back to original

Author: DevinR528

clippy_lints/src/macro_use.rs

@@ -12,18 +12,28 @@ const PRELUDE: &[&str] = &[
     "marker", "ops", "convert", "iter", "option", "result", "borrow", "boxed", "string", "vec",
     "macros"
 ];
-
-pub struct ImportData {
+const BRACKETS: &[char] = &['<', '>'];
+/// MacroRefData includes the name of the macro
+/// and the path from `SourceMap::span_to_filename`.
+pub struct MacroRefData {
     name: String,
     path: String,
 }
 
-impl ImportData {
+impl MacroRefData {
     pub fn new(name: String, span: Span, ecx: &EarlyContext<'_>) -> Self {
-        let path = ecx.sess.source_map().span_to_filename(span);
-        let path = ecx.sess.source_map().span_to_unmapped_path(span);
-        println!("NEW {:?} {:?}", name, path);
-        Self { name: name.to_string(), path: path.to_string(), }
+        let mut path = ecx.sess.source_map().span_to_filename(span).to_string();
+
+        // std lib paths are <::std::module::file type>
+        // so remove brackets and space
+        if path.contains('<') {
+            path = path.replace(BRACKETS, "");
+        }
+        if path.contains(' ') {
+            path = path.split(' ').next().unwrap().to_string();
+        }
+        println!("NEW {} {}", name, path);
+        Self { name: name.to_string(), path, }
     }
 }
 
@@ -47,17 +57,47 @@ declare_clippy_lint! {
 
 #[derive(Default)]
 pub struct MacroUseImport {
+    /// the actual import path used and its span.
     imports: Vec<(String, Span)>,
-    collected: FxHashMap<Span, ImportData>,
+    /// the span of the macro reference and the `MacroRefData`
+    /// for the use of the macro.
+    collected: FxHashMap<Span, MacroRefData>,
 }
 
 impl MacroUseImport {
-    fn import_path_mac(&self, name: &str) -> String {
-        println!("END {:?}", name);
-        String::default() 
+    fn import_path_mac(&self, use_path: &str) -> String {
+        println!("END {:?}", use_path);
+
+        for mac in self.collected.values() {
+            if paths_match(mac, use_path) {
+                return make_path(mac, use_path)
+            }
+        }
+        format!("{}::<macro name>", use_path)
     }
 }
 
+fn paths_match(mac: &MacroRefData, use_path: &str) -> bool {
+    let segs = mac.path.split("::")
+        .filter(|s| *s == "")
+        .collect::<Vec<_>>();
+    if segs.starts_with(&["std"]) {
+        return PRELUDE.iter().any(|m| segs.contains(m))
+    }
+    false
+}
+
+fn make_path(mac: &MacroRefData, use_path: &str) -> String {
+    let mut res = String::default();
+    
+    let segs = mac.path.split("::")
+        .filter(|s| *s == "")
+        .collect::<Vec<_>>();
+    
+    
+    res
+}
+
 impl_lint_pass!(MacroUseImport => [MACRO_USE_IMPORT]);
 
 impl EarlyLintPass for MacroUseImport {
@@ -85,7 +125,7 @@ impl EarlyLintPass for MacroUseImport {
                 self.collected.entry(call_site)
                     .or_insert_with(|| {
                         println!("EXPR {:?}", name);
-                        ImportData::new(name.to_string(), callee.def_site, ecx)
+                        MacroRefData::new(name.to_string(), callee.def_site, ecx)
                     });
             }
         }
@@ -98,7 +138,7 @@ impl EarlyLintPass for MacroUseImport {
                 self.collected.entry(call_site)
                     .or_insert_with(|| {
                         println!("STMT {:?}", name);
-                        ImportData::new(name.to_string(), callee.def_site, ecx)
+                        MacroRefData::new(name.to_string(), callee.def_site, ecx)
                     });
             }
         }
@@ -111,7 +151,7 @@ impl EarlyLintPass for MacroUseImport {
                 self.collected.entry(call_site)
                     .or_insert_with(|| {
                         println!("PAT {:?}", name);
-                        ImportData::new(name.to_string(), callee.def_site, ecx)
+                        MacroRefData::new(name.to_string(), callee.def_site, ecx)
                     });
             }
         }
@@ -123,15 +163,16 @@ impl EarlyLintPass for MacroUseImport {
             self.collected.entry(call_site)
                 .or_insert_with(|| {
                     println!("MAC {:?}", name);
-                    ImportData::new(name.to_string(), callee.def_site, ecx)
+                    MacroRefData::new(name.to_string(), callee.def_site, ecx)
                 });
         }
     }
+
     fn check_crate_post(&mut self, ecx: &EarlyContext<'_>, krate: &ast::Crate) {
         for (name, span) in self.imports.iter() {
             let import_path = self.import_path_mac(&name);
             let msg = "`macro_use` attributes are no longer needed in the Rust 2018 edition";
-            let help = format!("use {}::{}", import_path, name);
+            let help = format!("use {}", import_path);
             span_lint_and_sugg(
                 ecx,
                 MACRO_USE_IMPORT,