Add EProcessErrorCode::CannotStartProcess

Surprisingly there was no clear way to tell that process hasn't been started.

---
a001c76e5418ae090191ad17a5e6d40086db1114

Pull Request resolved: https://github.com/ytsaurus/ytsaurus/pull/598

2 files changed, 5 insertions, 1 deletions

diff --git a/yt/yt/core/misc/public.h b/yt/yt/core/misc/public.h
index b43ad3d9f6..77464ae366 100644
--- a/yt/yt/core/misc/public.h
+++ b/yt/yt/core/misc/public.h
@@ -167,6 +167,7 @@ DEFINE_ENUM(EProcessErrorCode,
     ((NonZeroExitCode)    (10000))
     ((Signal)             (10001))
     ((CannotResolveBinary)(10002))
+    ((CannotStartProcess) (10003))
 );
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/yt/yt/library/process/process.cpp b/yt/yt/library/process/process.cpp
index 7dfe79e2fb..12f1be525a 100644
--- a/yt/yt/library/process/process.cpp
+++ b/yt/yt/library/process/process.cpp
@@ -755,7 +755,10 @@ TFuture<void> TProcessBase::Spawn()
 
         DoSpawn();
     } catch (const std::exception& ex) {
-        FinishedPromise_.TrySet(ex);
+        FinishedPromise_.TrySet(TError(EProcessErrorCode::CannotStartProcess,
+            "Cannot spawn child process (Path: %v)",
+            ResolvedPath_)
+            << ex);
     }
     return FinishedPromise_;
 }