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-rw-r--r--src/cmd/cover/cover.go1146
1 files changed, 1146 insertions, 0 deletions
diff --git a/src/cmd/cover/cover.go b/src/cmd/cover/cover.go
new file mode 100644
index 0000000..5fd8b95
--- /dev/null
+++ b/src/cmd/cover/cover.go
@@ -0,0 +1,1146 @@
+// 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.
+
+package main
+
+import (
+ "bytes"
+ "encoding/json"
+ "flag"
+ "fmt"
+ "go/ast"
+ "go/parser"
+ "go/token"
+ "internal/coverage"
+ "internal/coverage/encodemeta"
+ "internal/coverage/slicewriter"
+ "io"
+ "log"
+ "os"
+ "path/filepath"
+ "sort"
+ "strconv"
+ "strings"
+
+ "cmd/internal/edit"
+ "cmd/internal/objabi"
+)
+
+const usageMessage = "" +
+ `Usage of 'go tool cover':
+Given a coverage profile produced by 'go test':
+ go test -coverprofile=c.out
+
+Open a web browser displaying annotated source code:
+ go tool cover -html=c.out
+
+Write out an HTML file instead of launching a web browser:
+ go tool cover -html=c.out -o coverage.html
+
+Display coverage percentages to stdout for each function:
+ go tool cover -func=c.out
+
+Finally, to generate modified source code with coverage annotations
+for a package (what go test -cover does):
+ go tool cover -mode=set -var=CoverageVariableName \
+ -pkgcfg=<config> -outfilelist=<file> file1.go ... fileN.go
+
+where -pkgcfg points to a file containing the package path,
+package name, module path, and related info from "go build",
+and -outfilelist points to a file containing the filenames
+of the instrumented output files (one per input file).
+See https://pkg.go.dev/internal/coverage#CoverPkgConfig for
+more on the package config.
+`
+
+func usage() {
+ fmt.Fprint(os.Stderr, usageMessage)
+ fmt.Fprintln(os.Stderr, "\nFlags:")
+ flag.PrintDefaults()
+ fmt.Fprintln(os.Stderr, "\n Only one of -html, -func, or -mode may be set.")
+ os.Exit(2)
+}
+
+var (
+ mode = flag.String("mode", "", "coverage mode: set, count, atomic")
+ varVar = flag.String("var", "GoCover", "name of coverage variable to generate")
+ output = flag.String("o", "", "file for output")
+ outfilelist = flag.String("outfilelist", "", "file containing list of output files (one per line) if -pkgcfg is in use")
+ htmlOut = flag.String("html", "", "generate HTML representation of coverage profile")
+ funcOut = flag.String("func", "", "output coverage profile information for each function")
+ pkgcfg = flag.String("pkgcfg", "", "enable full-package instrumentation mode using params from specified config file")
+)
+
+var pkgconfig coverage.CoverPkgConfig
+
+var outputfiles []string // set when -pkgcfg is in use
+
+var profile string // The profile to read; the value of -html or -func
+
+var counterStmt func(*File, string) string
+
+const (
+ atomicPackagePath = "sync/atomic"
+ atomicPackageName = "_cover_atomic_"
+)
+
+func main() {
+ objabi.AddVersionFlag()
+ flag.Usage = usage
+ flag.Parse()
+
+ // Usage information when no arguments.
+ if flag.NFlag() == 0 && flag.NArg() == 0 {
+ flag.Usage()
+ }
+
+ err := parseFlags()
+ if err != nil {
+ fmt.Fprintln(os.Stderr, err)
+ fmt.Fprintln(os.Stderr, `For usage information, run "go tool cover -help"`)
+ os.Exit(2)
+ }
+
+ // Generate coverage-annotated source.
+ if *mode != "" {
+ annotate(flag.Args())
+ return
+ }
+
+ // Output HTML or function coverage information.
+ if *htmlOut != "" {
+ err = htmlOutput(profile, *output)
+ } else {
+ err = funcOutput(profile, *output)
+ }
+
+ if err != nil {
+ fmt.Fprintf(os.Stderr, "cover: %v\n", err)
+ os.Exit(2)
+ }
+}
+
+// parseFlags sets the profile and counterStmt globals and performs validations.
+func parseFlags() error {
+ profile = *htmlOut
+ if *funcOut != "" {
+ if profile != "" {
+ return fmt.Errorf("too many options")
+ }
+ profile = *funcOut
+ }
+
+ // Must either display a profile or rewrite Go source.
