build: add "include_js_files_for_snapshotting" Cargo feature (#17826)

This allows to not include source code into the binary (because
it will already be included in the V8 snapshot).

Nothing changes for the embedders - everything should still build the
same.

This commit brings the binary size from 87Mb to 82Mb on M1.

Alternative to https://github.com/denoland/deno/pull/17820 and
https://github.com/denoland/deno/pull/17653

---------

Co-authored-by: Leo Kettmeir <crowlkats@toaxl.com>

1 files changed, 14 insertions, 4 deletions

diff --git a/runtime/js.rs b/runtime/js.rs
index 82e58a09c..57b1e7be4 100644
--- a/runtime/js.rs
+++ b/runtime/js.rs
@@ -1,16 +1,21 @@
 // Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
+#[cfg(not(feature = "dont_create_runtime_snapshot"))]
 use deno_core::Snapshot;
+#[cfg(not(feature = "dont_create_runtime_snapshot"))]
 use log::debug;
+#[cfg(not(feature = "dont_create_runtime_snapshot"))]
 use once_cell::sync::Lazy;
 
+#[cfg(not(feature = "dont_create_runtime_snapshot"))]
+static COMPRESSED_RUNTIME_SNAPSHOT: &[u8] =
+  include_bytes!(concat!(env!("OUT_DIR"), "/RUNTIME_SNAPSHOT.bin"));
+
+#[cfg(not(feature = "dont_create_runtime_snapshot"))]
 pub static RUNTIME_SNAPSHOT: Lazy<Box<[u8]>> = Lazy::new(
   #[allow(clippy::uninit_vec)]
   #[cold]
   #[inline(never)]
   || {
-    static COMPRESSED_RUNTIME_SNAPSHOT: &[u8] =
-      include_bytes!(concat!(env!("OUT_DIR"), "/RUNTIME_SNAPSHOT.bin"));
-
     let size =
       u32::from_le_bytes(COMPRESSED_RUNTIME_SNAPSHOT[0..4].try_into().unwrap())
         as usize;
@@ -29,10 +34,15 @@ pub static RUNTIME_SNAPSHOT: Lazy<Box<[u8]>> = Lazy::new(
   },
 );
 
+#[cfg(not(feature = "dont_create_runtime_snapshot"))]
 pub fn deno_isolate_init() -> Snapshot {
   debug!("Deno isolate init with snapshots.");
   Snapshot::Static(&RUNTIME_SNAPSHOT)
 }
 
-#[cfg(feature = "snapshot_from_snapshot")]
+#[cfg(not(feature = "include_js_files_for_snapshotting"))]
 pub static SOURCE_CODE_FOR_99_MAIN_JS: &str = include_str!("js/99_main.js");
+
+#[cfg(feature = "include_js_files_for_snapshotting")]
+pub static PATH_FOR_99_MAIN_JS: &str =
+  concat!(env!("CARGO_MANIFEST_DIR"), "/js/99_main.js");