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- Removed unnecessary mention of Edit
- Removed fallback logic when the absolute path isn't found
- Extracted mapInputsToAbsPaths as a separate function

Author: bc-lee

clang-tools-extra/include-cleaner/tool/IncludeCleaner.cpp

@@ -282,6 +282,48 @@ std::function<bool(llvm::StringRef)> headerFilter() {
   };
 }
 
+// Maps absolute path of each files of each compilation commands to the
+// absolute path of the input file.
+llvm::Expected<std::map<std::string, std::string>>
+mapInputsToAbsPaths(clang::tooling::CompilationDatabase &CDB,
+                    llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS,
+                    const std::vector<std::string> &Inputs) {
+  std::map<std::string, std::string> CDBToAbsPaths;
+  // Factory.editedFiles()` will contain the final code, along with the
+  // path given in the compilation database. That path can be
+  // absolute or relative, and if it is relative, it is relative to the
+  // "Directory" field in the compilation database. We need to make it
+  // absolute to write the final code to the correct path.
+  for (auto &Source : Inputs) {
+    llvm::SmallString<256> AbsPath(Source);
+    if (auto Err = VFS->makeAbsolute(AbsPath)) {
+      llvm::errs() << "Failed to get absolute path for " << Source << " : "
+                   << Err.message() << '\n';
+      return std::move(llvm::errorCodeToError(Err));
+    }
+    std::vector<clang::tooling::CompileCommand> Cmds =
+        CDB.getCompileCommands(AbsPath);
+    if (Cmds.empty()) {
+      // It should be found in the compilation database, even user didn't
+      // specify the compilation database, the `FixedCompilationDatabase` will
+      // create an entry from the arguments. So it is an error if we can't
+      // find the compile commands.
+      std::string ErrorMsg =
+          llvm::formatv("No compile commands found for {0}", AbsPath).str();
+      llvm::errs() << ErrorMsg << '\n';
+      return llvm::make_error<llvm::StringError>(
+          ErrorMsg, llvm::inconvertibleErrorCode());
+    }
+    for (const auto &Cmd : Cmds) {
+      llvm::SmallString<256> CDBPath(Cmd.Filename);
+      std::string Directory(Cmd.Directory);
+      llvm::sys::fs::make_absolute(Cmd.Directory, CDBPath);
+      CDBToAbsPaths[std::string(CDBPath)] = std::string(AbsPath);
+    }
+  }
+  return CDBToAbsPaths;
+}
+
 } // namespace
 } // namespace include_cleaner
 } // namespace clang
@@ -311,40 +353,10 @@ int main(int argc, const char **argv) {
   auto &CDB = OptionsParser->getCompilations();
   // CDBToAbsPaths is a map from the path in the compilation database to the
   // writable absolute path of the file.
-  std::map<std::string, std::string> CDBToAbsPaths;
-  // if Edit is enabled, `Factory.editedFiles()` will contain the final code,
-  // along with the path given in the compilation database. That path can be
-  // absolute or relative, and if it is relative, it is relative to the
-  // "Directory" field in the compilation database. We need to make it
-  // absolute to write the final code to the correct path.
-  for (auto &Source : OptionsParser->getSourcePathList()) {
-    llvm::SmallString<256> AbsPath(Source);
-    if (auto Err = VFS->makeAbsolute(AbsPath)) {
-      llvm::errs() << "Failed to get absolute path for " << Source << " : "
-                   << Err.message() << '\n';
-      return 1;
-    }
-    std::vector<clang::tooling::CompileCommand> Cmds =
-        CDB.getCompileCommands(AbsPath);
-    if (Cmds.empty()) {
-      // Try with the original path.
-      Cmds = CDB.getCompileCommands(Source);
-      if (Cmds.empty()) {
-        // It should be found in the compilation database, even user didn't
-        // specify the compilation database, the `FixedCompilationDatabase` will
-        // create an entry from the arguments. So it is an error if we can't
-        // find the compile commands.
-        llvm::errs() << "No compile commands found for " << Source << '\n';
-        return 1;
-      }
-    }
-    for (const auto &Cmd : Cmds) {
-      llvm::SmallString<256> CDBPath(Cmd.Filename);
-      std::string Directory(Cmd.Directory);
-      llvm::sys::fs::make_absolute(Cmd.Directory, CDBPath);
-      CDBToAbsPaths[std::string(CDBPath)] = std::string(AbsPath);
-    }
-  }
+  auto CDBToAbsPaths =
+      mapInputsToAbsPaths(CDB, VFS, OptionsParser->getSourcePathList());
+  if (!CDBToAbsPaths)
+    return 1;
 
   clang::tooling::ClangTool Tool(CDB, OptionsParser->getSourcePathList());
 
@@ -356,8 +368,8 @@ int main(int argc, const char **argv) {
   if (Edit) {
     for (const auto &NameAndContent : Factory.editedFiles()) {
       llvm::StringRef FileName = NameAndContent.first();
-      if (auto It = CDBToAbsPaths.find(FileName.str());
-          It != CDBToAbsPaths.end())
+      if (auto It = CDBToAbsPaths->find(FileName.str());
+          It != CDBToAbsPaths->end())
         FileName = It->second;
 
       const std::string &FinalCode = NameAndContent.second;