From: Russ Cox <rsc@golang.org>
Date: Mon, 13 Mar 2023 17:22:34 +0000 (-0400)
Subject: cmd/go: make go line declare minimum required Go version
X-Git-Tag: go1.21rc1~902
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=4bd20ec884876816e8f011aea931f7b6846c3a4c;p=gostls13.git

cmd/go: make go line declare minimum required Go version

For #57001, enforce the go line as declaring the minimum required
version of Go that can compile a module.

Modules that maintain compatibility with old versions of Go
but want to make use of new features in //go:build-constrained files
will be able to do so: the //go:build constraint will be interpreted
as changing the minimum Go version for that file and will unlock
the Go features allowed in that version.

Change-Id: Ibeeb7c93ce7ea2e5187d78af0757cbfac19484a0
Reviewed-on: https://go-review.googlesource.com/c/go/+/476279
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Russ Cox <rsc@golang.org>
Auto-Submit: Russ Cox <rsc@golang.org>
---

diff --git a/src/cmd/go/internal/work/exec.go b/src/cmd/go/internal/work/exec.go
index c42b9a126e..05734c5e98 100644
--- a/src/cmd/go/internal/work/exec.go
+++ b/src/cmd/go/internal/work/exec.go
@@ -532,6 +532,10 @@ func (b *Builder) build(ctx context.Context, a *Action) (err error) {
 		return errors.New("binary-only packages are no longer supported")
 	}
 
+	if p.Module != nil && !allowedVersion(p.Module.GoVersion) {
+		return errors.New("module requires Go " + p.Module.GoVersion + " or later")
+	}
+
 	if err := b.checkDirectives(a); err != nil {
 		return err
 	}
@@ -853,10 +857,6 @@ OverlayLoop:
 	ofile, out, err := BuildToolchain.gc(b, a, objpkg, icfg.Bytes(), embedcfg, symabis, len(sfiles) > 0, gofiles)
 	if len(out) > 0 {
 		output := b.processOutput(out)
-		if p.Module != nil && !allowedVersion(p.Module.GoVersion) {
-			output += "note: module requires Go " + p.Module.GoVersion + "\n"
-		}
-
 		if err != nil {
 			return formatOutput(b.WorkDir, p.Dir, p.ImportPath, p.Desc(), output)
 		} else {
@@ -864,9 +864,6 @@ OverlayLoop:
 		}
 	}
 	if err != nil {
-		if p.Module != nil && !allowedVersion(p.Module.GoVersion) {
-			b.showOutput(a, p.Dir, p.Desc(), "note: module requires Go "+p.Module.GoVersion+"\n")
-		}
 		return err
 	}
 	if ofile != objpkg {
diff --git a/src/cmd/go/testdata/script/mod_go_version.txt b/src/cmd/go/testdata/script/mod_go_version.txt
index 97d9975e68..005c43ca6e 100644
--- a/src/cmd/go/testdata/script/mod_go_version.txt
+++ b/src/cmd/go/testdata/script/mod_go_version.txt
@@ -3,40 +3,17 @@
 env GO111MODULE=on
 
 go list
-go build
-go build sub.1
-go build subver.1
-! stderr 'module requires'
-! go build badsub.1
-stderr '^note: module requires Go 1.11111$'
-
-go build versioned.1
-go mod edit -require versioned.1@v1.1.0
-! go build versioned.1
-stderr '^note: module requires Go 1.99999$'
-
-[short] stop
-
-# The message should be printed even if the compiler emits no output.
-go build -o $WORK/nooutput.exe nooutput.go
-! go build -toolexec=$WORK/nooutput.exe versioned.1
-stderr '^# versioned.1\nnote: module requires Go 1.99999$'
+! go build sub
+stderr '^sub: module requires Go 1.999 or later$'
 
 -- go.mod --
 module m
-go 1.999
+go 1.1
 require (
-	sub.1 v1.0.0
-	subver.1 v1.0.0
-	badsub.1 v1.0.0
-	versioned.1 v1.0.0
+	sub v1.0.0
 )
 replace (
-	sub.1 => ./sub
-	subver.1 => ./subver
-	badsub.1 => ./badsub
-	versioned.1 v1.0.0 => ./versioned1
-	versioned.1 v1.1.0 => ./versioned2
+	sub => ./sub
 )
 
 -- x.go --
@@ -44,67 +21,7 @@ package x
 
 -- sub/go.mod --
 module m
-go 1.11
+go 1.999
 
 -- sub/x.go --
 package x
-
--- subver/go.mod --
-module m
-go 1.11111
-
--- subver/x.go --
-package x
-
--- badsub/go.mod --
-module m
-go 1.11111
-
--- badsub/x.go --
-package x
-invalid syntax
-
--- versioned1/go.mod --
-module versioned
-go 1.0
-
--- versioned1/x.go --
-package x
-
--- versioned2/go.mod --
-module versioned
-go 1.99999
-
--- versioned2/x.go --
-package x
-invalid syntax
-
--- nooutput.go --
-// +build ignore
-
-package main
-
-import (
-	"bytes"
-	"os"
-	"os/exec"
-	"strings"
-)
-
-func main() {
-	stderr := new(bytes.Buffer)
-	stdout := new(bytes.Buffer)
-
-	cmd := exec.Command(os.Args[1], os.Args[2:]...)
-	cmd.Stderr = stderr
-	cmd.Stdout = stdout
-
-	err := cmd.Run()
-	if strings.HasPrefix(os.Args[2], "-V") {
-		os.Stderr.Write(stderr.Bytes())
-		os.Stdout.Write(stdout.Bytes())
-	}
-	if err != nil {
-		os.Exit(1)
-	}
-}