1 files changed, 61 insertions, 0 deletions
diff --git a/test/fixedbugs/issue22662b.go b/test/fixedbugs/issue22662b.go
new file mode 100644
index 0000000..df4f284
--- /dev/null
+++ b/test/fixedbugs/issue22662b.go
@@ -0,0 +1,61 @@
+// +build !js,gc
+// run
+
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Verify the impact of line directives on error positions and position formatting.
+
+package main
+
+import (
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"strings"
+)
+
+// Each of these tests is expected to fail (missing package clause)
+// at the position determined by the preceding line directive.
+var tests = []struct {
+	src, pos string
+}{
+	{"//line :10\n", ":10:"},                   // no filename means no filename
+	{"//line :10:4\n", "filename:10:4"},        // no filename means use existing filename
+	{"//line foo.go:10\n", "foo.go:10:"},       // no column means don't print a column
+	{"//line foo.go:10:4\n", "foo.go:10:4:"},   // column means print a column
+	{"//line foo.go:10:4\n\n", "foo.go:11:1:"}, // relative columns start at 1 after newline
+
+	{"/*line :10*/", ":10:"},
+	{"/*line :10:4*/", "filename:10:4"},
+	{"/*line foo.go:10*/", "foo.go:10:"},
+	{"/*line foo.go:10:4*/", "foo.go:10:4:"},
+	{"/*line foo.go:10:4*/\n", "foo.go:11:1:"},
+}
+
+func main() {
+	f, err := ioutil.TempFile("", "issue22662b.go")
+	if err != nil {
+		log.Fatal(err)
+	}
+	f.Close()
+	defer os.Remove(f.Name())
+
+	for _, test := range tests {
+		if err := ioutil.WriteFile(f.Name(), []byte(test.src), 0660); err != nil {
+			log.Fatal(err)
+		}
+
+		out, err := exec.Command("go", "tool", "compile", "-p=p", f.Name()).CombinedOutput()
+		if err == nil {
+			log.Fatalf("expected compiling\n---\n%s\n---\nto fail", test.src)
+		}
+
+		errmsg := strings.Replace(string(out), f.Name(), "filename", -1) // use "filename" instead of actual (long) filename
+		if !strings.HasPrefix(errmsg, test.pos) {
+			log.Fatalf("%q: got %q; want position %q", test.src, errmsg, test.pos)
+		}
+	}
+}