test: add end-to-end testing framework (#5435)

Partial fix for #5291. For details, see [README.md](https://github.com/tendermint/tendermint/blob/erik/e2e-tests/test/e2e/README.md) and [RFC-001](https://github.com/tendermint/tendermint/blob/master/docs/rfc/rfc-001-end-to-end-testing.md).

This only includes a single test case under `test/e2e/tests/`, as a proof of concept - additional test cases will be submitted separately. A randomized testnet generator will also be submitted separately, there a currently just a handful of static testnets under `test/e2e/networks/`. This will eventually replace the current P2P tests and run in CI.

test/e2e/tests/app_test.go

@@ -0,0 +1,30 @@
+package e2e_test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	e2e "github.com/tendermint/tendermint/test/e2e/pkg"
+)
+
+// Tests that any initial state given in genesis has made it into the app.
+func TestApp_InitialState(t *testing.T) {
+	testNode(t, func(t *testing.T, node e2e.Node) {
+		switch {
+		case node.Mode == e2e.ModeSeed:
+			return
+		case len(node.Testnet.InitialState) == 0:
+			return
+		}
+
+		client, err := node.Client()
+		require.NoError(t, err)
+		for k, v := range node.Testnet.InitialState {
+			resp, err := client.ABCIQuery(ctx, "", []byte(k))
+			require.NoError(t, err)
+			assert.Equal(t, k, string(resp.Response.Key))
+			assert.Equal(t, v, string(resp.Response.Value))
+		}
+	})
+}

test/e2e/tests/e2e_test.go

@@ -0,0 +1,57 @@
+package e2e_test
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	e2e "github.com/tendermint/tendermint/test/e2e/pkg"
+)
+
+func init() {
+	// This can be used to manually specify a testnet manifest and/or node to
+	// run tests against. The testnet must have been started by the runner first.
+	//os.Setenv("E2E_MANIFEST", "networks/simple.toml")
+	//os.Setenv("E2E_NODE", "validator01")
+}
+
+var (
+	ctx = context.Background()
+)
+
+// testNode runs tests for testnet nodes. The callback function is given a
+// single node to test, running as a subtest in parallel with other subtests.
+//
+// The testnet manifest must be given as the envvar E2E_MANIFEST. If not set,
+// these tests are skipped so that they're not picked up during normal unit
+// test runs. If E2E_NODE is also set, only the specified node is tested,
+// otherwise all nodes are tested.
+func testNode(t *testing.T, testFunc func(*testing.T, e2e.Node)) {
+	manifest := os.Getenv("E2E_MANIFEST")
+	if manifest == "" {
+		t.Skip("E2E_MANIFEST not set, not an end-to-end test run")
+	}
+	if !filepath.IsAbs(manifest) {
+		manifest = filepath.Join("..", manifest)
+	}
+
+	testnet, err := e2e.LoadTestnet(manifest)
+	require.NoError(t, err)
+	nodes := testnet.Nodes
+
+	if name := os.Getenv("E2E_NODE"); name != "" {
+		node := testnet.LookupNode(name)
+		require.NotNil(t, node, "node %q not found in testnet %q", name, testnet.Name)
+		nodes = []*e2e.Node{node}
+	}
+
+	for _, node := range nodes {
+		node := *node
+		t.Run(node.Name, func(t *testing.T) {
+			t.Parallel()
+			testFunc(t, node)
+		})
+	}
+}