added tests and functionality for default 'service' (no name given) from serverless config file

Author: Ben Gowers

__test__/util/serverlessConfigParser.test.js

@@ -32,6 +32,15 @@ functions:
             authorizerId:
               Ref: ApiGatewayAuthorizer
 `;
+const TEST_YAML_DEFAULT_STACKNAME = `
+service: test-\${opt:testArg1}
+
+provider:
+  name: aws
+  runtime: nodejs10.x
+  region: eu-west-1
+  stage: \${opt:stage, 'dev'}
+`;
 
 // eslint-disable-next-line no-template-curly-in-string
 const STACK_NAME_OPT = "test-${opt:testArg1}";
@@ -145,4 +154,11 @@ describe("Serverless Config Parsing", () => {
     expect(SLS.getStackName("dev")).toBe(null);
     expect(SLS.getRegion()).toBe(null);
   });
+
+  it(`should parse the stack name from a serverless config file when a default
+  value for 'service' (not service.name) is used`, () => {
+    const SLS = setupConfigParser(TEST_YAML_DEFAULT_STACKNAME);
+    const stage = "test";
+    expect(SLS.getStackName(stage)).toBe("test-backend-test");
+  });
 });

src/services/severlessConfigParser/serverlessConfigParser.js

@@ -22,12 +22,25 @@ class ServerlessConfigParser {
 
     if (!this.config) return;
 
+    if (this.isNameNotInService()) {
+      const name = this.config.service;
+      this.config.service = { name };
+    }
+
     this.config.service.name = replaceStacknameOpt(
       this.config.service.name,
       options
     );
   }
 
+  isNameNotInService() {
+    return (
+      (typeof this.config.service === "object" &&
+        !("name" in this.config.service)) ||
+      !(typeof this.config.service === "object")
+    );
+  }
+
   getFunctionConfig(functionName) {
     if (this.config && this.config.functions) {
       return this.config.functions[functionName];