Method execute

src/tools/filesystem/multi-file-edit.ts:97–184

(args: z.infer<typeof MultiFileEditArgs>, _ctx: ToolContext)

  argsSchema = MultiFileEditArgs;

  async execute(args: z.infer<typeof MultiFileEditArgs>, _ctx: ToolContext): Promise<ToolResult> {
    const plans: EditPlan[] = [];
    const failures: string[] = [];

    // PASS 1: validate every file/edit without writing
    for (const file of args.files) {
      try {
        const plan = await planFile(file.path, file.edits);
        plans.push(plan);
      } catch (e: any) {
        failures.push(e?.message ?? String(e));
      }
    }

    if (failures.length > 0) {
      return {
        content: `[MULTI_EDIT_REJECTED] Validation failed; NO files were modified:\n` +
          failures.map(f => '  - ' + f).join('\n'),
        isError: true,
      };
    }

    if (args.dry_run) {
      const summary = plans.map(p => {
        const changedLines = countChangedLines(p.originalContent, p.finalContent);
        return `  ${p.path}  (${p.editCount} edit${p.editCount > 1 ? 's' : ''}, ${changedLines} line${changedLines !== 1 ? 's' : ''} would change)`;
      });
      return {
        content: `Dry run — ${plans.length} file(s) would be modified:\n${summary.join('\n')}\n\n` +
          `Re-run with dry_run=false to apply.`,
      };
    }

    // PASS 1.5: syntax-gate every final content BEFORE any write (this tool
    // bypasses Transaction.write, so it runs the same gate explicitly).
    // All-or-nothing is preserved: one syntactically broken plan rejects the batch.
    {
      const { checkSyntaxForWrite } = await import('../ast/syntax-check.js');
      const syntaxFailures: string[] = [];
      for (const plan of plans) {
        if (!plan.changed) continue;
        const rejection = await checkSyntaxForWrite(plan.path, plan.originalContent, plan.finalContent);
        if (rejection) syntaxFailures.push(rejection);
      }
      if (syntaxFailures.length > 0) {
        return {
          content: `[MULTI_EDIT_REJECTED] Syntax validation failed; NO files were modified:\n` +
            syntaxFailures.map(f => '  - ' + f).join('\n'),
          isError: true,
        };
      }
    }

    // PASS 2: write all the files
    // We do NOT have transaction integration here yet (that would touch the
    // transaction journal); for v0.9.2 we do sequential writes and report any
    // partial failure clearly. Full transaction integration in v1.0.0.
    const written: string[] = [];