cmd/cover: use golang.org/x/tools/cover directly

As suggested by Bryan in CL 249759, remove the forwarding aliases in
cmd/cover and use the symbols from golang.org/x/tools directly.

cmd/cover is not an importable package, so it is fine to remove these
exported symbols.

Change-Id: I887c5e9349f2dbe4c90be57f708412b844e18081
Reviewed-on: https://go-review.googlesource.com/c/go/+/304690
Trust: Tobias Klauser <[email protected]>
Reviewed-by: Bryan C. Mills <[email protected]>

Author: tklauser

src/cmd/cover/func.go

@@ -23,6 +23,8 @@ import (
 	"runtime"
 	"strings"
 	"text/tabwriter"
+
+	"golang.org/x/tools/cover"
 )
 
 // funcOutput takes two file names as arguments, a coverage profile to read as input and an output
@@ -38,7 +40,7 @@ import (
 //	total:		(statements)			91.9%
 
 func funcOutput(profile, outputFile string) error {
-	profiles, err := ParseProfiles(profile)
+	profiles, err := cover.ParseProfiles(profile)
 	if err != nil {
 		return err
 	}
@@ -144,7 +146,7 @@ func (v *FuncVisitor) Visit(node ast.Node) ast.Visitor {
 }
 
 // coverage returns the fraction of the statements in the function that were covered, as a numerator and denominator.
-func (f *FuncExtent) coverage(profile *Profile) (num, den int64) {
+func (f *FuncExtent) coverage(profile *cover.Profile) (num, den int64) {
 	// We could avoid making this n^2 overall by doing a single scan and annotating the functions,
 	// but the sizes of the data structures is never very large and the scan is almost instantaneous.
 	var covered, total int64
@@ -175,7 +177,7 @@ type Pkg struct {
 	}
 }
 
-func findPkgs(profiles []*Profile) (map[string]*Pkg, error) {
+func findPkgs(profiles []*cover.Profile) (map[string]*Pkg, error) {
 	// Run go list to find the location of every package we care about.
 	pkgs := make(map[string]*Pkg)
 	var list []string

src/cmd/cover/html.go

@@ -15,13 +15,15 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+
+	"golang.org/x/tools/cover"
 )
 
 // htmlOutput reads the profile data from profile and generates an HTML
 // coverage report, writing it to outfile. If outfile is empty,
 // it writes the report to a temporary file and opens it in a web browser.
 func htmlOutput(profile, outfile string) error {
-	profiles, err := ParseProfiles(profile)
+	profiles, err := cover.ParseProfiles(profile)
 	if err != nil {
 		return err
 	}
@@ -92,7 +94,7 @@ func htmlOutput(profile, outfile string) error {
 // percentCovered returns, as a percentage, the fraction of the statements in
 // the profile covered by the test run.
 // In effect, it reports the coverage of a given source file.
-func percentCovered(p *Profile) float64 {
+func percentCovered(p *cover.Profile) float64 {
 	var total, covered int64
 	for _, b := range p.Blocks {
 		total += int64(b.NumStmt)
@@ -108,7 +110,7 @@ func percentCovered(p *Profile) float64 {
 
 // htmlGen generates an HTML coverage report with the provided filename,
 // source code, and tokens, and writes it to the given Writer.
-func htmlGen(w io.Writer, src []byte, boundaries []Boundary) error {
+func htmlGen(w io.Writer, src []byte, boundaries []cover.Boundary) error {
 	dst := bufio.NewWriter(w)
 	for i := range src {
 		for len(boundaries) > 0 && boundaries[0].Offset == i {