[LLVM-COV] Replace tabs to 2-space indentation in the HTML coverage report.

[MaggieYi]

Summary

When using llvm-cov.exe to generate the HTML report, the HTML report can look quite different to the source file if it includes tabs. The patch includes:

1. Use the default tab size is 2 spaces instead of 8 spaces.
2. Add a command line switch (-tab-size) that allows user to set the tab size.

[vsk]

Mostly looks good. The logic in escape() looks correct.

test/tools/llvm-cov/showTabsHTML.cpp

4

Does the second RUN line achieve any additional test coverage for this patch? If not, please remove it.

17

Ditto, please trim this set of CHECKs.

22

Since this test is just checking whether tabs are expanded properly, please keep the CHECKs on lines {9, 14, 18} and remove the rest. That should make the test easier to maintain.

tools/llvm-cov/CoverageViewOptions.h

37

Please don't introduce static members -- it should be possible to pass a CoverageViewOptions instance instead.

tools/llvm-cov/SourceCoverageViewHTML.cpp

45

Capitalize the iterator variable name.

[MaggieYi]

Thanks Vedant, I have updated the patch following your comments.

[MaggieYi]

Following Vedant's comments, all issues have been fixed.

[vsk]

Great! LGTM.

test/tools/llvm-cov/Inputs/showTabsHTML.proftext

+main
+# Func Hash:
+0
+# Num Counters:
+1
+# Counter Values:
+1
+

test/tools/llvm-cov/showTabsHTML.cpp

+// RUN: llvm-profdata merge -o %t.profdata %S/Inputs/showTabsHTML.proftext
+// RUN: llvm-cov show %S/Inputs/showTabsHTML.covmapping -format html -instr-profile %t.profdata -filename-equivalence %s | FileCheck -check-prefix=CHECK %s
+
+int main(int argc, char ** argv) {
+  (void) "This tab starts at column 0";            // CHECK:   (void) "This tab starts at column 0";
+  (void) "  This tab starts at column 10";           // CHECK: (void) "  This tab starts at column 10";
+  (void) "This    tab starts at column 15";           // CHECK: (void) "This   tab starts at column 15";
+
+  return 0;
+}
+
+// RUN: llvm-cov show %S/Inputs/showTabsHTML.covmapping -format html -tab-size=3 -instr-profile %t.profdata -filename-equivalence %s | FileCheck -check-prefix=CHECK-TABSIZE %s
+
+// CHECK-TABSIZE:    (void) "This tab starts at column 0";
+// CHECK-TABSIZE: (void) "  This tab starts at column 10";
+// CHECK-TABSIZE: (void) "This     tab starts at column 15";
 No newline at end of file

tools/llvm-cov/CodeCoverage.cpp

cl::opt<bool> ShowInstantiations("show-instantiations", cl::Optional,
                                    cl::cat(ViewCategory));
 
   cl::opt<std::string> ShowOutputDirectory(
       "output-dir", cl::init(""),
       cl::desc("Directory in which coverage information is written out"));
   cl::alias ShowOutputDirectoryA("o", cl::desc("Alias for --output-dir"),
                                  cl::aliasopt(ShowOutputDirectory));
 
+  cl::opt<uint32_t> TabSize(
+      "tab-size", cl::Hidden, cl::init(2),
+      cl::desc("Set tab size for the HTML coverage report (default = 2)"));
+
   auto Err = commandLineParser(argc, argv);
   if (Err)
     return Err;
 
   ViewOpts.ShowLineNumbers = true;
   ViewOpts.ShowLineStats = ShowLineExecutionCounts.getNumOccurrences() != 0 ||
                            !ShowRegions || ShowBestLineRegionsCounts;
   ViewOpts.ShowRegionMarkers = ShowRegions || ShowBestLineRegionsCounts;
   ViewOpts.ShowLineStatsOrRegionMarkers = ShowBestLineRegionsCounts;
   ViewOpts.ShowExpandedRegions = ShowExpansions;
   ViewOpts.ShowFunctionInstantiations = ShowInstantiations;
   ViewOpts.ShowOutputDirectory = ShowOutputDirectory;
+  ViewOpts.TabSize = TabSize;
 
