cmd/go: split out cmd/go/internal/work

This is one CL in a long sequence of changes to break up the
go command from one package into a plausible group of packages.

This sequence is concerned only with moving code, not changing
or cleaning up code. There will still be more cleanup after this sequence.

The entire sequence will be submitted together: it is not a goal
for the tree to build at every step.

For #18653.

Change-Id: Icdd181098f9f0e81f68bf201e6867cdd8f820300
Reviewed-on: https://go-review.googlesource.com/36197
Reviewed-by: David Crawshaw <[email protected]>

src/cmd/go/clean.go

@@ -5,14 +5,16 @@
 package main
 
 import (
-	"cmd/go/internal/base"
-	"cmd/go/internal/cfg"
-	"cmd/go/internal/load"
 	"fmt"
 	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/work"
 )
 
 var cmdClean = &base.Command{
@@ -74,7 +76,7 @@ func init() {
 	// mentioned explicitly in the docs but they
 	// are part of the build flags.
 
-	addBuildFlags(cmdClean)
+	work.AddBuildFlags(cmdClean)
 }
 
 func runClean(cmd *base.Command, args []string) {
@@ -124,8 +126,8 @@ func clean(p *load.Package) {
 		return
 	}
 
-	var b builder
-	b.print = fmt.Print
+	var b work.Builder
+	b.Print = fmt.Print
 
 	packageFile := map[string]bool{}
 	if p.Name != "main" {
@@ -176,7 +178,7 @@ func clean(p *load.Package) {
 	}
 
 	if cfg.BuildN || cfg.BuildX {
-		b.showcmd(p.Dir, "rm -f %s", strings.Join(allRemove, " "))
+		b.Showcmd(p.Dir, "rm -f %s", strings.Join(allRemove, " "))
 	}
 
 	toRemove := map[string]bool{}
@@ -189,7 +191,7 @@ func clean(p *load.Package) {
 			// TODO: Remove once Makefiles are forgotten.
 			if cleanDir[name] {
 				if cfg.BuildN || cfg.BuildX {
-					b.showcmd(p.Dir, "rm -r %s", name)
+					b.Showcmd(p.Dir, "rm -r %s", name)
 					if cfg.BuildN {
 						continue
 					}
@@ -212,7 +214,7 @@ func clean(p *load.Package) {
 
 	if cleanI && p.Internal.Target != "" {
 		if cfg.BuildN || cfg.BuildX {
-			b.showcmd("", "rm -f %s", p.Internal.Target)
+			b.Showcmd("", "rm -f %s", p.Internal.Target)
 		}
 		if !cfg.BuildN {
 			removeFile(p.Internal.Target)

src/cmd/go/env.go

@@ -5,13 +5,15 @@
 package main
 
 import (
-	"cmd/go/internal/base"
-	"cmd/go/internal/cfg"
-	"cmd/go/internal/load"
 	"fmt"
 	"os"
 	"runtime"
 	"strings"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/work"
 )
 
 var cmdEnv = &base.Command{
@@ -29,8 +31,8 @@ each named variable on its own line.
 }
 
 func mkEnv() []cfg.EnvVar {
-	var b builder
-	b.init()
+	var b work.Builder
+	b.Init()
 
 	env := []cfg.EnvVar{
 		{"GOARCH", cfg.Goarch},
@@ -48,10 +50,10 @@ func mkEnv() []cfg.EnvVar {
 		{"TERM", "dumb"},
 	}
 
-	if gccgoBin != "" {
-		env = append(env, cfg.EnvVar{"GCCGO", gccgoBin})
+	if work.GccgoBin != "" {
+		env = append(env, cfg.EnvVar{"GCCGO", work.GccgoBin})
 	} else {
-		env = append(env, cfg.EnvVar{"GCCGO", gccgoName})
+		env = append(env, cfg.EnvVar{"GCCGO", work.GccgoName})
 	}
 
 	switch cfg.Goarch {
@@ -61,10 +63,10 @@ func mkEnv() []cfg.EnvVar {
 		env = append(env, cfg.EnvVar{"GO386", os.Getenv("GO386")})
 	}
 
-	cmd := b.gccCmd(".")
+	cmd := b.GccCmd(".")
 	env = append(env, cfg.EnvVar{"CC", cmd[0]})
 	env = append(env, cfg.EnvVar{"GOGCCFLAGS", strings.Join(cmd[3:], " ")})
-	cmd = b.gxxCmd(".")
+	cmd = b.GxxCmd(".")
 	env = append(env, cfg.EnvVar{"CXX", cmd[0]})
 
 	if cfg.BuildContext.CgoEnabled {
@@ -87,11 +89,11 @@ func findEnv(env []cfg.EnvVar, name string) string {
 
