cmd/go: address review comments

Address review comments from earlier CLs.
These are changes I was too scared to try to push
down into the original CLs (thanks, Git).

Change-Id: I0e428fad73d71bd2a7d08178cf2e856de3cef19f
Reviewed-on: https://go-review.googlesource.com/36257
Reviewed-by: David Crawshaw <[email protected]>

Author: rsc

src/cmd/dist/deps.go

@@ -8,8 +8,6 @@ package base
 
 import (
 	"bytes"
-	"cmd/go/internal/cfg"
-	"cmd/go/internal/str"
 	"errors"
 	"flag"
 	"fmt"
@@ -19,6 +17,9 @@ import (
 	"os/exec"
 	"strings"
 	"sync"
+
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/str"
 )
 
 // A Command is an implementation of a go command

src/cmd/go/internal/base/base.go

@@ -5,8 +5,10 @@
 package base
 
 import (
-	"cmd/go/internal/str"
 	"flag"
+
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/str"
 )
 
 // A StringsFlag is a command-line flag that interprets its argument
@@ -28,6 +30,6 @@ func (v *StringsFlag) String() string {
 
 // AddBuildFlagsNX adds the -n and -x build flags to the flag set.
 func AddBuildFlagsNX(flags *flag.FlagSet) {
-	flags.BoolVar(&BuildN, "n", false, "")
-	flags.BoolVar(&BuildX, "x", false, "")
+	flags.BoolVar(&cfg.BuildN, "n", false, "")
+	flags.BoolVar(&cfg.BuildX, "x", false, "")
 }

src/cmd/go/internal/base/flag.go

@@ -10,7 +10,15 @@ import (
 	"strings"
 )
 
-var Cwd, _ = os.Getwd()
+func getwd() string {
+	wd, err := os.Getwd()
+	if err != nil {
+		Fatalf("cannot determine current directory: %v", err)
+	}
+	return wd
+}
+
+var Cwd = getwd()
 
 // ShortPath returns an absolute or relative name for path, whatever is shorter.
 func ShortPath(path string) string {

src/cmd/go/internal/base/path.go

@@ -7,7 +7,6 @@
 package cfg
 
 import (
-	"flag"
 	"go/build"
 	"os"
 	"path/filepath"
@@ -30,14 +29,18 @@ var (
 	BuildRace              bool               // -race flag
 	BuildToolexec          []string           // -toolexec flag
 	BuildToolchainName     string
-	BuildToolchainCompiler string
-	BuildToolchainLinker   string
+	BuildToolchainCompiler func() string
+	BuildToolchainLinker   func() string
 	BuildV                 bool // -v flag
 	BuildWork              bool // -work flag
 	BuildX                 bool // -x flag
-
 )
 
+func init() {
+	BuildToolchainCompiler = func() string { return "missing-compiler" }
+	BuildToolchainLinker = func() string { return "missing-linker" }
+}
+
 // The test coverage mode affects package loading. Sigh.
 var TestCoverMode string // -covermode flag
 
@@ -50,8 +53,10 @@ type EnvVar struct {
 // OrigEnv is the original environment of the program at startup.
 var OrigEnv []string
 
-// NewEnv is the new environment for running commands.
-var NewEnv []EnvVar
+// CmdEnv is the new environment for running go tool commands.
+// User binaries (during go test or go run) are run with OrigEnv,
+// not CmdEnv.
+var CmdEnv []EnvVar
 
 // Global build parameters (used during package load)
 var (
@@ -61,12 +66,6 @@ var (
 	Gopath    []string
 )
 
-// AddBuildFlagsNX adds the -n and -x build flags to the flag set.
-func AddBuildFlagsNX(flags *flag.FlagSet) {
-	flags.BoolVar(&BuildN, "n", false, "")
-	flags.BoolVar(&BuildX, "x", false, "")
-}
-
 var (
 	GOROOT    = filepath.Clean(runtime.GOROOT())
 	GOBIN     = os.Getenv("GOBIN")

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

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Package clean implements the ``go clean'' command.
 package clean
 
 import (

src/cmd/go/internal/clean/clean.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Package doc implements the ``go doc'' command.
 package doc
 
 import (

src/cmd/go/internal/doc/doc.go

@@ -2,7 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package env
+// Package envcmd implements the ``go env'' command.
+package envcmd
 
 import (
 	"fmt"
@@ -103,7 +104,7 @@ func ExtraEnvVars() []cfg.EnvVar {
 }
 
 func runEnv(cmd *base.Command, args []string) {
-	env := cfg.NewEnv
+	env := cfg.CmdEnv
 	env = append(env, ExtraEnvVars()...)
 	if len(args) > 0 {
 		for _, name := range args {

src/cmd/go/internal/env/env.go renamed to src/cmd/go/internal/envcmd/env.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Package fix implements the ``go fix'' command.
 package fix
 
 import (

src/cmd/go/internal/fix/fix.go

@@ -2,7 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package fmt
+// Package fmtcmd implements the ``go fmt'' command.
+package fmtcmd
 
 import (
 	"os"
@@ -15,7 +16,7 @@ import (
 )
 
 func init() {
-	cfg.AddBuildFlagsNX(&CmdFmt.Flag)
+	base.AddBuildFlagsNX(&CmdFmt.Flag)
 }
 
 var CmdFmt = &base.Command{