Don't escape objective-c method names (#2648)

* Don't escape objective-c method names

* Still escape `crate`, `self`, and the like

* Don't escape keywords if they are method names

* Update tests

* Update CHANGELOG.md

CHANGELOG.md

@@ -186,6 +186,8 @@
 - Allow compiling `bindgen-cli` with a static libclang.
 - Emit an opaque integer type for pointer types that don't have the same size
   as the target's pointer size.
+- Avoid escaping Objective-C method names unless they are `Self`, `self`,
+  `crate` or `super`.
 ## Security
 
 # 0.68.1

bindgen-tests/tests/headers/objc_escape.h

@@ -5,3 +5,9 @@
 -(void)f:(int)arg1 as:(int)arg2;
 -(void)crate:(int)self;
 @end
+
+@interface B
+
+@property(nonatomic, retain) id type;
+
+@end

bindgen/ir/objc.rs

@@ -253,11 +253,24 @@ impl ObjCMethod {
         let split_name: Vec<Option<Ident>> = self
             .name
             .split(':')
-            .map(|name| {
+            .enumerate()
+            .map(|(idx, name)| {
                 if name.is_empty() {
                     None
+                } else if idx == 0 {
+                    // Try to parse the method name as an identifier. Having a keyword is ok
+                    // unless it is `crate`, `self`, `super` or `Self`, so we try to add the `_`
+                    // suffix to it and parse it.
+                    if ["crate", "self", "super", "Self"].contains(&name) {
+                        Some(Ident::new(
+                            &format!("{}_", name),
+                            Span::call_site(),
+                        ))
+                    } else {
+                        Some(Ident::new(name, Span::call_site()))
+                    }
                 } else {
-                    // Try to parse the current name as an identifier. This might fail if the name
+                    // Try to parse the current joining name as an identifier. This might fail if the name
                     // is a keyword, so we try to  "r#" to it and parse again, this could also fail
                     // if the name is `crate`, `self`, `super` or `Self`, so we try to add the `_`
                     // suffix to it and parse again. If this also fails, we panic with the first