+ if (profile == "") == (*mode == "") {
+ return fmt.Errorf("too many options")
+ }
+
+ if *varVar != "" && !token.IsIdentifier(*varVar) {
+ return fmt.Errorf("-var: %q is not a valid identifier", *varVar)
+ }
+
+ if *mode != "" {
+ switch *mode {
+ case "set":
+ counterStmt = setCounterStmt
+ case "count":
+ counterStmt = incCounterStmt
+ case "atomic":
+ counterStmt = atomicCounterStmt
+ case "regonly", "testmain":
+ counterStmt = nil
+ default:
+ return fmt.Errorf("unknown -mode %v", *mode)
+ }
+
+ if flag.NArg() == 0 {
+ return fmt.Errorf("missing source file(s)")
+ } else {
+ if *pkgcfg != "" {
+ if *output != "" {
+ return fmt.Errorf("please use '-outfilelist' flag instead of '-o'")
+ }
+ var err error
+ if outputfiles, err = readOutFileList(*outfilelist); err != nil {
+ return err
+ }
+ numInputs := len(flag.Args())
+ numOutputs := len(outputfiles)
+ if numOutputs != numInputs {
+ return fmt.Errorf("number of output files (%d) not equal to number of input files (%d)", numOutputs, numInputs)
+ }
+ if err := readPackageConfig(*pkgcfg); err != nil {
+ return err
+ }
+ return nil
+ } else {
+ if *outfilelist != "" {
+ return fmt.Errorf("'-outfilelist' flag applicable only when -pkgcfg used")
+ }
+ }
+ if flag.NArg() == 1 {
+ return nil
+ }
+ }
+ } else if flag.NArg() == 0 {
+ return nil
+ }
+ return fmt.Errorf("too many arguments")
+}
+
+func readOutFileList(path string) ([]string, error) {
+ data, err := os.ReadFile(path)
+ if err != nil {
+ return nil, fmt.Errorf("error reading -outfilelist file %q: %v", path, err)
+ }
+ return strings.Split(strings.TrimSpace(string(data)), "\n"), nil
+}
+
+func readPackageConfig(path string) error {
+ data, err := os.ReadFile(path)
+ if err != nil {
+ return fmt.Errorf("error reading pkgconfig file %q: %v", path, err)
+ }
+ if err := json.Unmarshal(data, &pkgconfig); err != nil {
+ return fmt.Errorf("error reading pkgconfig file %q: %v", path, err)
+ }
+ if pkgconfig.Granularity != "perblock" && pkgconfig.Granularity != "perfunc" {
+ return fmt.Errorf(`%s: pkgconfig requires perblock/perfunc value`, path)
+ }
+ return nil
+}
+
+// Block represents the information about a basic block to be recorded in the analysis.
+// Note: Our definition of basic block is based on control structures; we don't break
+// apart && and ||. We could but it doesn't seem important enough to bother.
+type Block struct {
+ startByte token.Pos
+ endByte token.Pos
+ numStmt int
+}
+
+// Package holds package-specific state.
+type Package struct {
+ mdb *encodemeta.CoverageMetaDataBuilder
+ counterLengths []int
+}
+
+// Function holds func-specific state.
+type Func struct {
+ units []coverage.CoverableUnit
+ counterVar string
+}
+
+// File is a wrapper for the state of a file used in the parser.
+// The basic parse tree walker is a method of this type.
+type File struct {
+ fset *token.FileSet
+ name string // Name of file.
+ astFile *ast.File
+ blocks []Block
+ content []byte
+ edit *edit.Buffer
+ mdb *encodemeta.CoverageMetaDataBuilder
+ fn Func
+ pkg *Package
+}
+
+// findText finds text in the original source, starting at pos.
+// It correctly skips over comments and assumes it need not
+// handle quoted strings.
+// It returns a byte offset within f.src.
+func (f *File) findText(pos token.Pos, text string) int {
+ b := []byte(text)
+ start := f.offset(pos)
+ i := start
+ s := f.content
+ for i < len(s) {
+ if bytes.HasPrefix(s[i:], b) {
+ return i
+ }
+ if i+2 <= len(s) && s[i] == '/' && s[i+1] == '/' {
+ for i < len(s) && s[i] != '\n' {
+ i++
+ }
+ continue
+ }
+ if i+2 <= len(s) && s[i] == '/' && s[i+1] == '*' {
+ for i += 2; ; i++ {
+ if i+2 > len(s) {
+ return 0
+ }
+ if s[i] == '*' && s[i+1] == '/' {
+ i += 2
+ break
+ }
+ }
+ continue
+ }
+ i++
+ }
+ return -1
+}
+
+// Visit implements the ast.Visitor interface.
+func (f *File) Visit(node ast.Node) ast.Visitor {
+ switch n := node.(type) {
+ case *ast.BlockStmt:
+ // If it's a switch or select, the body is a list of case clauses; don't tag the block itself.
+ if len(n.List) > 0 {
+ switch n.List[0].(type) {
+ case *ast.CaseClause: // switch
+ for _, n := range n.List {
+ clause := n.(*ast.CaseClause)
+ f.addCounters(clause.Colon+1, clause.Colon+1, clause.End(), clause.Body, false)
+ }
+ return f
+ case *ast.CommClause: // select
+ for _, n := range n.List {
+ clause := n.(*ast.CommClause)
+ f.addCounters(clause.Colon+1, clause.Colon+1, clause.End(), clause.Body, false)
+ }
+ return f
+ }
+ }
+ f.addCounters(n.Lbrace, n.Lbrace+1, n.Rbrace+1, n.List, true) // +1 to step past closing brace.
