Generate typed QX bindings and add source editing tools

src/capability-language/source-loader.ts

@@ -0,0 +1,77 @@
+import { lstat, readFile } from "node:fs/promises";
+import path from "node:path";
+import { parseQx, validateQxImportPath, walkSyntax } from "./source.js";
+
+export const readQxSource = async (root: string, name: string) => {
+  validateQxImportPath(name);
+  let current = path.resolve(root);
+  const segments = name.split("/");
+  for (const [index, segment] of segments.entries()) {
+    current = path.join(current, segment);
+    const stat = await lstat(current);
+    if (stat.isSymbolicLink() || (index === segments.length - 1 ? !stat.isFile() : !stat.isDirectory()))
+      throw new Error(`QX imports must be ordinary files beneath ordinary directories: ${name}`);
+  }
+  return readFile(current, "utf8");
+};
+
+/** Local imports share one workspace scope; paths are always repository-relative. */
+export const resolveQxSources = async (
+  read: (name: string) => Promise<string>, entry = "workspace.qx",
+) => {
+  const files = new Map<string, string>();
+  const active: string[] = [];
+  const visited = new Set<string>();
+  const segments: { start: number; end: number; fileName: string; sourceStart: number }[] = [];
+  let source = "";
+  const append = (fileName: string, text: string, sourceStart: number) => {
+    segments.push({ start: source.length, end: source.length + text.length, fileName, sourceStart });
+    source += text;
+  };
+  const visit = async (name: string, root: boolean) => {
+    validateQxImportPath(name);
+    if (active.includes(name)) throw new Error(`QX import cycle: ${[...active, name].join(" -> ")}`);
+    if (visited.has(name)) return;
+    const text = await read(name);
+    const syntax = parseQx(text, name);
+    if (syntax.diagnostics.length) throw new Error(syntax.diagnostics.map((d) =>
+      `${name}:${d.line}:${d.column + 1}: ${d.message}`).join("\n"));
+    const declaration = syntax.root.children[0]!;
+    if (declaration.kind !== (root ? "workspaceDecl" : "fragmentDecl"))
+      throw new Error(`${name}: expected ${root ? "workspace" : "fragment"} document`);
+    files.set(name, text);
+    active.push(name);
+    visited.add(name);
+    const braces = syntax.tokens.filter((token) => !token.trivia);
+    let cursor = root ? 0 : braces.find((token) => token.kind === "LBRACE")!.end;
+    const end = root ? text.length : braces.filter((token) => token.kind === "RBRACE").at(-1)!.start;
+    for (const node of walkSyntax(declaration)) {
+      if (node.kind !== "sourceImportDecl") continue;
+      append(name, text.slice(cursor, node.start), cursor);
+      const literal = node.children.find((child) => child.kind === "stringLiteral")!;
+      // Separators prevent adjacent tokens/comments joining across files.
+      append(name, "\n", node.start);
+      await visit(JSON.parse(text.slice(literal.start, literal.end)), false);
+      append(name, "\n", node.end);
+      cursor = node.end;
+    }
+    append(name, text.slice(cursor, end), cursor);
+    active.pop();
+  };
+  await visit(entry, true);
+  return {
+    source, sourceFiles: [...files.keys()], files,
+    originalPosition(line: number, column: number) {
+      const lines = source.split("\n");
+      const offset = lines.slice(0, line - 1).reduce((sum, value) => sum + value.length + 1, 0) +
+        [...(lines[line - 1] ?? "")].slice(0, column).join("").length;
+      const segment = segments.find((entry) => entry.start <= offset && entry.end > offset);
+      if (!segment) return { fileName: entry, line, column };
+      const prefix = files.get(segment.fileName)!.slice(0, segment.sourceStart + offset - segment.start);
+      return { fileName: segment.fileName, line: prefix.split("\n").length,
+        column: prefix.length - prefix.lastIndexOf("\n") - 1 };
+    },
+  };
+};
+
+export const loadQxSources = (root: string) => resolveQxSources((name) => readQxSource(root, name));