fixup: timestamp version

Author: hansl

dfx/src/lib/env.rs

@@ -174,15 +174,25 @@ impl VersionEnv for GlobalEnvironment {
 
 impl GlobalEnvironment {
     pub fn from_current_dir() -> DfxResult<GlobalEnvironment> {
-        let mut version = DFX_VERSION.to_owned();
-
         #[cfg(debug_assertions)]
         {
             // In debug, add a timestamp of the compilation at the end of version to ensure all
             // debug runs are unique (and cached uniquely).
-            version = version + "-" + env!("DFX_TIMESTAMP_DEBUG_MODE_ONLY");
+            Ok(GlobalEnvironment {
+                version: format!(
+                    "{}-{:?}",
+                    DFX_VERSION.to_owned(),
+                    std::env::var_os("DFX_TIMESTAMP_DEBUG_MODE_ONLY")
+                        .unwrap_or_else(|| std::ffi::OsString::from("local-debug"))
+                ),
+            })
         }
 
-        Ok(GlobalEnvironment { version })
+        #[cfg(not(debug_assertions))]
+        {
+            Ok(GlobalEnvironment {
+                version: DFX_VERSION.to_owned(),
+            })
+        }
     }
 }