Update toolexec-test

 * main: toolexec rewrite expected
 * p1: no import, no rewrite
 * p2: already wrapped
 * p3: toolexec rewrite expected

cmd/errtrace/testdata/toolexec-test/p1/p1.go

@@ -8,5 +8,5 @@ import (
 
 // WrapP2 wraps an error return from p2.
 func WrapP2() error {
-	return fmt.Errorf("test2: %w", p2.ReturnErr())
+	return fmt.Errorf("test2: %w", p2.CallP3())
 }

cmd/errtrace/testdata/toolexec-test/p2/p2.go

@@ -1,12 +1,12 @@
 package p2
 
 import (
-	"errors"
-
 	"braces.dev/errtrace"
+
+	"braces.dev/errtrace/cmd/errtrace/testdata/toolexec-test/p3"
 )
 
-// ReturnErr returns an error.
-func ReturnErr() error {
-	return errtrace.Wrap(errors.New("test")) // @trace
+// CallP3 calls p3, and wraps the error.
+func CallP3() error {
+	return errtrace.Wrap(p3.ReturnErr()) // @trace
 }

cmd/errtrace/testdata/toolexec-test/p2/errtrace.go → cmd/errtrace/testdata/toolexec-test/p3/errtrace.go

@@ -1,4 +1,4 @@
-package p2
+package p3
 
 // Opt-in to errtrace wrapping with toolexec.
 import _ "braces.dev/errtrace"

cmd/errtrace/testdata/toolexec-test/p3/p3.go

@@ -0,0 +1,10 @@
+package p3
+
+import (
+	"errors"
+)
+
+// ReturnErr returns an error.
+func ReturnErr() error {
+	return errors.New("test") // @trace
+}