cmd/doc: show original import error when package cannot be found
Updates #34669
Change-Id: I8d0ee68885e804e131f42a512080486f9b25e9dd
Reviewed-on: https://go-review.googlesource.com/c/go/+/199819
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
diff --git a/src/cmd/doc/main.go b/src/cmd/doc/main.go
index dd15e80..0f817b6 100644
--- a/src/cmd/doc/main.go
+++ b/src/cmd/doc/main.go
@@ -231,8 +231,8 @@
// 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, wd, build.ImportComment)
- if err == nil {
+ pkg, importErr := build.Import(arg, wd, build.ImportComment)
+ if importErr == nil {
return pkg, arg, "", false
}
// Another disambiguator: If the symbol starts with an upper
@@ -286,7 +286,18 @@
}
// If it has a slash, we've failed.
if slash >= 0 {
- log.Fatalf("no such package %s", arg[0:period])
+ // build.Import should always include the path in its error message,
+ // and we should avoid repeating it. Unfortunately, build.Import doesn't
+ // return a structured error. That can't easily be fixed, since it
+ // invokes 'go list' and returns the error text from the loaded package.
+ // TODO(golang.org/issue/34750): load using golang.org/x/tools/go/packages
+ // instead of go/build.
+ importErrStr := importErr.Error()
+ if strings.Contains(importErrStr, arg[:period]) {
+ log.Fatal(importErrStr)
+ } else {
+ log.Fatalf("no such package %s: %s", arg[:period], importErrStr)
+ }
}
// Guess it's a symbol in the current directory.
return importDir(wd), "", arg, false
diff --git a/src/cmd/go/testdata/script/mod_doc.txt b/src/cmd/go/testdata/script/mod_doc.txt
index d7aa553..047e9f4 100644
--- a/src/cmd/go/testdata/script/mod_doc.txt
+++ b/src/cmd/go/testdata/script/mod_doc.txt
@@ -36,6 +36,11 @@
! stdout 'Package quote is located in a GOPATH workspace.'
stdout 'Package quote collects pithy sayings.'
+# Check that a sensible error message is printed when a package is not found.
+env GOPROXY=off
+! go doc example.com/hello
+stderr '^doc: cannot find module providing package example.com/hello: module lookup disabled by GOPROXY=off$'
+
-- go.mod --
module x
require rsc.io/quote v1.5.2
