Merge pull request #206 from fujiwara/fix/performance

Fix/performance

tfstate/lookup.go

@@ -242,32 +242,32 @@ func (s *TFState) Lookup(key string) (*Object, error) {
 // we must quote them like `.outputs["repository-arn"]`.
 //
 // quoteJQQuery does it.
-func quoteJQQuery(query string) string {
-	splitRegex := regexp.MustCompile(`[.\[\]]`)
-	indexRegex := regexp.MustCompile(`^-?[0-9]+$`)
-	parts := splitRegex.Split(query, -1)
-	parts_coalesced := make([]string, 0, len(parts))
+var (
+	quoteSplitRegex = regexp.MustCompile(`[.\[\]]`)
+	quoteIndexRegex = regexp.MustCompile(`^-?[0-9]+$`)
+)
 
-	for _, part := range parts {
-		if part != "" {
-			parts_coalesced = append(parts_coalesced, part)
-		}
+func quoteJQQuery(query string) string {
+	if query == "" || !strings.Contains(query, "-") {
+		// short-circuit if query is empty or doesn't contain hyphen
+		return query
 	}
-
+	parts := quoteSplitRegex.Split(query, -1)
 	var builder strings.Builder
+	builder.Grow(len(query) + 5*len(parts))
 	builder.WriteByte('.')
-
-	for _, part := range parts_coalesced {
+	for _, part := range parts {
+		if part == "" {
+			continue
+		}
 		builder.WriteByte('[')
-		if indexRegex.MatchString(part) {
+		if quoteIndexRegex.MatchString(part) {
 			builder.WriteString(part)
 		} else {
 			if !strings.HasPrefix(part, `"`) {
 				builder.WriteByte('"')
 			}
-
 			builder.WriteString(part)
-
 			if !strings.HasSuffix(part, `"`) {
 				builder.WriteByte('"')
 			}

tfstate/lookup_test.go

@@ -229,6 +229,25 @@ func TestLookupFileURL(t *testing.T) {
 	testLookupState(t, state)
 }
 
+func BenchmarkLookupFile(b *testing.B) {
+	f, err := os.Open("test/terraform.tfstate")
+	if err != nil {
+		b.Error(err)
+	}
+	state, err := tfstate.Read(context.Background(), f)
+	if err != nil {
+		b.Error(err)
+	}
+	for i := 0; i < b.N; i++ {
+		for _, ts := range TestSuitesOK {
+			_, err := state.Lookup(ts.Key)
+			if err != nil {
+				b.Error(err)
+			}
+		}
+	}
+}
+
 func TestLookupHTTPURL(t *testing.T) {
 	h := http.FileServer(http.Dir("."))
 	ts := httptest.NewServer(h)