// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// This file provides support for parsing coverage profiles
// generated by "go test -coverprofile=cover.out".
// It is a copy of golang.org/x/tools/cover/profile.go.
package main
import (
"bufio"
"fmt"
"math"
"os"
"regexp"
"sort"
"strconv"
"strings"
)
// Profile represents the profiling data for a specific file.
type Profile struct {
FileName string
Mode string
Blocks []ProfileBlock
}
// ProfileBlock represents a single block of profiling data.
type ProfileBlock struct {
StartLine, StartCol int
EndLine, EndCol int
NumStmt, Count int
}
type byFileName []*Profile
func (p byFileName) Len() int { return len(p) }
func (p byFileName) Less(i, j int) bool { return p[i].FileName < p[j].FileName }
func (p byFileName) Swap(i, j int) { p[i], p[j] = p[j], p[i] }
// ParseProfiles parses profile data in the specified file and returns a
// Profile for each source file described therein.
func ParseProfiles(fileName string) ([]*Profile, error) {
pf, err := os.Open(fileName)
if err != nil {
return nil, err
}
defer pf.Close()
files := make(map[string]*Profile)
buf := bufio.NewReader(pf)
// First line is "mode: foo", where foo is "set", "count", or "atomic".
// Rest of file is in the format
// encoding/base64/base64.go:34.44,37.40 3 1
// where the fields are: name.go:line.column,line.column numberOfStatements count
s := bufio.NewScanner(buf)
mode := ""
for s.Scan() {
line := s.Text()
if mode == "" {
const p = "mode: "
if !strings.HasPrefix(line, p) || line == p {
return nil, fmt.Errorf("bad mode line: %v", line)
}
mode = line[len(p):]
continue
}
m := lineRe.FindStringSubmatch(line)
if m == nil {
return nil, fmt.Errorf("line %q doesn't match expected format: %v", m, lineRe)
}
fn := m[1]
p := files[fn]
if p == nil {
p = &Profile{
FileName: fn,
Mode: mode,
}
files[fn] = p
}
p.Blocks = append(p.Blocks, ProfileBlock{
StartLine: toInt(m[2]),
StartCol: toInt(m[3]),
EndLine: toInt(m[4]),
EndCol: toInt(m[5]),
NumStmt: toInt(m[6]),
Count: toInt(m[7]),
})
}
if err := s.Err(); err != nil {
return nil, err
}
for _, p := range files {
sort.Sort(blocksByStart(p.Blocks))
}
// Generate a sorted slice.
profiles := make([]*Profile, 0, len(files))
for _, profile := range files {
profiles = append(profiles, profile)
}
sort.Sort(byFileName(profiles))
return profiles, nil
}
type blocksByStart []ProfileBlock
func (b blocksByStart) Len() int { return len(b) }
func (b blocksByStart) Swap(i, j int) { b[i], b[j] = b[j], b[i] }
func (b blocksByStart) Less(i, j int) bool {
bi, bj := b[i], b[j]
return bi.StartLine < bj.StartLine || bi.StartLine == bj.StartLine && bi.StartCol < bj.StartCol
}
var lineRe = regexp.MustCompile(`^(.+):([0-9]+).([0-9]+),([0-9]+).([0-9]+) ([0-9]+) ([0-9]+)$`)
func toInt(s string) int {
i, err := strconv.Atoi(s)
if err != nil {
panic(err)
}
return i
}
// Boundary represents the position in a source file of the beginning or end of a
// block as reported by the coverage profile. In HTML mode, it will correspond to
// the opening or closing of a <span> tag and will be used to colorize the source
type Boundary struct {
Offset int // Location as a byte offset in the source file.
Start bool // Is this the start of a block?
Count int // Event count from the cover profile.
Norm float64 // Count normalized to [0..1].
}
// Boundaries returns a Profile as a set of Boundary objects within the provided src.
func (p *Profile) Boundaries(src []byte) (boundaries []Boundary) {
// Find maximum count.
max := 0
for _, b := range p.Blocks {
if b.Count > max {
max = b.Count
}
}
// Divisor for normalization.
divisor := math.Log(float64(max))
// boundary returns a Boundary, populating the Norm field with a normalized Count.
boundary := func(offset int, start bool, count int) Boundary {
b := Boundary{Offset: offset, Start: start, Count: count}
if !start || count == 0 {
return b
}
if max <= 1 {
b.Norm = 0.8 // Profile is in"set" mode; we want a heat map. Use cov8 in the CSS.
} else if count > 0 {
b.Norm = math.Log(float64(count)) / divisor
}
return b
}
line, col := 1, 2 // TODO: Why is this 2?
for si, bi := 0, 0; si < len(src) && bi < len(p.Blocks); {
b := p.Blocks[bi]
if b.StartLine == line && b.StartCol == col {
boundaries = append(boundaries, boundary(si, true, b.Count))
}
if b.EndLine == line && b.EndCol == col || line > b.EndLine {
boundaries = append(boundaries, boundary(si, false, 0))
bi++
continue // Don't advance through src; maybe the next block starts here.
}
if src[si] == '\n' {
line++
col = 0
}
col++
si++
}
sort.Sort(boundariesByPos(boundaries))
return
}
type boundariesByPos []Boundary
func (b boundariesByPos) Len() int { return len(b) }
func (b boundariesByPos) Swap(i, j int) { b[i], b[j] = b[j], b[i] }
func (b boundariesByPos) Less(i, j int) bool {
if b[i].Offset == b[j].Offset {
return !b[i].Start && b[j].Start
}
return b[i].Offset < b[j].Offset
}