clang-format: Make GetStyle return Expected<FormatStyle> instead of FormatStyle

Change the contract of GetStyle so that it returns an error when an error occurs
(i.e. when it writes to stderr), and only returns the fallback style when it
can't find a configuration file.

Differential Revision: https://reviews.llvm.org/D28081

llvm-svn: 292174

1 files changed, 17 insertions, 7 deletions

diff --git a/clang/tools/clang-format/ClangFormat.cpp b/clang/tools/clang-format/ClangFormat.cpp
index 6c50daf5383..b08d4fa4c18 100644
--- a/clang/tools/clang-format/ClangFormat.cpp
+++ b/clang/tools/clang-format/ClangFormat.cpp
@@ -249,12 +249,17 @@ static bool format(StringRef FileName) {
   if (fillRanges(Code.get(), Ranges))
     return true;
   StringRef AssumedFileName = (FileName == "-") ? AssumeFileName : FileName;
-  FormatStyle FormatStyle =
+
+  llvm::Expected<FormatStyle> FormatStyle =
       getStyle(Style, AssumedFileName, FallbackStyle, Code->getBuffer());
+  if (!FormatStyle) {
+    llvm::errs() << llvm::toString(FormatStyle.takeError()) << "\n";
+    return true;
+  }
   if (SortIncludes.getNumOccurrences() != 0)
-    FormatStyle.SortIncludes = SortIncludes;
+    FormatStyle->SortIncludes = SortIncludes;
   unsigned CursorPosition = Cursor;
-  Replacements Replaces = sortIncludes(FormatStyle, Code->getBuffer(), Ranges,
+  Replacements Replaces = sortIncludes(*FormatStyle, Code->getBuffer(), Ranges,
                                        AssumedFileName, &CursorPosition);
   auto ChangedCode = tooling::applyAllReplacements(Code->getBuffer(), Replaces);
   if (!ChangedCode) {
@@ -264,7 +269,7 @@ static bool format(StringRef FileName) {
   // Get new affected ranges after sorting `#includes`.
   Ranges = tooling::calculateRangesAfterReplacements(Replaces, Ranges);
   bool IncompleteFormat = false;
-  Replacements FormatChanges = reformat(FormatStyle, *ChangedCode, Ranges,
+  Replacements FormatChanges = reformat(*FormatStyle, *ChangedCode, Ranges,
                                         AssumedFileName, &IncompleteFormat);
   Replaces = Replaces.merge(FormatChanges);
   if (OutputXML) {
@@ -334,10 +339,15 @@ int main(int argc, const char **argv) {
     cl::PrintHelpMessage();
 
   if (DumpConfig) {
-    std::string Config =
-        clang::format::configurationAsText(clang::format::getStyle(
+    llvm::Expected<clang::format::FormatStyle> FormatStyle =
+        clang::format::getStyle(
             Style, FileNames.empty() ? AssumeFileName : FileNames[0],
-            FallbackStyle));
+            FallbackStyle);
+    if (!FormatStyle) {
+      llvm::errs() << llvm::toString(FormatStyle.takeError()) << "\n";
+      return 1;
+    }
+    std::string Config = clang::format::configurationAsText(*FormatStyle);
     outs() << Config << "\n";
     return 0;
   }