Combine if and unless guard conditions

Shopify · Oct 24, 2024 · 72f946e · 72f946e
1 parent fb82456
commit 72f946e
Showing 1 changed file with 16 additions and 17 deletions.
diff --git a/parser/prism/Translator.cc b/parser/prism/Translator.cc
@@ -1347,30 +1347,29 @@ unique_ptr<parser::Node> Translator::patternTranslate(pm_node_t *node) {
             auto inlineIfSingle = true;
             auto statements = translateStatements(inNode->statements, inlineIfSingle);
 
-            if (prismPattern != nullptr && PM_NODE_TYPE_P(prismPattern, PM_IF_NODE)) {
-                auto ifNode = reinterpret_cast<pm_if_node *>(prismPattern);
-                auto prismStatements = reinterpret_cast<pm_statements_node *>(ifNode->statements);
-
-                if (prismStatements->body.size != 1) {
-                    unreachable("In pattern-matching's `in` clause, an `if` guard must have a single statement.");
+            if (prismPattern != nullptr &&
+                (PM_NODE_TYPE_P(prismPattern, PM_IF_NODE) || PM_NODE_TYPE_P(prismPattern, PM_UNLESS_NODE))) {
+                pm_statements_node *prismStatements = nullptr;
+                unique_ptr<parser::Node> sorbetGuard;
+
+                if (PM_NODE_TYPE_P(prismPattern, PM_IF_NODE)) {
+                    auto ifNode = down_cast<pm_if_node>(prismPattern);
+                    prismStatements = ifNode->statements;
+                    sorbetGuard = make_unique<parser::IfGuard>(location, translate(ifNode->predicate));
+                } else { // PM_UNLESS_NODE
+                    auto unlessNode = down_cast<pm_unless_node>(prismPattern);
+                    prismStatements = unlessNode->statements;
+                    sorbetGuard = make_unique<parser::UnlessGuard>(location, translate(unlessNode->predicate));
                 }
 
-                auto sorbetPattern = patternTranslate(prismStatements->body.nodes[0]);
-                auto sorbetGuard = make_unique<parser::IfGuard>(location, translate(ifNode->predicate));
-
-                return make_unique<parser::InPattern>(location, move(sorbetPattern), move(sorbetGuard), move(statements));
-            } else if (prismPattern != nullptr && PM_NODE_TYPE_P(prismPattern, PM_UNLESS_NODE)) {
-                auto unlessNode = reinterpret_cast<pm_unless_node *>(prismPattern);
-                auto prismStatements = reinterpret_cast<pm_statements_node *>(unlessNode->statements);
-
                 if (prismStatements->body.size != 1) {
-                    unreachable("In pattern-matching's `in` clause, an `unless` guard must have a single statement.");
+                    unreachable("In pattern-matching's `in` clause, a guard must have a single statement.");
                 }
 
                 auto sorbetPattern = patternTranslate(prismStatements->body.nodes[0]);
-                auto sorbetGuard = make_unique<parser::UnlessGuard>(location, translate(unlessNode->predicate));
 
-                return make_unique<parser::InPattern>(location, move(sorbetPattern), move(sorbetGuard), move(statements));
+                return make_unique<parser::InPattern>(location, move(sorbetPattern), move(sorbetGuard),
+                                                      move(statements));
             } else {
                 auto sorbetPattern = patternTranslate(prismPattern);