fix(prepare): store temporary query files inside the workspace

sqlx-macros-core/src/query/data.rs

@@ -157,10 +157,17 @@ where
         }
     }
 
-    pub(super) fn save_in(&self, dir: impl AsRef<Path>) -> crate::Result<()> {
+    pub(super) fn save_in(
+        &self,
+        dir: impl AsRef<Path>,
+        tmp_dir: impl AsRef<Path>,
+    ) -> crate::Result<()> {
         // Output to a temporary file first, then move it atomically to avoid clobbering
         // other invocations trying to write to the same path.
-        let mut tmp_file = tempfile::NamedTempFile::new()
+
+        // Use a temp directory inside the workspace to avoid potential issues
+        // with persisting the file across filesystems.
+        let mut tmp_file = tempfile::NamedTempFile::new_in(tmp_dir)
             .map_err(|err| format!("failed to create query file: {:?}", err))?;
         serde_json::to_writer_pretty(tmp_file.as_file_mut(), self)
             .map_err(|err| format!("failed to serialize query data to file: {:?}", err))?;

sqlx-macros-core/src/query/mod.rs

@@ -357,6 +357,19 @@ where
         if let Ok(dir) = env("SQLX_OFFLINE_DIR") {
             let path = PathBuf::from(&dir);
 
+            // Prefer SQLX_TMP if set explicitly.
+            // Otherwise fallback to CARGO_TARGET_DIR and then the standard target directory.
+            let tmp_dir = if let Ok(tmp_dir) = env("SQLX_TMP") {
+                PathBuf::from(tmp_dir)
+            } else if let Ok(target_dir) = env("CARGO_TARGET_DIR") {
+                PathBuf::from(target_dir)
+            } else {
+                let tmp_target = PathBuf::from("./target/sqlx");
+                fs::create_dir_all(&tmp_target)
+                    .map_err(|e| format!("Error creating cache directory: {e:?}"))?;
+                tmp_target
+            };
+
             match fs::metadata(&path) {
                 Err(e) => {
                     if e.kind() != io::ErrorKind::NotFound {
@@ -376,7 +389,7 @@ where
                     }
 
                     // .sqlx exists and is a directory, store data.
-                    data.save_in(path)?;
+                    data.save_in(path, tmp_dir)?;
                 }
             }
         }