy_expr.hpp>
-#include <catch2/internal/catch_decomposer.hpp>
-
-namespace Catch {
-
-    auto operator << (std::ostream& os, LazyExpression const& lazyExpr) -> std::ostream& {
-        if (lazyExpr.m_isNegated)
-            os << '!';
-
-        if (lazyExpr) {
-            if (lazyExpr.m_isNegated && lazyExpr.m_transientExpression->isBinaryExpression())
-                os << '(' << *lazyExpr.m_transientExpression << ')';
-            else
-                os << *lazyExpr.m_transientExpression;
-        } else {
-            os << "{** error - unchecked empty expression requested **}";
-        }
-        return os;
-    }
-
-} // namespace Catch
diff --git a/src/catch2/internal/catch_decomposer.cpp b/src/catch2/internal/catch_decomposer.cpp
new file mode 100644
index 00000000..a8569538
--- /dev/null
+++ b/src/catch2/internal/catch_decomposer.cpp
@@ -0,0 +1,23 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/internal/catch_decomposer.hpp>
+
+namespace Catch {
+
+    ITransientExpression::~ITransientExpression() = default;
+
+    void formatReconstructedExpression( std::ostream &os, std::string const& lhs, StringRef op, std::string const& rhs ) {
+        if( lhs.size() + rhs.size() < 40 &&
+                lhs.find('\n') == std::string::npos &&
+                rhs.find('\n') == std::string::npos )
+            os << lhs << ' ' << op << ' ' << rhs;
+        else
+            os << lhs << '\n' << op << '\n' << rhs;
+    }
+}
diff --git a/src/catch2/internal/catch_errno_guard.cpp b/src/catch2/internal/catch_errno_guard.cpp
new file mode 100644
index 00000000..95c192df
--- /dev/null
+++ b/src/catch2/internal/catch_errno_guard.cpp
@@ -0,0 +1,16 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/internal/catch_errno_guard.hpp>
+
+#include <cerrno>
+
+namespace Catch {
+        ErrnoGuard::ErrnoGuard():m_oldErrno(errno){}
+        ErrnoGuard::~ErrnoGuard() { errno = m_oldErrno; }
+}
diff --git a/src/catch2/internal/catch_lazy_expr.cpp b/src/catch2/internal/catch_lazy_expr.cpp
new file mode 100644
index 00000000..96ecf5c3
--- /dev/null
+++ b/src/catch2/internal/catch_lazy_expr.cpp
@@ -0,0 +1,29 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/internal/catch_lazy_expr.hpp>
+#include <catch2/internal/catch_decomposer.hpp>
+
+namespace Catch {
+
+    auto operator << (std::ostream& os, LazyExpression const& lazyExpr) -> std::ostream& {
+        if (lazyExpr.m_isNegated)
+            os << '!';
+
+        if (lazyExpr) {
+            if (lazyExpr.m_isNegated && lazyExpr.m_transientExpression->isBinaryExpression())
+                os << '(' << *lazyExpr.m_transientExpression << ')';
+            else
+                os << *lazyExpr.m_transientExpression;
+        } else {
+            os << "{** error - unchecked empty expression requested **}";
+        }
+        return os;
+    }
+
+} // namespace Catch
diff --git a/src/catch2/internal/catch_leak_detector.cpp b/src/catch2/internal/catch_leak_detector.cpp
new file mode 100644
index 00000000..c9abbdfc
--- /dev/null
+++ b/src/catch2/internal/catch_leak_detector.cpp
@@ -0,0 +1,38 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/internal/catch_leak_detector.hpp>
+#include <catch2/interfaces/catch_interfaces_registry_hub.hpp>
+#include <catch2/catch_user_config.hpp>
+
+#ifdef CATCH_CONFIG_WINDOWS_CRTDBG
+#include <crtdbg.h>
+
+namespace Catch {
+
+    LeakDetector::LeakDetector() {
+        int flag = _CrtSetDbgFlag(_CRTDBG_REPORT_FLAG);
+        flag |= _CRTDBG_LEAK_CHECK_DF;
+        flag |= _CRTDBG_ALLOC_MEM_DF;
+        _CrtSetDbgFlag(flag);
+        _CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_FILE | _CRTDBG_MODE_DEBUG);
+        _CrtSetReportFile(_CRT_WARN, _CRTDBG_FILE_STDERR);
+        // Change this to leaking allocation's number to break there
