1 files changed, 59 insertions, 1 deletions

diff --git a/crates/ra_hir_ty/src/infer.rs b/crates/ra_hir_ty/src/infer.rs
index bd4ef69a0..a21ad8d86 100644
--- a/crates/ra_hir_ty/src/infer.rs
+++ b/crates/ra_hir_ty/src/infer.rs
@@ -210,6 +210,13 @@ struct InferenceContext<'a> {
     /// closures, but currently this is the only field that will change there,
     /// so it doesn't make sense.
     return_ty: Ty,
+    diverges: Diverges,
+    breakables: Vec<BreakableContext>,
+}
+
+#[derive(Clone, Debug)]
+struct BreakableContext {
+    pub may_break: bool,
 }
 
 impl<'a> InferenceContext<'a> {
@@ -224,6 +231,8 @@ impl<'a> InferenceContext<'a> {
             owner,
             body: db.body(owner),
             resolver,
+            diverges: Diverges::Maybe,
+            breakables: Vec::new(),
         }
     }
 
@@ -666,15 +675,57 @@ impl Expectation {
     }
 }
 
+#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
+enum Diverges {
+    Maybe,
+    Always,
+}
+
+impl Diverges {
+    fn is_always(self) -> bool {
+        self == Diverges::Always
+    }
+}
+
+impl std::ops::BitAnd for Diverges {
+    type Output = Self;
+    fn bitand(self, other: Self) -> Self {
+        std::cmp::min(self, other)
+    }
+}
+
+impl std::ops::BitOr for Diverges {
+    type Output = Self;
+    fn bitor(self, other: Self) -> Self {
+        std::cmp::max(self, other)
+    }
+}
+
+impl std::ops::BitAndAssign for Diverges {
+    fn bitand_assign(&mut self, other: Self) {
+        *self = *self & other;
+    }
+}
+
+impl std::ops::BitOrAssign for Diverges {
+    fn bitor_assign(&mut self, other: Self) {
+        *self = *self | other;
+    }
+}
+
 mod diagnostics {
     use hir_def::{expr::ExprId, FunctionId};
     use hir_expand::diagnostics::DiagnosticSink;
 
-    use crate::{db::HirDatabase, diagnostics::NoSuchField};
+    use crate::{
+        db::HirDatabase,
+        diagnostics::{BreakOutsideOfLoop, NoSuchField},
+    };
 
     #[derive(Debug, PartialEq, Eq, Clone)]
     pub(super) enum InferenceDiagnostic {
         NoSuchField { expr: ExprId, field: usize },
+        BreakOutsideOfLoop { expr: ExprId },
     }
 
     impl InferenceDiagnostic {
@@ -690,6 +741,13 @@ mod diagnostics {
                     let field = source_map.field_syntax(*expr, *field);
                     sink.push(NoSuchField { file: field.file_id, field: field.value })
                 }
+                InferenceDiagnostic::BreakOutsideOfLoop { expr } => {
+                    let (_, source_map) = db.body_with_source_map(owner.into());
+                    let ptr = source_map
+                        .expr_syntax(*expr)
+                        .expect("break outside of loop in synthetic syntax");
+                    sink.push(BreakOutsideOfLoop { file: ptr.file_id, expr: ptr.value })
+                }
             }
         }
     }