cmd/go: propagate Context arguments through modfetch methods

For #56886.
For #38714.

Change-Id: I15c4a8673407d3423d7e203d645c6d0fb780d192
Reviewed-on: https://go-review.googlesource.com/c/go/+/452456
Reviewed-by: Michael Matloob <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Auto-Submit: Bryan Mills <[email protected]>
Run-TryBot: Bryan Mills <[email protected]>

src/cmd/go/internal/cfg/cfg.go

@@ -8,6 +8,7 @@ package cfg
 
 import (
 	"bytes"
+	"context"
 	"fmt"
 	"go/build"
 	"internal/buildcfg"
@@ -573,3 +574,23 @@ func gopath(ctxt build.Context) string {
 	GoPathError = fmt.Sprintf("%s is not set", env)
 	return ""
 }
+
+// WithBuildXWriter returns a Context in which BuildX output is written
+// to given io.Writer.
+func WithBuildXWriter(ctx context.Context, xLog io.Writer) context.Context {
+	return context.WithValue(ctx, buildXContextKey{}, xLog)
+}
+
+type buildXContextKey struct{}
+
+// BuildXWriter returns nil if BuildX is false, or
+// the writer to which BuildX output should be written otherwise.
+func BuildXWriter(ctx context.Context) (io.Writer, bool) {
+	if !BuildX {
+		return nil, false
+	}
+	if v := ctx.Value(buildXContextKey{}); v != nil {
+		return v.(io.Writer), true
+	}
+	return os.Stderr, true
+}

src/cmd/go/internal/load/pkg.go

@@ -2024,7 +2024,7 @@ func (p *Package) load(ctx context.Context, opts PackageOpts, path string, stk *
 		// Consider starting this as a background goroutine and retrieving the result
 		// asynchronously when we're actually ready to build the package, or when we
 		// actually need to evaluate whether the package's metadata is stale.
-		p.setBuildInfo(opts.AutoVCS)
+		p.setBuildInfo(ctx, opts.AutoVCS)
 	}
 
 	// If cgo is not enabled, ignore cgo supporting sources
@@ -2267,7 +2267,7 @@ var vcsStatusCache par.ErrCache[string, vcs.Status]
 //
 // Note that the GoVersion field is not set here to avoid encoding it twice.
 // It is stored separately in the binary, mostly for historical reasons.
-func (p *Package) setBuildInfo(autoVCS bool) {
+func (p *Package) setBuildInfo(ctx context.Context, autoVCS bool) {
 	setPkgErrorf := func(format string, args ...any) {
 		if p.Error == nil {
 			p.Error = &PackageError{Err: fmt.Errorf(format, args...)}
@@ -2288,7 +2288,7 @@ func (p *Package) setBuildInfo(autoVCS bool) {
 		if mi.Replace != nil {
 			dm.Replace = debugModFromModinfo(mi.Replace)
 		} else if mi.Version != "" {
-			dm.Sum = modfetch.Sum(module.Version{Path: mi.Path, Version: mi.Version})
+			dm.Sum = modfetch.Sum(ctx, module.Version{Path: mi.Path, Version: mi.Version})
 		}
 		return dm
 	}
@@ -3280,7 +3280,7 @@ func PackagesAndErrorsOutsideModule(ctx context.Context, opts PackageOpts, args
 		return nil, fmt.Errorf("%s: %w", args[0], err)
 	}
 	rootMod := qrs[0].Mod
-	data, err := modfetch.GoMod(rootMod.Path, rootMod.Version)
+	data, err := modfetch.GoMod(ctx, rootMod.Path, rootMod.Version)
 	if err != nil {
 		return nil, fmt.Errorf("%s: %w", args[0], err)
 	}

src/cmd/go/internal/modcmd/download.go

@@ -283,18 +283,18 @@ func runDownload(ctx context.Context, cmd *base.Command, args []string) {
 // leaving the results (including any error) in m itself.
 func DownloadModule(ctx context.Context, m *ModuleJSON) {
 	var err error
-	_, file, err := modfetch.InfoFile(m.Path, m.Version)
+	_, file, err := modfetch.InfoFile(ctx, m.Path, m.Version)
 	if err != nil {
 		m.Error = err.Error()
 		return
 	}
 	m.Info = file
-	m.GoMod, err = modfetch.GoModFile(m.Path, m.Version)
+	m.GoMod, err = modfetch.GoModFile(ctx, m.Path, m.Version)
 	if err != nil {
 		m.Error = err.Error()
 		return
 	}
-	m.GoModSum, err = modfetch.GoModSum(m.Path, m.Version)
+	m.GoModSum, err = modfetch.GoModSum(ctx, m.Path, m.Version)
 	if err != nil {
 		m.Error = err.Error()
 		return
@@ -305,7 +305,7 @@ func DownloadModule(ctx context.Context, m *ModuleJSON) {
 		m.Error = err.Error()
 		return
 	}
-	m.Sum = modfetch.Sum(mod)
+	m.Sum = modfetch.Sum(ctx, mod)
 	m.Dir, err = modfetch.Download(ctx, mod)
 	if err != nil {
 		m.Error = err.Error()

src/cmd/go/internal/modcmd/edit.go

@@ -248,7 +248,7 @@ func runEdit(ctx context.Context, cmd *base.Command, args []string) {
 
 	// Make a best-effort attempt to acquire the side lock, only to exclude
 	// previous versions of the 'go' command from making simultaneous edits.
-	if unlock, err := modfetch.SideLock(); err == nil {
+	if unlock, err := modfetch.SideLock(ctx); err == nil {
 		defer unlock()
 	}
 

src/cmd/go/internal/modcmd/verify.go

@@ -67,7 +67,7 @@ func runVerify(ctx context.Context, cmd *base.Command, args []string) {
 		errsChans[i] = errsc
 		mod := mod // use a copy to avoid data races
 		go func() {
-			errsc <- verifyMod(mod)
+			errsc <- verifyMod(ctx, mod)
 			<-sem
 		}()
 	}
@@ -85,13 +85,13 @@ func runVerify(ctx context.Context, cmd *base.Command, args []string) {
 	}
 }
 
-func verifyMod(mod module.Version) []error {
+func verifyMod(ctx context.Context, mod module.Version) []error {
 	var errs []error
-	zip, zipErr := modfetch.CachePath(mod, "zip")
+	zip, zipErr := modfetch.CachePath(ctx, mod, "zip")
 	if zipErr == nil {
 		_, zipErr = os.Stat(zip)
 	}
-	dir, dirErr := modfetch.DownloadDir(mod)
+	dir, dirErr := modfetch.DownloadDir(ctx, mod)
 	data, err := os.ReadFile(zip + "hash")
 	if err != nil {
 		if zipErr != nil && errors.Is(zipErr, fs.ErrNotExist) &&