+ case *ast.IfStmt:
+ if n.Init != nil {
+ ast.Walk(f, n.Init)
+ }
+ ast.Walk(f, n.Cond)
+ ast.Walk(f, n.Body)
+ if n.Else == nil {
+ return nil
+ }
+ // The elses are special, because if we have
+ // if x {
+ // } else if y {
+ // }
+ // we want to cover the "if y". To do this, we need a place to drop the counter,
+ // so we add a hidden block:
+ // if x {
+ // } else {
+ // if y {
+ // }
+ // }
+ elseOffset := f.findText(n.Body.End(), "else")
+ if elseOffset < 0 {
+ panic("lost else")
+ }
+ f.edit.Insert(elseOffset+4, "{")
+ f.edit.Insert(f.offset(n.Else.End()), "}")
+
+ // We just created a block, now walk it.
+ // Adjust the position of the new block to start after
+ // the "else". That will cause it to follow the "{"
+ // we inserted above.
+ pos := f.fset.File(n.Body.End()).Pos(elseOffset + 4)
+ switch stmt := n.Else.(type) {
+ case *ast.IfStmt:
+ block := &ast.BlockStmt{
+ Lbrace: pos,
+ List: []ast.Stmt{stmt},
+ Rbrace: stmt.End(),
+ }
+ n.Else = block
+ case *ast.BlockStmt:
+ stmt.Lbrace = pos
+ default:
+ panic("unexpected node type in if")
+ }
+ ast.Walk(f, n.Else)
+ return nil
+ case *ast.SelectStmt:
+ // Don't annotate an empty select - creates a syntax error.
+ if n.Body == nil || len(n.Body.List) == 0 {
+ return nil
+ }
+ case *ast.SwitchStmt:
+ // Don't annotate an empty switch - creates a syntax error.
+ if n.Body == nil || len(n.Body.List) == 0 {
+ if n.Init != nil {
+ ast.Walk(f, n.Init)
+ }
+ if n.Tag != nil {
+ ast.Walk(f, n.Tag)
+ }
+ return nil
+ }
+ case *ast.TypeSwitchStmt:
+ // Don't annotate an empty type switch - creates a syntax error.
+ if n.Body == nil || len(n.Body.List) == 0 {
+ if n.Init != nil {
+ ast.Walk(f, n.Init)
+ }
+ ast.Walk(f, n.Assign)
+ return nil
+ }
+ case *ast.FuncDecl:
+ // Don't annotate functions with blank names - they cannot be executed.
+ // Similarly for bodyless funcs.
+ if n.Name.Name == "_" || n.Body == nil {
+ return nil
+ }
+ fname := n.Name.Name
+ // Skip AddUint32 and StoreUint32 if we're instrumenting
+ // sync/atomic itself in atomic mode (out of an abundance of
+ // caution), since as part of the instrumentation process we
+ // add calls to AddUint32/StoreUint32, and we don't want to
+ // somehow create an infinite loop.
+ //
+ // Note that in the current implementation (Go 1.20) both
+ // routines are assembly stubs that forward calls to the
+ // runtime/internal/atomic equivalents, hence the infinite
+ // loop scenario is purely theoretical (maybe if in some
+ // future implementation one of these functions might be
+ // written in Go). See #57445 for more details.
+ if atomicOnAtomic() && (fname == "AddUint32" || fname == "StoreUint32") {
+ return nil
+ }
+ // Determine proper function or method name.
+ if r := n.Recv; r != nil && len(r.List) == 1 {
+ t := r.List[0].Type
+ star := ""
+ if p, _ := t.(*ast.StarExpr); p != nil {
+ t = p.X
+ star = "*"
+ }
+ if p, _ := t.(*ast.Ident); p != nil {
+ fname = star + p.Name + "." + fname
+ }
+ }
+ walkBody := true
+ if *pkgcfg != "" {
+ f.preFunc(n, fname)
+ if pkgconfig.Granularity == "perfunc" {
+ walkBody = false
+ }
+ }
+ if walkBody {
+ ast.Walk(f, n.Body)
+ }
+ if *pkgcfg != "" {
+ flit := false
+ f.postFunc(n, fname, flit, n.Body)
+ }
+ return nil
+ case *ast.FuncLit:
+ // For function literals enclosed in functions, just glom the
+ // code for the literal in with the enclosing function (for now).
+ if f.fn.counterVar != "" {
+ return f
+ }
+
+ // Hack: function literals aren't named in the go/ast representation,
+ // and we don't know what name the compiler will choose. For now,
+ // just make up a descriptive name.
+ pos := n.Pos()
+ p := f.fset.File(pos).Position(pos)
+ fname := fmt.Sprintf("func.L%d.C%d", p.Line, p.Column)
+ if *pkgcfg != "" {
+ f.preFunc(n, fname)
+ }
+ if pkgconfig.Granularity != "perfunc" {
+ ast.Walk(f, n.Body)
+ }
+ if *pkgcfg != "" {
+ flit := true
+ f.postFunc(n, fname, flit, n.Body)
+ }
+ return nil
+ }
+ return f
+}
+
+func mkCounterVarName(idx int) string {
+ return fmt.Sprintf("%s_%d", *varVar, idx)
+}
+
+func mkPackageIdVar() string {
+ return *varVar + "P"
+}
+
+func mkMetaVar() string {
+ return *varVar + "M"
+}
+
+func mkPackageIdExpression() string {
+ ppath := pkgconfig.PkgPath
+ if hcid := coverage.HardCodedPkgID(ppath); hcid != -1 {
+ return fmt.Sprintf("uint32(%d)", uint32(hcid))
+ }
+ return mkPackageIdVar()
+}
+
+func (f *File) preFunc(fn ast.Node, fname string) {
+ f.fn.units = f.fn.units[:0]
+
+ // create a new counter variable for this function.
