unified: Add or_pattern and fix 'if case let' translation

unified/extractor/ast_types.yml

@@ -42,6 +42,7 @@ supertypes:
     - name_pattern
     - tuple_pattern
     - constructor_pattern
+    - or_pattern
     - ignore_pattern
     - expr_equality_pattern
     - bulk_importing_pattern
@@ -359,12 +360,12 @@ named:
     case*: switch_case
 
   # A single `case ...:` (or `default:`) entry in a switch.
-  # An entry with multiple `case p1, p2:` patterns has multiple `pattern`s.
-  # A `default:` entry has no patterns.
+  # An entry with multiple `case p1, p2:` patterns uses an `or_pattern`.
+  # A `default:` entry has no pattern.
   # An optional `guard` corresponds to a `where`-clause on the case.
   switch_case:
     modifier*: modifier
-    pattern*: pattern
+    pattern?: pattern
     guard?: expr
     body: block
 
@@ -421,6 +422,11 @@ named:
     constructor: expr_or_type
     element*: pattern_element
 
+  # A disjunction pattern that matches if any of its sub-patterns match.
+  or_pattern:
+    modifier*: modifier
+    pattern*: pattern
+
   # A pattern with an optional associated name.
   pattern_element:
     modifier*: modifier

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

@@ -652,25 +652,34 @@ fn translation_rules() -> Vec<Rule<SwiftContext>> {
             =>
             (switch_expr value: {val} case: {..cases})
         ),
-        // Switch entry with patterns and body
+        // Switch entry with multiple patterns and body
         rule!(
-            (switch_entry pattern: (switch_pattern pattern: @pats)* statement: _* @body)
+            (switch_entry
+                pattern: (switch_pattern pattern: @first)
+                pattern: (switch_pattern pattern: @rest)+
+                statement: _* @body)
             =>
-            (switch_case pattern: {..pats} body: (block stmt: {..body}))
+            (switch_case pattern: (or_pattern pattern: {first} pattern: {..rest}) body: (block stmt: {..body}))
+        ),
+        // Switch entry with exactly one pattern and body
+        rule!(
+            (switch_entry pattern: (switch_pattern pattern: @pat) statement: _* @body)
+            =>
+            (switch_case pattern: {pat} body: (block stmt: {..body}))
         ),
         // Switch entry: default case (no patterns)
         rule!(
             (switch_entry default: (default_keyword) statement: _* @body)
             =>
             (switch_case body: (block stmt: {..body}))
         ),
-        // if case let x = expr — the pattern is taken as-is (no Optional wrapping)
+        // if case PATTERN = expr — preserve the pattern directly (no Optional wrapping)
         rule!(
-            (if_let_binding "case" (value_binding_pattern) bound_identifier: @name _ @val)
+            (if_let_binding "case" pattern: @pat value: @val)
             =>
             (pattern_guard_expr
                 value: {val}
-                pattern: (name_pattern identifier: (identifier #{name})))
+                pattern: {pat})
         ),
         rule!(
             (if_let_binding

unified/extractor/tests/corpus/swift/control-flow.txt

@@ -573,10 +573,12 @@ top_level
                         name_expr
                           identifier: identifier "print"
               pattern:
-                expr_equality_pattern
-                  expr: int_literal "2"
-                expr_equality_pattern
-                  expr: int_literal "3"
+                or_pattern
+                  pattern:
+                    expr_equality_pattern
+                      expr: int_literal "2"
+                    expr_equality_pattern
+                      expr: int_literal "3"
             switch_case
               body:
                 block
@@ -592,6 +594,83 @@ top_level
             name_expr
               identifier: identifier "x"
 
+===
+If-case-let with shadowing in condition value
+===
+
+if case let x = x + 10 {
+  print(x)
+}
+
+---
+
+source_file
+  statement:
+    if_statement
+      body:
+        block
+          statement:
+            call_expression
+              function: simple_identifier "print"
+              suffix:
+                call_suffix
+                  arguments:
+                    value_arguments
+                      argument:
+                        value_argument
+                          value: simple_identifier "x"
+      condition:
+        if_condition
+          kind:
+            if_let_binding
+              pattern:
+                pattern
+                  kind:
+                    binding_pattern
+                      binding:
+                        value_binding_pattern
+                          mutability: let
+                      pattern:
+                        pattern
+                          bound_identifier: simple_identifier "x"
+              value:
+                additive_expression
+                  lhs: simple_identifier "x"
+                  op: +
+                  rhs: integer_literal "10"
+
+---
+
+top_level
+  body:
+    block
+      stmt:
+        if_expr
+          condition:
+            pattern_guard_expr
+              pattern:
+                name_pattern
+                  identifier: identifier "x"
+              value:
+                binary_expr
+                  operator: infix_operator "+"
+                  left:
+                    name_expr
+                      identifier: identifier "x"
+                  right: int_literal "10"
+          then:
+            block
+              stmt:
+                call_expr
+                  argument:
+                    argument
+                      value:
+                        name_expr
+                          identifier: identifier "x"
+                  callee:
+                    name_expr
+                      identifier: identifier "print"
+
 ===
 Switch with binding pattern
 ===