+        _CrtSetBreakAlloc(-1);
+    }
+}
+
+#else // ^^ Windows crt debug heap enabled // Windows crt debug heap disabled vv
+
+    Catch::LeakDetector::LeakDetector() {}
+
+#endif // CATCH_CONFIG_WINDOWS_CRTDBG
+
+Catch::LeakDetector::~LeakDetector() {
+    Catch::cleanUp();
+}
diff --git a/src/catch2/internal/catch_message_info.cpp b/src/catch2/internal/catch_message_info.cpp
new file mode 100644
index 00000000..11127e3f
--- /dev/null
+++ b/src/catch2/internal/catch_message_info.cpp
@@ -0,0 +1,25 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/internal/catch_message_info.hpp>
+
+namespace Catch {
+
+    MessageInfo::MessageInfo(   StringRef _macroName,
+                                SourceLineInfo const& _lineInfo,
+                                ResultWas::OfType _type )
+    :   macroName( _macroName ),
+        lineInfo( _lineInfo ),
+        type( _type ),
+        sequence( ++globalCount )
+    {}
+
+    // This may need protecting if threading support is added
+    unsigned int MessageInfo::globalCount = 0;
+
+} // end namespace Catch
diff --git a/src/catch2/internal/catch_polyfills.cpp b/src/catch2/internal/catch_polyfills.cpp
new file mode 100644
index 00000000..13e60f4a
--- /dev/null
+++ b/src/catch2/internal/catch_polyfills.cpp
@@ -0,0 +1,34 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/internal/catch_polyfills.hpp>
+#include <catch2/internal/catch_compiler_capabilities.hpp>
+#include <catch2/catch_user_config.hpp>
+
+#include <cmath>
+
+namespace Catch {
+
+#if !defined(CATCH_CONFIG_POLYFILL_ISNAN)
+    bool isnan(float f) {
+        return std::isnan(f);
+    }
+    bool isnan(double d) {
+        return std::isnan(d);
+    }
+#else
+    // For now we only use this for embarcadero
+    bool isnan(float f) {
+        return std::_isnan(f);
+    }
+    bool isnan(double d) {
+        return std::_isnan(d);
+    }
+#endif
+
+} // end namespace Catch
diff --git a/src/catch2/internal/catch_startup_exception_registry.cpp b/src/catch2/internal/catch_startup_exception_registry.cpp
new file mode 100644
index 00000000..7681f442
--- /dev/null
+++ b/src/catch2/internal/catch_startup_exception_registry.cpp
@@ -0,0 +1,29 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/internal/catch_startup_exception_registry.hpp>
+#include <catch2/internal/catch_compiler_capabilities.hpp>
+#include <catch2/catch_user_config.hpp>
+
+namespace Catch {
+#if !defined(CATCH_CONFIG_DISABLE_EXCEPTIONS)
+    void StartupExceptionRegistry::add( std::exception_ptr const& exception ) noexcept {
+        CATCH_TRY {
+            m_exceptions.push_back(exception);
+        } CATCH_CATCH_ALL {
+            // If we run out of memory during start-up there's really not a lot more we can do about it
+            std::terminate();
+        }
+    }
+
+    std::vector<std::exception_ptr> const& StartupExceptionRegistry::getExceptions() const noexcept {
+        return m_exceptions;
+    }
+#endif
+
+} // end namespace Catch
diff --git a/src/catch2/internal/catch_uncaught_exceptions.cpp b/src/catch2/internal/catch_uncaught_exceptions.cpp
new file mode 100644
index 00000000..c6251a3f
--- /dev/null
+++ b/src/catch2/internal/catch_uncaught_exceptions.cpp
@@ -0,0 +1,26 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/internal/catch_uncaught_exceptions.hpp>
+#include <catch2/internal/catch_compiler_capabilities.hpp>
+#include <catch2/internal/catch_config_uncaught_exceptions.hpp>
+#include <catch2/catch_user_config.hpp>
+
+#include <exception>
+
+namespace Catch {
+    bool uncaught_exceptions() {
+#if defined(CATCH_CONFIG_DISABLE_EXCEPTIONS)
+        return false;
+#elif defined(CATCH_CONFIG_CPP17_UNCAUGHT_EXCEPTIONS)
+        return std::uncaught_exceptions() > 0;
+#else
+        return std::uncaught_exception();
+#endif
+  }
+} // end namespace Catch