test: add test for log level exclusiveness

test/logger.spec.ts

@@ -311,6 +311,38 @@ export class LoggerSpec {
     expect(spy).not.to.have.been.called();
   }
 
+  @test
+  'log level exclusiveness'() {
+    const warnSpy = LoggerSpec.sandbox.on(console, 'warn', () => {
+      // noop WARN
+    });
+    const infoSpy = LoggerSpec.sandbox.on(console, 'info', () => {
+      // noop INFO
+    });
+    const okSpy = LoggerSpec.sandbox.on(console, 'log', () => {
+      // noop OK
+    });
+
+    // only warn and info = warn + info = 4 + 1 = 5
+    process.env.STAPPS_LOG_LEVEL = '5';
+
+    Logger.warn('Foo');
+    Logger.info('Bar');
+    Logger.ok('Baz');
+
+    expect(warnSpy).to.have.been.called();
+    expect(warnSpy.__spy.calls[0][0]).to.contain('[WARN]');
+    expect(warnSpy.__spy.calls[0][0]).to.contain('Foo');
+
+    expect(infoSpy).to.have.been.called();
+    expect(infoSpy.__spy.calls[0][0]).to.contain('[INFO]');
+    expect(infoSpy.__spy.calls[0][0]).to.contain('Bar');
+
+    expect(okSpy).to.not.have.been.called();
+
+    delete process.env.STAPPS_LOG_LEVEL;
+  }
+
   @test
   getLogLevel() {
     const savedProcess = process;