diesel-rs/diesel · error

Failed to receive migrations dir from

Error message

Failed to receive migrations dir from {migrations_path_opt:?}

What it means

The migration embedding macro could not resolve a migrations directory from the given or default path. The offending input is the migration path option; the directory lookup failed before any migration file was read.

Solutions

1. Pass an explicit, valid migrations directory path
2. Ensure the default migrations directory exists and is readable
3. Check the path spelling and remove stray quotes

When it happens

Trigger: Thrown at diesel_migrations/migrations_macros/src/embed_migrations.rs:16 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of diesel-rs/diesel@6fa6ed01b2 (2026-09-07). Data as JSON: /api/errors/6482c93697ac08ca. Report an issue: GitHub.

Appendix: source

Thrown at diesel_migrations/migrations_macros/src/embed_migrations.rs:16

use crate::migrations::migration_directory_from_given_path;
use migrations_internals::{TomlMetadata, migrations_directories, version_from_string};
use quote::quote;
use std::error::Error;
use std::fs::DirEntry;
use std::path::Path;

pub fn expand(path: String) -> proc_macro2::TokenStream {
    let migrations_path_opt = if path.is_empty() {
        None
    } else {
        Some(path.replace('"', ""))
    };
    let migrations_expr = migration_directory_from_given_path(migrations_path_opt.as_deref())
        .unwrap_or_else(|_| {
            panic!("Failed to receive migrations dir from {migrations_path_opt:?}")
        });
    let embedded_migrations =
        migration_literals_from_path(&migrations_expr).expect("Failed to read migration literals");

    quote! {
        diesel_migrations::EmbeddedMigrations::new(&[#(#embedded_migrations,)*])
    }
}

fn migration_literals_from_path(
    path: &Path,
) -> Result<Vec<proc_macro2::TokenStream>, Box<dyn Error>> {
    let mut migrations = migrations_directories(path)?.collect::<Result<Vec<_>, _>>()?;

    migrations.sort_by_key(DirEntry::path);

    Ok(migrations
        .into_iter()

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