Implement location-based sort order

cmd/gocov-html/main.go

@@ -42,6 +42,7 @@ func main() {
 	listThemes := flag.Bool("lt", false, "list available themes")
 	theme := flag.String("t", "golang", "theme to use for rendering")
 	reverseOrder := flag.Bool("r", false, "put lower coverage functions on top")
+	sortOrder := flag.String("sort", "high-coverage", "sort functions by high-coverage, low-coverage or location")
 	maxCoverage := flag.Uint64("cmax", 100, "only show functions whose coverage is greater than cmax")
 	minCoverage := flag.Uint64("cmin", 0, "only show functions whose coverage is smaller than cmin")
 
@@ -81,6 +82,15 @@ func main() {
 		return
 	}
 
+	var sortOrderOpt themes.SortOrder = themes.SortOrder(*sortOrder)
+	if !sortOrderOpt.Valid() {
+		log.Fatalf("Invalid sort order: %q\n", sortOrderOpt)
+	}
+
+	if *reverseOrder {
+		sortOrderOpt = themes.SortOrderLowCoverage
+	}
+
 	switch flag.NArg() {
 	case 0:
 		r = os.Stdin
@@ -94,10 +104,10 @@ func main() {
 	}
 
 	opts := themes.ReportOptions{
-		LowCoverageOnTop: *reverseOrder,
-		Stylesheet:       *css,
-		CoverageMin:      uint8(*minCoverage),
-		CoverageMax:      uint8(*maxCoverage),
+		SortOrder:   sortOrderOpt,
+		Stylesheet:  *css,
+		CoverageMin: uint8(*minCoverage),
+		CoverageMax: uint8(*maxCoverage),
 	}
 	if err := themes.HTMLReportCoverage(r, opts); err != nil {
 		log.Fatal(err)

pkg/themes/report.go

@@ -21,8 +21,8 @@ import (
 // ReportOptions holds various options used when generating the final
 // HTML report.
 type ReportOptions struct {
-	// LowCoverageOnTop puts low coverage functions first.
-	LowCoverageOnTop bool
+	// SortOrder decides how to sort functions
+	SortOrder SortOrder
 	// Stylesheet is the path to a custom CSS file.
 	Stylesheet string
 	// CoverageMin filters out all functions whose code coverage is smaller than it is.
@@ -31,6 +31,21 @@ type ReportOptions struct {
 	CoverageMax uint8
 }
 
+type SortOrder string
+
+const SortOrderHighCoverage SortOrder = "high-coverage"
+const SortOrderLowCoverage SortOrder = "low-coverage"
+const SortOrderLocation SortOrder = "location"
+
+func (so SortOrder) Valid() bool {
+	switch so {
+	case SortOrderHighCoverage, SortOrderLowCoverage, SortOrderLocation:
+		return true
+	default:
+		return false
+	}
+}
+
 type report struct {
 	ReportOptions
 	packages []*gocov.Package
@@ -45,14 +60,6 @@ func unmarshalJSON(data []byte) (packages []*gocov.Package, err error) {
 	return
 }
 
-type reverse struct {
-	sort.Interface
-}
-
-func (r reverse) Less(i, j int) bool {
-	return r.Interface.Less(j, i)
-}
-
 // NewReport creates a new report.
 func newReport() (r *report) {
 	r = &report{}
@@ -98,10 +105,13 @@ func buildReportPackage(pkg *gocov.Package, r *report) reportPackage {
 		rv.TotalStatements += len(fn.Statements)
 		rv.ReachedStatements += reached
 	}
-	if r.LowCoverageOnTop {
+	switch r.SortOrder {
+	case SortOrderHighCoverage:
 		sort.Sort(rv.Functions)
-	} else {
-		sort.Sort(reverse{rv.Functions})
+	case SortOrderLowCoverage:
+		sort.Sort(sort.Reverse(rv.Functions))
+	case SortOrderLocation:
+		sort.Sort(locationOrderedFunctionList(rv.Functions))
 	}
 	return rv
 }
@@ -333,6 +343,23 @@ func (f reportFunction) Lines() []functionLine {
 	return fls
 }
 
+type locationOrderedFunctionList reportFunctionList
+
+func (l locationOrderedFunctionList) Len() int {
+	return len(l)
+}
+
+func (l locationOrderedFunctionList) Less(i, j int) bool {
+	if l[i].File == l[j].File {
+		return l[i].Start < l[j].Start
+	}
+	return l[i].File < l[j].File
+}
+
+func (l locationOrderedFunctionList) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}
+
 // reportFunctionList is a list of functions for a report.
 type reportFunctionList []reportFunction