Fix error formatting based on best practices from Code Review Comments (#2615)

balancer/grpclb/grpclb_test.go

@@ -310,7 +310,7 @@ func newLoadBalancer(numberOfBackends int) (tss *testServers, cleanup func(), er
 		// Start a backend.
 		beLis, e := net.Listen("tcp", "localhost:0")
 		if e != nil {
-			err = fmt.Errorf("Failed to listen %v", err)
+			err = fmt.Errorf("failed to listen %v", err)
 			return
 		}
 		beIPs = append(beIPs, beLis.Addr().(*net.TCPAddr).IP)
@@ -323,7 +323,7 @@ func newLoadBalancer(numberOfBackends int) (tss *testServers, cleanup func(), er
 	// Start a load balancer.
 	lbLis, err := net.Listen("tcp", "localhost:0")
 	if err != nil {
-		err = fmt.Errorf("Failed to create the listener for the load balancer %v", err)
+		err = fmt.Errorf("failed to create the listener for the load balancer %v", err)
 		return
 	}
 	lbCreds := &serverNameCheckCreds{

balancer/roundrobin/roundrobin_test.go

@@ -72,7 +72,7 @@ func startTestServers(count int) (_ *test, err error) {
 	for i := 0; i < count; i++ {
 		lis, err := net.Listen("tcp", "localhost:0")
 		if err != nil {
-			return nil, fmt.Errorf("Failed to listen %v", err)
+			return nil, fmt.Errorf("failed to listen %v", err)
 		}
 
 		s := grpc.NewServer()

balancer_switching_test.go

@@ -86,7 +86,7 @@ func checkPickFirst(cc *ClientConn, servers []*server) error {
 	for i := 0; i < 3; i++ {
 		err = cc.Invoke(context.Background(), "/foo/bar", &req, &reply)
 		if errorDesc(err) != servers[0].port {
-			return fmt.Errorf("Index %d: want peer %v, got peer %v", i, servers[0].port, err)
+			return fmt.Errorf("index %d: want peer %v, got peer %v", i, servers[0].port, err)
 		}
 	}
 	return nil
@@ -122,7 +122,7 @@ func checkRoundRobin(cc *ClientConn, servers []*server) error {
 	for i := 0; i < 3*serverCount; i++ {
 		err = cc.Invoke(context.Background(), "/foo/bar", &req, &reply)
 		if errorDesc(err) != servers[i%serverCount].port {
-			return fmt.Errorf("Index %d: want peer %v, got peer %v", i, servers[i%serverCount].port, err)
+			return fmt.Errorf("index %d: want peer %v, got peer %v", i, servers[i%serverCount].port, err)
 		}
 	}
 	return nil

picker_wrapper_test.go

@@ -56,7 +56,7 @@ type testingPicker struct {
 
 func (p *testingPicker) Pick(ctx context.Context, opts balancer.PickOptions) (balancer.SubConn, func(balancer.DoneInfo), error) {
 	if atomic.AddInt64(&p.maxCalled, -1) < 0 {
-		return nil, nil, fmt.Errorf("Pick called to many times (> goroutineCount)")
+		return nil, nil, fmt.Errorf("pick called to many times (> goroutineCount)")
 	}
 	if p.err != nil {
 		return nil, nil, p.err

test/bufconn/bufconn.go

@@ -37,7 +37,7 @@ type Listener struct {
 	done chan struct{}
 }
 
-var errClosed = fmt.Errorf("Closed")
+var errClosed = fmt.Errorf("closed")
 
 // Listen returns a Listener that can only be contacted by its own Dialers and
 // creates buffered connections between the two.

test/channelz_test.go

@@ -1327,7 +1327,7 @@ func (s) TestCZSocketGetSecurityValueTLS(t *testing.T) {
 				return true, nil
 			}
 		}
-		return false, fmt.Errorf("SocketData.Security.StandardName got: %v, want it to be one of %v ", securityVal.StandardName, cipherSuites)
+		return false, fmt.Errorf("SocketData.Security.StandardName got: %v, want it to be one of %v", securityVal.StandardName, cipherSuites)
 	}); err != nil {
 		t.Fatal(err)
 	}

test/retry_test.go

@@ -386,7 +386,7 @@ func (s) TestRetryStreaming(t *testing.T) {
 	cCheckElapsed := func(d time.Duration) clientOp {
 		return func(_ testpb.TestService_FullDuplexCallClient) error {
 			if elapsed := time.Since(curTime); elapsed < d {
-				return fmt.Errorf("Elapsed time: %v; want >= %v", elapsed, d)
+				return fmt.Errorf("elapsed time: %v; want >= %v", elapsed, d)
 			}
 			return nil
 		}