   if (ViewOpts.hasOutputDirectory()) {
     if (auto E = sys::fs::create_directories(ViewOpts.ShowOutputDirectory)) {
       error("Could not create output directory!", E.message());
       return 1;
     }
   }
 

tools/llvm-cov/CoverageViewOptions.h

struct CoverageViewOptions {
   bool ShowRegionMarkers;
   bool ShowLineStatsOrRegionMarkers;
   bool ShowExpandedRegions;
   bool ShowFunctionInstantiations;
   bool ShowFullFilenames;
   OutputFormat Format;
   std::string ShowOutputDirectory;
   std::vector<std::string> DemanglerOpts;
+  uint32_t TabSize;
 
   /// \brief Change the output's stream color if the colors are enabled.
   ColoredRawOstream colored_ostream(raw_ostream &OS,
                                     raw_ostream::Colors Color) const {
     return llvm::colored_ostream(OS, Color, Colors);
   }
 
   /// \brief Check if an output directory has been specified.
   bool hasOutputDirectory() const { return !ShowOutputDirectory.empty(); }
 
   /// \brief Check if a demangler has been specified.
   bool hasDemangler() const { return !DemanglerOpts.empty(); }
 };
 }
 
 #endif // LLVM_COV_COVERAGEVIEWOPTIONS_H

tools/llvm-cov/SourceCoverageViewHTML.cpp

 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/Path.h"
 
 using namespace llvm;
 
 namespace {
 
 // Return a string with the special characters in \p Str escaped.
-std::string escape(StringRef Str) {
+std::string escape(StringRef Str, const CoverageViewOptions &Opts) {
   std::string Result;
+  unsigned ColNum = 0; // Record the column number.
   for (char C : Str) {
+    ++ColNum;
     if (C == '&')
       Result += "&";
     else if (C == '<')
       Result += "&lt;";
     else if (C == '>')
       Result += "&gt;";
     else if (C == '\"')
       Result += "&quot;";
-    else
+    else if (C == '\n' || C == '\r') {
+      Result += C;
+      ColNum = 0;
+    } else if (C == '\t') {
+      // Replace '\t' with TabSize spaces.
+      unsigned NumSpaces = Opts.TabSize - (--ColNum % Opts.TabSize);
+      for (unsigned I = 0; I < NumSpaces; ++I)
+        Result += "&nbsp;";
+      ColNum += NumSpaces;
+    } else
       Result += C;
   }
   return Result;
 }
 
 // Create a \p Name tag around \p Str, and optionally set its \p ClassName.
 std::string tag(const std::string &Name, const std::string &Str,
                 const std::string &ClassName = "") {
std::string getPathToStyle(StringRef ViewPath) {
   std::string PathToStyle = "";
   std::string PathSep = sys::path::get_separator();
   unsigned NumSeps = ViewPath.count(PathSep);
   for (unsigned I = 0, E = NumSeps; I < E; ++I)
     PathToStyle += ".." + PathSep;
   return PathToStyle + "style.css";
 }
 
-void emitPrelude(raw_ostream &OS, const std::string &PathToStyle = "") {
+void emitPrelude(raw_ostream &OS, const CoverageViewOptions &Opts,
+                 const std::string &PathToStyle = "") {
   OS << "<!doctype html>"
         "<html>"
      << BeginHeader;
 
   // Link to a stylesheet if one is available. Otherwise, use the default style.
   if (PathToStyle.empty())
     OS << "<style>" << CSSForCoverage << "</style>";
   else
-    OS << "<link rel='stylesheet' type='text/css' href='" << escape(PathToStyle)
-       << "'>";
+    OS << "<link rel='stylesheet' type='text/css' href='"
+       << escape(PathToStyle, Opts) << "'>";
 
   OS << EndHeader << "<body>" << BeginCenteredDiv;
 }
 
 void emitEpilog(raw_ostream &OS) {
   OS << EndCenteredDiv << "</body>"
                           "</html>";
 }
 
