Make Deno.execPath a function (denoland#2743)

And throws without allow-env

cli/msg.fbs

@@ -77,6 +77,8 @@ union Any {
   Truncate,
   HomeDir,
   HomeDirRes,
+  ExecPath,
+  ExecPathRes,
   Utime,
   WorkerGetMessage,
   WorkerGetMessageRes,
@@ -181,7 +183,6 @@ table StartRes {
   cwd: string;
   pid: uint32;
   argv: [string];
-  exec_path: string;
   main_module: string; // Absolute URL.
   debug_flag: bool;
   deps_flag: bool;
@@ -468,6 +469,12 @@ table HomeDirRes {
   path: string;
 }
 
+table ExecPath {}
+
+table ExecPathRes {
+  path: string;
+}
+
 table Utime {
   filename: string;
   atime: uint64;

cli/ops.rs

@@ -212,6 +212,7 @@ pub fn op_selector_std(inner_type: msg::Any) -> Option<CliDispatchFn> {
     msg::Any::Cwd => Some(op_cwd),
     msg::Any::Dial => Some(op_dial),
     msg::Any::Environ => Some(op_env),
+    msg::Any::ExecPath => Some(op_exec_path),
     msg::Any::Exit => Some(op_exit),
     msg::Any::Fetch => Some(op_fetch),
     msg::Any::FetchSourceFile => Some(op_fetch_source_file),
@@ -354,18 +355,6 @@ fn op_start(
   let cwd_off =
     builder.create_string(deno_fs::normalize_path(cwd_path.as_ref()).as_ref());
 
-  // Use permissions.allows_env() to bypass env request prompt.
-  let exec_path = if state.permissions.allows_env() {
-    let current_exe = std::env::current_exe().unwrap();
-    // Now apply URL parser to current exe to get fully resolved path, otherwise we might get
-    // `./` and `../` bits in `exec_path`
-    let exe_url = Url::from_file_path(current_exe).unwrap();
-    exe_url.to_file_path().unwrap().to_str().unwrap().to_owned()
-  } else {
-    "".to_owned()
-  };
-  let exec_path = builder.create_string(&exec_path);
-
   let v8_version = version::v8();
   let v8_version_off = builder.create_string(v8_version);
 
@@ -399,7 +388,6 @@ fn op_start(
       v8_version: Some(v8_version_off),
       deno_version: Some(deno_version_off),
       no_color: !ansi::use_color(),
-      exec_path: Some(exec_path),
       xeval_delim,
       ..Default::default()
     },
@@ -1787,6 +1775,36 @@ fn op_home_dir(
   ))
 }
 
+fn op_exec_path(
+  state: &ThreadSafeState,
+  base: &msg::Base<'_>,
+  data: Option<PinnedBuf>,
+) -> CliOpResult {
+  assert!(data.is_none());
+  let cmd_id = base.cmd_id();
+
+  state.check_env()?;
+
+  let builder = &mut FlatBufferBuilder::new();
+  let current_exe = std::env::current_exe().unwrap();
+  // Now apply URL parser to current exe to get fully resolved path, otherwise we might get
+  // `./` and `../` bits in `exec_path`
+  let exe_url = Url::from_file_path(current_exe).unwrap();
+  let path = exe_url.to_file_path().unwrap().to_str().unwrap().to_owned();
+  let path = Some(builder.create_string(&path));
+  let inner = msg::ExecPathRes::create(builder, &msg::ExecPathResArgs { path });
+
+  ok_buf(serialize_response(
+    cmd_id,
+    builder,
+    msg::BaseArgs {
+      inner: Some(inner.as_union_value()),
+      inner_type: msg::Any::ExecPathRes,
+      ..Default::default()
+    },
+  ))
+}
+
 fn op_resources(
   _state: &ThreadSafeState,
   base: &msg::Base<'_>,

js/os.ts

@@ -13,16 +13,10 @@ export let pid: number;
 /** Reflects the NO_COLOR environment variable: https://no-color.org/ */
 export let noColor: boolean;
 
-/** Path to the current deno process's executable file.
- * Requires the `--allow-env` flag, otherwise it'll be set to an empty `string`.
- */
-export let execPath: string;
-
-function setGlobals(pid_: number, noColor_: boolean, execPath_: string): void {
+function setGlobals(pid_: number, noColor_: boolean): void {
   assert(!pid);
   pid = pid_;
   noColor = noColor_;
-  execPath = execPath_;
 }
 
 /** Check if running in terminal.
@@ -127,7 +121,7 @@ export function start(
 
   util.setLogDebug(startResMsg.debugFlag(), source);
 
-  setGlobals(startResMsg.pid(), startResMsg.noColor(), startResMsg.execPath()!);
+  setGlobals(startResMsg.pid(), startResMsg.noColor());
 
   if (preserveDenoNamespace) {
     util.immutableDefine(window, "Deno", window.Deno);
@@ -164,3 +158,19 @@ export function homeDir(): string {
 
   return path;
 }
+
+export function execPath(): string {
+  const builder = flatbuffers.createBuilder();
+  const inner = msg.ExecPath.createExecPath(builder);
+  const baseRes = sendSync(builder, msg.Any.ExecPath, inner)!;
+  assert(msg.Any.ExecPathRes === baseRes.innerType());
+  const res = new msg.ExecPathRes();
+  assert(baseRes.inner(res) != null);
+  const path = res.path();
+
+  if (!path) {
+    throw new Error("Could not get home directory.");
+  }
+
+  return path;
+}

js/os_test.ts

@@ -56,9 +56,17 @@ testPerm({ env: false }, function homeDirPerm(): void {
 });
 
 testPerm({ env: true }, function execPath(): void {
-  assertNotEquals(Deno.execPath, "");
+  assertNotEquals(Deno.execPath(), "");
 });
 
 testPerm({ env: false }, function execPathPerm(): void {
-  assertEquals(Deno.execPath, "");
+  let caughtError = false;
+  try {
+    Deno.execPath();
+  } catch (err) {
+    caughtError = true;
+    assertEquals(err.kind, Deno.ErrorKind.PermissionDenied);
+    assertEquals(err.name, "PermissionDenied");
+  }
+  assert(caughtError);
 });

js/unit_test_runner.ts

@@ -53,7 +53,7 @@ async function main(): Promise<void> {
     const cliPerms = permsToCliFlags(perms);
     // run subsequent tests using same deno executable
     const args = [
-      Deno.execPath,
+      Deno.execPath(),
       "run",
       "--no-prompt",
       ...cliPerms,

tests/exec_path.ts

@@ -1 +1 @@
-console.log(Deno.execPath);
+console.log(Deno.execPath());