unified/ql/lib/codeql/unified/Ast.qll

@@ -978,6 +978,23 @@
     }
   }
 
+  /** A class representing `or_pattern` nodes. */
+  class OrPattern extends @unified_or_pattern, AstNode {
+    /** Gets the name of the primary QL class for this element. */
+    final override string getAPrimaryQlClass() { result = "OrPattern" }
+
+    /** Gets the node corresponding to the field `modifier`. */
+    final Modifier getModifier(int i) { unified_or_pattern_modifier(this, i, result) }
+
+    /** Gets the node corresponding to the field `pattern`. */
+    final Pattern getPattern(int i) { unified_or_pattern_pattern(this, i, result) }
+
+    /** Gets a field or child node of this node. */
+    final override AstNode getAFieldOrChild() {
+      unified_or_pattern_modifier(this, _, result) or unified_or_pattern_pattern(this, _, result)
+    }
+  }
+
   /** A class representing `parameter` nodes. */
   class Parameter extends @unified_parameter, AstNode {
     /** Gets the name of the primary QL class for this element. */
@@ -1109,14 +1126,14 @@
     final Modifier getModifier(int i) { unified_switch_case_modifier(this, i, result) }
 
     /** Gets the node corresponding to the field `pattern`. */
-    final Pattern getPattern(int i) { unified_switch_case_pattern(this, i, result) }
+    final Pattern getPattern() { unified_switch_case_pattern(this, result) }
 
     /** Gets a field or child node of this node. */
     final override AstNode getAFieldOrChild() {
       unified_switch_case_def(this, result) or
       unified_switch_case_guard(this, result) or
       unified_switch_case_modifier(this, _, result) or
-      unified_switch_case_pattern(this, _, result)
+      unified_switch_case_pattern(this, result)
     }
   }
 
@@ -1654,6 +1671,10 @@
       i = -1 and
       name = "getPrecedence"
       or
+      result = node.(OrPattern).getModifier(i) and name = "getModifier"
+      or
+      result = node.(OrPattern).getPattern(i) and name = "getPattern"
+      or
       result = node.(Parameter).getDefault() and i = -1 and name = "getDefault"
       or
       result = node.(Parameter).getExternalName() and i = -1 and name = "getExternalName"
@@ -1682,7 +1703,7 @@
       or
       result = node.(SwitchCase).getModifier(i) and name = "getModifier"
       or
-      result = node.(SwitchCase).getPattern(i) and name = "getPattern"
+      result = node.(SwitchCase).getPattern() and i = -1 and name = "getPattern"
       or
       result = node.(SwitchExpr).getCase(i) and name = "getCase"
       or

unified/ql/lib/unified.dbscheme

@@ -716,6 +716,24 @@ unified_operator_syntax_declaration_def(
   int name: @unified_token_identifier ref
 );
 
+#keyset[unified_or_pattern, index]
+unified_or_pattern_modifier(
+  int unified_or_pattern: @unified_or_pattern ref,
+  int index: int ref,
+  unique int modifier: @unified_token_modifier ref
+);
+
+#keyset[unified_or_pattern, index]
+unified_or_pattern_pattern(
+  int unified_or_pattern: @unified_or_pattern ref,
+  int index: int ref,
+  unique int pattern: @unified_pattern ref
+);
+
+unified_or_pattern_def(
+  unique int id: @unified_or_pattern
+);
+
 unified_parameter_default(
   unique int unified_parameter: @unified_parameter ref,
   unique int default: @unified_expr ref
@@ -747,7 +765,7 @@ unified_parameter_def(
   unique int id: @unified_parameter
 );
 
