itest: add icase to node log filename + restart nodes before each icase

This commit adds the icase name to the log filename, to make it simpler
to find problematic tests. Additionally after this commit we'll restart
Alice and Bob (the base harness nodes) before each icase to start with a
clean state.

lntest/harness.go

@@ -36,6 +36,9 @@ const DefaultCSV = 4
 type NetworkHarness struct {
 	netParams *chaincfg.Params
 
+	// currentTestCase holds the name for the currently run test case.
+	currentTestCase string
+
 	// lndBinary is the full path to the lnd binary that was specifically
 	// compiled with all required itest flags.
 	lndBinary string
@@ -131,10 +134,11 @@ func (f *fakeLogger) Println(args ...interface{})               {}
 // rpc clients capable of communicating with the initial seeder nodes are
 // created. Nodes are initialized with the given extra command line flags, which
 // should be formatted properly - "--arg=value".
-func (n *NetworkHarness) SetUp(lndArgs []string) error {
+func (n *NetworkHarness) SetUp(testCase string, lndArgs []string) error {
 	// Swap out grpc's default logger with out fake logger which drops the
 	// statements on the floor.
 	grpclog.SetLogger(&fakeLogger{})
+	n.currentTestCase = testCase
 
 	// Start the initial seeder nodes within the test network, then connect
 	// their respective RPC clients.
@@ -241,21 +245,23 @@ out:
 	return nil
 }
 
-// TearDownAll tears down all active nodes within the test lightning network.
-func (n *NetworkHarness) TearDownAll() error {
-
+// TearDown tears down all active nodes within the test lightning network.
+func (n *NetworkHarness) TearDown() error {
 	for _, node := range n.activeNodes {
 		if err := n.ShutdownNode(node); err != nil {
 			return err
 		}
 	}
 
+	return nil
+}
+
+// Stop stops the test harness.
+func (n *NetworkHarness) Stop() {
 	close(n.lndErrorChan)
 	close(n.quit)
 
 	n.feeService.stop()
-
-	return nil
 }
 
 // NewNode fully initializes a returns a new HarnessNode bound to the
@@ -358,17 +364,18 @@ func (n *NetworkHarness) RestoreNodeWithSeed(name string, extraArgs []string,
 // wallet with or without a seed. If hasSeed is false, the returned harness node
 // can be used immediately. Otherwise, the node will require an additional
 // initialization phase where the wallet is either created or restored.
-func (n *NetworkHarness) newNode(name string, extraArgs []string,
-	hasSeed bool, password []byte) (*HarnessNode, error) {
+func (n *NetworkHarness) newNode(name string, extraArgs []string, hasSeed bool,
+	password []byte) (*HarnessNode, error) {
 
 	node, err := newNode(NodeConfig{
-		Name:       name,
-		HasSeed:    hasSeed,
-		Password:   password,
-		BackendCfg: n.BackendCfg,
-		NetParams:  n.netParams,
-		ExtraArgs:  extraArgs,
-		FeeURL:     n.feeService.url,
+		Name:              name,
+		LogFilenamePrefix: n.currentTestCase,
+		HasSeed:           hasSeed,
+		Password:          password,
+		BackendCfg:        n.BackendCfg,
+		NetParams:         n.netParams,
+		ExtraArgs:         extraArgs,
+		FeeURL:            n.feeService.url,
 	})
 	if err != nil {
 		return nil, err