cmd/go: use local state object in pkg workcmd

This commit modifies package `workcmd` to construct a new
modload.State object using the new constructor instead of the current
global `modload.LoaderState` variable.

This commit is part of the overall effort to eliminate global
modloader state.

[git-generate]
cd src/cmd/go/internal/workcmd
rf '
  inject modload.LoaderState runUse
  add sync.go:/func runSync\(/-0 var moduleLoaderState *modload.State
  ex {
    import "cmd/go/internal/modload";
    modload.LoaderState -> moduleLoaderState
  }
  add runSync://+0 moduleLoaderState := modload.NewState()
  add runEditwork://+0 moduleLoaderState := modload.NewState()
  add runInit://+0 moduleLoaderState := modload.NewState()
  add runUse://+0 moduleLoaderState := modload.NewState()
  add runVendor://+0 moduleLoaderState := modload.NewState()
  rm sync.go:/var moduleLoaderState \*modload.State/
'

Change-Id: Iadc4ffd19d15f80a694285c86adfc01f0d26bac7
Reviewed-on: https://go-review.googlesource.com/c/go/+/711129
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Michael Matloob <matloob@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

Author: jitsu-net

src/cmd/go/internal/workcmd/edit.go

@@ -132,6 +132,7 @@ func init() {
 }
 
 func runEditwork(ctx context.Context, cmd *base.Command, args []string) {
+	moduleLoaderState := modload.NewState()
 	if *editJSON && *editPrint {
 		base.Fatalf("go: cannot use both -json and -print")
 	}
@@ -143,8 +144,8 @@ func runEditwork(ctx context.Context, cmd *base.Command, args []string) {
 	if len(args) == 1 {
 		gowork = args[0]
 	} else {
-		modload.InitWorkfile(modload.LoaderState)
-		gowork = modload.WorkFilePath(modload.LoaderState)
+		modload.InitWorkfile(moduleLoaderState)
+		gowork = modload.WorkFilePath(moduleLoaderState)
 	}
 	if gowork == "" {
 		base.Fatalf("go: no go.work file found\n\t(run 'go work init' first or specify path using GOWORK environment variable)")

src/cmd/go/internal/workcmd/init.go

@@ -44,11 +44,12 @@ func init() {
 }
 
 func runInit(ctx context.Context, cmd *base.Command, args []string) {
-	modload.InitWorkfile(modload.LoaderState)
+	moduleLoaderState := modload.NewState()
+	modload.InitWorkfile(moduleLoaderState)
 
-	modload.LoaderState.ForceUseModules = true
+	moduleLoaderState.ForceUseModules = true
 
-	gowork := modload.WorkFilePath(modload.LoaderState)
+	gowork := modload.WorkFilePath(moduleLoaderState)
 	if gowork == "" {
 		gowork = filepath.Join(base.Cwd(), "go.work")
 	}
@@ -61,6 +62,6 @@ func runInit(ctx context.Context, cmd *base.Command, args []string) {
 	wf := new(modfile.WorkFile)
 	wf.Syntax = new(modfile.FileSyntax)
 	wf.AddGoStmt(goV)
-	workUse(ctx, gowork, wf, args)
+	workUse(moduleLoaderState, ctx, gowork, wf, args)
 	modload.WriteWorkFile(gowork, wf)
 }

src/cmd/go/internal/workcmd/sync.go

@@ -48,19 +48,20 @@ func init() {
 }
 
 func runSync(ctx context.Context, cmd *base.Command, args []string) {
-	modload.LoaderState.ForceUseModules = true
-	modload.InitWorkfile(modload.LoaderState)
-	if modload.WorkFilePath(modload.LoaderState) == "" {
+	moduleLoaderState := modload.NewState()
+	moduleLoaderState.ForceUseModules = true
+	modload.InitWorkfile(moduleLoaderState)
+	if modload.WorkFilePath(moduleLoaderState) == "" {
 		base.Fatalf("go: no go.work file found\n\t(run 'go work init' first or specify path using GOWORK environment variable)")
 	}
 
-	_, err := modload.LoadModGraph(modload.LoaderState, ctx, "")
+	_, err := modload.LoadModGraph(moduleLoaderState, ctx, "")
 	if err != nil {
-		toolchain.SwitchOrFatal(modload.LoaderState, ctx, err)
+		toolchain.SwitchOrFatal(moduleLoaderState, ctx, err)
 	}
 	mustSelectFor := map[module.Version][]module.Version{}
 
-	mms := modload.LoaderState.MainModules
+	mms := moduleLoaderState.MainModules
 
 	opts := modload.PackageOpts{
 		Tags:                     imports.AnyTags(),
@@ -73,7 +74,7 @@ func runSync(ctx context.Context, cmd *base.Command, args []string) {
 	}
 	for _, m := range mms.Versions() {
 		opts.MainModule = m
-		_, pkgs := modload.LoadPackages(modload.LoaderState, ctx, opts, "all")
+		_, pkgs := modload.LoadPackages(moduleLoaderState, ctx, opts, "all")
 		opts.MainModule = module.Version{} // reset
 
 		var (
@@ -91,7 +92,7 @@ func runSync(ctx context.Context, cmd *base.Command, args []string) {
 		mustSelectFor[m] = mustSelect
 	}
 
