build: allow deno_runtime crate to build in docs.rs (#11602)

3 files changed, 113 insertions, 91 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 352ef1164..3b01bf424 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -818,7 +818,7 @@ dependencies = [
 
 [[package]]
 name = "deno_runtime"
-version = "0.22.0"
+version = "0.22.2"
 dependencies = [
  "atty",
  "deno_broadcast_channel",
diff --git a/runtime/Cargo.toml b/runtime/Cargo.toml
index 4f1841fa2..e79b7c293 100644
--- a/runtime/Cargo.toml
+++ b/runtime/Cargo.toml
@@ -2,13 +2,17 @@
 
 [package]
 name = "deno_runtime"
-version = "0.22.0"
+version = "0.22.2"
 authors = ["the Deno authors"]
 edition = "2018"
 license = "MIT"
 repository = "https://github.com/denoland/deno"
 description = "Provides the deno runtime library"
 
+[features]
+# "fake" feature that allows to generate docs on docs.rs
+docsrs = []
+
 [lib]
 name = "deno_runtime"
 path = "lib.rs"
@@ -88,3 +92,6 @@ nix = "0.20.0"
 [dev-dependencies]
 # Used in benchmark
 test_util = { path = "../test_util" }
+
+[package.metadata.docs.rs]
+features = ["docsrs"]
diff --git a/runtime/build.rs b/runtime/build.rs
index 3003fb231..daab90215 100644
--- a/runtime/build.rs
+++ b/runtime/build.rs
@@ -1,90 +1,110 @@
 // Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.
 
-use deno_core::Extension;
-use deno_core::JsRuntime;
-use deno_core::RuntimeOptions;
 use std::env;
 use std::path::Path;
 use std::path::PathBuf;
 
-// TODO(bartlomieju): this module contains a lot of duplicated
-// logic with `cli/build.rs`, factor out to `deno_core`.
-fn create_snapshot(
-  mut js_runtime: JsRuntime,
-  snapshot_path: &Path,
-  files: Vec<PathBuf>,
-) {
-  // TODO(nayeemrmn): https://github.com/rust-lang/cargo/issues/3946 to get the
-  // workspace root.
-  let display_root = Path::new(env!("CARGO_MANIFEST_DIR")).parent().unwrap();
-  for file in files {
-    println!("cargo:rerun-if-changed={}", file.display());
-    let display_path = file.strip_prefix(display_root).unwrap();
-    let display_path_str = display_path.display().to_string();
-    js_runtime
-      .execute_script(
-        &("deno:".to_string() + &display_path_str.replace('\\', "/")),
-        &std::fs::read_to_string(&file).unwrap(),
-      )
-      .unwrap();
+// This is a shim that allows to generate documentation on docs.rs
+#[cfg(not(feature = "docsrs"))]
+mod not_docs {
+  use super::*;
+  use deno_core::Extension;
+  use deno_core::JsRuntime;
+  use deno_core::RuntimeOptions;
+
+  // TODO(bartlomieju): this module contains a lot of duplicated
+  // logic with `cli/build.rs`, factor out to `deno_core`.
+  fn create_snapshot(
+    mut js_runtime: JsRuntime,
+    snapshot_path: &Path,
+    files: Vec<PathBuf>,
+  ) {
+    // TODO(nayeemrmn): https://github.com/rust-lang/cargo/issues/3946 to get the
+    // workspace root.
+    let display_root = Path::new(env!("CARGO_MANIFEST_DIR")).parent().unwrap();
+    for file in files {
+      println!("cargo:rerun-if-changed={}", file.display());
+      let display_path = file.strip_prefix(display_root).unwrap();
+      let display_path_str = display_path.display().to_string();
+      js_runtime
+        .execute_script(
+          &("deno:".to_string() + &display_path_str.replace('\\', "/")),
+          &std::fs::read_to_string(&file).unwrap(),
+        )
+        .unwrap();
+    }
+
+    let snapshot = js_runtime.snapshot();
+    let snapshot_slice: &[u8] = &*snapshot;
+    println!("Snapshot size: {}", snapshot_slice.len());
+    std::fs::write(&snapshot_path, snapshot_slice).unwrap();
+    println!("Snapshot written to: {} ", snapshot_path.display());
   }
 