+ cv := mkCounterVarName(len(f.pkg.counterLengths))
+ f.fn.counterVar = cv
+}
+
+func (f *File) postFunc(fn ast.Node, funcname string, flit bool, body *ast.BlockStmt) {
+
+ // Tack on single counter write if we are in "perfunc" mode.
+ singleCtr := ""
+ if pkgconfig.Granularity == "perfunc" {
+ singleCtr = "; " + f.newCounter(fn.Pos(), fn.Pos(), 1)
+ }
+
+ // record the length of the counter var required.
+ nc := len(f.fn.units) + coverage.FirstCtrOffset
+ f.pkg.counterLengths = append(f.pkg.counterLengths, nc)
+
+ // FIXME: for windows, do we want "\" and not "/"? Need to test here.
+ // Currently filename is formed as packagepath + "/" + basename.
+ fnpos := f.fset.Position(fn.Pos())
+ ppath := pkgconfig.PkgPath
+ filename := ppath + "/" + filepath.Base(fnpos.Filename)
+
+ // The convention for cmd/cover is that if the go command that
+ // kicks off coverage specifies a local import path (e.g. "go test
+ // -cover ./thispackage"), the tool will capture full pathnames
+ // for source files instead of relative paths, which tend to work
+ // more smoothly for "go tool cover -html". See also issue #56433
+ // for more details.
+ if pkgconfig.Local {
+ filename = f.name
+ }
+
+ // Hand off function to meta-data builder.
+ fd := coverage.FuncDesc{
+ Funcname: funcname,
+ Srcfile: filename,
+ Units: f.fn.units,
+ Lit: flit,
+ }
+ funcId := f.mdb.AddFunc(fd)
+
+ hookWrite := func(cv string, which int, val string) string {
+ return fmt.Sprintf("%s[%d] = %s", cv, which, val)
+ }
+ if *mode == "atomic" {
+ hookWrite = func(cv string, which int, val string) string {
+ return fmt.Sprintf("%sStoreUint32(&%s[%d], %s)",
+ atomicPackagePrefix(), cv, which, val)
+ }
+ }
+
+ // Generate the registration hook sequence for the function. This
+ // sequence looks like
+ //
+ // counterVar[0] = <num_units>
+ // counterVar[1] = pkgId
+ // counterVar[2] = fnId
+ //
+ cv := f.fn.counterVar
+ regHook := hookWrite(cv, 0, strconv.Itoa(len(f.fn.units))) + " ; " +
+ hookWrite(cv, 1, mkPackageIdExpression()) + " ; " +
+ hookWrite(cv, 2, strconv.Itoa(int(funcId))) + singleCtr
+
+ // Insert the registration sequence into the function. We want this sequence to
+ // appear before any counter updates, so use a hack to ensure that this edit
+ // applies before the edit corresponding to the prolog counter update.
+
+ boff := f.offset(body.Pos())
+ ipos := f.fset.File(body.Pos()).Pos(boff)
+ ip := f.offset(ipos)
+ f.edit.Replace(ip, ip+1, string(f.content[ipos-1])+regHook+" ; ")
+
+ f.fn.counterVar = ""
+}
+
+func annotate(names []string) {
+ var p *Package
+ if *pkgcfg != "" {
+ pp := pkgconfig.PkgPath
+ pn := pkgconfig.PkgName
+ mp := pkgconfig.ModulePath
+ mdb, err := encodemeta.NewCoverageMetaDataBuilder(pp, pn, mp)
+ if err != nil {
+ log.Fatalf("creating coverage meta-data builder: %v\n", err)
+ }
+ p = &Package{
+ mdb: mdb,
+ }
+ }
+ // TODO: process files in parallel here if it matters.
+ for k, name := range names {
+ if strings.ContainsAny(name, "\r\n") {
+ // annotateFile uses '//line' directives, which don't permit newlines.
