👍 show constraint error warning (#404)

* 👍 show constraint error warning

* 👍 simplify detecting the error message

* 🌿 clarify test issue

autoload/denops/_internal/server/proc.vim

@@ -96,6 +96,21 @@ function! s:on_exit(options, status) abort
   let s:job = v:null
   call denops#_internal#echo#debug(printf('Server stopped: %s', a:status))
   call denops#_internal#event#emit(printf('DenopsSystemProcessStopped:%s', a:status))
+  const l:last_error = execute('20messages')
+  if l:last_error =~# 'Could not find constraint\|Could not find version of'
+    " Show a warning message when Deno module cache issue is detected
+    " https://github.com/vim-denops/denops.vim/issues/358
+    call denops#_internal#echo#warn(repeat('*', 80))
+    call denops#_internal#echo#warn('Deno module cache issue is detected.')
+    call denops#_internal#echo#warn(
+          \ "Execute 'call denops#cache#update(#{reload: v:true})' and restart Vim/Neovim."
+          \ )
+    call denops#_internal#echo#warn(
+          \ 'See https://github.com/vim-denops/denops.vim/issues/358 for more detail.'
+          \ )
+    call denops#_internal#echo#warn(repeat('*', 80))
+    return
+  endif
   if s:job isnot# v:null || !a:options.restart_on_exit || s:stopped_on_purpose || s:exiting
     return
   endif

deno.jsonc

@@ -10,7 +10,8 @@
     "apply:supported-versions": "deno run --allow-read --allow-write .scripts/apply_supported_versions.ts"
   },
   "exclude": [
-    ".coverage/"
+    ".coverage/",
+    "tests/denops/testdata/no_check/"
   ],
   // NOTE: Import maps should only be used from test modules.
   "imports": {

tests/denops/runtime/functions/server_test.ts

@@ -3,7 +3,9 @@ import {
   assertEquals,
   assertFalse,
   assertMatch,
+  assertNotMatch,
   assertRejects,
+  assertStringIncludes,
 } from "jsr:@std/assert@^1.0.1";
 import { delay } from "jsr:@std/async@^0.224.0/delay";
 import { AsyncDisposableStack } from "jsr:@nick/dispose@^1.1.0/async-disposable-stack";
@@ -489,6 +491,56 @@ testHost({
         );
       });
     });
+
+    await t.step(
+      "if the server is stopped with a constraint error (issue 401)",
+      async (t) => {
+        await using stack = new AsyncDisposableStack();
+        stack.defer(async () => {
+          await host.call("denops#server#stop");
+          await wait(
+            () => host.call("eval", "denops#server#status() ==# 'stopped'"),
+          );
+        });
+
+        outputs = [];
+        await host.call("execute", [
+          "silent! unlet g:__test_denops_process_stopped_fired",
+          `let g:denops#server#deno_args = ['${
+            resolve("no_check/cli_constraint_error_on_issue_401.ts")
+          }']`,
+          "let g:denops#server#restart_delay = 1000",
+          "let g:denops#server#restart_interval = 10000",
+          "let g:denops#server#restart_threshold = 1",
+          "call denops#server#start()",
+        ], "");
+
+        await t.step("fires DenopsProcessStopped", async () => {
+          await wait(() =>
+            host.call("exists", "g:__test_denops_process_stopped_fired")
+          );
+        });
+
+        await t.step("changes status to 'stopped' asynchronously", async () => {
+          assertEquals(await host.call("denops#server#status"), "stopped");
+        });
+
+        await t.step("outputs warning message", async () => {
+          await delay(MESSAGE_DELAY);
+          assertStringIncludes(
+            outputs.join(""),
+            "Execute 'call denops#cache#update(#{reload: v:true})' and restart Vim/Neovim.",
+          );
+        });
+
+        await t.step("does not restart the server", () => {
+          assertNotMatch(
+            outputs.join(""),
+            /Server stopped.*Restarting/,
+          );
+        });
+      },
+    );
   },
 });
 
@@ -1275,3 +1327,8 @@ testHost({
     });
   },
 });
+
+/** Resolve testdata script URL. */
+function resolve(path: string): string {
+  return new URL(`../../testdata/${path}`, import.meta.url).href;
+}

tests/denops/testdata/no_check/cli_constraint_error_on_issue_401.ts

@@ -0,0 +1 @@
+import * as _ from "jsr:@std/async@1.0.0-constraint-error";