-	workFilePath := modload.WorkFilePath(modload.LoaderState) // save go.work path because EnterModule clobbers it.
+	workFilePath := modload.WorkFilePath(moduleLoaderState) // save go.work path because EnterModule clobbers it.
 
 	var goV string
 	for _, m := range mms.Versions() {
@@ -104,7 +105,7 @@ func runSync(ctx context.Context, cmd *base.Command, args []string) {
 
 		// Use EnterModule to reset the global state in modload to be in
 		// single-module mode using the modroot of m.
-		modload.EnterModule(modload.LoaderState, ctx, mms.ModRoot(m))
+		modload.EnterModule(moduleLoaderState, ctx, mms.ModRoot(m))
 
 		// Edit the build list in the same way that 'go get' would if we
 		// requested the relevant module versions explicitly.
@@ -114,12 +115,12 @@ func runSync(ctx context.Context, cmd *base.Command, args []string) {
 		// so we don't write some go.mods with the "before" toolchain
 		// and others with the "after" toolchain. If nothing else, that
 		// discrepancy could show up in auto-recorded toolchain lines.
-		changed, err := modload.EditBuildList(modload.LoaderState, ctx, nil, mustSelectFor[m])
+		changed, err := modload.EditBuildList(moduleLoaderState, ctx, nil, mustSelectFor[m])
 		if err != nil {
 			continue
 		}
 		if changed {
-			modload.LoadPackages(modload.LoaderState, ctx, modload.PackageOpts{
+			modload.LoadPackages(moduleLoaderState, ctx, modload.PackageOpts{
 				Tags:                     imports.AnyTags(),
 				Tidy:                     true,
 				VendorModulesInGOROOTSrc: true,
@@ -129,9 +130,9 @@ func runSync(ctx context.Context, cmd *base.Command, args []string) {
 				SilenceMissingStdImports: true,
 				SilencePackageErrors:     true,
 			}, "all")
-			modload.WriteGoMod(modload.LoaderState, ctx, modload.WriteOpts{})
+			modload.WriteGoMod(moduleLoaderState, ctx, modload.WriteOpts{})
 		}
-		goV = gover.Max(goV, modload.LoaderState.MainModules.GoVersion(modload.LoaderState))
+		goV = gover.Max(goV, moduleLoaderState.MainModules.GoVersion(moduleLoaderState))
 	}
 
 	wf, err := modload.ReadWorkFile(workFilePath)

src/cmd/go/internal/workcmd/use.go

@@ -61,21 +61,22 @@ func init() {
 }
 
 func runUse(ctx context.Context, cmd *base.Command, args []string) {
-	modload.LoaderState.ForceUseModules = true
-	modload.InitWorkfile(modload.LoaderState)
-	gowork := modload.WorkFilePath(modload.LoaderState)
+	moduleLoaderState := modload.NewState()
+	moduleLoaderState.ForceUseModules = true
+	modload.InitWorkfile(moduleLoaderState)
+	gowork := modload.WorkFilePath(moduleLoaderState)
 	if gowork == "" {
 		base.Fatalf("go: no go.work file found\n\t(run 'go work init' first or specify path using GOWORK environment variable)")
 	}
 	wf, err := modload.ReadWorkFile(gowork)
 	if err != nil {
 		base.Fatal(err)
 	}
-	workUse(ctx, gowork, wf, args)
+	workUse(moduleLoaderState, ctx, gowork, wf, args)
 	modload.WriteWorkFile(gowork, wf)
 }
 
-func workUse(ctx context.Context, gowork string, wf *modfile.WorkFile, args []string) {
+func workUse(loaderstate *modload.State, ctx context.Context, gowork string, wf *modfile.WorkFile, args []string) {
 	workDir := filepath.Dir(gowork) // absolute, since gowork itself is absolute
 
 	haveDirs := make(map[string][]string) // absolute → original(s)
@@ -94,7 +95,7 @@ func workUse(ctx context.Context, gowork string, wf *modfile.WorkFile, args []st
 	// all entries for the absolute path should be removed.
 	keepDirs := make(map[string]string)
 
-	sw := toolchain.NewSwitcher(modload.LoaderState)
+	sw := toolchain.NewSwitcher(loaderstate)
 
 	// lookDir updates the entry in keepDirs for the directory dir,
 	// which is either absolute or relative to the current working directory

src/cmd/go/internal/workcmd/vendor.go

@@ -46,10 +46,11 @@ func init() {
 }
 
 func runVendor(ctx context.Context, cmd *base.Command, args []string) {
-	modload.InitWorkfile(modload.LoaderState)
-	if modload.WorkFilePath(modload.LoaderState) == "" {
+	moduleLoaderState := modload.NewState()
+	modload.InitWorkfile(moduleLoaderState)
+	if modload.WorkFilePath(moduleLoaderState) == "" {
 		base.Fatalf("go: no go.work file found\n\t(run 'go work init' first or specify path using GOWORK environment variable)")
 	}
 
-	modcmd.RunVendor(modload.LoaderState, ctx, vendorE, vendorO, args)
+	modcmd.RunVendor(moduleLoaderState, ctx, vendorE, vendorO, args)
 }