[llvm-cov] Improvements for summary report generated in HTML format.

Summary:
This commit adds the following changes:

1) coverage numbers are aligned to the left and padded with spaces in order to
provide better readability for percentage values, e.g.:

```
file1     |  89.13% (123 / 2323)    | 100.00% (55 / 55)    |   9.33% (14545 / 234234)
file_asda |   1.78% ( 23 / 4323)    |  32.31% (555 / 6555) |  67.89% (1545 / 2234)
fileXXX   | 100.00% (12323 / 12323) | 100.00% (555 / 555)  | 100.00% (12345 / 12345)
```

2) added "hover" attribute to CSS for highlighting table row under mouse cursor
see screenshot attached to the phabricator review page

{F5764813}

3) table title row and "totals" row now use bold text

Reviewers: vsk, morehouse

Reviewed By: vsk

Subscribers: kcc, llvm-commits

Differential Revision: https://reviews.llvm.org/D42093

llvm-svn: 323892

1 files changed, 37 insertions, 14 deletions

diff --git a/llvm/tools/llvm-cov/SourceCoverageViewHTML.cpp b/llvm/tools/llvm-cov/SourceCoverageViewHTML.cpp
index e45c6f4..f7826e4 100644
--- a/llvm/tools/llvm-cov/SourceCoverageViewHTML.cpp
+++ b/llvm/tools/llvm-cov/SourceCoverageViewHTML.cpp
@@ -116,24 +116,39 @@ table {
   background: #ffffff;
   border: 1px solid #dbdbdb;
 }
+.light-row-bold {
+  background: #ffffff;
+  border: 1px solid #dbdbdb;
+  font-weight: bold;
+}
 .column-entry {
-  text-align: right;
+  text-align: left;
 }
-.column-entry-left {
+.column-entry-bold {
+  font-weight: bold;
   text-align: left;
 }
 .column-entry-yellow {
-  text-align: right;
+  text-align: left;
   background-color: #ffffd0;
 }
+.column-entry-yellow:hover {
+  background-color: #fffff0;
+}
 .column-entry-red {
-  text-align: right;
+  text-align: left;
   background-color: #ffd0d0;
 }
+.column-entry-red:hover {
+  background-color: #fff0f0;
+}
 .column-entry-green {
-  text-align: right;
+  text-align: left;
   background-color: #d0ffd0;
 }
+.column-entry-green:hover {
+  background-color: #f0fff0;
+}
 .line-number {
   text-align: right;
   color: #aaa;
@@ -184,10 +199,11 @@ table {
 }
 th, td {
   vertical-align: top;
-  padding: 2px 5px;
+  padding: 2px 8px;
   border-collapse: collapse;
   border-right: solid 1px #eee;
   border-left: solid 1px #eee;
+  text-align: left;
 }
 td:first-child {
   border-left: none;
@@ -195,6 +211,9 @@ td:first-child {
 td:last-child {
   border-right: none;
 }
+tr:hover {
+  background-color: #f0f0f0;
+}
 )";
 
 const char *EndHeader = "</head>";
@@ -287,13 +306,14 @@ void CoveragePrinterHTML::closeViewFile(OwnedStream OS) {
 static void emitColumnLabelsForIndex(raw_ostream &OS,
                                      const CoverageViewOptions &Opts) {
   SmallVector<std::string, 4> Columns;
-  Columns.emplace_back(tag("td", "Filename", "column-entry-left"));
-  Columns.emplace_back(tag("td", "Function Coverage", "column-entry"));
+  Columns.emplace_back(tag("td", "Filename", "column-entry-bold"));
+  Columns.emplace_back(tag("td", "Function Coverage", "column-entry-bold"));
   if (Opts.ShowInstantiationSummary)
-    Columns.emplace_back(tag("td", "Instantiation Coverage", "column-entry"));
-  Columns.emplace_back(tag("td", "Line Coverage", "column-entry"));
+    Columns.emplace_back(
+        tag("td", "Instantiation Coverage", "column-entry-bold"));
+  Columns.emplace_back(tag("td", "Line Coverage", "column-entry-bold"));
   if (Opts.ShowRegionSummary)
-    Columns.emplace_back(tag("td", "Region Coverage", "column-entry"));
+    Columns.emplace_back(tag("td", "Region Coverage", "column-entry-bold"));
   OS << tag("tr", join(Columns.begin(), Columns.end(), ""));
 }
 
@@ -323,7 +343,7 @@ void CoveragePrinterHTML::emitFileSummary(raw_ostream &OS, StringRef SF,
     {
       raw_string_ostream RSO{S};
       if (Total)
-        RSO << format("%*.2f", 7, Pctg) << "% ";
+        RSO << format("%6.2f", 7, Pctg) << "% ";
       else
         RSO << "- ";
       RSO << '(' << Hit << '/' << Total << ')';
@@ -339,7 +359,7 @@ void CoveragePrinterHTML::emitFileSummary(raw_ostream &OS, StringRef SF,
   // Simplify the display file path, and wrap it in a link if requested.
   std::string Filename;
   if (IsTotals) {
-    Filename = "TOTALS";
+    Filename = SF;
   } else {
     Filename = buildLinkToFile(SF, FCS);
   }
@@ -360,7 +380,10 @@ void CoveragePrinterHTML::emitFileSummary(raw_ostream &OS, StringRef SF,
                               FCS.RegionCoverage.getNumRegions(),
                               FCS.RegionCoverage.getPercentCovered());
 
-  OS << tag("tr", join(Columns.begin(), Columns.end(), ""), "light-row");
+  if (IsTotals)
+    OS << tag("tr", join(Columns.begin(), Columns.end(), ""), "light-row-bold");
+  else
+    OS << tag("tr", join(Columns.begin(), Columns.end(), ""), "light-row");
 }
 
 Error CoveragePrinterHTML::createIndexFile(