From 9de6beeae28841d7a8b6bc06d6b66a30c723939d Mon Sep 17 00:00:00 2001
From: Kevyn Grasso <kevgrasso@gmail.com>
Date: Mon, 12 Nov 2018 15:50:27 -0500
Subject: [PATCH] debug logging, added conditional error message, tests updated

---
 src/librustc_resolve/lib.rs          | 19 ++++++++++++++++---
 src/test/ui/error-codes/E0424.rs     |  1 +
 src/test/ui/error-codes/E0424.stderr |  8 +++++++-
 3 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index ebd2c87fa4642..e449fece6b474 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -3010,6 +3010,7 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> {
         // Visit all direct subpatterns of this pattern.
         let outer_pat_id = pat.id;
         pat.walk(&mut |pat| {
+            debug!("resolve_pattern pat={:?} node={:?}", pat, pat.node);
             match pat.node {
                 PatKind::Ident(bmode, ident, ref opt_pat) => {
                     // First try to resolve the identifier as some existing
@@ -3166,6 +3167,7 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> {
                  format!("not found in {}", mod_str),
                  item_span)
             };
+
             let code = DiagnosticId::Error(code.into());
             let mut err = this.session.struct_span_err_with_code(base_span, &base_msg, code);
 
@@ -3189,11 +3191,22 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> {
                 return (err, Vec::new());
             }
             if is_self_value(path, ns) {
+                debug!("smart_resolve_path_fragment E0424 source:{:?}", source);
+
                 __diagnostic_used!(E0424);
                 err.code(DiagnosticId::Error("E0424".into()));
-                err.span_label(span, format!("`self` value is a keyword \
-                                               only available in \
-                                               methods with `self` parameter"));
+                err.span_label(span, match source {
+                    PathSource::Pat => {
+                        format!("`self` value is a keyword \
+                                and may not be bound to \
+                                variables or shadowed")
+                    }
+                    _ => {
+                        format!("`self` value is a keyword \
+                                only available in methods \
+                                with `self` parameter")
+                    }
+                });
                 return (err, Vec::new());
             }
 
diff --git a/src/test/ui/error-codes/E0424.rs b/src/test/ui/error-codes/E0424.rs
index 445d0c5f3edc0..20d42da1c0c40 100644
--- a/src/test/ui/error-codes/E0424.rs
+++ b/src/test/ui/error-codes/E0424.rs
@@ -19,4 +19,5 @@ impl Foo {
 }
 
 fn main () {
+    let self = "self"; //~ ERROR E0424
 }
diff --git a/src/test/ui/error-codes/E0424.stderr b/src/test/ui/error-codes/E0424.stderr
index a1b7a5f65336f..5eccd7d2283fe 100644
--- a/src/test/ui/error-codes/E0424.stderr
+++ b/src/test/ui/error-codes/E0424.stderr
@@ -4,6 +4,12 @@ error[E0424]: expected value, found module `self`
 LL |         self.bar(); //~ ERROR E0424
    |         ^^^^ `self` value is a keyword only available in methods with `self` parameter
 
-error: aborting due to previous error
+error[E0424]: expected unit struct/variant or constant, found module `self`
+  --> $DIR/E0424.rs:22:9
+   |
+LL |     let self = "self"; //~ ERROR E0424
+   |         ^^^^ `self` value is a keyword and may not be bound to variables or shadowed
+
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0424`.