[k6] bugfixes to improve the output script (#5614)

* [k6] Skip appDescription escaping

* [k6] Fix variable identifier in output

* [k6] Fix bug with reserved words handling

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/K6ClientCodegen.java

@@ -377,14 +377,14 @@ public class K6ClientCodegen extends DefaultCodegen implements CodegenConfig {
                     for (io.swagger.v3.oas.models.parameters.Parameter parameter : operation.getParameters()) {
                         switch (parameter.getIn()) {
                             case "header":
-                                httpParams.add(new Parameter(parameter.getName(), getTemplateString(parameter.getName())));
-                                extraParameters.add(new Parameter(parameter.getName(), parameter.getName().toUpperCase(Locale.ROOT)));
+                                httpParams.add(new Parameter(parameter.getName(), getTemplateString(toVarName(parameter.getName()))));
+                                extraParameters.add(new Parameter(toVarName(parameter.getName()), parameter.getName().toUpperCase(Locale.ROOT)));
                                 break;
                             case "path":
                             case "query":
                                 if (parameter.getIn().equals("query"))
-                                    queryParams.add(new Parameter(parameter.getName(), getVariable(parameter.getName())));
-                                variables.add(new Parameter(parameter.getName(), parameter.getName().toUpperCase(Locale.ROOT)));
+                                    queryParams.add(new Parameter(parameter.getName(), getTemplateVariable(parameter.getName())));
+                                variables.add(new Parameter(toVarName(parameter.getName()), parameter.getName().toUpperCase(Locale.ROOT)));
                                 break;
                             default:
                                 break;
@@ -446,12 +446,67 @@ public class K6ClientCodegen extends DefaultCodegen implements CodegenConfig {
         return reference.toString();
     }
 
-    private String getVariable(String input) {
+    private String getTemplateVariable(String input) {
         return "${" + input + "}";
     }
 
+    public String getModelPropertyNaming() {
+        return this.modelPropertyNaming;
+    }
+
+    private String getNameUsingModelPropertyNaming(String name) {
+        switch (CodegenConstants.MODEL_PROPERTY_NAMING_TYPE.valueOf(getModelPropertyNaming())) {
+            case original:
+                return name;
+            case camelCase:
+                return camelize(name, true);
+            case PascalCase:
+                return camelize(name);
+            case snake_case:
+                return underscore(name);
+            default:
+                throw new IllegalArgumentException("Invalid model property naming '" +
+                        name + "'. Must be 'original', 'camelCase', " +
+                        "'PascalCase' or 'snake_case'");
+        }
+    }
+
+    @Override
+    public String toVarName(String name) {
+        // sanitize name
+        name = sanitizeName(name);  // FIXME parameter should not be assigned. Also declare it as "final"
+
+        if ("_".equals(name)) {
+            name = "_u";
+        }
+
+        // if it's all uppper case, do nothing
+        if (name.matches("^[A-Z_]*$")) {
+            return name;
+        }
+
+        // camelize (lower first character) the variable name
+        // pet_id => petId
+        name = getNameUsingModelPropertyNaming(name);
+
+        // for reserved word or word starting with number, append _
+        if (isReservedWord(name) || name.matches("^\\d.*")) {
+            name = escapeReservedWord(name);
+        }
+
+        return name;
+    }
+
+    @Override
+    public String escapeReservedWord(String name) {
+        if (this.reservedWordsMappings().containsKey(name)) {
+            return this.reservedWordsMappings().get(name);
+        }
+        return "_" + name;
+    }
+
     private String getTemplateString(String input) {
-        return "`" + getVariable(input) + "`";
+        return "`" + getTemplateVariable(input) + "`";
     }
 
     private String getDoubleQuotedString(String input) {

modules/openapi-generator/src/main/resources/k6/licenseInfo.mustache

@@ -1,6 +1,6 @@
 /*
  * {{appName}}
- * {{appDescription}}
+ * {{& appDescription}}
  *
  {{#version}}
  * OpenAPI spec version: {{version}}

samples/client/petstore/k6/script.js

@@ -1,6 +1,6 @@
 /*
  * OpenAPI Petstore
- * This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
+ * This is a sample server Petstore server.  For this sample, you can use the api key \"special-key\" to test the authorization filters
  *
  * OpenAPI spec version: 1.0.0
  *
@@ -19,7 +19,7 @@ const BASE_URL = "http://petstore.swagger.io/v2";
 // You might want to edit the value of this variable or remove calls to the sleep function on the script.
 const SLEEP_DURATION = 0.1;
 // Global variables should be initialized.
-let api_key = "TODO_EDIT_THE_API_KEY";
+let apiKey = "TODO_EDIT_THE_API_KEY";
 
 export default function() {
     group("/pet", () => {
@@ -76,7 +76,7 @@ export default function() {
         sleep(SLEEP_DURATION);
 
         // Request No. 3
-        params = {headers: {"api_key": `${api_key}`}};
+        params = {headers: {"api_key": `${apiKey}`}};
         request = http.delete(url, params);
         sleep(SLEEP_DURATION);
     });