From 7ad55e976c3f88e92075379c8a4c1f413665b458 Mon Sep 17 00:00:00 2001
From: kjeremy <kjeremy@gmail.com>
Date: Wed, 30 Oct 2019 14:38:45 -0400
Subject: Document match_ast!

---
 crates/ra_syntax/src/lib.rs | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/crates/ra_syntax/src/lib.rs b/crates/ra_syntax/src/lib.rs
index c315ba552..5dcb6a95a 100644
--- a/crates/ra_syntax/src/lib.rs
+++ b/crates/ra_syntax/src/lib.rs
@@ -160,6 +160,20 @@ impl SourceFile {
     }
 }
 
+/// Matches a `SyntaxNode` against an `ast` type.
+///
+/// # Example:
+///
+/// ```ignore
+/// match_ast! {
+///     match node {
+///         ast::CallExpr(it) => { ... },
+///         ast::MethodCallExpr(it) => { ... },
+///         ast::MacroCall(it) => { ... },
+///         _ => None,
+///     }
+/// }
+/// ```
 #[macro_export]
 macro_rules! match_ast {
     (match $node:ident {
-- 
cgit v1.2.3


From 4d17658940ec73554dfef799b22e8829ab5ad61a Mon Sep 17 00:00:00 2001
From: kjeremy <kjeremy@gmail.com>
Date: Wed, 30 Oct 2019 14:39:05 -0400
Subject: Use match_ast! in FnCallNode::with_node

---
 crates/ra_ide_api/src/call_info.rs | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/crates/ra_ide_api/src/call_info.rs b/crates/ra_ide_api/src/call_info.rs
index e494f5620..3572825b5 100644
--- a/crates/ra_ide_api/src/call_info.rs
+++ b/crates/ra_ide_api/src/call_info.rs
@@ -4,7 +4,7 @@ use ra_db::SourceDatabase;
 use ra_syntax::{
     algo::ancestors_at_offset,
     ast::{self, ArgListOwner},
-    AstNode, SyntaxNode, TextUnit,
+    match_ast, AstNode, SyntaxNode, TextUnit,
 };
 use test_utils::tested_by;
 
@@ -91,14 +91,13 @@ enum FnCallNode {
 impl FnCallNode {
     fn with_node(syntax: &SyntaxNode, offset: TextUnit) -> Option<FnCallNode> {
         ancestors_at_offset(syntax, offset).find_map(|node| {
-            if let Some(expr) = ast::CallExpr::cast(node.clone()) {
-                Some(FnCallNode::CallExpr(expr))
-            } else if let Some(expr) = ast::MethodCallExpr::cast(node.clone()) {
-                Some(FnCallNode::MethodCallExpr(expr))
-            } else if let Some(expr) = ast::MacroCall::cast(node) {
-                Some(FnCallNode::MacroCallExpr(expr))
-            } else {
-                None
+            match_ast! {
+                match node {
+                    ast::CallExpr(it) => { Some(FnCallNode::CallExpr(it)) },
+                    ast::MethodCallExpr(it) => { Some(FnCallNode::MethodCallExpr(it)) },
+                    ast::MacroCall(it) => { Some(FnCallNode::MacroCallExpr(it)) },
+                    _ => { None },
+                }
             }
         })
     }
-- 
cgit v1.2.3