test: added unit test

Author: dreamorosi

Diff for: packages/logger/src/Logger.ts

@@ -629,7 +629,7 @@ class Logger extends Utility implements ClassThatLogs {
    * @private
    * @returns {boolean}
    */
-  private isValidLogLevel(logLevel?: LogLevel | string): logLevel is LogLevel {
+  private isValidLogLevel(logLevel?: LogLevel | string): logLevel is Uppercase<LogLevel> {
     return typeof logLevel === 'string' && logLevel in this.logLevelThresholds;
   }
 
@@ -748,20 +748,25 @@ class Logger extends Utility implements ClassThatLogs {
    * @returns {void}
    */
   private setLogLevel(logLevel?: LogLevel): void {
-    if (this.isValidLogLevel(logLevel)) {
-      this.logLevel = logLevel?.toUpperCase() as Uppercase<LogLevel>;
+    const constructorLogLevel = logLevel?.toUpperCase();
+    if (this.isValidLogLevel(constructorLogLevel)) {
+      this.logLevel = constructorLogLevel;
 
       return;
     }
-    const customConfigValue = this.getCustomConfigService()?.getLogLevel();
+    const customConfigValue = this.getCustomConfigService()
+      ?.getLogLevel()
+      ?.toUpperCase();
     if (this.isValidLogLevel(customConfigValue)) {
-      this.logLevel = customConfigValue?.toUpperCase() as Uppercase<LogLevel>;
+      this.logLevel = customConfigValue;
 
       return;
     }
-    const envVarsValue = this.getEnvVarsService().getLogLevel();
+    const envVarsValue = this.getEnvVarsService()
+      ?.getLogLevel()
+      ?.toUpperCase();
     if (this.isValidLogLevel(envVarsValue)) {
-      this.logLevel = envVarsValue?.toUpperCase() as Uppercase<LogLevel>;
+      this.logLevel = envVarsValue;
 
       return;
     }

Diff for: packages/logger/tests/unit/helpers.test.ts

@@ -199,10 +199,10 @@ describe('Helper: createLogger function', () => {
       }));
     });
 
-    test('when a custom logLevel is passed, returns a Logger instance with the correct properties', () => {
+    test('when a custom uppercase logLevel is passed, returns a Logger instance with the correct properties', () => {
 
       // Prepare
-      const loggerOptions:ConstructorOptions = {
+      const loggerOptions: ConstructorOptions = {
         logLevel: 'ERROR',
       };
 
@@ -225,6 +225,36 @@ describe('Helper: createLogger function', () => {
         logLevel: 'ERROR',
         logFormatter: expect.any(PowertoolLogFormatter),
       }));
+
+    });
+    
+    test('when a custom lowercase logLevel is passed, returns a Logger instance with the correct properties', () => {
+
+      // Prepare
+      const loggerOptions: ConstructorOptions = {
+        logLevel: 'warn',
+      };
+
+      // Act
+      const logger = createLogger(loggerOptions);
+
+      // Assess
+      expect(logger).toBeInstanceOf(Logger);
+      expect(logger).toEqual(expect.objectContaining({
+        logsSampled: false,
+        persistentLogAttributes: {},
+        powertoolLogData: {
+          sampleRateValue: undefined,
+          awsRegion: 'eu-west-1',
+          environment: '',
+          serviceName: 'hello-world',
+        },
+        envVarsService: expect.any(EnvironmentVariablesService),
+        customConfigService: undefined,
+        logLevel: 'WARN',
+        logFormatter: expect.any(PowertoolLogFormatter),
+      }));
+
     });
 
     test('when no log level is set, returns a Logger instance with INFO level', () => {