More strict macro check

src/utils.rs

@@ -14,40 +14,51 @@ pub const STRING_PATH: [&'static str; 3] = ["collections", "string", "String"];
 pub const VEC_PATH:    [&'static str; 3] = ["collections", "vec", "Vec"];
 pub const LL_PATH:     [&'static str; 3] = ["collections", "linked_list", "LinkedList"];
 
-/// returns true if the macro that expanded the crate was outside of
-/// the current crate or was a compiler plugin
-pub fn in_macro(cx: &Context, opt_info: Option<&ExpnInfo>) -> bool {
-    // no ExpnInfo = no macro
-    opt_info.map_or(false, |info| {
-        match info.callee.format {
-            ExpnFormat::CompilerExpansion(..) => {
-                if info.callee.name() == "closure expansion" {
-                    return false;
-                }
-            },
-            ExpnFormat::MacroAttribute(..) => {
-                // these are all plugins
-                return true;
-            },
-            _ => (),
+/// returns true this expn_info was expanded by any macro
+pub fn in_macro(cx: &Context, span: Span) -> bool {
+    cx.sess().codemap().with_expn_info(span.expn_id,
+            |info| info.map_or(false, |i| {
+        match i.callee.format {
+            ExpnFormat::CompilerExpansion(..) => false,
+            _ => true,
         }
-        // no span for the callee = external macro
-        info.callee.span.map_or(true, |span| {
-            // no snippet = external macro or compiler-builtin expansion
-            cx.sess().codemap().span_to_snippet(span).ok().map_or(true, |code|
-                // macro doesn't start with "macro_rules"
-                // = compiler plugin
-                !code.starts_with("macro_rules")
-            )
-        })
-    })
+    }))
 }
 
-/// invokes in_macro with the expansion info of the given span
-/// slightly heavy, try to use this after other checks have already happened
+/// returns true if the macro that expanded the crate was outside of
+/// the current crate or was a compiler plugin
 pub fn in_external_macro(cx: &Context, span: Span) -> bool {
+	/// invokes in_macro with the expansion info of the given span
+	/// slightly heavy, try to use this after other checks have already happened
+	fn in_macro_ext(cx: &Context, opt_info: Option<&ExpnInfo>) -> bool {
+		// no ExpnInfo = no macro
+		opt_info.map_or(false, |info| {
+			match info.callee.format {
+				ExpnFormat::CompilerExpansion(..) => {
+					if info.callee.name() == "closure expansion" {
+						return false;
+					}
+				},
+				ExpnFormat::MacroAttribute(..) => {
+					// these are all plugins
+					return true;
+				},
+				_ => (),
+			}
+			// no span for the callee = external macro
+			info.callee.span.map_or(true, |span| {
+				// no snippet = external macro or compiler-builtin expansion
+				cx.sess().codemap().span_to_snippet(span).ok().map_or(true, |code|
+					// macro doesn't start with "macro_rules"
+					// = compiler plugin
+					!code.starts_with("macro_rules")
+				)
+			})
+		})
+	}
+
     cx.sess().codemap().with_expn_info(span.expn_id,
-            |info| in_macro(cx, info))
+            |info| in_macro_ext(cx, info))
 }
 
 /// check if a DefId's path matches the given absolute type path