Merge main

scripts/generate-ts7-ast-schema.mjs

@@ -282,6 +282,26 @@ const adaptedGetters = new Set([
   "operand",
   "questionToken",
 ]);
+// A getter selects its child's wire slot by kind directly: an integer
+// switch, without astChildOrder's switch on the child's name. `answer`
+// maps a slot to the returned expression; `missing` is returned for kinds
+// without the child.
+const slotCases = (name, answer, missing) => {
+  const kindsBySlot = new Map();
+  for (const [kind, childNames] of Object.entries(protocol.childProperties)) {
+    const slot = childNames.indexOf(name);
+    if (slot < 0) continue;
+    if (!kindsBySlot.has(slot)) kindsBySlot.set(slot, []);
+    kindsBySlot.get(slot).push(kind);
+  }
+  const lines = ["    switch (this.kind) {"];
+  for (const [slot, kinds] of [...kindsBySlot].sort((a, b) => a[0] - b[0])) {
+    for (const kind of kinds) lines.push(`      case ${kind}:`);
+    lines.push(`        return ${answer(slot)};`);
+  }
+  lines.push("      default:", `        return ${missing};`, "    }");
+  return lines.join("\n");
+};
 const getters = names
   .filter((name) => !adaptedGetters.has(name))
   .map((name) => {
@@ -292,12 +312,19 @@ const getters = names
       .replaceAll("RemoteNode", "AstNode");
     const method =
       type.includes("AstNode |") && type.includes("AstNodeList")
-        ? "child"
+        ? "childAt"
         : type.includes("AstNodeList")
-          ? "childList"
-          : "childNode";
-    return `  get ${name}(): ${type} {\n    return this.${method}(${JSON.stringify(name)});\n  }`;
+          ? "childListAt"
+          : "childNodeAt";
+    return `  get ${name}(): ${type} {\n${slotCases(name, (slot) => `this.${method}(${slot})`, "undefined")}\n  }`;
   });
+// The adapted getters read their raw child through the same slot switch.
+const adaptedSlots = [...adaptedGetters]
+  .sort()
+  .map(
+    (name) =>
+      `  private ${name}Slot(): number {\n${slotCases(name, (slot) => String(slot), "-1")}\n  }`,
+  );
 const nodeTarget = join(root, "packages/compiler/src/frontend/ts7/ast-node.ts");
 const before = readFileSync(nodeTarget, "utf8");
 if (
@@ -311,6 +338,7 @@ const after = before.replace(
     "  // BEGIN GENERATED CHILD GETTERS",
     `  // Generated from typescript@${version}; run scripts/generate-ts7-ast-schema.mjs.`,
     ...getters,
+    ...adaptedSlots,
     "  // END GENERATED CHILD GETTERS",
   ].join("\n"),
 );