cmd/doc: provide working directory to build.Import calls
The current cmd/doc implementation uses go/build.Import in a few
places to check whether a package is findable and importable.
go/build has limited support for finding packages in modules,
but to do so, build.Import requires knowing the source directory
to use when performing the lookup (so it can find the go.mod file).
Otherwise, it only looks inside the GOPATH workspace.
Start passing the current working directory to build.Import calls,
so that it can correctly look for packages in modules when in cmd/doc
is executed in module mode.
Before this change, cmd/doc in module mode could mistakenly find and
use a package in the GOPATH workspace, instead of the current module.
Since the result of os.Getwd is needed in even more places, assign it
to a local variable in parseArgs now.
Fixes #28992
Updates #26504
Change-Id: I7571618e18420d2d3b3890cc69ade2d97b1962bf
Reviewed-on: https://go-review.googlesource.com/c/go/+/183991
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
diff --git a/src/cmd/doc/doc_test.go b/src/cmd/doc/doc_test.go
index bc870ac..11d0bda 100644
--- a/src/cmd/doc/doc_test.go
+++ b/src/cmd/doc/doc_test.go
@@ -920,7 +920,10 @@
t.Skip("scanning file system takes too long")
}
maybeSkip(t)
- where := pwd()
+ where, err := os.Getwd()
+ if err != nil {
+ t.Fatal(err)
+ }
defer func() {
if err := os.Chdir(where); err != nil {
t.Fatal(err)
@@ -931,7 +934,7 @@
}
var b bytes.Buffer
var flagSet flag.FlagSet
- err := do(&b, &flagSet, []string{"./template"})
+ err = do(&b, &flagSet, []string{"./template"})
if err != nil {
t.Errorf("unexpected error %q from ./template", err)
}
diff --git a/src/cmd/doc/main.go b/src/cmd/doc/main.go
index 9e3ad0c..a739761 100644
--- a/src/cmd/doc/main.go
+++ b/src/cmd/doc/main.go
@@ -187,16 +187,20 @@
// is rand.Float64, we must scan both crypto/rand and math/rand
// to find the symbol, and the first call will return crypto/rand, true.
func parseArgs(args []string) (pkg *build.Package, path, symbol string, more bool) {
+ wd, err := os.Getwd()
+ if err != nil {
+ log.Fatal(err)
+ }
if len(args) == 0 {
// Easy: current directory.
- return importDir(pwd()), "", "", false
+ return importDir(wd), "", "", false
}
arg := args[0]
// We have an argument. If it is a directory name beginning with . or ..,
// use the absolute path name. This discriminates "./errors" from "errors"
// if the current directory contains a non-standard errors package.
if isDotSlash(arg) {
- arg = filepath.Join(pwd(), arg)
+ arg = filepath.Join(wd, arg)
}
switch len(args) {
default:
@@ -205,7 +209,7 @@
// Done below.
case 2:
// Package must be findable and importable.
- pkg, err := build.Import(args[0], "", build.ImportComment)
+ pkg, err := build.Import(args[0], wd, build.ImportComment)
if err == nil {
return pkg, args[0], args[1], false
}
@@ -225,7 +229,7 @@
// First, is it a complete package path as it is? If so, we are done.
// This avoids confusion over package paths that have other
// package paths as their prefix.
- pkg, err := build.Import(arg, "", build.ImportComment)
+ pkg, err = build.Import(arg, wd, build.ImportComment)
if err == nil {
return pkg, arg, "", false
}
@@ -260,7 +264,7 @@
symbol = arg[period+1:]
}
// Have we identified a package already?
- pkg, err := build.Import(arg[0:period], "", build.ImportComment)
+ pkg, err := build.Import(arg[0:period], wd, build.ImportComment)
if err == nil {
return pkg, arg[0:period], symbol, false
}
@@ -283,7 +287,7 @@
log.Fatalf("no such package %s", arg[0:period])
}
// Guess it's a symbol in the current directory.
- return importDir(pwd()), "", arg, false
+ return importDir(wd), "", arg, false
}
// dotPaths lists all the dotted paths legal on Unix-like and
@@ -385,12 +389,3 @@
func splitGopath() []string {
return filepath.SplitList(buildCtx.GOPATH)
}
-
-// pwd returns the current directory.
-func pwd() string {
- wd, err := os.Getwd()
- if err != nil {
- log.Fatal(err)
- }
- return wd
-}
diff --git a/src/cmd/go/testdata/script/mod_doc.txt b/src/cmd/go/testdata/script/mod_doc.txt
index 40acbc5..d7aa553 100644
--- a/src/cmd/go/testdata/script/mod_doc.txt
+++ b/src/cmd/go/testdata/script/mod_doc.txt
@@ -3,6 +3,7 @@
env GO111MODULE=on
[short] skip
+# Check when module x is inside GOPATH/src.
go doc y
stdout 'Package y is.*alphabet'
stdout 'import "x/y"'
@@ -16,13 +17,25 @@
go doc quote
stdout 'Package quote collects pithy sayings.'
-# Double-check go doc y when y is not in GOPATH/src.
-env GOPATH=$WORK/altgopath
+# Double-check when module x is outside GOPATH/src.
+env GOPATH=$WORK/emptygopath
go doc x/y
stdout 'Package y is.*alphabet'
go doc y
stdout 'Package y is.*alphabet'
+# Triple-check when module x is outside GOPATH/src,
+# but other packages with same import paths are in GOPATH/src.
+# Since go doc is running in module mode here, packages in active module
+# should be preferred over packages in GOPATH. See golang.org/issue/28992.
+env GOPATH=$WORK/gopath2
+go doc x/y
+! stdout 'Package y is.*GOPATH'
+stdout 'Package y is.*alphabet'
+go doc rsc.io/quote
+! stdout 'Package quote is located in a GOPATH workspace.'
+stdout 'Package quote collects pithy sayings.'
+
-- go.mod --
module x
require rsc.io/quote v1.5.2
@@ -33,3 +46,13 @@
-- x.go --
package x
+
+-- $WORK/gopath2/src/x/y/y.go --
+// Package y is located in a GOPATH workspace.
+package y
+-- $WORK/gopath2/src/rsc.io/quote/quote.go --
+// Package quote is located in a GOPATH workspace.
+package quote
+
+// Hello is located in a GOPATH workspace.
+func Hello() string { return "" }
