add test for multi processors

example/anyflow/BUILD

@@ -0,0 +1,7 @@
+cc_binary(
+  name = 'anyflow_multi_nodes',
+  srcs = ['anyflow_multi_nodes.cpp'],
+  deps = [
+    '@com_baidu_babylon//:anyflow',
+  ],
+)

example/anyflow/WORKSPACE

@@ -0,0 +1,43 @@
+workspace(name = 'example')
+
+load('@bazel_tools//tools/build_defs/repo:http.bzl', 'http_archive')
+
+################################################################################
+# babylon
+http_archive(
+  name = 'com_baidu_babylon',
+  urls = ['https://github.com/baidu/babylon/archive/refs/tags/v1.1.5.tar.gz'],
+  strip_prefix = 'babylon-1.1.5',
+  sha256 = 'a8d37251972a522b4c6f4d28ac6bf536444ff0e0c0e47eebff37aa75ca2a65a6',
+)
+################################################################################
+
+################################################################################
+# copy from WORKSPACE of babylon
+http_archive(
+  name = 'com_google_absl',
+  urls = ['https://github.com/abseil/abseil-cpp/archive/refs/tags/20230802.1.tar.gz'],
+  strip_prefix = 'abseil-cpp-20230802.1',
+  sha256 = '987ce98f02eefbaf930d6e38ab16aa05737234d7afbab2d5c4ea7adbe50c28ed',
+)
+
+http_archive(
+  name = 'com_google_protobuf',
+  urls = ['https://github.com/protocolbuffers/protobuf/archive/refs/tags/v25.3.tar.gz'],
+  strip_prefix = 'protobuf-25.3',
+  sha256 = 'd19643d265b978383352b3143f04c0641eea75a75235c111cc01a1350173180e',
+  patches = ['@com_baidu_babylon//:registry/modules/protobuf/25.3.arenastring/patches/arenastring.patch'],
+  patch_args = ['-p1'],
+)
+load("@com_google_protobuf//:protobuf_deps.bzl", "protobuf_deps")
+protobuf_deps()
+
+http_archive(
+  name = 'com_github_nelhage_rules_boost',
+  urls = ['https://github.com/nelhage/rules_boost/archive/4ab574f9a84b42b1809978114a4664184716f4bf.tar.gz'],
+  strip_prefix = 'rules_boost-4ab574f9a84b42b1809978114a4664184716f4bf',
+  sha256 = '2215e6910eb763a971b1f63f53c45c0f2b7607df38c96287666d94d954da8cdc',
+)
+load("@com_github_nelhage_rules_boost//:boost/boost.bzl", "boost_deps")
+boost_deps()
+################################################################################

example/anyflow/anyflow_multi_nodes.cpp

@@ -0,0 +1,121 @@
+#include "babylon/anyflow/builder.h"
+
+#include <iostream>
+
+using ::babylon::anyflow::GraphBuilder;
+using ::babylon::anyflow::GraphProcessor;
+
+struct AddProcessor : public GraphProcessor {
+  virtual int process() noexcept override {
+    *c.emit() = *a + *b;
+    return 0;
+  }
+
+  ANYFLOW_INTERFACE(ANYFLOW_DEPEND_DATA(int32_t, a, 0)
+                        ANYFLOW_DEPEND_DATA(int32_t, b, 1)
+                            ANYFLOW_EMIT_DATA(int32_t, c))
+};
+
+struct SubtractProcessor : public GraphProcessor {
+  virtual int process() noexcept override {
+    *c.emit() = *a - *b;
+    return 0;
+  }
+
+  ANYFLOW_INTERFACE(ANYFLOW_DEPEND_DATA(int32_t, a, 0)
+                        ANYFLOW_DEPEND_DATA(int32_t, b, 1)
+                            ANYFLOW_EMIT_DATA(int32_t, c))
+};
+
+struct MultiplyProcessor : public GraphProcessor {
+  virtual int process() noexcept override {
+    *c.emit() = (*a) * (*b);
+    return 0;
+  }
+
+  ANYFLOW_INTERFACE(ANYFLOW_DEPEND_DATA(int32_t, a, 0)
+                        ANYFLOW_DEPEND_DATA(int32_t, b, 1)
+                            ANYFLOW_EMIT_DATA(int32_t, c))
+};
+
+int main() {
+  // let A = 10, B = 5
+  // try to prove that (A + B) * (A - B) = A * A - B * B
+  int input_a = 10;
+  int input_b = 5;
+  int res_left = 0;
+  int res_right = 0;
+  {
+    GraphBuilder builder;
+
+    auto& v1 = builder.add_vertex([] {
+      return ::std::unique_ptr<AddProcessor>(new AddProcessor);
+    });
+    v1.named_depend("a").to("A");
+    v1.named_depend("b").to("B");
+    v1.named_emit("c").to("AddRes");
+
+    auto& v2 = builder.add_vertex([] {
+      return ::std::unique_ptr<SubtractProcessor>(new SubtractProcessor);
+    });
+    v2.named_depend("a").to("A");
+    v2.named_depend("b").to("B");
+    v2.named_emit("c").to("SubtractRes");
+
+    auto& v3 = builder.add_vertex([] {
+      return ::std::unique_ptr<MultiplyProcessor>(new MultiplyProcessor);
+    });
+    v3.named_depend("a").to("AddRes");
+    v3.named_depend("b").to("SubtractRes");
+    v3.named_emit("c").to("FinalRes");
+
+    builder.finish();
+    auto graph = builder.build();
+    auto a = graph->find_data("A");
+    auto b = graph->find_data("B");
+    auto final_res = graph->find_data("FinalRes");
+
+    *(a->emit<int>()) = input_a;
+    *(b->emit<int>()) = input_b;
+    graph->run(final_res);
+    res_left = *final_res->value<int>();
+  }
+  {
+    GraphBuilder builder;
+
+    auto& v1 = builder.add_vertex([] {
+      return ::std::unique_ptr<MultiplyProcessor>(new MultiplyProcessor);
+    });
+    v1.named_depend("a").to("A");
+    v1.named_depend("b").to("A");
+    v1.named_emit("c").to("MultiplyResForA");
+
+    auto& v2 = builder.add_vertex([] {
+      return ::std::unique_ptr<MultiplyProcessor>(new MultiplyProcessor);
+    });
+    v2.named_depend("a").to("B");
+    v2.named_depend("b").to("B");
+    v2.named_emit("c").to("MultiplyResForB");
+
+    auto& v3 = builder.add_vertex([] {
+      return ::std::unique_ptr<SubtractProcessor>(new SubtractProcessor);
+    });
+    v3.named_depend("a").to("MultiplyResForA");
+    v3.named_depend("b").to("MultiplyResForB");
+    v3.named_emit("c").to("FinalRes");
+
+    builder.finish();
+    auto graph = builder.build();
+    auto a = graph->find_data("A");
+    auto b = graph->find_data("B");
+    auto final_res = graph->find_data("FinalRes");
+
+    *(a->emit<int>()) = input_a;
+    *(b->emit<int>()) = input_b;
+    graph->run(final_res);
+    res_right = *final_res->value<int>();
+  }
+  ::std::cout << "(A + B) * (A - B) = " << res_left << '\n';
+  ::std::cout << "A * A - B * B = " << res_right << '\n';
+  return 0;
+}

example/anyflow/build.sh

@@ -0,0 +1,4 @@
+#!/bin/sh
+set -ex
+
+bazel build //...