code review 84650046: go.tools/go/ssa: perform nil check when taking value of...

go/ssa/interp/testdata/boundmeth.go

 // Tests of bound method closures.
 
 package main
 
-import (
-        "errors"
-        "fmt"
-)
+import "fmt"
 
 func assert(b bool) {
         if !b {
                 panic("oops")
         }
 }
 
 type I int
 
 func (i I) add(x int) int {
@@ skipping 80 matching lines @@
 func (err errString) Error() string {
         return string(err)
 }
 
 // Regression test for a builder crash.
 func regress1(x error) func() string {
         return x.Error
 }
 
 // Regression test for b/7269:
-// an interface method value performs a nil check.
-func nilInterface() {
-        err := errors.New("ok")
+// taking the value of an interface method performs a nil check.
+func nilInterfaceMethodValue() {
+        err := fmt.Errorf("ok")
         f := err.Error
         if got := f(); got != "ok" {
                 panic(got)
         }
 
         err = nil
         if got := f(); got != "ok" {
                 panic(got)
         }
 
@@ skipping 14 matching lines @@
         pointerReceiver()
         addressibleValuePointerReceiver()
         promotedReceiver()
         anonStruct()
         typeCheck()
 
         if e := regress1(errString("hi"))(); e != "hi" {
                 panic(e)
         }
 
-        nilInterface()
+        nilInterfaceMethodValue()
 }