Gate .esdl warning (#1422)

src/migrations/create.rs

@@ -37,7 +37,7 @@ use crate::migrations::prompt;
 use crate::migrations::source_map::{Builder, SourceMap};
 use crate::migrations::squash;
 use crate::migrations::timeout;
-use crate::platform::{is_schema_file, tmp_file_name};
+use crate::platform::{is_legacy_schema_file, is_schema_file, tmp_file_name};
 use crate::print;
 use crate::print::style::Styler;
 use crate::question;
@@ -272,6 +272,7 @@ async fn gen_start_migration(ctx: &Context) -> anyhow::Result<(String, SourceMap
     };
 
     let mut paths: Vec<PathBuf> = Vec::new();
+    let mut has_legacy_paths: bool = false;
     while let Some(item) = dir.next_entry().await? {
         let fname = item.file_name();
         let lossy_name = fname.to_string_lossy();
@@ -280,9 +281,18 @@ async fn gen_start_migration(ctx: &Context) -> anyhow::Result<(String, SourceMap
             && item.file_type().await?.is_file()
         {
             paths.push(item.path());
+            if cfg!(feature = "gel") && is_legacy_schema_file(&lossy_name) {
+                has_legacy_paths = true;
+            }
         }
     }
 
+    if cfg!(feature = "gel") && has_legacy_paths {
+        print::warn!(
+            "Legacy schema file extension '.esdl' detected. Consider renaming them to '.gel'."
+        );
+    }
+
     paths.sort();
 
     for path in paths {