document some more assists

4 files changed, 186 insertions, 6 deletions

diff --git a/crates/ra_assists/src/assists/merge_match_arms.rs b/crates/ra_assists/src/assists/merge_match_arms.rs
index 17baa98f9..f5ddd7159 100644
--- a/crates/ra_assists/src/assists/merge_match_arms.rs
+++ b/crates/ra_assists/src/assists/merge_match_arms.rs
@@ -1,9 +1,31 @@
-//! FIXME: write short doc here
-
 use crate::{Assist, AssistCtx, AssistId, TextRange, TextUnit};
 use hir::db::HirDatabase;
 use ra_syntax::ast::{AstNode, MatchArm};
 
+// Assist: merge_match_arms
+//
+// Merges identical match arms.
+//
+// ```
+// enum Action { Move { distance: u32 }, Stop }
+//
+// fn handle(action: Action) {
+//     match action {
+//         <|>Action::Move(..) => foo(),
+//         Action::Stop => foo(),
+//     }
+// }
+// ```
+// ->
+// ```
+// enum Action { Move { distance: u32 }, Stop }
+//
+// fn handle(action: Action) {
+//     match action {
+//         Action::Move(..) | Action::Stop => foo(),
+//     }
+// }
+// ```
 pub(crate) fn merge_match_arms(mut ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
     let current_arm = ctx.node_at_offset::<MatchArm>()?;
 
diff --git a/crates/ra_assists/src/assists/move_bounds.rs b/crates/ra_assists/src/assists/move_bounds.rs
index d2444b6b9..f96e19a9f 100644
--- a/crates/ra_assists/src/assists/move_bounds.rs
+++ b/crates/ra_assists/src/assists/move_bounds.rs
@@ -1,5 +1,3 @@
-//! FIXME: write short doc here
-
 use hir::db::HirDatabase;
 use ra_syntax::{
     ast::{self, edit, make, AstNode, NameOwner, TypeBoundsOwner},
@@ -9,6 +7,21 @@ use ra_syntax::{
 
 use crate::{Assist, AssistCtx, AssistId};
 
+// Assist: move_bounds_to_where_clause
+//
+// Moves inline type bounds to a where clause.
+//
+// ```
+// fn apply<T, U, <|>F: FnOnce(T) -> U>(f: F, x: T) -> U {
+//     f(x)
+// }
+// ```
+// ->
+// ```
+// fn apply<T, U, F>(f: F, x: T) -> U where F: FnOnce(T) -> U {
+//     f(x)
+// }
+// ```
 pub(crate) fn move_bounds_to_where_clause(mut ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
     let type_param_list = ctx.node_at_offset::<ast::TypeParamList>()?;
 
diff --git a/crates/ra_assists/src/assists/move_guard.rs b/crates/ra_assists/src/assists/move_guard.rs
index 51aea6334..36c95128d 100644
--- a/crates/ra_assists/src/assists/move_guard.rs
+++ b/crates/ra_assists/src/assists/move_guard.rs
@@ -1,5 +1,3 @@
-//! FIXME: write short doc here
-
 use hir::db::HirDatabase;
 use ra_syntax::{
     ast,
@@ -9,6 +7,31 @@ use ra_syntax::{
 
 use crate::{Assist, AssistCtx, AssistId};
 
+// Assist: move_guard_to_arm_body
+//
+// Moves match guard into match arm body.
+//
+// ```
+// enum Action { Move { distance: u32 }, Stop }
+//
+// fn handle(action: Action) {
+//     match action {
+//         Action::Move { distance } <|>if distance > 10 => foo(),
+//         _ => (),
+//     }
+// }
+// ```
+// ->
+// ```
+// enum Action { Move { distance: u32 }, Stop }
+//
+// fn handle(action: Action) {
+//     match action {
+//         Action::Move { distance } => if distance > 10 { foo() },
+//         _ => (),
+//     }
+// }
+// ```
 pub(crate) fn move_guard_to_arm_body(mut ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
     let match_arm = ctx.node_at_offset::<MatchArm>()?;
     let guard = match_arm.guard()?;
@@ -42,6 +65,31 @@ pub(crate) fn move_guard_to_arm_body(mut ctx: AssistCtx<impl HirDatabase>) -> Op
     ctx.build()
 }
 
