commit 5831d16d18029819d39f99bdc2060b8eff410b6b
author Dmitri Shuralyov <shurcooL@gmail.com> Mon May 22 16:11:25 2017 -0400
committer Alan Donovan <adonovan@google.com> Tue Aug 08 14:46:45 2017 +0000
tree 0f70540069ef7d644ed37eeec47b76ae44462d51
parent f03b3350b7d6cb09e4221e7f2ecffaf41f89fce1

cmd/callgraph: fix "import path of the enclosing package" example in usage

Caller is *ssa.Function. Its Pkg field is *ssa.Package. But ssa.Package
struct doesn't contain either field or method named Object.

So one gets the following error:

	$ callgraph -format '{{.Caller.Pkg.Object.Path}} -> {{.Callee.Pkg.Object.Path}}' \
	    $(go env GOROOT)/src/net/http/triv.go | sort | uniq
	callgraph: template: -format:1:9: executing "-format" at <.Caller.Pkg.Object.P...>: can't evaluate field Object in type *ssa.Package

ssa.Package contains Pkg field:

	Pkg     *types.Package    // the corresponding go/types.Package

types.Package contains Path() method that returns the package path.

That appears to be the right way to get the "import path of the
enclosing package" with the current x/tools/go/ssa API.

Fixes golang/go#20459.

Change-Id: I3cb7b61b767148f5c771d57f8f5e7e6ab20aea87
Reviewed-on: https://go-review.googlesource.com/43812
Reviewed-by: Avelino <t@avelino.xxx>
Reviewed-by: Alan Donovan <adonovan@google.com>

cmd/callgraph/main.go

diff --git a/cmd/callgraph/main.go b/cmd/callgraph/main.go
index bff39c2..8ef4597 100644
--- a/cmd/callgraph/main.go
+++ b/cmd/callgraph/main.go
@@ -114,7 +114,7 @@
 
            Caller and Callee are *ssa.Function values, which print as
            "(*sync/atomic.Mutex).Lock", but other attributes may be
-           derived from them, e.g. Caller.Pkg.Object.Path yields the
+           derived from them, e.g. Caller.Pkg.Pkg.Path yields the
            import path of the enclosing package.  Consult the go/ssa
            API documentation for details.
 
@@ -128,7 +128,7 @@
 
   Same, but show only the packages of each function:
 
-    callgraph -format '{{.Caller.Pkg.Object.Path}} -> {{.Callee.Pkg.Object.Path}}' \
+    callgraph -format '{{.Caller.Pkg.Pkg.Path}} -> {{.Callee.Pkg.Pkg.Path}}' \
       $GOROOT/src/net/http/triv.go | sort | uniq
 
   Show functions that make dynamic calls into the 'fmt' test package,