Unified: Handle Swift default with an ignore pattern

Author: paldepind

unified/extractor/ast_types.yml

@@ -387,10 +387,10 @@ named:
 
   # A single `case ...:` (or `default:`) entry in a switch.
   # An entry with multiple `case p1, p2:` patterns uses an `or_pattern`.
-  # A `default:` entry has no pattern.
+  # A `default:` entry uses an `ignore_pattern`.
   switch_case:
     modifier*: modifier
-    pattern?: expr
+    pattern: expr
     body: block
 
   # Evaluate 'expr' and match its result against 'pattern', and return true if it matches.

unified/extractor/src/languages/swift/swift.rs

@@ -918,7 +918,7 @@ fn translation_rules() -> Vec<Rule<SwiftContext>> {
         ),
         // A `switch` statement. Each `switchCase` becomes a `switch_case` with a
         // pattern (or an `or_pattern` for comma-separated `case a, b:`) and a
-        // body; a `default:` case has a body but no pattern. The case items and
+        // body; a `default:` case uses an `ignore_pattern`. The case items and
         // body are auto-translated; the Rust block only picks the pattern shape
         // by arity (the query engine can't branch on list length).
         rule!(
@@ -934,9 +934,11 @@ fn translation_rules() -> Vec<Rule<SwiftContext>> {
                 body: (block stmt: {body}))
         ),
         rule!(
-            (switchCase label: (switchDefaultLabel) statements: _* @body)
+            (switchCase label: (switchDefaultLabel defaultKeyword: @@keyword) statements: _* @body)
             =>
-            (switch_case body: (block stmt: {body}))
+            (switch_case
+                pattern: (ignore_pattern #{keyword})
+                body: (block stmt: {body}))
         ),
         // A single case item unwraps to its pattern, possibly boxed in conditional_pattern
         rule!(

unified/extractor/tests/corpus/swift/control-flow/binding-modifier-does-not-leak-to-sibling.output

@@ -105,7 +105,8 @@ top_level source="⟨body⟩"
                       argument:
                         argument source="⟨value⟩"
                           value: string_literal "\"matched\"" source="\"matched\""
-            switch_case source="default:\n  ⟨body⟩"
+            switch_case source="⟨pattern⟩:\n  ⟨body⟩"
+              pattern: ignore_pattern "default" source="default"
               body:
                 block source="⟨stmt⟩"
                   stmt: break_expr "break" source="break"

unified/extractor/tests/corpus/swift/control-flow/fallthrough.output

@@ -104,7 +104,8 @@ top_level source="⟨body⟩"
                       body:
                         block source="⟨stmt⟩"
                           stmt: unsupported_node "fallthrough" source="fallthrough"
-                    switch_case source="default:\n    ⟨body⟩"
+                    switch_case source="⟨pattern⟩:\n    ⟨body⟩"
+                      pattern: ignore_pattern "default" source="default"
                       body:
                         block source="⟨stmt⟩"
                           stmt: break_expr "break" source="break"

unified/extractor/tests/corpus/swift/control-flow/nested-enum-case-pattern.output

@@ -286,7 +286,8 @@ top_level source="⟨body⟩"
               body:
                 block source="⟨stmt⟩"
                   stmt: break_expr "break" source="break"
-            switch_case source="default:\n  ⟨body⟩"
+            switch_case source="⟨pattern⟩:\n  ⟨body⟩"
+              pattern: ignore_pattern "default" source="default"
               body:
                 block source="⟨stmt⟩"
                   stmt: break_expr "break" source="break"

unified/extractor/tests/corpus/swift/control-flow/switch-case-item-where-clauses.output

@@ -200,7 +200,8 @@ top_level source="⟨body⟩"
                       argument:
                         argument source="⟨value⟩"
                           value: string_literal "\"non-positive\"" source="\"non-positive\""
-            switch_case source="default:\n  ⟨body⟩"
+            switch_case source="⟨pattern⟩:\n  ⟨body⟩"
+              pattern: ignore_pattern "default" source="default"
               body:
                 block source="⟨stmt⟩"
                   stmt:

unified/extractor/tests/corpus/swift/control-flow/switch-expression-pattern.output

@@ -393,7 +393,8 @@ top_level source="⟨body⟩"
                       argument:
                         argument source="⟨value⟩"
                           value: identifier "fallback" source="fallback"
-            switch_case source="default:\n    ⟨body⟩"
+            switch_case source="⟨pattern⟩:\n    ⟨body⟩"
+              pattern: ignore_pattern "default" source="default"
               body:
                 block source="⟨stmt⟩"
                   stmt: break_expr "break" source="break"

unified/extractor/tests/corpus/swift/control-flow/switch-statement.output

@@ -151,7 +151,8 @@ top_level source="⟨body⟩"
                       argument:
                         argument source="⟨value⟩"
                           value: string_literal "\"two or three\"" source="\"two or three\""
-            switch_case source="default:\n  ⟨body⟩"
+            switch_case source="⟨pattern⟩:\n  ⟨body⟩"
+              pattern: ignore_pattern "default" source="default"
               body:
                 block source="⟨stmt⟩"
                   stmt:

unified/extractor/tests/corpus/swift/types/binding-modifier-does-not-leak-into-accessor-body.output

@@ -114,7 +114,8 @@ top_level source="var p: Int {\n  ⟨body⟩\n}"
                           stmt:
                             return_expr source="return ⟨value⟩"
                               value: int_literal "1" source="1"
-                    switch_case source="default:\n      ⟨body⟩"
+                    switch_case source="⟨pattern⟩:\n      ⟨body⟩"
+                      pattern: ignore_pattern "default" source="default"
                       body:
                         block source="⟨stmt⟩"
                           stmt:

unified/extractor/tests/corpus/swift/variables/binding-modifier-does-not-leak-into-initializer.output

@@ -77,7 +77,8 @@ top_level source="⟨body⟩"
                   body:
                     block source="⟨stmt⟩"
                       stmt: int_literal "1" source="1"
-                switch_case source="default: ⟨body⟩"
+                switch_case source="⟨pattern⟩: ⟨body⟩"
+                  pattern: ignore_pattern "default" source="default"
                   body:
                     block source="⟨stmt⟩"
                       stmt: int_literal "2" source="2"