godoc search bug fixes:

- sort by package name (instead of package path) for results with snippets
- sort line numbers in results without snippets
- properly characterize package clauses
- experiment with a leaner look: no underlines for top-level godoc links in the left side bar

Still using colors to distinguish results. Next step.

R=rsc
http://go/go-review/1015016

doc/style.css

@@ -167,6 +167,11 @@ span.highlight {
 /* ------------------------------------------------------------------------- */
 /* Styles used by infoClassFmt */
 
+a.package {
+  text-decoration: none;
+  background-color: #FFFFFF;
+}
+
 a.import {
   text-decoration: none;
   background-color: #D8D8D8;

lib/godoc/godoc.html

@@ -25,26 +25,26 @@
 
 <div id="linkList">
   <ul>
-    <li class="navhead"><a href="/">Home</a></li>
+    <li class="navhead"><a href="/" class="noline">Home</a></li>
 
     <li class="blank">&nbsp;</li>
     <li class="navhead">Documents</li>
-    <li><a href="/doc/go_spec.html">Language Specification</a></li>
-    <li><a href="/doc/go_mem.html">Memory Model</a></li>
-    <li><a href="/doc/go_tutorial.html">Tutorial</a></li>
-    <li><a href="/doc/effective_go.html">Effective Go</a></li>
-    <li><a href="/doc/go_faq.html">FAQ</a></li>
-    <li><a href="/doc/go_lang_faq.html">Language Design FAQ</a></li>
-    <li><a href="/doc/go_for_cpp_programmers.html">Go for C++ Programmers</a></li>
+    <li><a href="/doc/go_spec.html" class="noline">Language Specification</a></li>
+    <li><a href="/doc/go_mem.html" class="noline">Memory Model</a></li>
+    <li><a href="/doc/go_tutorial.html" class="noline">Tutorial</a></li>
+    <li><a href="/doc/effective_go.html" class="noline">Effective Go</a></li>
+    <li><a href="/doc/go_faq.html" class="noline">FAQ</a></li>
+    <li><a href="/doc/go_lang_faq.html" class="noline">Language Design FAQ</a></li>
+    <li><a href="/doc/go_for_cpp_programmers.html" class="noline">Go for C++ Programmers</a></li>
 
     <li class="blank">&nbsp;</li>
     <li class="navhead">How To</li>
-    <li><a href="/doc/install.html">Install Go</a></li>
-    <li><a href="/doc/contribute.html">Contribute code</a></li>
+    <li><a href="/doc/install.html" class="noline">Install Go</a></li>
+    <li><a href="/doc/contribute.html" class="noline">Contribute code</a></li>
 
     <li class="blank">&nbsp;</li>
     <li class="navhead">Programming</li>
-    <li><a href="/pkg">Package documentation</a></li>
+    <li><a href="/pkg" class="noline">Package documentation</a></li>
 
     <li class="blank">&nbsp;</li>
     <li class="navhead">Go code search</li>

lib/godoc/search.html

@@ -25,7 +25,7 @@
 			<h3>package {Pak.Name|html}</h3>
 			{.repeated section Files}
 				{.repeated section Infos}
-					<a href="{File.Path|html}?h={Query|html}#L{@|infoLine}">{File.Path|html}:{@|infoLine}</a>
+					<a href="{File.Path|html}?h={Query|html}#L{@|infoLine}" class="noline">{File.Path|html}:{@|infoLine}</a>
 					<pre>{@|infoSnippet}</pre>
 				{.end}
 			{.end}

src/cmd/godoc/godoc.go

@@ -349,6 +349,7 @@ func linkFmt(w io.Writer, x interface{}, format string) {
 
 
 var infoClasses = [nKinds]string{
+	"package",	// PackageClause
 	"import",	// ImportDecl
 	"const",	// ConstDecl
 	"type",	// TypeDecl

src/cmd/godoc/index.go

@@ -101,7 +101,8 @@ type SpotInfo uint32
 type SpotKind uint32
 
 const (
-	ImportDecl	SpotKind	= iota;
+	PackageClause	SpotKind	= iota;
+	ImportDecl;
 	ConstDecl;
 	TypeDecl;
 	VarDecl;
@@ -112,6 +113,15 @@ const (
 )
 
 
+func init() {
+	// sanity check: if nKinds is too large, the SpotInfo
+	// accessor functions may need to be updated
+	if nKinds > 8 {
+		panic();
+	}
+}
+
+
 // makeSpotInfo makes a SpotInfo.
 func makeSpotInfo(kind SpotKind, lori int, isIndex bool) SpotInfo {
 	// encode lori: bits [4..32)
@@ -159,8 +169,9 @@ type Pak struct {
 }
 
 
+// Paks are sorted by name (primary key) and by import path (secondary key).
 func (p *Pak) less(q *Pak) bool {
-	return p.Path < q.Path || p.Name < q.Name;
+	return p.Name < q.Name || p.Name == q.Name && p.Path < q.Path;
 }
 
 
@@ -196,24 +207,46 @@ type FileRun struct {
 }
 
 
+func (f *FileRun) Len() int {
+	return len(f.Infos);
+}
+func (f *FileRun) Less(i, j int) bool {
+	return f.Infos[i].less(f.Infos[j]);
+}
+func (f *FileRun) Swap(i, j int) {
+	f.Infos[i], f.Infos[j] = f.Infos[j], f.Infos[i];
+}
+
+
 // newFileRun allocates a new *FileRun from the Spot run [i, j) in h.
 func newFileRun(h *RunList, i, j int) interface{} {
 	file := h.At(i).(Spot).File;
-	lines := make([]SpotInfo, j-i);
-	prev := 0;
+	infos := make([]SpotInfo, j-i);
 	k := 0;
 	for ; i < j; i++ {
-		info := h.At(i).(Spot).Info;
-		// ignore line duplicates
-		// (if lori is a snippet index it is unique - no need to check IsIndex())
-		lori := info.Lori();
-		if lori != prev {
-			lines[k] = info;
-			prev = lori;
+		infos[k] = h.At(i).(Spot).Info;
 		k++;
 	}
+	run := &FileRun{file, infos};
+	// Spots were sorted by file to create this run.
+	// Within this run, sort them by line number.
+	sort.Sort(run);
+	// Remove duplicates: Both the lori and kind field
+	// must be the same for duplicate, and since the
+	// isIndex field is always the same for all infos
+	// in one list we can simply compare the entire
+	// info.
+	k = 0;
+	var prev SpotInfo;
+	for i, x := range infos {
+		if x != prev || i == 0 {
+			infos[k] = x;
+			k++;
+			prev = x;
 		}
-	return &FileRun{file, lines[0:k]};
+	}
+	run.Infos = infos[0:k];
+	return run;
 }
 
 
@@ -500,6 +533,17 @@ func (x *Indexer) Visit(node interface{}) bool {
 			ast.Walk(x, n.Type);
 		}
 
+	case *ast.File:
+		x.visitComment(n.Doc);
+		x.decl = nil;
+		x.visitIdent(PackageClause, n.Name);
+		for _, d := range n.Decls {
+			ast.Walk(x, d);
+		}
+		// don't visit package level comments for now
+		// to avoid duplicate visiting from individual
+		// nodes
+
 	default:
 		return true;
 	}