Fix FP in `default_numeric_fallback` with external macro expansion

4 files changed, 69 insertions, 26 deletions

diff --git a/clippy_lints/src/default_numeric_fallback.rs b/clippy_lints/src/default_numeric_fallback.rs
index 759f7d4062d..a125376bffa 100644
--- a/clippy_lints/src/default_numeric_fallback.rs
+++ b/clippy_lints/src/default_numeric_fallback.rs
@@ -7,9 +7,10 @@ use rustc_hir::{
     intravisit::{walk_expr, walk_stmt, NestedVisitorMap, Visitor},
     Body, Expr, ExprKind, HirId, Lit, Stmt, StmtKind,
 };
-use rustc_lint::{LateContext, LateLintPass};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::{
     hir::map::Map,
+    lint::in_external_macro,
     ty::{self, FloatTy, IntTy, PolyFnSig, Ty},
 };
 use rustc_session::{declare_lint_pass, declare_tool_lint};
@@ -73,6 +74,7 @@ impl<'a, 'tcx> NumericFallbackVisitor<'a, 'tcx> {
     /// Check whether a passed literal has potential to cause fallback or not.
     fn check_lit(&self, lit: &Lit, lit_ty: Ty<'tcx>) {
         if_chain! {
+                if !in_external_macro(self.cx.sess(), lit.span);
                 if let Some(ty_bound) = self.ty_bounds.last();
                 if matches!(lit.node,
                             LitKind::Int(_, LitIntType::Unsuffixed) | LitKind::Float(_, LitFloatType::Unsuffixed));
diff --git a/tests/ui/auxiliary/macro_rules.rs b/tests/ui/auxiliary/macro_rules.rs
index d4470d3f407..170955e726c 100644
--- a/tests/ui/auxiliary/macro_rules.rs
+++ b/tests/ui/auxiliary/macro_rules.rs
@@ -106,3 +106,10 @@ macro_rules! field_reassign_with_default {
         }
     };
 }
+
+#[macro_export]
+macro_rules! default_numeric_fallback {
+    () => {
+        let x = 22;
+    };
+}
diff --git a/tests/ui/default_numeric_fallback.rs b/tests/ui/default_numeric_fallback.rs
index 43468872db0..c0625fd1b75 100644
--- a/tests/ui/default_numeric_fallback.rs
+++ b/tests/ui/default_numeric_fallback.rs
@@ -1,3 +1,5 @@
+// aux-build:macro_rules.rs
+
 #![warn(clippy::default_numeric_fallback)]
 #![allow(unused)]
 #![allow(clippy::never_loop)]
@@ -5,6 +7,9 @@
 #![allow(clippy::unnecessary_operation)]
 #![allow(clippy::branches_sharing_code)]
 
+#[macro_use]
+extern crate macro_rules;
+
 mod basic_expr {
     fn test() {
         // Should lint unsuffixed literals typed `i32`.
@@ -133,4 +138,22 @@ mod method_calls {
     }
 }
 
