1 files changed, 149 insertions, 0 deletions
diff --git a/misc/swig/swig_test.go b/misc/swig/swig_test.go
new file mode 100644
index 0000000000..cbe062ae41
--- /dev/null
+++ b/misc/swig/swig_test.go
@@ -0,0 +1,149 @@
+// Copyright 2023 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.
+
+//go:build cgo
+
+package swig
+
+import (
+	"bytes"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
+	"sync"
+	"testing"
+)
+
+func TestStdio(t *testing.T) {
+	mustHaveSwig(t)
+	run(t, "testdata/stdio", false)
+}
+
+func TestCall(t *testing.T) {
+	mustHaveSwig(t)
+	mustHaveCxx(t)
+	run(t, "testdata/callback", false, "Call")
+	t.Run("lto", func(t *testing.T) { run(t, "testdata/callback", true, "Call") })
+}
+
+func TestCallback(t *testing.T) {
+	mustHaveSwig(t)
+	mustHaveCxx(t)
+	run(t, "testdata/callback", false, "Callback")
+	t.Run("lto", func(t *testing.T) { run(t, "testdata/callback", true, "Callback") })
+}
+
+func run(t *testing.T, dir string, lto bool, args ...string) {
+	runArgs := append([]string{"run", "."}, args...)
+	cmd := exec.Command("go", runArgs...)
+	cmd.Dir = dir
+	if lto {
+		const cflags = "-flto -Wno-lto-type-mismatch -Wno-unknown-warning-option"
+		cmd.Env = append(cmd.Environ(),
+			"CGO_CFLAGS="+cflags,
+			"CGO_CXXFLAGS="+cflags,
+			"CGO_LDFLAGS="+cflags)
+	}
+	out, err := cmd.CombinedOutput()
+	if string(out) != "OK\n" {
+		t.Errorf("%s", string(out))
+	}
+	if err != nil {
+		t.Errorf("%s", err)
+	}
+}
+
+func mustHaveCxx(t *testing.T) {
+	// Ask the go tool for the CXX it's configured to use.
+	cxx, err := exec.Command("go", "env", "CXX").CombinedOutput()
+	if err != nil {
+		t.Fatalf("go env CXX failed: %s", err)
+	}
+	cxx = bytes.TrimSuffix(cxx, []byte("\n"))
+	// TODO(austin): "go env CXX" can return a quoted list. Use quoted.Split.
+	p, err := exec.LookPath(string(cxx))
+	if p == "" {
+		t.Skipf("test requires C++ compiler, but failed to find %s: %s", string(cxx), err)
+	}
+}
+
+var (
+	swigOnce sync.Once
+	haveSwig bool
+)
+
+func mustHaveSwig(t *testing.T) {
+	swigOnce.Do(func() {
+		mustHaveSwigOnce(t)
+		haveSwig = true
+	})
+	// The first call will skip t with a nice message. On later calls, we just skip.
+	if !haveSwig {
+		t.Skip("swig not found")
+	}
+}
+
+func mustHaveSwigOnce(t *testing.T) {
+	swig, err := exec.LookPath("swig")
+	if err != nil {
+		t.Skipf("swig not in PATH: %s", err)
+	}
+
+	// Check that swig was installed with Go support by checking
+	// that a go directory exists inside the swiglib directory.
+	// See https://golang.org/issue/23469.
+	output, err := exec.Command(swig, "-go", "-swiglib").Output()
+	if err != nil {
+		t.Skip("swig is missing Go support")
+	}
+	swigDir := strings.TrimSpace(string(output))
+
+	_, err = os.Stat(filepath.Join(swigDir, "go"))
+	if err != nil {
+		t.Skip("swig is missing Go support")
+	}
+
+	// Check that swig has a new enough version.
+	// See https://golang.org/issue/22858.
+	out, err := exec.Command(swig, "-version").CombinedOutput()
+	if err != nil {
+		t.Skipf("failed to get swig version:%s\n%s", err, string(out))
+	}
+
+	re := regexp.MustCompile(`[vV]ersion +(\d+)([.]\d+)?([.]\d+)?`)
+	matches := re.FindSubmatch(out)
+	if matches == nil {
+		// Can't find version number; hope for the best.
+		t.Logf("failed to find swig version, continuing")
+		return
+	}
+
+	var parseError error
+	atoi := func(s string) int {
+		x, err := strconv.Atoi(s)
+		if err != nil && parseError == nil {
+			parseError = err
+		}
+		return x
+	}
+	var major, minor, patch int
+	major = atoi(string(matches[1]))
+	if len(matches[2]) > 0 {
+		minor = atoi(string(matches[2][1:]))
+	}
+	if len(matches[3]) > 0 {
+		patch = atoi(string(matches[3][1:]))
+	}
+	if parseError != nil {
+		t.Logf("error parsing swig version %q, continuing anyway: %s", string(matches[0]), parseError)
+		return
+	}
+	t.Logf("found swig version %d.%d.%d", major, minor, patch)
+	if major < 3 || (major == 3 && minor == 0 && patch < 6) {
+		t.Skip("test requires swig 3.0.6 or later")
+	}
+}