+ log.Fatalf("cover: input path contains newline character: %q", name)
+ }
+
+ last := false
+ if k == len(names)-1 {
+ last = true
+ }
+
+ fd := os.Stdout
+ isStdout := true
+ if *pkgcfg != "" {
+ var err error
+ fd, err = os.Create(outputfiles[k])
+ if err != nil {
+ log.Fatalf("cover: %s", err)
+ }
+ isStdout = false
+ } else if *output != "" {
+ var err error
+ fd, err = os.Create(*output)
+ if err != nil {
+ log.Fatalf("cover: %s", err)
+ }
+ isStdout = false
+ }
+ p.annotateFile(name, fd, last)
+ if !isStdout {
+ if err := fd.Close(); err != nil {
+ log.Fatalf("cover: %s", err)
+ }
+ }
+ }
+}
+
+func (p *Package) annotateFile(name string, fd io.Writer, last bool) {
+ fset := token.NewFileSet()
+ content, err := os.ReadFile(name)
+ if err != nil {
+ log.Fatalf("cover: %s: %s", name, err)
+ }
+ parsedFile, err := parser.ParseFile(fset, name, content, parser.ParseComments)
+ if err != nil {
+ log.Fatalf("cover: %s: %s", name, err)
+ }
+
+ file := &File{
+ fset: fset,
+ name: name,
+ content: content,
+ edit: edit.NewBuffer(content),
+ astFile: parsedFile,
+ }
+ if p != nil {
+ file.mdb = p.mdb
+ file.pkg = p
+ }
+
+ if *mode == "atomic" {
+ // Add import of sync/atomic immediately after package clause.
+ // We do this even if there is an existing import, because the
+ // existing import may be shadowed at any given place we want
+ // to refer to it, and our name (_cover_atomic_) is less likely to
+ // be shadowed. The one exception is if we're visiting the
+ // sync/atomic package itself, in which case we can refer to
+ // functions directly without an import prefix. See also #57445.
+ if pkgconfig.PkgPath != "sync/atomic" {
+ file.edit.Insert(file.offset(file.astFile.Name.End()),
+ fmt.Sprintf("; import %s %q", atomicPackageName, atomicPackagePath))
+ }
+ }
+ if pkgconfig.PkgName == "main" {
+ file.edit.Insert(file.offset(file.astFile.Name.End()),
+ "; import _ \"runtime/coverage\"")
+ }
+
+ if counterStmt != nil {
+ ast.Walk(file, file.astFile)
+ }
+ newContent := file.edit.Bytes()
+
+ if strings.ContainsAny(name, "\r\n") {
+ // This should have been checked by the caller already, but we double check
+ // here just to be sure we haven't missed a caller somewhere.
+ panic(fmt.Sprintf("annotateFile: name contains unexpected newline character: %q", name))
+ }
+ fmt.Fprintf(fd, "//line %s:1:1\n", name)
+ fd.Write(newContent)
+
+ // After printing the source tree, add some declarations for the
+ // counters etc. We could do this by adding to the tree, but it's
+ // easier just to print the text.
+ file.addVariables(fd)
+
+ // Emit a reference to the atomic package to avoid
+ // import and not used error when there's no code in a file.
+ if *mode == "atomic" {
+ fmt.Fprintf(fd, "var _ = %sLoadUint32\n", atomicPackagePrefix())
+ }
+
+ // Last file? Emit meta-data and converage config.
+ if last {
+ p.emitMetaData(fd)
+ }
+}
+
+// setCounterStmt returns the expression: __count[23] = 1.
+func setCounterStmt(f *File, counter string) string {
+ return fmt.Sprintf("%s = 1", counter)
+}
+
+// incCounterStmt returns the expression: __count[23]++.
+func incCounterStmt(f *File, counter string) string {
+ return fmt.Sprintf("%s++", counter)
+}
+
+// atomicCounterStmt returns the expression: atomic.AddUint32(&__count[23], 1)
+func atomicCounterStmt(f *File, counter string) string {
+ return fmt.Sprintf("%sAddUint32(&%s, 1)", atomicPackagePrefix(), counter)
+}
+
+// newCounter creates a new counter expression of the appropriate form.
+func (f *File) newCounter(start, end token.Pos, numStmt int) string {
+ var stmt string
+ if *pkgcfg != "" {
+ slot := len(f.fn.units) + coverage.FirstCtrOffset
+ if f.fn.counterVar == "" {
+ panic("internal error: counter var unset")
+ }
+ stmt = counterStmt(f, fmt.Sprintf("%s[%d]", f.fn.counterVar, slot))
+ stpos := f.fset.Position(start)
+ enpos := f.fset.Position(end)
+ stpos, enpos = dedup(stpos, enpos)
+ unit := coverage.CoverableUnit{
+ StLine: uint32(stpos.Line),
+ StCol: uint32(stpos.Column),
+ EnLine: uint32(enpos.Line),
+ EnCol: uint32(enpos.Column),
+ NxStmts: uint32(numStmt),
+ }
+ f.fn.units = append(f.fn.units, unit)
+ } else {
+ stmt = counterStmt(f, fmt.Sprintf("%s.Count[%d]", *varVar,
+ len(f.blocks)))
+ f.blocks = append(f.blocks, Block{start, end, numStmt})
+ }
+ return stmt
+}
+
+// addCounters takes a list of statements and adds counters to the beginning of
+// each basic block at the top level of that list. For instance, given
+//
+// S1
+// if cond {
+// S2
+// }
+// S3
+//
+// counters will be added before S1 and before S3. The block containing S2
+// will be visited in a separate call.
+// TODO: Nested simple blocks get unnecessary (but correct) counters
+func (f *File) addCounters(pos, insertPos, blockEnd token.Pos, list []ast.Stmt, extendToClosingBrace bool) {
+ // Special case: make sure we add a counter to an empty block. Can't do this below
+ // or we will add a counter to an empty statement list after, say, a return statement.
