Truncate serialized dia files instead of non-specific error.

Author: davidungar

include/swift/AST/DiagnosticConsumer.h

@@ -100,7 +100,16 @@ class DiagnosticConsumer {
                                 const DiagnosticInfo &Info) = 0;
 
   /// \returns true if an error occurred while finishing-up.
-  virtual bool finishProcessing(SourceManager &) { return false; }
+  virtual bool finishProcessing(SourceManager &SM) { return false; }
+
+  /// In batch mode, any error causes failure for all primary files, but
+  /// anyone consulting .dia files will only see an error for a particular
+  /// primary in that primary's serialized diagnostics file. For other
+  /// primaries' serialized diagnostics files, do something to signal the driver
+  /// what happened. This is only meaningful for SerializedDiagnosticConsumers,
+  /// so here's a placeholder.
+
+  virtual void informDriverOfIncompleteBatchModeCompilation() {}
 };
 
 /// \brief DiagnosticConsumer that discards all diagnostics.
@@ -198,8 +207,9 @@ class FileSpecificDiagnosticConsumer : public DiagnosticConsumer {
 private:
   /// In batch mode, any error causes failure for all primary files, but
   /// Xcode will only see an error for a particular primary in that primary's
-  /// serialized diagnostics file. So, emit errors for all other primaries here.
-  void addNonSpecificErrors(SourceManager &SM);
+  /// serialized diagnostics file. So, tell the subconsumers to inform the
+  /// driver of incomplete batch mode compilation.
+  void tellSubconsumersToInformDriverOfIncompleteBatchModeCompilation() const;
 
   void computeConsumersOrderedByRange(SourceManager &SM);
 

include/swift/AST/DiagnosticsFrontend.def

@@ -235,8 +235,6 @@ WARNING(cannot_assign_value_to_conditional_compilation_flag,none,
 ERROR(error_optimization_remark_pattern, none, "%0 in '%1'",
       (StringRef, StringRef))
 
-ERROR(error_compilation_stopped_by_errors_in_other_files,none, "compilation stopped by errors in other files", ())
-
 #ifndef DIAG_NO_UNDEF
 # if defined(DIAG)
 #  undef DIAG

lib/AST/DiagnosticConsumer.cpp

@@ -190,7 +190,7 @@ void FileSpecificDiagnosticConsumer::handleDiagnostic(
 }
 
 bool FileSpecificDiagnosticConsumer::finishProcessing(SourceManager &SM) {
-  addNonSpecificErrors(SM);
+  tellSubconsumersToInformDriverOfIncompleteBatchModeCompilation();
 
   // Deliberately don't use std::any_of here because we don't want early-exit
   // behavior.
@@ -201,29 +201,13 @@ bool FileSpecificDiagnosticConsumer::finishProcessing(SourceManager &SM) {
   return hadError;
 }
 
-static void produceNonSpecificError(
-    FileSpecificDiagnosticConsumer::ConsumerSpecificInformation &consumerInfo,
-    SourceManager &SM) {
-  Diagnostic diagnostic(
-      diag::error_compilation_stopped_by_errors_in_other_files);
-
-  // Stolen from DiagnosticEngine::emitDiagnostic
-  DiagnosticInfo Info;
-  Info.ID = diagnostic.getID();
-
-  consumerInfo.consumer->handleDiagnostic(
-      SM, consumerInfo.range.getStart(), DiagnosticKind::Error,
-      DiagnosticEngine::diagnosticStringFor(diagnostic.getID()), {}, Info);
-}
-
-void FileSpecificDiagnosticConsumer::addNonSpecificErrors(SourceManager &SM) {
+void FileSpecificDiagnosticConsumer::
+    tellSubconsumersToInformDriverOfIncompleteBatchModeCompilation() const {
   if (!HasAnErrorBeenConsumed)
     return;
   for (auto &info : ConsumersOrderedByRange) {
-    if (!info.hasAnErrorBeenEmitted && info.consumer) {
-      produceNonSpecificError(info, SM);
-      info.hasAnErrorBeenEmitted = true;
-    }
+    if (!info.hasAnErrorBeenEmitted && info.consumer)
+      info.consumer->informDriverOfIncompleteBatchModeCompilation();
   }
 }
 

lib/Frontend/SerializedDiagnosticConsumer.cpp

@@ -130,6 +130,8 @@ class SerializedDiagnosticConsumer : public DiagnosticConsumer {
   /// \brief State shared among the various clones of this diagnostic consumer.
   llvm::IntrusiveRefCntPtr<SharedState> State;
   bool CalledFinishProcessing = false;
+  bool CompilationWasComplete = true;
+
 public:
   SerializedDiagnosticConsumer(StringRef serializedDiagnosticsPath)
       : State(new SharedState(serializedDiagnosticsPath)) {
@@ -168,11 +170,26 @@ class SerializedDiagnosticConsumer : public DiagnosticConsumer {
       return true;
     }
 
