From: Bryan C. Mills <bcmills@google.com>
Date: Fri, 20 Nov 2020 22:03:42 +0000 (-0500)
Subject: cmd/go/internal/modload: remove the Reqs function
X-Git-Tag: go1.16beta1~176
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=f93ef07b1143abf3003555c4afcadc0e9842cbf8;p=gostls13.git

cmd/go/internal/modload: remove the Reqs function

The Reqs function returns an mvs.Reqs implemention for the global
build list. The API that it presents assumes that the build list is
globally consistent (problematic for #40775) and readily available
(problematic for #36460).

Fortunately, it is no longer used outside of the modload package.
We can instead use individual instances of the unexported mvsReqs
struct, making the dependency on the global build list more explicit.

For #36460
For #40775

Change-Id: I8674442f2a86416b0bf9c3395cb591c1e724c9d2
Reviewed-on: https://go-review.googlesource.com/c/go/+/272129
Trust: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>
---

diff --git a/src/cmd/go/internal/modload/init.go b/src/cmd/go/internal/modload/init.go
index b9345acbce..a9b77c82b3 100644
--- a/src/cmd/go/internal/modload/init.go
+++ b/src/cmd/go/internal/modload/init.go
@@ -853,7 +853,7 @@ func MinReqs() mvs.Reqs {
 			retain = append(retain, m.Path)
 		}
 	}
-	min, err := mvs.Req(Target, retain, Reqs())
+	min, err := mvs.Req(Target, retain, &mvsReqs{buildList: buildList})
 	if err != nil {
 		base.Fatalf("go: %v", err)
 	}
@@ -985,7 +985,7 @@ func keepSums(addDirect bool) map[module.Version]bool {
 	keep := make(map[module.Version]bool)
 	var mu sync.Mutex
 	reqs := &keepSumReqs{
-		Reqs: Reqs(),
+		Reqs: &mvsReqs{buildList: buildList},
 		visit: func(m module.Version) {
 			// If we build using a replacement module, keep the sum for the replacement,
 			// since that's the code we'll actually use during a build.
diff --git a/src/cmd/go/internal/modload/load.go b/src/cmd/go/internal/modload/load.go
index 302330278e..732c4af92b 100644
--- a/src/cmd/go/internal/modload/load.go
+++ b/src/cmd/go/internal/modload/load.go
@@ -800,7 +800,7 @@ func loadFromRoots(params loaderParams) *loader {
 	}
 
 	var err error
-	reqs := Reqs()
+	reqs := &mvsReqs{buildList: buildList}
 	buildList, err = mvs.BuildList(Target, reqs)
 	if err != nil {
 		base.Fatalf("go: %v", err)
@@ -842,7 +842,7 @@ func loadFromRoots(params loaderParams) *loader {
 		}
 
 		// Recompute buildList with all our additions.
-		reqs = Reqs()
+		reqs = &mvsReqs{buildList: buildList}
 		buildList, err = mvs.BuildList(Target, reqs)
 		if err != nil {
 			// If an error was found in a newly added module, report the package
diff --git a/src/cmd/go/internal/modload/mvs.go b/src/cmd/go/internal/modload/mvs.go
index db57b3ec5f..167d6819b0 100644
--- a/src/cmd/go/internal/modload/mvs.go
+++ b/src/cmd/go/internal/modload/mvs.go
@@ -11,7 +11,6 @@ import (
 	"sort"
 
 	"cmd/go/internal/modfetch"
-	"cmd/go/internal/mvs"
 
 	"golang.org/x/mod/module"
 	"golang.org/x/mod/semver"
@@ -23,16 +22,6 @@ type mvsReqs struct {
 	buildList []module.Version
 }
 
-// Reqs returns the current module requirement graph.
-// Future calls to EditBuildList do not affect the operation
-// of the returned Reqs.
-func Reqs() mvs.Reqs {
-	r := &mvsReqs{
-		buildList: buildList,
-	}
-	return r
-}
-
 func (r *mvsReqs) Required(mod module.Version) ([]module.Version, error) {
 	if mod == Target {
 		// Use the build list as it existed when r was constructed, not the current
diff --git a/src/cmd/go/internal/modload/mvs_test.go b/src/cmd/go/internal/modload/mvs_test.go
index 0cb376ec3c..50e93c381f 100644
--- a/src/cmd/go/internal/modload/mvs_test.go
+++ b/src/cmd/go/internal/modload/mvs_test.go
@@ -2,19 +2,17 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package modload_test
+package modload
 
 import (
 	"testing"
-
-	"cmd/go/internal/modload"
 )
 
 func TestReqsMax(t *testing.T) {
 	type testCase struct {
 		a, b, want string
 	}
-	reqs := modload.Reqs()
+	reqs := new(mvsReqs)
 	for _, tc := range []testCase{
 		{a: "v0.1.0", b: "v0.2.0", want: "v0.2.0"},
 		{a: "v0.2.0", b: "v0.1.0", want: "v0.2.0"},
@@ -27,7 +25,7 @@ func TestReqsMax(t *testing.T) {
 	} {
 		max := reqs.Max(tc.a, tc.b)
 		if max != tc.want {
-			t.Errorf("Reqs().Max(%q, %q) = %q; want %q", tc.a, tc.b, max, tc.want)
+			t.Errorf("(%T).Max(%q, %q) = %q; want %q", reqs, tc.a, tc.b, max, tc.want)
 		}
 	}
 }