Strip comments from inlinable text when printing in swiftinterface files

lib/AST/InlinableText.cpp

@@ -189,41 +189,83 @@ struct ExtractInactiveRanges : public ASTWalker {
 };
 } // end anonymous namespace
 
+static void appendRange(
+  SourceManager &sourceMgr, SourceLoc start, SourceLoc end,
+  SmallVectorImpl<char> &scratch) {
+  unsigned bufferID = sourceMgr.findBufferContainingLoc(start);
+  unsigned offset = sourceMgr.getLocOffsetInBuffer(start, bufferID);
+  unsigned endOffset = sourceMgr.getLocOffsetInBuffer(end, bufferID);
+
+  // Strip comments from the chunk before adding it by re-lexing the range.
+  LangOptions FakeLangOpts;
+  Lexer lexer(FakeLangOpts, sourceMgr, bufferID, nullptr, LexerMode::Swift,
+    HashbangMode::Disallowed, CommentRetentionMode::ReturnAsTokens,
+    offset, endOffset);
+
+  SourceLoc nonCommentStart = start;
+  Token token;
+
+  // Re-lex the range, and skip the full text of `tok::comment` tokens.
+  while (!token.is(tok::eof)) {
+    lexer.lex(token);
+
+    if (token.is(tok::comment)) {
+      // Append the range from the last non-comment token to the beginning of this comment
+      // token.
+      SourceLoc commentLoc = token.getLoc();
+      auto charRange = CharSourceRange(sourceMgr, nonCommentStart, commentLoc);
+      StringRef text = sourceMgr.extractText(charRange);
+      scratch.append(text.begin(), text.end());
+
+      // Append a single whitespace character, to avoid fusing tokens.
+      scratch.push_back(' ');
+
+      // Set the start of the next non-comment range to the end of this token.
+      SourceLoc endLoc = Lexer::getLocForEndOfToken(sourceMgr, token.getLoc());
+
+      // The comment token's end location includes trailing whitespace, so trim trailing
+      // whitespace and only strip the portions of the comment that are not whitespace.
+      CharSourceRange range = CharSourceRange(sourceMgr, commentLoc, endLoc);
+      StringRef commentText = sourceMgr.extractText(range);
+      unsigned whitespaceOffset = commentText.size() - commentText.rtrim().size();
+      if (whitespaceOffset > 0) {
+        endLoc = endLoc.getAdvancedLoc(-whitespaceOffset);
+      }
+
+      nonCommentStart = endLoc;
+    }
+  }
+
+  if (nonCommentStart.isValid() && nonCommentStart != end) {
+    auto charRange = CharSourceRange(sourceMgr, nonCommentStart, end);
+    StringRef text = sourceMgr.extractText(charRange);
+    scratch.append(text.begin(), text.end());
+  }
+}
+
 StringRef swift::extractInlinableText(SourceManager &sourceMgr, ASTNode node,
                                       SmallVectorImpl<char> &scratch) {
   // Extract inactive ranges from the text of the node.
   ExtractInactiveRanges extractor(sourceMgr);
   node.walk(extractor);
 
-  // If there were no inactive ranges, then there were no #if configs.
-  // Return an unowned buffer directly into the source file.
-  if (extractor.ranges.empty()) {
-    auto range =
-      Lexer::getCharSourceRangeFromSourceRange(
-        sourceMgr, node.getSourceRange());
-    return sourceMgr.extractText(range);
-  }
-
   // Begin piecing together active code ranges.
 
   // Get the full start and end of the provided node, as character locations.
   SourceLoc start = node.getStartLoc();
   SourceLoc end = Lexer::getLocForEndOfToken(sourceMgr, node.getEndLoc());
   for (auto &range : extractor.getSortedRanges()) {
     // Add the text from the current 'start' to this ignored range's start.
-    auto charRange = CharSourceRange(sourceMgr, start, range.getStart());
-    auto chunk = sourceMgr.extractText(charRange);
-    scratch.append(chunk.begin(), chunk.end());
+    appendRange(sourceMgr, start, range.getStart(), scratch);
 
     // Set 'start' to the end of this range, effectively skipping it.
     start = range.getEnd();
   }
 
   // If there's leftover unignored text, add it.
   if (start != end) {
-    auto range = CharSourceRange(sourceMgr, start, end);
-    auto chunk = sourceMgr.extractText(range);
-    scratch.append(chunk.begin(), chunk.end());
+    appendRange(sourceMgr, start, end, scratch);
   }
+
   return { scratch.data(), scratch.size() };
 }

test/ModuleInterface/if-configs.swift

@@ -126,3 +126,33 @@ public func hasIfCompilerCheck(_ x: () -> Bool = {
 #endif
   }) {
 }
+
+// CHECK: func hasComments
+// CHECK: print(
+// CHECK-NOT: comment! don't mess up indentation!
+// CHECK: {{^}}    """
+// CHECK: {{^}}    """
+// CHECK-NOT: #if
+// CHECK-NOT: comment!
+// CHECK: return true
+public func hasComments() -> Bool {
+  /* comment! */ // comment!
+  #if NOT_PROVIDED
+    // comment!
+    return true
+  #endif
+
+  print(/* 
+    comment! 
+  */"this should show up")
+
+  print(
+    // comment! don't mess up indentation!
+    """
+    """)
+
+  #if !NOT_PROVIDED
+    // comment!
+    return/* comment! */true/* comment! */
+  #endif
+}