fix: resolveNets.ts diagnostic error handling

cli/resolveNets.ts

@@ -3,21 +3,52 @@ import { register } from "../deps/shims/register-ts-node.ts"
 import * as path from "../deps/std/path.ts"
 import { NetSpec } from "../nets/mod.ts"
 
+const TS_MODULE_HAS_NO_EXPORTED_MEMBER = 2305
+const TS_CANNOT_FIND_MODULE_OR_ITS_CORRESPONDING_TYPE_DECLARATIONS = 2307
+
 const $nets = $.record($.instance(NetSpec as new() => NetSpec, $.tuple(), (_: NetSpec) => []))
+const $tsDiagnostics = $.field("diagnosticCodes", $.array($.u32))
 
 export async function resolveNets(maybeNetsPath?: string): Promise<Record<string, NetSpec>> {
   const resolvedNetsPath = await resolveNetsPath(maybeNetsPath)
   if (resolvedNetsPath.endsWith(".ts")) {
     await register()
   }
   // shimmed by dnt
-  let nets = await _import(resolvedNetsPath)
+  let nets = await importNets(resolvedNetsPath)
   if ("default" in nets) nets = nets.default
   $.assert($nets, nets)
   for (const key in nets) nets[key]!.name = key
   return nets
 }
 
+async function importNets(netsPath: string) {
+  try {
+    return await _import(netsPath)
+  } catch (err) {
+    let errorMessage = `Failed to import nets file ${netsPath}.`
+    if ($.is($tsDiagnostics, err)) {
+      for (const code of new Set(err.diagnosticCodes)) {
+        errorMessage += ` Typescript compiler error TS${code}.`
+        switch (code) {
+          case TS_MODULE_HAS_NO_EXPORTED_MEMBER:
+            errorMessage += " Did you import from \"capi/nets\"?"
+            break
+          case TS_CANNOT_FIND_MODULE_OR_ITS_CORRESPONDING_TYPE_DECLARATIONS:
+            errorMessage +=
+              " Did you set your tsconfig module to \"ESNext\" and moduleResolution to \"node16\"?"
+            break
+          default:
+            break
+        }
+      }
+    } else {
+      console.error(err)
+    }
+    throw new Error(errorMessage)
+  }
+}
+
 async function resolveNetsPath(maybeNetsPath?: string): Promise<string> {
   if (maybeNetsPath) return path.resolve(maybeNetsPath)
   for (const p of ["nets.ts", "nets.js"]) {