Fix version without git

build.rs

@@ -1,24 +1,21 @@
 use anyhow::Result;
-use vergen_gitcl::{BuildBuilder, Emitter, GitclBuilder};
+use vergen_gitcl::{Emitter, GitclBuilder};
 
 fn main() -> Result<()> {
-    let mut emitter = Emitter::default();
-
-    let gitcl_res = GitclBuilder::default()
+    let gitcl = GitclBuilder::default()
         .describe(true, true, Some("[0-9]*"))
-        .build();
+        .build()?;
 
-    if let Ok(gitcl) = gitcl_res {
-        emitter.add_instructions(&gitcl)?;
-    } else {
-        let build = BuildBuilder::default()
-            .build()
-            .expect("non-git vergen should succeed");
-        emitter.add_instructions(&build)?;
-    }
+    let gitcl_res = Emitter::default()
+        .idempotent()
+        .fail_on_error()
+        .add_instructions(&gitcl)
+        .and_then(|emitter| emitter.emit());
 
-    // Generate the instructions
-    emitter.emit()?;
+    if let Err(e) = gitcl_res {
+        eprintln!("error occured while generating instructions: {e:?}");
+        Emitter::default().idempotent().fail_on_error().emit()?;
+    }
 
     Ok(())
 }