-@unified_pattern = @unified_bulk_importing_pattern | @unified_constructor_pattern | @unified_expr_equality_pattern | @unified_name_pattern | @unified_token_ignore_pattern | @unified_token_unsupported_node | @unified_tuple_pattern
+@unified_pattern = @unified_bulk_importing_pattern | @unified_constructor_pattern | @unified_expr_equality_pattern | @unified_name_pattern | @unified_or_pattern | @unified_token_ignore_pattern | @unified_token_unsupported_node | @unified_tuple_pattern
 
 unified_pattern_element_key(
   unique int unified_pattern_element: @unified_pattern_element ref,
@@ -795,10 +813,8 @@ unified_switch_case_modifier(
   unique int modifier: @unified_token_modifier ref
 );
 
-#keyset[unified_switch_case, index]
 unified_switch_case_pattern(
-  int unified_switch_case: @unified_switch_case ref,
-  int index: int ref,
+  unique int unified_switch_case: @unified_switch_case ref,
   unique int pattern: @unified_pattern ref
 );
 
@@ -1056,7 +1072,7 @@ unified_trivia_tokeninfo(
   string value: string ref
 );
 
-@unified_ast_node = @unified_accessor_declaration | @unified_argument | @unified_array_literal | @unified_assign_expr | @unified_associated_type_declaration | @unified_base_type | @unified_binary_expr | @unified_block | @unified_bound_type_constraint | @unified_break_expr | @unified_bulk_importing_pattern | @unified_call_expr | @unified_catch_clause | @unified_class_like_declaration | @unified_compound_assign_expr | @unified_constructor_declaration | @unified_constructor_pattern | @unified_continue_expr | @unified_destructor_declaration | @unified_do_while_stmt | @unified_equality_type_constraint | @unified_expr_equality_pattern | @unified_for_each_stmt | @unified_function_declaration | @unified_function_expr | @unified_function_type_expr | @unified_generic_type_expr | @unified_guard_if_stmt | @unified_if_expr | @unified_import_declaration | @unified_initializer_declaration | @unified_key_value_pair | @unified_labeled_stmt | @unified_map_literal | @unified_member_access_expr | @unified_name_expr | @unified_name_pattern | @unified_named_type_expr | @unified_operator_syntax_declaration | @unified_parameter | @unified_pattern_element | @unified_pattern_guard_expr | @unified_return_expr | @unified_switch_case | @unified_switch_expr | @unified_throw_expr | @unified_token | @unified_top_level | @unified_trivia_token | @unified_try_expr | @unified_tuple_expr | @unified_tuple_pattern | @unified_tuple_type_element | @unified_tuple_type_expr | @unified_type_alias_declaration | @unified_type_cast_expr | @unified_type_parameter | @unified_type_test_expr | @unified_type_test_pattern | @unified_unary_expr | @unified_variable_declaration | @unified_while_stmt
+@unified_ast_node = @unified_accessor_declaration | @unified_argument | @unified_array_literal | @unified_assign_expr | @unified_associated_type_declaration | @unified_base_type | @unified_binary_expr | @unified_block | @unified_bound_type_constraint | @unified_break_expr | @unified_bulk_importing_pattern | @unified_call_expr | @unified_catch_clause | @unified_class_like_declaration | @unified_compound_assign_expr | @unified_constructor_declaration | @unified_constructor_pattern | @unified_continue_expr | @unified_destructor_declaration | @unified_do_while_stmt | @unified_equality_type_constraint | @unified_expr_equality_pattern | @unified_for_each_stmt | @unified_function_declaration | @unified_function_expr | @unified_function_type_expr | @unified_generic_type_expr | @unified_guard_if_stmt | @unified_if_expr | @unified_import_declaration | @unified_initializer_declaration | @unified_key_value_pair | @unified_labeled_stmt | @unified_map_literal | @unified_member_access_expr | @unified_name_expr | @unified_name_pattern | @unified_named_type_expr | @unified_operator_syntax_declaration | @unified_or_pattern | @unified_parameter | @unified_pattern_element | @unified_pattern_guard_expr | @unified_return_expr | @unified_switch_case | @unified_switch_expr | @unified_throw_expr | @unified_token | @unified_top_level | @unified_trivia_token | @unified_try_expr | @unified_tuple_expr | @unified_tuple_pattern | @unified_tuple_type_element | @unified_tuple_type_expr | @unified_type_alias_declaration | @unified_type_cast_expr | @unified_type_parameter | @unified_type_test_expr | @unified_type_test_pattern | @unified_unary_expr | @unified_variable_declaration | @unified_while_stmt
 
 unified_ast_node_location(
   unique int node: @unified_ast_node ref,