+ if len(list) == 0 {
+ f.edit.Insert(f.offset(insertPos), f.newCounter(insertPos, blockEnd, 0)+";")
+ return
+ }
+ // Make a copy of the list, as we may mutate it and should leave the
+ // existing list intact.
+ list = append([]ast.Stmt(nil), list...)
+ // We have a block (statement list), but it may have several basic blocks due to the
+ // appearance of statements that affect the flow of control.
+ for {
+ // Find first statement that affects flow of control (break, continue, if, etc.).
+ // It will be the last statement of this basic block.
+ var last int
+ end := blockEnd
+ for last = 0; last < len(list); last++ {
+ stmt := list[last]
+ end = f.statementBoundary(stmt)
+ if f.endsBasicSourceBlock(stmt) {
+ // If it is a labeled statement, we need to place a counter between
+ // the label and its statement because it may be the target of a goto
+ // and thus start a basic block. That is, given
+ // foo: stmt
+ // we need to create
+ // foo: ; stmt
+ // and mark the label as a block-terminating statement.
+ // The result will then be
+ // foo: COUNTER[n]++; stmt
+ // However, we can't do this if the labeled statement is already
+ // a control statement, such as a labeled for.
+ if label, isLabel := stmt.(*ast.LabeledStmt); isLabel && !f.isControl(label.Stmt) {
+ newLabel := *label
+ newLabel.Stmt = &ast.EmptyStmt{
+ Semicolon: label.Stmt.Pos(),
+ Implicit: true,
+ }
+ end = label.Pos() // Previous block ends before the label.
+ list[last] = &newLabel
+ // Open a gap and drop in the old statement, now without a label.
+ list = append(list, nil)
+ copy(list[last+1:], list[last:])
+ list[last+1] = label.Stmt
+ }
+ last++
+ extendToClosingBrace = false // Block is broken up now.
+ break
+ }
+ }
+ if extendToClosingBrace {
+ end = blockEnd
+ }
+ if pos != end { // Can have no source to cover if e.g. blocks abut.
+ f.edit.Insert(f.offset(insertPos), f.newCounter(pos, end, last)+";")
+ }
+ list = list[last:]
+ if len(list) == 0 {
+ break
+ }
+ pos = list[0].Pos()
+ insertPos = pos
+ }
+}
+
+// hasFuncLiteral reports the existence and position of the first func literal
+// in the node, if any. If a func literal appears, it usually marks the termination
+// of a basic block because the function body is itself a block.
+// Therefore we draw a line at the start of the body of the first function literal we find.
+// TODO: what if there's more than one? Probably doesn't matter much.
+func hasFuncLiteral(n ast.Node) (bool, token.Pos) {
+ if n == nil {
+ return false, 0
+ }
+ var literal funcLitFinder
+ ast.Walk(&literal, n)
+ return literal.found(), token.Pos(literal)
+}
+
+// statementBoundary finds the location in s that terminates the current basic
+// block in the source.
+func (f *File) statementBoundary(s ast.Stmt) token.Pos {
+ // Control flow statements are easy.
+ switch s := s.(type) {
+ case *ast.BlockStmt:
+ // Treat blocks like basic blocks to avoid overlapping counters.
+ return s.Lbrace
+ case *ast.IfStmt:
+ found, pos := hasFuncLiteral(s.Init)
+ if found {
+ return pos
+ }
+ found, pos = hasFuncLiteral(s.Cond)
+ if found {
+ return pos
+ }
+ return s.Body.Lbrace
+ case *ast.ForStmt:
+ found, pos := hasFuncLiteral(s.Init)
+ if found {
+ return pos
+ }
+ found, pos = hasFuncLiteral(s.Cond)
+ if found {
+ return pos
+ }
+ found, pos = hasFuncLiteral(s.Post)
+ if found {
+ return pos
+ }
+ return s.Body.Lbrace
+ case *ast.LabeledStmt:
+ return f.statementBoundary(s.Stmt)
+ case *ast.RangeStmt:
+ found, pos := hasFuncLiteral(s.X)
+ if found {
+ return pos
+ }
+ return s.Body.Lbrace
+ case *ast.SwitchStmt:
+ found, pos := hasFuncLiteral(s.Init)
+ if found {
+ return pos
+ }
+ found, pos = hasFuncLiteral(s.Tag)
+ if found {
+ return pos
+ }
+ return s.Body.Lbrace
+ case *ast.SelectStmt:
+ return s.Body.Lbrace
+ case *ast.TypeSwitchStmt:
+ found, pos := hasFuncLiteral(s.Init)
+ if found {
+ return pos
+ }
+ return s.Body.Lbrace
+ }
+ // If not a control flow statement, it is a declaration, expression, call, etc. and it may have a function literal.
+ // If it does, that's tricky because we want to exclude the body of the function from this block.
+ // Draw a line at the start of the body of the first function literal we find.
+ // TODO: what if there's more than one? Probably doesn't matter much.