 // extraEnvVars returns environment variables that should not leak into child processes.
 func extraEnvVars() []cfg.EnvVar {
-	var b builder
-	b.init()
-	cppflags, cflags, cxxflags, fflags, ldflags := b.cflags(&load.Package{})
+	var b work.Builder
+	b.Init()
+	cppflags, cflags, cxxflags, fflags, ldflags := b.CFlags(&load.Package{})
 	return []cfg.EnvVar{
-		{"PKG_CONFIG", b.pkgconfigCmd()},
+		{"PKG_CONFIG", b.PkgconfigCmd()},
 		{"CGO_CFLAGS", strings.Join(cflags, " ")},
 		{"CGO_CPPFLAGS", strings.Join(cppflags, " ")},
 		{"CGO_CXXFLAGS", strings.Join(cxxflags, " ")},

src/cmd/go/generate.go

@@ -10,6 +10,7 @@ import (
 	"cmd/go/internal/base"
 	"cmd/go/internal/cfg"
 	"cmd/go/internal/load"
+	"cmd/go/internal/work"
 	"fmt"
 	"io"
 	"log"
@@ -134,7 +135,7 @@ var (
 )
 
 func init() {
-	addBuildFlags(cmdGenerate)
+	work.AddBuildFlags(cmdGenerate)
 	cmdGenerate.Flag.StringVar(&generateRunFlag, "run", "", "")
 }
 

src/cmd/go/get.go

@@ -9,6 +9,7 @@ import (
 	"cmd/go/internal/cfg"
 	"cmd/go/internal/load"
 	"cmd/go/internal/str"
+	"cmd/go/internal/work"
 	"fmt"
 	"go/build"
 	"os"
@@ -83,7 +84,7 @@ var getFix = cmdGet.Flag.Bool("fix", false, "")
 var getInsecure = cmdGet.Flag.Bool("insecure", false, "")
 
 func init() {
-	addBuildFlags(cmdGet)
+	work.AddBuildFlags(cmdGet)
 	cmdGet.Run = runGet // break init loop
 }
 
@@ -157,7 +158,7 @@ func runGet(cmd *base.Command, args []string) {
 		return
 	}
 
-	installPackages(args, true)
+	work.InstallPackages(args, true)
 }
 
 // downloadPaths prepares the list of paths to pass to download.

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

@@ -0,0 +1,37 @@
+// Copyright 2017 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 base
+
+import "strings"
+
+// envForDir returns a copy of the environment
+// suitable for running in the given directory.
+// The environment is the current process's environment
+// but with an updated $PWD, so that an os.Getwd in the
+// child will be faster.
+func EnvForDir(dir string, base []string) []string {
+	// Internally we only use rooted paths, so dir is rooted.
+	// Even if dir is not rooted, no harm done.
+	return MergeEnvLists([]string{"PWD=" + dir}, base)
+}
+
+// MergeEnvLists merges the two environment lists such that
+// variables with the same name in "in" replace those in "out".
+// This always returns a newly allocated slice.
+func MergeEnvLists(in, out []string) []string {
+	out = append([]string(nil), out...)
+NextVar:
+	for _, inkv := range in {
+		k := strings.SplitAfterN(inkv, "=", 2)[0]
+		for i, outkv := range out {
+			if strings.HasPrefix(outkv, k) {
+				out[i] = inkv
+				continue NextVar
+			}
+		}
+		out = append(out, inkv)
+	}
+	return out
+}

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

@@ -0,0 +1,33 @@
+// Copyright 2017 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 base
+
+import (
+	"cmd/go/internal/str"
+	"flag"
+)
+
+// A StringsFlag is a command-line flag that interprets its argument
+// as a space-separated list of possibly-quoted strings.
+type StringsFlag []string
+
+func (v *StringsFlag) Set(s string) error {
+	var err error
+	*v, err = str.SplitQuotedFields(s)
+	if *v == nil {
+		*v = []string{}
+	}
+	return err
+}
+
+func (v *StringsFlag) String() string {
+	return "<StringsFlag>"
+}
+
+// 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, "")
+}

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

@@ -7,6 +7,7 @@ package base
 import (
 	"os"
 	"path/filepath"
+	"strings"
 )
 
 var Cwd, _ = os.Getwd()
@@ -34,3 +35,10 @@ func RelPaths(paths []string) []string {
 	}
 	return out
 }
+
+// IsTestFile reports whether the source file is a set of tests and should therefore
+// be excluded from coverage analysis.
+func IsTestFile(file string) bool {
+	// We don't cover tests, only the code they test.
+	return strings.HasSuffix(file, "_test.go")
+}

src/cmd/go/internal/str/str.go

@@ -95,3 +95,47 @@ func Contains(x []string, s string) bool {
 	}
 	return false
 }
+
+func isSpaceByte(c byte) bool {
+	return c == ' ' || c == '\t' || c == '\n' || c == '\r'
+}
+
+// SplitQuotedFields splits s into a list of fields,
+// allowing single or double quotes around elements.
+// There is no unescaping or other processing within
+// quoted fields.
+func SplitQuotedFields(s string) ([]string, error) {
+	// Split fields allowing '' or "" around elements.
+	// Quotes further inside the string do not count.
+	var f []string
+	for len(s) > 0 {
+		for len(s) > 0 && isSpaceByte(s[0]) {
+			s = s[1:]
+		}
+		if len(s) == 0 {
+			break
+		}
+		// Accepted quoted string. No unescaping inside.
+		if s[0] == '"' || s[0] == '\'' {
+			quote := s[0]
+			s = s[1:]
+			i := 0
+			for i < len(s) && s[i] != quote {
+				i++
+			}
+			if i >= len(s) {
+				return nil, fmt.Errorf("unterminated %c string", quote)
+			}
+			f = append(f, s[:i])
+			s = s[i+1:]
+			continue
+		}
+		i := 0
+		for i < len(s) && !isSpaceByte(s[i]) {
+			i++
+		}
+		f = append(f, s[:i])
+		s = s[i:]
+	}
+	return f, nil
+}