From 8381e87d4a368433dbf2e78532c6bbbee250811a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rapha=C3=ABl=20Th=C3=A9riault?=
 <raphael_theriault@outlook.com>
Date: Thu, 23 Jul 2020 15:25:13 -0400
Subject: [PATCH] Document migrate! (and small fixes)

---
 sqlx-core/src/migrate/migrator.rs |  2 +-
 sqlx-macros/src/lib.rs            |  8 ++----
 sqlx-macros/src/migrate.rs        |  1 -
 src/lib.rs                        |  4 ---
 src/macros.rs                     | 43 +++++++++++++++++++++++++++++++
 5 files changed, 46 insertions(+), 12 deletions(-)

diff --git a/sqlx-core/src/migrate/migrator.rs b/sqlx-core/src/migrate/migrator.rs
index 916a8df0..0ee4773d 100644
--- a/sqlx-core/src/migrate/migrator.rs
+++ b/sqlx-core/src/migrate/migrator.rs
@@ -37,7 +37,7 @@ impl Migrator {
     }
 
     /// Creates a new instance from a static slice of migrations.
-    pub async fn from_static(migrations: &'static [Migration]) -> Self {
+    pub fn from_static(migrations: &'static [Migration]) -> Self {
         Self {
             migrations: Cow::Borrowed(migrations),
         }
diff --git a/sqlx-macros/src/lib.rs b/sqlx-macros/src/lib.rs
index d1d64cec..7dc5c53e 100644
--- a/sqlx-macros/src/lib.rs
+++ b/sqlx-macros/src/lib.rs
@@ -87,12 +87,8 @@ pub fn derive_from_row(input: TokenStream) -> TokenStream {
 pub fn migrate(input: TokenStream) -> TokenStream {
     use syn::LitStr;
 
-    let input = syn::parse_macro_input!(input as Option<LitStr>);
-    let dir = input
-        .as_ref()
-        .map_or("migrations".to_owned(), LitStr::value);
-
-    match migrate::expand_migrator_from_dir(dir) {
+    let input = syn::parse_macro_input!(input as LitStr);
+    match migrate::expand_migrator_from_dir(input.value()) {
         Ok(ts) => ts.into(),
         Err(e) => {
             if let Some(parse_err) = e.downcast_ref::<syn::Error>() {
diff --git a/sqlx-macros/src/migrate.rs b/sqlx-macros/src/migrate.rs
index 1b1ac224..b0ebd0eb 100644
--- a/sqlx-macros/src/migrate.rs
+++ b/sqlx-macros/src/migrate.rs
@@ -2,7 +2,6 @@ use proc_macro2::TokenStream;
 use quote::{quote, ToTokens, TokenStreamExt};
 use sha2::{Digest, Sha384};
 use std::fs;
-use std::fs::DirEntry;
 use std::path::Path;
 
 struct QuotedMigration {
diff --git a/src/lib.rs b/src/lib.rs
index 53b01bd9..125342ba 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -61,10 +61,6 @@ pub extern crate sqlx_macros;
 #[doc(hidden)]
 pub use sqlx_macros::{FromRow, Type};
 
-// embedded migrations
-#[cfg(all(feature = "migrate", features = "macros"))]
-pub use sqlx_macros::migrate;
-
 #[cfg(feature = "macros")]
 mod macros;
 
diff --git a/src/macros.rs b/src/macros.rs
index 6cb4e635..574eee79 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -573,3 +573,46 @@ macro_rules! query_file_as_unchecked (
         macro_result!($($args),*)
     })
 );
+
+/// Creates a static [Migrator][crate::migrate::Migrator] by embedding the migrations in the binary.
+///
+/// The macro takes an optional migrations directory and defaults to `"migrations"` if it's not specified.
+///
+/// ```rust,ignore
+/// sqlx::migrate!("migrations") // same as sqlx::migrate!()
+///     .run(&pool)
+///     .await?;
+/// ```
+///
+/// It can also be used as a static constructor.
+///
+/// ```rust,ignore
+/// use sqlx::migrate::Migrator;
+///
+/// static MIGRATOR: Migrator = sqlx::migrate!();
+/// ```
+#[cfg(feature = "migrate")]
+#[macro_export]
+macro_rules! migrate {
+    ($dir:literal) => {
+        #[allow(dead_code)]
+        {
+            #[macro_use]
+            mod _macro_result {
+                $crate::sqlx_macros::migrate!($dir);
+            }
+            macro_result!()
+        }
+    };
+
+    () => {
+        #[allow(dead_code)]
+        {
+            #[macro_use]
+            mod _macro_result {
+                $crate::sqlx_macros::migrate!("migrations");
+            }
+            macro_result!()
+        }
+    };
+}