[typescript] Prevent generating invalid enum code due to empty variable names

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/TypeScriptClientCodegen.java

@@ -311,9 +311,25 @@ public String toEnumVarName(String name, String datatype) {
 
         if (enumName.matches("\\d.*")) { // starts with number
             return "_" + enumName;
-        } else {
-            return enumName;
         }
+
+        if (enumName.isEmpty()) {
+            // After sanitizing *all* characters (e.g. multibyte characters), the var name becomes an empty string.
+            // An empty string would cause a syntax error, so this code attempts to re-sanitize the name using another sanitizer that allows a wider variety of characters.
+            // For backward compatibility, this additional sanitization is only applied if the original sanitized name is empty.
+            final String sanitized = sanitizeNameForTypeScriptSymbol(name);
+            if (sanitized.isEmpty()) {
+                // After re-sanitizing, this pads a pseudo var name ("STRING") if still the name is empty.
+                return "STRING";
+            }
+            return "_" + sanitized;
+        }
+
+        return enumName;
+    }
+
+    private String sanitizeNameForTypeScriptSymbol(String name) {
+        return sanitizeName(name, "[^\\p{L}\\p{Nd}\\$_]");
     }
 
     private String getNameWithEnumPropertyNaming(String name) {

modules/openapi-generator/src/test/java/org/openapitools/codegen/typescript/TypeScriptClientCodegenTest.java

@@ -5,13 +5,17 @@
 import io.swagger.v3.oas.models.PathItem;
 import io.swagger.v3.oas.models.media.*;
 import org.openapitools.codegen.*;
+import org.openapitools.codegen.config.CodegenConfigurator;
 import org.openapitools.codegen.languages.TypeScriptClientCodegen;
 import org.openapitools.codegen.model.ModelMap;
 import org.openapitools.codegen.model.ModelsMap;
 import org.openapitools.codegen.utils.ModelUtils;
 import org.testng.Assert;
 import org.testng.annotations.Test;
 
+import java.io.File;
+import java.nio.file.Files;
+import java.nio.file.Paths;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
@@ -179,4 +183,31 @@ public void testAdditionalPropertiesPutForConfigValues() throws Exception {
 
         Assert.assertEquals(codegen.getLicenseName(), licenseName);
     }
+
+    @Test
+    public void testForAllSanitizedEnum() throws Exception {
+        final File output = Files.createTempDirectory("typescriptnodeclient_").toFile();
+        output.deleteOnExit();
+
+        final CodegenConfigurator configurator = new CodegenConfigurator()
+            .setGeneratorName("typescript")
+            .setInputSpec("src/test/resources/bugs/typescript_enum_var_name_all_sanitized.yaml")
+            .setOutputDir(output.getAbsolutePath().replace("\\", "/"));
+
+        final ClientOptInput clientOptInput = configurator.toClientOptInput();
+        final DefaultGenerator generator = new DefaultGenerator();
+        final List<File> files = generator.opts(clientOptInput).generate();
+        files.forEach(File::deleteOnExit);
+
+        TestUtils.assertFileContains(
+            Paths.get(output + "/models/Greeting.ts"),
+            "export enum Greeting {\n" +
+            "    _こんにちは = 'こんにちは',\n" +
+            "    _你好 = '你好',\n" +
+            "    _안녕하세요 = '안녕하세요',\n" +
+            "    STRING = '!@#%',\n" +
+            "    STRING2 = '^&*\uD83C\uDF63'",
+            "}"
+        );
+    }
 }

modules/openapi-generator/src/test/resources/bugs/typescript_enum_var_name_all_sanitized.yaml

@@ -0,0 +1,19 @@
+openapi: "3.0.0"
+info:
+  title: Sample project
+  version: '1.0'
+  description: 'Sample API Check "API Key" '
+  license:
+    name: Apache 2.0
+    url: 'https://www.apache.org/licenses/LICENSE-2.0'
+paths: {}
+components:
+  schemas:
+    Greeting:
+      type: string
+      enum:
+        - 'こんにちは'
+        - '你好'
+        - '안녕하세요'
+        - '!@#%'
+        - '^&*🍣'