+mod in_macro {
+    macro_rules! internal_macro {
+        () => {
+            let x = 22;
+        };
+    }
+
+    // Should lint in internal macro.
+    fn internal() {
+        internal_macro!();
+    }
+
+    // Should NOT lint in external macro.
+    fn external() {
+        default_numeric_fallback!();
+    }
+}
+
 fn main() {}
diff --git a/tests/ui/default_numeric_fallback.stderr b/tests/ui/default_numeric_fallback.stderr
index d1c4c8203dd..5862cd936ac 100644
--- a/tests/ui/default_numeric_fallback.stderr
+++ b/tests/ui/default_numeric_fallback.stderr
@@ -1,5 +1,5 @@
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:11:17
+  --> $DIR/default_numeric_fallback.rs:16:17
    |
 LL |         let x = 22;
    |                 ^^ help: consider adding suffix: `22_i32`
@@ -7,142 +7,153 @@ LL |         let x = 22;
    = note: `-D clippy::default-numeric-fallback` implied by `-D warnings`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:12:18
+  --> $DIR/default_numeric_fallback.rs:17:18
    |
 LL |         let x = [1, 2, 3];
    |                  ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:12:21
+  --> $DIR/default_numeric_fallback.rs:17:21
    |
 LL |         let x = [1, 2, 3];
    |                     ^ help: consider adding suffix: `2_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:12:24
+  --> $DIR/default_numeric_fallback.rs:17:24
    |
 LL |         let x = [1, 2, 3];
    |                        ^ help: consider adding suffix: `3_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:13:28
+  --> $DIR/default_numeric_fallback.rs:18:28
    |
 LL |         let x = if true { (1, 2) } else { (3, 4) };
    |                            ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:13:31
+  --> $DIR/default_numeric_fallback.rs:18:31
    |
 LL |         let x = if true { (1, 2) } else { (3, 4) };
    |                               ^ help: consider adding suffix: `2_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:13:44
+  --> $DIR/default_numeric_fallback.rs:18:44
    |
 LL |         let x = if true { (1, 2) } else { (3, 4) };
    |                                            ^ help: consider adding suffix: `3_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:13:47
+  --> $DIR/default_numeric_fallback.rs:18:47
    |
 LL |         let x = if true { (1, 2) } else { (3, 4) };
    |                                               ^ help: consider adding suffix: `4_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:14:23
+  --> $DIR/default_numeric_fallback.rs:19:23
    |
 LL |         let x = match 1 {
    |                       ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:15:13
+  --> $DIR/default_numeric_fallback.rs:20:13
    |
 LL |             1 => 1,
    |             ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:15:18
+  --> $DIR/default_numeric_fallback.rs:20:18
    |
 LL |             1 => 1,
    |                  ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:16:18
+  --> $DIR/default_numeric_fallback.rs:21:18
    |
 LL |             _ => 2,
    |                  ^ help: consider adding suffix: `2_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:20:17
+  --> $DIR/default_numeric_fallback.rs:25:17
    |
 LL |         let x = 0.12;
    |                 ^^^^ help: consider adding suffix: `0.12_f64`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:38:21
+  --> $DIR/default_numeric_fallback.rs:43:21
    |
 LL |             let y = 1;
    |                     ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:46:21
+  --> $DIR/default_numeric_fallback.rs:51:21
    |
 LL |             let y = 1;
    |                     ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:52:21
+  --> $DIR/default_numeric_fallback.rs:57:21
    |
 LL |             let y = 1;
    |                     ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:64:9
+  --> $DIR/default_numeric_fallback.rs:69:9
    |
 LL |         1
    |         ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:70:27
+  --> $DIR/default_numeric_fallback.rs:75:27
    |
 LL |         let f = || -> _ { 1 };
    |                           ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:74:29
+  --> $DIR/default_numeric_fallback.rs:79:29
    |
 LL |         let f = || -> i32 { 1 };
    |                             ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:88:21
+  --> $DIR/default_numeric_fallback.rs:93:21
    |
 LL |         generic_arg(1);
    |                     ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:91:32
+  --> $DIR/default_numeric_fallback.rs:96:32
    |
 LL |         let x: _ = generic_arg(1);
    |                                ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:109:28
+  --> $DIR/default_numeric_fallback.rs:114:28
    |
 LL |         GenericStruct { x: 1 };
    |                            ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:112:36
+  --> $DIR/default_numeric_fallback.rs:117:36
    |
 LL |         let _ = GenericStruct { x: 1 };
    |                                    ^ help: consider adding suffix: `1_i32`
 
 error: default numeric fallback might occur
-  --> $DIR/default_numeric_fallback.rs:132:23
+  --> $DIR/default_numeric_fallback.rs:137:23
    |
 LL |         s.generic_arg(1);
    |                       ^ help: consider adding suffix: `1_i32`
 
-error: aborting due to 24 previous errors
+error: default numeric fallback might occur
+  --> $DIR/default_numeric_fallback.rs:144:21
+   |
+LL |             let x = 22;
+   |                     ^^ help: consider adding suffix: `22_i32`
+...
+LL |         internal_macro!();
+   |         ------------------ in this macro invocation
+   |
+   = note: this error originates in the macro `internal_macro` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: aborting due to 25 previous errors