+// Assist: move_arm_cond_to_match_guard
+//
+// Moves if expression from match arm body into a guard.
+//
+// ```
+// enum Action { Move { distance: u32 }, Stop }
+//
+// fn handle(action: Action) {
+//     match action {
+//         Action::Move { distance } => <|>if distance > 10 { foo() },
+//         _ => (),
+//     }
+// }
+// ```
+// ->
+// ```
+// enum Action { Move { distance: u32 }, Stop }
+//
+// fn handle(action: Action) {
+//     match action {
+//         Action::Move { distance } if distance > 10 => foo(),
+//         _ => (),
+//     }
+// }
+// ```
 pub(crate) fn move_arm_cond_to_match_guard(mut ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
     let match_arm: MatchArm = ctx.node_at_offset::<MatchArm>()?;
     let last_match_pat = match_arm.pats().last()?;
diff --git a/crates/ra_assists/src/doc_tests/generated.rs b/crates/ra_assists/src/doc_tests/generated.rs
index b96d5772e..09677af68 100644
--- a/crates/ra_assists/src/doc_tests/generated.rs
+++ b/crates/ra_assists/src/doc_tests/generated.rs
@@ -273,3 +273,100 @@ fn main() {
 "#####,
     )
 }
+
+#[test]
+fn doctest_merge_match_arms() {
+    check(
+        "merge_match_arms",
+        r#####"
+enum Action { Move { distance: u32 }, Stop }
+
+fn handle(action: Action) {
+    match action {
+        <|>Action::Move(..) => foo(),
+        Action::Stop => foo(),
+    }
+}
+"#####,
+        r#####"
+enum Action { Move { distance: u32 }, Stop }
+
+fn handle(action: Action) {
+    match action {
+        Action::Move(..) | Action::Stop => foo(),
+    }
+}
+"#####,
+    )
+}
+
+#[test]
+fn doctest_move_arm_cond_to_match_guard() {
+    check(
+        "move_arm_cond_to_match_guard",
+        r#####"
+enum Action { Move { distance: u32 }, Stop }
+
+fn handle(action: Action) {
+    match action {
+        Action::Move { distance } => <|>if distance > 10 { foo() },
+        _ => (),
+    }
+}
+"#####,
+        r#####"
+enum Action { Move { distance: u32 }, Stop }
+
+fn handle(action: Action) {
+    match action {
+        Action::Move { distance } if distance > 10 => foo(),
+        _ => (),
+    }
+}
+"#####,
+    )
+}
+
+#[test]
+fn doctest_move_bounds_to_where_clause() {
+    check(
+        "move_bounds_to_where_clause",
+        r#####"
+fn apply<T, U, <|>F: FnOnce(T) -> U>(f: F, x: T) -> U {
+    f(x)
+}
+"#####,
+        r#####"
+fn apply<T, U, F>(f: F, x: T) -> U where F: FnOnce(T) -> U {
+    f(x)
+}
+"#####,
+    )
+}
+
+#[test]
+fn doctest_move_guard_to_arm_body() {
+    check(
+        "move_guard_to_arm_body",
+        r#####"
+enum Action { Move { distance: u32 }, Stop }
+
+fn handle(action: Action) {
+    match action {
+        Action::Move { distance } <|>if distance > 10 => foo(),
+        _ => (),
+    }
+}
+"#####,
+        r#####"
+enum Action { Move { distance: u32 }, Stop }
+
+fn handle(action: Action) {
+    match action {
+        Action::Move { distance } => if distance > 10 { foo() },
+        _ => (),
+    }
+}
+"#####,
+    )
+}