Add initial fuzz tests (#2216)

.github/workflows/build_and_test.sh

@@ -16,3 +16,4 @@ if [[ -z $(git status -s) ]]; then
     # exit 1
 fi
 "$AVALANCHE_PATH"/scripts/build_test.sh
+"$AVALANCHE_PATH"/scripts/build_fuzz.sh

scripts/build_fuzz.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+
+# Mostly taken from https://github.com/golang/go/issues/46312#issuecomment-1153345129
+
+fuzzTime=${1:-1}
+files=$(grep -r --include='**_test.go' --files-with-matches 'func Fuzz' .)
+failed=false
+for file in ${files}
+do
+    funcs=$(grep -oP 'func \K(Fuzz\w*)' $file)
+    for func in ${funcs}
+    do
+        echo "Fuzzing $func in $file"
+        parentDir=$(dirname $file)
+        go test $parentDir -run=$func -fuzz=$func -fuzztime=${fuzzTime}s
+        # If any of the fuzz tests fail, return exit code 1
+        if [ $? -ne 0 ]; then
+            failed=true
+        fi
+    done
+done
+
+if $failed; then
+    exit 1
+fi

utils/cb58/cb58_test.go

@@ -60,3 +60,19 @@ func TestEncodeDecode(t *testing.T) {
 		}
 	}
 }
+
+func FuzzEncodeDecode(f *testing.F) {
+	f.Fuzz(func(t *testing.T, data []byte) {
+		require := require.New(t)
+
+		// Encode bytes to string
+		dataStr, err := Encode(data)
+		require.NoError(err)
+
+		// Decode string to bytes
+		gotData, err := Decode(dataStr)
+		require.NoError(err)
+
+		require.Equal(data, gotData)
+	})
+}

utils/compression/gzip_compressor_test.go

@@ -76,3 +76,24 @@ func TestNewGzipCompressorWithInvalidLimit(t *testing.T) {
 	_, err := NewGzipCompressor(math.MaxInt64)
 	require.ErrorIs(err, ErrInvalidMaxSizeGzipCompressor)
 }
+
+func FuzzGzipCompressor(f *testing.F) {
+	f.Fuzz(func(t *testing.T, data []byte) {
+		require := require.New(t)
+
+		if len(data) > 2*units.MiB {
+			t.SkipNow()
+		}
+
+		compressor, err := NewGzipCompressor(2 * units.MiB)
+		require.NoError(err)
+
+		compressed, err := compressor.Compress(data)
+		require.NoError(err)
+
+		decompressed, err := compressor.Decompress(compressed)
+		require.NoError(err)
+
+		require.Equal(data, decompressed)
+	})
+}

utils/formatting/encoding_test.go

@@ -121,3 +121,17 @@ func TestDecodeNil(t *testing.T) {
 		t.Fatal("decoding the empty string should return an empty byte slice")
 	}
 }
+
+func FuzzEncodeDecode(f *testing.F) {
+	f.Fuzz(func(t *testing.T, bytes []byte) {
+		require := require.New(t)
+
+		str, err := Encode(Hex, bytes)
+		require.NoError(err)
+
+		decoded, err := Decode(Hex, str)
+		require.NoError(err)
+
+		require.Equal(bytes, decoded)
+	})
+}