-  let snapshot = js_runtime.snapshot();
-  let snapshot_slice: &[u8] = &*snapshot;
-  println!("Snapshot size: {}", snapshot_slice.len());
-  std::fs::write(&snapshot_path, snapshot_slice).unwrap();
-  println!("Snapshot written to: {} ", snapshot_path.display());
-}
+  fn create_runtime_snapshot(snapshot_path: &Path, files: Vec<PathBuf>) {
+    let extensions: Vec<Extension> = vec![
+      deno_webidl::init(),
+      deno_console::init(),
+      deno_url::init(),
+      deno_tls::init(),
+      deno_web::init(deno_web::BlobStore::default(), Default::default()),
+      deno_fetch::init::<deno_fetch::NoFetchPermissions>(
+        "".to_owned(),
+        None,
+        None,
+        None,
+        None,
+      ),
+      deno_websocket::init::<deno_websocket::NoWebSocketPermissions>(
+        "".to_owned(),
+        None,
+        None,
+      ),
+      deno_webstorage::init(None),
+      deno_crypto::init(None),
+      deno_webgpu::init(false),
+      deno_timers::init::<deno_timers::NoTimersPermission>(),
+      deno_broadcast_channel::init(
+        deno_broadcast_channel::InMemoryBroadcastChannel::default(),
+        false, // No --unstable.
+      ),
+      deno_ffi::init::<deno_ffi::NoFfiPermissions>(false),
+      deno_net::init::<deno_net::NoNetPermissions>(
+        None, false, // No --unstable.
+        None,
+      ),
+      deno_http::init(),
+    ];
 
-fn create_runtime_snapshot(snapshot_path: &Path, files: Vec<PathBuf>) {
-  let extensions: Vec<Extension> = vec![
-    deno_webidl::init(),
-    deno_console::init(),
-    deno_url::init(),
-    deno_tls::init(),
-    deno_web::init(deno_web::BlobStore::default(), Default::default()),
-    deno_fetch::init::<deno_fetch::NoFetchPermissions>(
-      "".to_owned(),
-      None,
-      None,
-      None,
-      None,
-    ),
-    deno_websocket::init::<deno_websocket::NoWebSocketPermissions>(
-      "".to_owned(),
-      None,
-      None,
-    ),
-    deno_webstorage::init(None),
-    deno_crypto::init(None),
-    deno_webgpu::init(false),
-    deno_timers::init::<deno_timers::NoTimersPermission>(),
-    deno_broadcast_channel::init(
-      deno_broadcast_channel::InMemoryBroadcastChannel::default(),
-      false, // No --unstable.
-    ),
-    deno_ffi::init::<deno_ffi::NoFfiPermissions>(false),
-    deno_net::init::<deno_net::NoNetPermissions>(
-      None, false, // No --unstable.
-      None,
-    ),
-    deno_http::init(),
-  ];
+    let js_runtime = JsRuntime::new(RuntimeOptions {
+      will_snapshot: true,
+      extensions,
+      ..Default::default()
+    });
+    create_snapshot(js_runtime, snapshot_path, files);
+  }
 
-  let js_runtime = JsRuntime::new(RuntimeOptions {
-    will_snapshot: true,
-    extensions,
-    ..Default::default()
-  });
-  create_snapshot(js_runtime, snapshot_path, files);
-}
+  fn get_js_files(d: &str) -> Vec<PathBuf> {
+    let manifest_dir = Path::new(env!("CARGO_MANIFEST_DIR"));
+    let mut js_files = std::fs::read_dir(d)
+      .unwrap()
+      .map(|dir_entry| {
+        let file = dir_entry.unwrap();
+        manifest_dir.join(file.path())
+      })
+      .filter(|path| path.extension().unwrap_or_default() == "js")
+      .collect::<Vec<PathBuf>>();
+    js_files.sort();
+    js_files
+  }
 
-fn main() {
-  // Skip building from docs.rs.
-  if env::var_os("DOCS_RS").is_some() {
-    return;
+  pub fn build_snapshot(runtime_snapshot_path: PathBuf) {
+    let js_files = get_js_files("js");
+    create_runtime_snapshot(&runtime_snapshot_path, js_files);
   }
+}
 
+fn main() {
   // To debug snapshot issues uncomment:
   // op_fetch_asset::trace_serializer();
 
@@ -95,20 +115,15 @@ fn main() {
   // Main snapshot
   let runtime_snapshot_path = o.join("CLI_SNAPSHOT.bin");
 
-  let js_files = get_js_files("js");
-  create_runtime_snapshot(&runtime_snapshot_path, js_files);
-}
+  // If we're building on docs.rs we just create
+  // and empty snapshot file and return, because `rusty_v8`
+  // doesn't actually compile on docs.rs
+  if env::var_os("DOCS_RS").is_some() {
+    let snapshot_slice = &[];
+    std::fs::write(&runtime_snapshot_path, snapshot_slice).unwrap();
+    return;
+  }
 
-fn get_js_files(d: &str) -> Vec<PathBuf> {
-  let manifest_dir = Path::new(env!("CARGO_MANIFEST_DIR"));
-  let mut js_files = std::fs::read_dir(d)
-    .unwrap()
-    .map(|dir_entry| {
-      let file = dir_entry.unwrap();
-      manifest_dir.join(file.path())
-    })
-    .filter(|path| path.extension().unwrap_or_default() == "js")
-    .collect::<Vec<PathBuf>>();
-  js_files.sort();
-  js_files
+  #[cfg(not(feature = "docsrs"))]
+  not_docs::build_snapshot(runtime_snapshot_path)
 }