 } // anonymous namespace
 
 Expected<CoveragePrinter::OwnedStream>
 CoveragePrinterHTML::createViewFile(StringRef Path, bool InToplevel) {
   auto OSOrErr = createOutputStream(Path, "html", InToplevel);
   if (!OSOrErr)
     return OSOrErr;
 
   OwnedStream OS = std::move(OSOrErr.get());
 
   if (!Opts.hasOutputDirectory()) {
-    emitPrelude(*OS.get());
+    emitPrelude(*OS.get(), Opts);
   } else {
     std::string ViewPath = getOutputPath(Path, "html", InToplevel);
-    emitPrelude(*OS.get(), getPathToStyle(ViewPath));
+    emitPrelude(*OS.get(), Opts, getPathToStyle(ViewPath));
   }
 
   return std::move(OS);
 }
 
 void CoveragePrinterHTML::closeViewFile(OwnedStream OS) {
   emitEpilog(*OS.get());
 }
 
 Error CoveragePrinterHTML::createIndexFile(ArrayRef<StringRef> SourceFiles) {
   auto OSOrErr = createOutputStream("index", "html", /*InToplevel=*/true);
   if (Error E = OSOrErr.takeError())
     return E;
   auto OS = std::move(OSOrErr.get());
   raw_ostream &OSRef = *OS.get();
 
   // Emit a table containing links to reports for each file in the covmapping.
   assert(Opts.hasOutputDirectory() && "No output directory for index file");
-  emitPrelude(OSRef, getPathToStyle(""));
+  emitPrelude(OSRef, Opts, getPathToStyle(""));
   OSRef << BeginSourceNameDiv << "Index" << EndSourceNameDiv;
   OSRef << BeginTable;
   for (StringRef SF : SourceFiles) {
-    std::string LinkText = escape(sys::path::relative_path(SF));
+    std::string LinkText = escape(sys::path::relative_path(SF), Opts);
     std::string LinkTarget =
-        escape(getOutputPath(SF, "html", /*InToplevel=*/false));
+        escape(getOutputPath(SF, "html", /*InToplevel=*/false), Opts);
     OSRef << tag("tr", tag("td", tag("pre", a(LinkTarget, LinkText), "code")));
   }
   OSRef << EndTable;
   emitEpilog(OSRef);
 
   // Emit the default stylesheet.
   auto CSSOrErr = createOutputStream("style", "css", /*InToplevel=*/true);
   if (Error E = CSSOrErr.takeError())
void SourceCoverageViewHTML::renderViewHeader(raw_ostream &OS) {
   OS << BeginTable;
 }
 
 void SourceCoverageViewHTML::renderViewFooter(raw_ostream &OS) {
   OS << EndTable;
 }
 
 void SourceCoverageViewHTML::renderSourceName(raw_ostream &OS) {
-  OS << BeginSourceNameDiv << tag("pre", escape(getSourceName()))
+  OS << BeginSourceNameDiv << tag("pre", escape(getSourceName(), getOptions()))
      << EndSourceNameDiv;
 }
 
 void SourceCoverageViewHTML::renderLinePrefix(raw_ostream &OS, unsigned) {
   OS << "<tr>";
 }
 
 void SourceCoverageViewHTML::renderLineSuffix(raw_ostream &OS, unsigned) {
void SourceCoverageViewHTML::renderLine(
 
   // |Line| + 1 is needed to avoid underflow when, e.g |Line| = 0 and LCol = 1.
   Snip(LCol - 1, Line.size() + 1 - LCol);
   assert(LCol == Line.size() + 1 && "Final snippet doesn't reach the EOL");
 
   // 2. Escape all of the snippets.
 
   for (unsigned I = 0, E = Snippets.size(); I < E; ++I)
-    Snippets[I] = escape(Snippets[I]);
+    Snippets[I] = escape(Snippets[I], getOptions());
 
   // 3. Use \p WrappedSegment to set the highlight for snippet 0. Use segment
   //    1 to set the highlight for snippet 2, segment 2 to set the highlight for
   //    snippet 3, and so on.
 
   Optional<std::string> Color;
   SmallVector<std::pair<unsigned, unsigned>, 4> HighlightedRanges;
   auto Highlight = [&](const std::string &Snippet, unsigned LC, unsigned RC) {