+ found, pos := hasFuncLiteral(s)
+ if found {
+ return pos
+ }
+ return s.End()
+}
+
+// endsBasicSourceBlock reports whether s changes the flow of control: break, if, etc.,
+// or if it's just problematic, for instance contains a function literal, which will complicate
+// accounting due to the block-within-an expression.
+func (f *File) endsBasicSourceBlock(s ast.Stmt) bool {
+ switch s := s.(type) {
+ case *ast.BlockStmt:
+ // Treat blocks like basic blocks to avoid overlapping counters.
+ return true
+ case *ast.BranchStmt:
+ return true
+ case *ast.ForStmt:
+ return true
+ case *ast.IfStmt:
+ return true
+ case *ast.LabeledStmt:
+ return true // A goto may branch here, starting a new basic block.
+ case *ast.RangeStmt:
+ return true
+ case *ast.SwitchStmt:
+ return true
+ case *ast.SelectStmt:
+ return true
+ case *ast.TypeSwitchStmt:
+ return true
+ case *ast.ExprStmt:
+ // Calls to panic change the flow.
+ // We really should verify that "panic" is the predefined function,
+ // but without type checking we can't and the likelihood of it being
+ // an actual problem is vanishingly small.
+ if call, ok := s.X.(*ast.CallExpr); ok {
+ if ident, ok := call.Fun.(*ast.Ident); ok && ident.Name == "panic" && len(call.Args) == 1 {
+ return true
+ }
+ }
+ }
+ found, _ := hasFuncLiteral(s)
+ return found
+}
+
+// isControl reports whether s is a control statement that, if labeled, cannot be
+// separated from its label.
+func (f *File) isControl(s ast.Stmt) bool {
+ switch s.(type) {
+ case *ast.ForStmt, *ast.RangeStmt, *ast.SwitchStmt, *ast.SelectStmt, *ast.TypeSwitchStmt:
+ return true
+ }
+ return false
+}
+
+// funcLitFinder implements the ast.Visitor pattern to find the location of any
+// function literal in a subtree.
+type funcLitFinder token.Pos
+
+func (f *funcLitFinder) Visit(node ast.Node) (w ast.Visitor) {
+ if f.found() {
+ return nil // Prune search.
+ }
+ switch n := node.(type) {
+ case *ast.FuncLit:
+ *f = funcLitFinder(n.Body.Lbrace)
+ return nil // Prune search.
+ }
+ return f
+}
+
+func (f *funcLitFinder) found() bool {
+ return token.Pos(*f) != token.NoPos
+}
+
+// Sort interface for []block1; used for self-check in addVariables.
+
+type block1 struct {
+ Block
+ index int
+}
+
+type blockSlice []block1
+
+func (b blockSlice) Len() int { return len(b) }
+func (b blockSlice) Less(i, j int) bool { return b[i].startByte < b[j].startByte }
+func (b blockSlice) Swap(i, j int) { b[i], b[j] = b[j], b[i] }
+
+// offset translates a token position into a 0-indexed byte offset.
+func (f *File) offset(pos token.Pos) int {
+ return f.fset.Position(pos).Offset
+}
+
+// addVariables adds to the end of the file the declarations to set up the counter and position variables.
+func (f *File) addVariables(w io.Writer) {
+ if *pkgcfg != "" {
+ return
+ }
+ // Self-check: Verify that the instrumented basic blocks are disjoint.
+ t := make([]block1, len(f.blocks))
+ for i := range f.blocks {
+ t[i].Block = f.blocks[i]
+ t[i].index = i
+ }
+ sort.Sort(blockSlice(t))
+ for i := 1; i < len(t); i++ {
+ if t[i-1].endByte > t[i].startByte {
+ fmt.Fprintf(os.Stderr, "cover: internal error: block %d overlaps block %d\n", t[i-1].index, t[i].index)
+ // Note: error message is in byte positions, not token positions.
+ fmt.Fprintf(os.Stderr, "\t%s:#%d,#%d %s:#%d,#%d\n",
+ f.name, f.offset(t[i-1].startByte), f.offset(t[i-1].endByte),
+ f.name, f.offset(t[i].startByte), f.offset(t[i].endByte))
+ }
+ }
+
+ // Declare the coverage struct as a package-level variable.
+ fmt.Fprintf(w, "\nvar %s = struct {\n", *varVar)
+ fmt.Fprintf(w, "\tCount [%d]uint32\n", len(f.blocks))
+ fmt.Fprintf(w, "\tPos [3 * %d]uint32\n", len(f.blocks))
+ fmt.Fprintf(w, "\tNumStmt [%d]uint16\n", len(f.blocks))
+ fmt.Fprintf(w, "} {\n")
+
+ // Initialize the position array field.
+ fmt.Fprintf(w, "\tPos: [3 * %d]uint32{\n", len(f.blocks))
+
+ // A nice long list of positions. Each position is encoded as follows to reduce size:
+ // - 32-bit starting line number
+ // - 32-bit ending line number
+ // - (16 bit ending column number << 16) | (16-bit starting column number).
