remove UnsupportedPattern variant in mono patterns

compiler/gen/tests/gen_primitives.rs

@@ -1786,4 +1786,21 @@ mod gen_primitives {
             i64
         );
     }
+
+    #[test]
+    #[ignore]
+    #[should_panic(expected = "")]
+    fn unsupported_pattern_str_interp() {
+        assert_evals_to!(
+            indoc!(
+                r#"
+                { x: 4 } = { x : 4 }
+
+                x
+                "#
+            ),
+            0,
+            i64
+        );
+    }
 }

compiler/gen/tests/helpers/eval.rs

@@ -64,11 +64,14 @@ pub fn helper<'a>(
     debug_assert_eq!(exposed_to_host.len(), 1);
     let main_fn_symbol = exposed_to_host.keys().copied().nth(0).unwrap();
 
-    let (_, main_fn_layout) = procedures
-        .keys()
-        .find(|(s, _)| *s == main_fn_symbol)
-        .unwrap()
-        .clone();
+    let (_, main_fn_layout) = match procedures.keys().find(|(s, _)| *s == main_fn_symbol) {
+        Some(found) => found.clone(),
+        None => panic!(
+            "The main function symbol {:?} does not have a procedure in {:?}",
+            main_fn_symbol,
+            &procedures.keys()
+        ),
+    };
 
     let target = target_lexicon::Triple::host();
     let ptr_bytes = target.pointer_width().unwrap().bytes() as u32;

compiler/mono/src/decision_tree.rs

@@ -379,7 +379,7 @@ fn test_at_path<'a>(selected_path: &Path, branch: &Branch<'a>, all_tests: &mut V
 
             match pattern {
                 // TODO use guard!
-                Identifier(_) | Underscore | UnsupportedPattern(_) => {
+                Identifier(_) | Underscore => {
                     if let Guard::Guard { symbol, id, stmt } = guard {
                         all_tests.push(Guarded {
                             opt_test: None,
@@ -531,7 +531,7 @@ fn to_relevant_branch_help<'a>(
     use Test::*;
 
     match pattern {
-        Identifier(_) | Underscore | UnsupportedPattern(_) => Some(branch.clone()),
+        Identifier(_) | Underscore => Some(branch.clone()),
 
         RecordDestructure(destructs, _) => match test {
             IsCtor {
@@ -742,7 +742,7 @@ fn needs_tests<'a>(pattern: &Pattern<'a>) -> bool {
     use Pattern::*;
 
     match pattern {
-        Identifier(_) | Underscore | UnsupportedPattern(_) => false,
+        Identifier(_) | Underscore => false,
 
         RecordDestructure(_, _)
         | AppliedTag { .. }

compiler/mono/src/exhaustive.rs

@@ -84,12 +84,6 @@ fn simplify<'a>(pattern: &crate::ir::Pattern<'a>) -> Pattern {
             Ctor(union, tag_id, patterns)
         }
 
-        UnsupportedPattern(_region) => {
-            // Treat as an Anything
-            // code-gen will make a runtime error out of the branch
-            Anything
-        }
-
         AppliedTag {
             tag_id,
             arguments,

compiler/mono/src/ir.rs

@@ -4699,10 +4699,6 @@ fn store_pattern<'a>(
         RecordDestructure(_, _) => {
             unreachable!("a record destructure must always occur on a struct layout");
         }
-
-        UnsupportedPattern(_region) => {
-            return Err(&"unsupported pattern");
-        }
     }
 
     Ok(stmt)
@@ -5466,11 +5462,6 @@ pub enum Pattern<'a> {
         layout: Layout<'a>,
         union: crate::exhaustive::Union,
     },
-
-    // Runtime Exceptions
-    // Shadowed(Region, Located<Ident>),
-    // Example: (5 = 1 + 2) is an unsupported pattern in an assignment; Int patterns aren't allowed in assignments!
-    UnsupportedPattern(Region),
 }
 
 #[derive(Clone, Debug, PartialEq)]
@@ -5512,10 +5503,11 @@ pub fn from_can_pattern<'a>(
             original_region: *region,
             shadow: ident.clone(),
         }),
-        UnsupportedPattern(region) => Ok(Pattern::UnsupportedPattern(*region)),
+        UnsupportedPattern(region) => Err(RuntimeError::UnsupportedPattern(*region)),
+
         MalformedPattern(_problem, region) => {
             // TODO preserve malformed problem information here?
-            Ok(Pattern::UnsupportedPattern(*region))
+            Err(RuntimeError::UnsupportedPattern(*region))
         }
         NumLiteral(var, num) => match num_argument_to_int_or_float(env.subs, *var) {
             IntOrFloat::IntType => Ok(Pattern::IntLiteral(*num)),