It looks the specified import path doesn't work when modules feature is enabled.

/cc @robpike

I'll be able to look into this issue.

Actually, I can't reproduce this with Go 1.12.1 nor Go tip (at commit fd270d8):

$ cd $(mktemp -d)
$ go mod init m
go: creating new go.mod: module m
$ go get rsc.io/quote/v3
$ go doc rsc.io/quote/v3
package quote // import "rsc.io/quote/v3"

Package quote collects pithy sayings.

func Concurrency() string
func GlassV3() string
func GoV3() string
func HelloV3() string
func OptV3() string

@rsc What version of Go did you use? Where were the commands you ran before to initialize the main module?

There's a chance this is the same issue as #28992 (comment).

Timed out in state WaitingForInfo. Closing.

(I am just a bot, though. Please speak up if this is a mistake or you have the requested information.)

@rsc is this still an issue? Do you have updated repro steps? Thanks.

@dmitshur

$ go doc rsc.io/quote/v3
package quote // import "rsc.io/quote"

Package quote collects pithy sayings.

func HelloV3() string

I ran this on go version go1.12.6 linux/amd64 in a local module aftering go get rsc.io/quote/v3

@mseshachalam Did you have a copy of rsc.io/quote repository in your GOPATH/src?

Can you check if commit 3b040b7 fixes it?

@dmitshur I have a copy of `rsc.io/quote' at $GOPATH/src/rsc.io/quote pointing master branch at rsc/quote@5d9f230
I had to correct a syntax error at v3/quote.go

git diff v3/quote.go
diff --git a/v3/quote.go b/v3/quote.go
index 1f5f3d6..9b6071f 100644
--- a/v3/quote.go
+++ b/v3/quote.go
@@ -10,3 +10,4 @@ import "rsc.io/sampler"
 // Hello returns a greeting.
 func HelloV3() string {
        return sampler.Hello()
+}

I tested this with go 1.12.7 and observed the same behavior. Does this version of go include 3b040b7?

Go 1.12.7 does not include it, it's currently only available on the latest master branch. You can use golang.org/dl/gotip to try it.

Yeah. gotip works as expected.

seshachalamm@IMCHLT047:~/hello$ gotip doc rsc.io/quote/v3
package quote // import "rsc.io/quote/v3"

Package quote collects pithy sayings.

func Concurrency() string
func GlassV3() string
func GoV3() string
func HelloV3() string
func OptV3() string

seshachalamm@IMCHLT047:~/hello$ go doc rsc.io/quote/v3
package quote // import "rsc.io/quote"

Package quote collects pithy sayings.

func HelloV3() string

Could you please explain briefly about the changes in gotip and go 1.12.7 ?
The output is significantly different. I imagine gotip is using the tags of a library and go1.12.6 is using master branch ?

Thanks for confirming @mseshachalam.

The change was CL 183991, you can read its commit message for details. It fixed issue #28992, which was that in some conditions, go doc was incorrectly using packages in your GOPATH workspace instead of from the appropriate module.

I imagine gotip is using the tags of a library and go1.12.6 is using master branch ?

Yes, it's now using the rsc.io/quote/v3 module (at some version as determined by your main module), instead of the v3 subdirectory of rsc.io/quote repository in your GOPATH workspace (on master branch).