pkg/clangtool/tooltest: add package

Factor out common clang tool testing helpers from the declextract tool test.

1 files changed, 103 insertions, 0 deletions

diff --git a/pkg/clangtool/tooltest/tooltest.go b/pkg/clangtool/tooltest/tooltest.go
new file mode 100644
index 000000000..b9ad18a83
--- /dev/null
+++ b/pkg/clangtool/tooltest/tooltest.go
@@ -0,0 +1,103 @@
+// Copyright 2025 syzkaller project authors. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+package tooltest
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/google/syzkaller/pkg/clangtool"
+	"github.com/google/syzkaller/pkg/osutil"
+	"github.com/google/syzkaller/pkg/testutil"
+)
+
+var (
+	FlagBin    = flag.String("bin", "", "path to the clang tool binary to use")
+	FlagUpdate = flag.Bool("update", false, "update golden files")
+)
+
+func TestClangTool[Output any, OutputPtr clangtool.OutputDataPtr[Output]](t *testing.T) {
+	if *FlagBin == "" {
+		t.Skipf("clang tool path is not specified, run with -bin=clangtool flag")
+	}
+	ForEachTestFile(t, func(t *testing.T, cfg *clangtool.Config, file string) {
+		out, err := clangtool.Run[Output, OutputPtr](cfg)
+		if err != nil {
+			t.Fatal(err)
+		}
+		got, err := json.MarshalIndent(out, "", "\t")
+		if err != nil {
+			t.Fatal(err)
+		}
+		CompareGoldenData(t, file+".json", got)
+	})
+}
+
+func ForEachTestFile(t *testing.T, fn func(t *testing.T, cfg *clangtool.Config, file string)) {
+	forEachTestFile(t, func(t *testing.T, file string) {
+		t.Run(filepath.Base(file), func(t *testing.T) {
+			t.Parallel()
+			buildDir := t.TempDir()
+			commands := fmt.Sprintf(`[{
+					"file": "%s",
+					"directory": "%s",
+					"command": "clang -c %s -DKBUILD_BASENAME=foo"
+				}]`,
+				file, buildDir, file)
+			dbFile := filepath.Join(buildDir, "compile_commands.json")
+			if err := os.WriteFile(dbFile, []byte(commands), 0600); err != nil {
+				t.Fatal(err)
+			}
+			cfg := &clangtool.Config{
+				ToolBin:    *FlagBin,
+				KernelSrc:  osutil.Abs("testdata"),
+				KernelObj:  buildDir,
+				CacheFile:  filepath.Join(buildDir, filepath.Base(file)+".json"),
+				DebugTrace: &testutil.Writer{TB: t},
+			}
+			fn(t, cfg, file)
+		})
+	})
+}
+
+func forEachTestFile(t *testing.T, fn func(t *testing.T, file string)) {
+	files, err := filepath.Glob(filepath.Join(osutil.Abs("testdata"), "*.c"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(files) == 0 {
+		t.Fatal("found no source files")
+	}
+	for _, file := range files {
+		fn(t, file)
+	}
+}
+
+func CompareGoldenFile(t *testing.T, goldenFile, gotFile string) {
+	got, err := os.ReadFile(gotFile)
+	if err != nil {
+		t.Fatal(err)
+	}
+	CompareGoldenData(t, goldenFile, got)
+}
+
+func CompareGoldenData(t *testing.T, goldenFile string, got []byte) {
+	if *FlagUpdate {
+		if err := os.WriteFile(goldenFile, got, 0644); err != nil {
+			t.Fatal(err)
+		}
+	}
+	want, err := os.ReadFile(goldenFile)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if diff := cmp.Diff(want, got); diff != "" {
+		t.Fatal(diff)
+	}
+}