+ for i, block := range f.blocks {
+ start := f.fset.Position(block.startByte)
+ end := f.fset.Position(block.endByte)
+
+ start, end = dedup(start, end)
+
+ fmt.Fprintf(w, "\t\t%d, %d, %#x, // [%d]\n", start.Line, end.Line, (end.Column&0xFFFF)<<16|(start.Column&0xFFFF), i)
+ }
+
+ // Close the position array.
+ fmt.Fprintf(w, "\t},\n")
+
+ // Initialize the position array field.
+ fmt.Fprintf(w, "\tNumStmt: [%d]uint16{\n", len(f.blocks))
+
+ // A nice long list of statements-per-block, so we can give a conventional
+ // valuation of "percent covered". To save space, it's a 16-bit number, so we
+ // clamp it if it overflows - won't matter in practice.
+ for i, block := range f.blocks {
+ n := block.numStmt
+ if n > 1<<16-1 {
+ n = 1<<16 - 1
+ }
+ fmt.Fprintf(w, "\t\t%d, // %d\n", n, i)
+ }
+
+ // Close the statements-per-block array.
+ fmt.Fprintf(w, "\t},\n")
+
+ // Close the struct initialization.
+ fmt.Fprintf(w, "}\n")
+}
+
+// It is possible for positions to repeat when there is a line
+// directive that does not specify column information and the input
+// has not been passed through gofmt.
+// See issues #27530 and #30746.
+// Tests are TestHtmlUnformatted and TestLineDup.
+// We use a map to avoid duplicates.
+
+// pos2 is a pair of token.Position values, used as a map key type.
+type pos2 struct {
+ p1, p2 token.Position
+}
+
+// seenPos2 tracks whether we have seen a token.Position pair.
+var seenPos2 = make(map[pos2]bool)
+
+// dedup takes a token.Position pair and returns a pair that does not
+// duplicate any existing pair. The returned pair will have the Offset
+// fields cleared.
+func dedup(p1, p2 token.Position) (r1, r2 token.Position) {
+ key := pos2{
+ p1: p1,
+ p2: p2,
+ }
+
+ // We want to ignore the Offset fields in the map,
+ // since cover uses only file/line/column.
+ key.p1.Offset = 0
+ key.p2.Offset = 0
+
+ for seenPos2[key] {
+ key.p2.Column++
+ }
+ seenPos2[key] = true
+
+ return key.p1, key.p2
+}
+
+func (p *Package) emitMetaData(w io.Writer) {
+ if *pkgcfg == "" {
+ return
+ }
+
+ // Something went wrong if regonly/testmain mode is in effect and
+ // we have instrumented functions.
+ if counterStmt == nil && len(p.counterLengths) != 0 {
+ panic("internal error: seen functions with regonly/testmain")
+ }
+
+ // Emit package ID var.
+ fmt.Fprintf(w, "\nvar %sP uint32\n", *varVar)
+
+ // Emit all of the counter variables.
+ for k := range p.counterLengths {
+ cvn := mkCounterVarName(k)
+ fmt.Fprintf(w, "var %s [%d]uint32\n", cvn, p.counterLengths[k])
+ }
+
+ // Emit encoded meta-data.
+ var sws slicewriter.WriteSeeker
+ digest, err := p.mdb.Emit(&sws)
+ if err != nil {
+ log.Fatalf("encoding meta-data: %v", err)
+ }
+ p.mdb = nil
+ fmt.Fprintf(w, "var %s = [...]byte{\n", mkMetaVar())
+ payload := sws.BytesWritten()
+ for k, b := range payload {
+ fmt.Fprintf(w, " 0x%x,", b)
+ if k != 0 && k%8 == 0 {
+ fmt.Fprintf(w, "\n")
+ }
+ }
+ fmt.Fprintf(w, "}\n")
+
+ fixcfg := coverage.CoverFixupConfig{
+ Strategy: "normal",
+ MetaVar: mkMetaVar(),
+ MetaLen: len(payload),
+ MetaHash: fmt.Sprintf("%x", digest),
+ PkgIdVar: mkPackageIdVar(),
+ CounterPrefix: *varVar,
+ CounterGranularity: pkgconfig.Granularity,
+ CounterMode: *mode,
+ }
+ fixdata, err := json.Marshal(fixcfg)
+ if err != nil {
+ log.Fatalf("marshal fixupcfg: %v", err)
+ }
+ if err := os.WriteFile(pkgconfig.OutConfig, fixdata, 0666); err != nil {
+ log.Fatalf("error writing %s: %v", pkgconfig.OutConfig, err)
+ }
+}
+
+// atomicOnAtomic returns true if we're instrumenting
+// the sync/atomic package AND using atomic mode.
+func atomicOnAtomic() bool {
+ return *mode == "atomic" && pkgconfig.PkgPath == "sync/atomic"
+}
+
+// atomicPackagePrefix returns the import path prefix used to refer to
+// our special import of sync/atomic; this is either set to the
+// constant atomicPackageName plus a dot or the empty string if we're
+// instrumenting the sync/atomic package itself.
+func atomicPackagePrefix() string {
+ if atomicOnAtomic() {
+ return ""
+ }
+ return atomicPackageName + "."
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-29 20:38:06 +0000