go/packages: add a Module field to the Package struct

This change introduces Module and ModuleError struct types to the
packages package with the same types as defined in the cmd/go
documentation for module information output by go list (with the
exception of the Module type's Versions and Update fields).
go/packages will fill the module struct with the module information
output by go list. Drivers that support modules can also provide
module information by filling the Module fields in the packages in
their driverResponses.

Fixes golang/go#35921

Change-Id: Icbdf79869f09d26f6a01c3670146ace4f6ffa25e
Reviewed-on: https://go-review.googlesource.com/c/tools/+/234219
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>

1 files changed, 27 insertions, 4 deletions

diff --git a/go/packages/packages.go b/go/packages/packages.go
index 68039d3a9..1e6f9a467 100644
--- a/go/packages/packages.go
+++ b/go/packages/packages.go
@@ -22,6 +22,7 @@ import (
 	"reflect"
 	"strings"
 	"sync"
+	"time"
 
 	"golang.org/x/tools/go/gcexportdata"
 	"golang.org/x/tools/internal/gocommand"
@@ -75,6 +76,9 @@ const (
 	// TypecheckCgo enables full support for type checking cgo. Requires Go 1.15+.
 	// Modifies CompiledGoFiles and Types, and has no effect on its own.
 	TypecheckCgo
+
+	// NeedModule adds Module.
+	NeedModule
 )
 
 const (
@@ -310,16 +314,32 @@ type Package struct {
 	forTest string
 
 	// module is the module information for the package if it exists.
-	module *packagesinternal.Module
+	Module *Module
+}
+
+// Module provides module information for a package.
+type Module struct {
+	Path      string       // module path
+	Version   string       // module version
+	Replace   *Module      // replaced by this module
+	Time      *time.Time   // time version was created
+	Main      bool         // is this the main module?
+	Indirect  bool         // is this module only an indirect dependency of main module?
+	Dir       string       // directory holding files for this module, if any
+	GoMod     string       // path to go.mod file used when loading this module, if any
+	GoVersion string       // go version used in module
+	Error     *ModuleError // error loading module
+}
+
+// ModuleError holds errors loading a module.
+type ModuleError struct {
+	Err string // the error itself
 }
 
 func init() {
 	packagesinternal.GetForTest = func(p interface{}) string {
 		return p.(*Package).forTest
 	}
-	packagesinternal.GetModule = func(p interface{}) *packagesinternal.Module {
-		return p.(*Package).module
-	}
 	packagesinternal.GetGoCmdRunner = func(config interface{}) *gocommand.Runner {
 		return config.(*Config).gocmdRunner
 	}
@@ -708,6 +728,9 @@ func (ld *loader) refine(roots []string, list ...*Package) ([]*Package, error) {
 		if ld.requestedMode&NeedTypesSizes == 0 {
 			ld.pkgs[i].TypesSizes = nil
 		}
+		if ld.requestedMode&NeedModule == 0 {
+			ld.pkgs[i].Module = nil
+		}
 	}
 
 	return result, nil