Add execPath function (#1743)

js/deno.ts

@@ -1,7 +1,7 @@
 // Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
 
 // Public deno module.
-export { noColor, pid, env, exit, isTTY } from "./os";
+export { noColor, pid, env, exit, isTTY, execPath } from "./os";
 export { chdir, cwd } from "./dir";
 export {
   File,

js/os.ts

@@ -12,11 +12,19 @@ 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. */
+export let execPath: string;
+
 /** @internal */
-export function setGlobals(pid_: number, noColor_: boolean): void {
+export function setGlobals(
+  pid_: number,
+  noColor_: boolean,
+  execPath_: string
+): void {
   assert(!pid);
   pid = pid_;
   noColor = noColor_;
+  execPath = execPath_;
 }
 
 interface CodeInfo {
@@ -190,7 +198,7 @@ export function start(source?: string): msg.StartRes {
 
   util.setLogDebug(startResMsg.debugFlag(), source);
 
-  setGlobals(startResMsg.pid(), startResMsg.noColor());
+  setGlobals(startResMsg.pid(), startResMsg.noColor(), startResMsg.execPath()!);
 
   return startResMsg;
 }

src/msg.fbs

@@ -65,7 +65,7 @@ union Any {
   Now,
   NowRes,
   IsTTY,
-  IsTTYRes
+  IsTTYRes,
 }
 
 enum ErrorKind: byte {
@@ -156,6 +156,7 @@ table StartRes {
   cwd: string;
   pid: uint32;
   argv: [string];
+  exec_path: string;
   debug_flag: bool;
   deps_flag: bool;
   types_flag: bool;

src/ops.rs

@@ -252,6 +252,9 @@ fn op_start(
   let cwd_off =
     builder.create_string(deno_fs::normalize_path(cwd_path.as_ref()).as_ref());
 
+  let exec_path =
+    builder.create_string(std::env::current_exe().unwrap().to_str().unwrap());
+
   let v8_version = version::v8();
   let v8_version_off = builder.create_string(v8_version);
 
@@ -270,6 +273,7 @@ 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),
       ..Default::default()
     },
   );

tests/exec_path.ts

@@ -0,0 +1 @@
+console.log(Deno.execPath);

tools/test.py

@@ -38,6 +38,12 @@ def test_no_color(deno_exe):
     print green_ok()
 
 
+def exec_path_test(deno_exe):
+    cmd = [deno_exe, "tests/exec_path.ts"]
+    output = run_output(cmd)
+    assert deno_exe in output.strip()
+
+
 def main(argv):
     if len(argv) == 2:
         build_dir = sys.argv[1]
@@ -59,6 +65,8 @@ def main(argv):
     deno_exe = os.path.join(build_dir, "deno" + executable_suffix)
     check_exists(deno_exe)
 
+    exec_path_test(deno_exe)
+
     # Internal tools testing
     run([
         "node", "./node_modules/.bin/ts-node", "--project",