[dev.cmdgo] cmd/go: maintain a go.work.sum file

This change causes the go command to maintain a separate go.work.sum
file when in workspace mode rather than using the go.sum files
from the individual modules. This isn't quite what the proposal
spec specifies, which is that the sums that don't exist in any
of the workspace modules are added to go.work.sum rather than
the necessary sums. That will be done in a future change.

Change-Id: I528b9b153a93a4cd67c5af471ad6d5bd3628578b
Reviewed-on: https://go-review.googlesource.com/c/go/+/334939
Trust: Michael Matloob <matloob@golang.org>
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

1 files changed, 42 insertions, 4 deletions

diff --git a/src/cmd/go/testdata/script/work.txt b/src/cmd/go/testdata/script/work.txt
index c68ca89a76..0d820fffc2 100644
--- a/src/cmd/go/testdata/script/work.txt
+++ b/src/cmd/go/testdata/script/work.txt
@@ -1,13 +1,20 @@
 go mod initwork ./a ./b
 cmp go.work go.work.want
 
+! go run  example.com/b
+stderr 'a(\\|/)a.go:4:8: no required module provides package rsc.io/quote; to add it:\n\tgo get rsc.io/quote'
+cd a
+go get rsc.io/quote
+go env GOMOD # go env GOMOD reports the module in a single module context
+stdout $GOPATH(\\|/)src(\\|/)a(\\|/)go.mod
+cd ..
 go run example.com/b
-stdout 'Hello from module A'
+stdout 'Hello, world.'
 
 # And try from a different directory
 cd c
-go run example.com/b
-stdout 'Hello from module A'
+go run  example.com/b
+stdout 'Hello, world.'
 cd $GOPATH/src
 
 go list all # all includes both modules
@@ -26,6 +33,9 @@ cp go.work.dup go.work
 stderr 'reading go.work: path .* appears multiple times in workspace'
 cp go.work.backup go.work
 
+cp go.work.d go.work
+go run example.com/d
+
 -- go.work.dup --
 go 1.17
 
@@ -41,6 +51,14 @@ directory (
 	./a
 	./b
 )
+-- go.work.d --
+go 1.17
+
+directory (
+	a
+	b
+	d
+)
 -- a/go.mod --
 
 module example.com/a
@@ -49,9 +67,10 @@ module example.com/a
 package a
 
 import "fmt"
+import "rsc.io/quote"
 
 func HelloFromA() {
-  fmt.Println("Hello from module A")
+  fmt.Println(quote.Hello())
 }
 
 -- b/go.mod --
@@ -66,8 +85,27 @@ import "example.com/a"
 func main() {
   a.HelloFromA()
 }
+-- b/lib/hello.go --
+package lib
+
+import "example.com/a"
+
+func Hello() {
+	a.HelloFromA()
+}
 
 -- c/README --
 Create this directory so we can cd to
 it and make sure paths are interpreted
 relative to the go.work, not the cwd.
+-- d/go.mod --
+module example.com/d
+
+-- d/main.go --
+package main
+
+import "example.com/b/lib"
+
+func main() {
+	lib.Hello()
+}