Add nosnapshot executables for faster incremental builds (#359)

Fixes #311.

.travis.yml

@@ -42,10 +42,12 @@ install:
  - gn args $BUILD_PATH --list
  - ccache -s
  # Travis hangs without -j2 argument to ninja.
- - ninja -j2 -C $BUILD_PATH mock_runtime_test handlers_test deno_cc deno
+ - ninja -j2 -C $BUILD_PATH mock_runtime_test handlers_test deno_cc deno_cc_nosnapshot deno deno_nosnapshot
 script:
  - ./tools/lint.py
  - $BUILD_PATH/mock_runtime_test
  - $BUILD_PATH/handlers_test
  - $BUILD_PATH/deno_cc foo bar
+ - $BUILD_PATH/deno_cc_nosnapshot foo bar
  - $BUILD_PATH/deno meow
+ - $BUILD_PATH/deno_nosnapshot meow

BUILD.gn

@@ -15,9 +15,16 @@ config("deno_config") {
 rust_executable("deno") {
   source_root = "src/main.rs"
   extern = [ "$rust_build:libc" ]
-  deps = [
-    ":libdeno",
-  ]
+  deps = [ ":libdeno" ]
+}
+
+# This target is for fast incremental development.
+# When modifying the javascript runtime, this target will not go through the
+# extra process of building a snapshot and instead load the bundle from disk.
+rust_executable("deno_nosnapshot") {
+  source_root = "src/main.rs"
+  extern = [ "$rust_build:libc" ]
+  deps = [ ":libdeno_nosnapshot" ]
 }
 
 rust_staticlib("handlers") {
@@ -49,6 +56,22 @@ executable("deno_cc") {
   configs += [ ":deno_config" ]
 }
 
+# This target is for fast incremental development.
+# When modifying the javascript runtime, this target will not go through the
+# extra process of building a snapshot and instead load the bundle from disk.
+executable("deno_cc_nosnapshot") {
+  sources = [
+    "src/main.cc",
+  ]
+  deps = [
+    ":flatbufferjs",
+    ":handlers",
+    ":libdeno_nosnapshot",
+    ":msg_cpp",
+  ]
+  configs += [ ":deno_config" ]
+}
+
 executable("mock_runtime_test") {
   testonly = true
   sources = [
@@ -58,7 +81,7 @@ executable("mock_runtime_test") {
   ]
   deps = [
     ":create_snapshot_mock_runtime",
-    ":deno_nosnapshot",
+    ":deno_bindings",
     "//testing/gtest:gtest",
   ]
   defines = [ "DENO_MOCK_RUNTIME" ]
@@ -72,12 +95,12 @@ static_library("libdeno") {
   ]
   deps = [
     ":create_snapshot_deno",
-    ":deno_nosnapshot",
+    ":deno_bindings",
   ]
   configs += [ ":deno_config" ]
 }
 
-v8_source_set("deno_nosnapshot") {
+v8_source_set("deno_bindings") {
   sources = [
     "src/binding.cc",
     "src/deno.h",
@@ -96,7 +119,7 @@ executable("snapshot_creator") {
     "src/snapshot_creator.cc",
   ]
   deps = [
-    ":deno_nosnapshot",
+    ":deno_bindings",
   ]
   configs += [ ":deno_config" ]
 }
@@ -139,6 +162,20 @@ run_node("bundle") {
   ]
 }
 
+source_set("libdeno_nosnapshot") {
+  sources = [
+    "src/from_filesystem.cc",
+  ]
+  deps = [
+    ":bundle",
+    ":deno_bindings",
+  ]
+  configs += [ ":deno_config" ]
+  bundle_outputs = get_target_outputs(":bundle")
+  bundle_location = rebase_path(bundle_outputs[0])
+  defines = [ "BUNDLE_LOCATION=\"$bundle_location\"" ]
+}
+
 # Due to bugs in Parcel we must run TSC independently in order to catch errors.
 # https://github.com/parcel-bundler/parcel/issues/954
 run_node("run_tsc") {

src/from_filesystem.cc

@@ -0,0 +1,51 @@
+// Copyright 2018 Ryan Dahl <ry@tinyclouds.org>
+// All rights reserved. MIT License.
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <string>
+
+#include "third_party/v8/include/v8.h"
+#include "third_party/v8/src/base/logging.h"
+
+#include "deno.h"
+#include "file_util.h"
+#include "internal.h"
+
+namespace deno {
+
+Deno* NewFromFileSystem(void* data, deno_recv_cb cb) {
+  printf("Reading javascript runtime bundle from " BUNDLE_LOCATION "\n");
+
+  std::string js_source;
+  CHECK(deno::ReadFileToString(BUNDLE_LOCATION, &js_source));
+
+  Deno* d = new Deno;
+  d->currentArgs = nullptr;
+  d->cb = cb;
+  d->data = data;
+  v8::Isolate::CreateParams params;
+  params.array_buffer_allocator =
+      v8::ArrayBuffer::Allocator::NewDefaultAllocator();
+  v8::Isolate* isolate = v8::Isolate::New(params);
+  AddIsolate(d, isolate);
+
+  v8::Locker locker(isolate);
+  v8::Isolate::Scope isolate_scope(isolate);
+  {
+    v8::HandleScope handle_scope(isolate);
+    auto context = v8::Context::New(isolate);
+    InitializeContext(isolate, context, BUNDLE_LOCATION, js_source.c_str());
+    d->context.Reset(d->isolate, context);
+  }
+
+  return d;
+}
+
+}  // namespace deno
+
+extern "C" {
+Deno* deno_new(void* data, deno_recv_cb cb) {
+  return deno::NewFromFileSystem(data, cb);
+}
+}