-    OS->write((char *)&State->Buffer.front(), State->Buffer.size());
-    OS->flush();
+    if (CompilationWasComplete) {
+      OS->write((char *)&State->Buffer.front(), State->Buffer.size());
+      OS->flush();
+    }
     return false;
   }
 
+  /// In batch mode, if any error occurs, no primaries can be compiled.
+  /// Some primaries will have errors in their diagnostics files and so
+  /// a client (such as Xcode) can see that those primaries failed.
+  /// Other primaries will have no errors in their diagnostics files.
+  /// In order for the driver to distinguish the two cases without parsing
+  /// the diagnostics, the frontend emits a truncated diagnostics file
+  /// for the latter case.
+  /// The unfortunate aspect is that the truncation discards warnings, etc.
+  
+  void informDriverOfIncompleteBatchModeCompilation() override {
+    CompilationWasComplete = false;
+  }
+
   void handleDiagnostic(SourceManager &SM, SourceLoc Loc,
                                 DiagnosticKind Kind,
                                 StringRef FormatString,

test/Misc/serialized-diagnostics-batch-mode-nonprimary-errors-only.swift

@@ -3,13 +3,9 @@
 // RUN: rm -f %t.*
 
 // RUN: not %target-swift-frontend -typecheck  -primary-file %s  -serialize-diagnostics-path %t.main.dia -primary-file %S/../Inputs/empty.swift  -serialize-diagnostics-path %t.empty.dia %S/Inputs/serialized-diagnostics-batch-mode-suppression-helper.swift  2> %t.stderr.txt
-// RUN: c-index-test -read-diagnostics %t.main.dia 2> %t.main.txt
-// RUN: c-index-test -read-diagnostics %t.empty.dia 2> %t.empty.txt
-
-// RUN: %FileCheck -check-prefix=GENERAL-ERROR-OCCURRED %s <%t.main.txt
-// RUN: %FileCheck -check-prefix=GENERAL-ERROR-OCCURRED %s <%t.empty.txt
-// GENERAL-ERROR-OCCURRED: compilation stopped by errors in other files
 
+// RUN: test -e %t.main.dia -a ! -s %t.empty.dia
+// RUN: test -e %t.empty.dia -a ! -s %t.empty.dia
 
 func test(x: SomeType) {
 }

test/Misc/serialized-diagnostics-batch-mode-nonprimary-errors.swift

@@ -4,10 +4,9 @@
 
 // RUN: not %target-swift-frontend -typecheck  -primary-file %s  -serialize-diagnostics-path %t.main.dia -primary-file %S/../Inputs/empty.swift  -serialize-diagnostics-path %t.empty.dia %S/Inputs/serialized-diagnostics-batch-mode-suppression-helper.swift  2> %t.stderr.txt
 // RUN: c-index-test -read-diagnostics %t.main.dia 2> %t.main.txt
-// RUN: c-index-test -read-diagnostics %t.empty.dia 2> %t.empty.txt
 
 // RUN: %FileCheck -check-prefix=NO-GENERAL-ERROR-OCCURRED %s <%t.main.txt
-// RUN: %FileCheck -check-prefix=GENERAL-ERROR-OCCURRED %s <%t.empty.txt
+// RUN: test -e %t.empty.dia -a ! -s %t.empty.dia
 // GENERAL-ERROR-OCCURRED: compilation stopped by errors in other files
 // NO-GENERAL-ERROR-OCCURRED-NOT: compilation stopped by errors in other files
 

test/Misc/serialized-diagnostics-batch-mode-primary-errors.swift

@@ -4,11 +4,10 @@
 
 // RUN: not %target-swift-frontend -typecheck  -primary-file %s  -serialize-diagnostics-path %t.main.dia -primary-file %S/../Inputs/empty.swift  -serialize-diagnostics-path %t.empty.dia  2> %t.stderr.txt
 // RUN: c-index-test -read-diagnostics %t.main.dia 2> %t.main.txt
-// RUN: c-index-test -read-diagnostics %t.empty.dia 2> %t.empty.txt
 
 // RUN: %FileCheck -check-prefix=ERROR %s <%t.main.txt
 // RUN: %FileCheck -check-prefix=NO-NONSPECIFIC-ERROR %s <%t.main.txt
-// RUN: %FileCheck -check-prefix=NONSPECIFIC-ERROR %s <%t.empty.txt
+// RUN: test -e %t.empty.dia -a ! -s %t.empty.dia
 
 // ERROR: error:
 // NONSPECIFIC-ERROR: error: compilation stopped by errors in other files
@@ -17,4 +16,3 @@
 func test(x: SomeType) {
   nonexistent()
 }
-