Infra: extract backup and plugin path helpers

src/infra/plugin-install-path-warnings.ts

@@ -0,0 +1,73 @@
+import fs from "node:fs/promises";
+import path from "node:path";
+import type { PluginInstallRecord } from "../config/types.plugins.js";
+
+export type PluginInstallPathIssue = {
+  kind: "custom-path" | "missing-path";
+  pluginId: string;
+  path: string;
+};
+
+function resolvePluginInstallCandidatePaths(
+  install: PluginInstallRecord | null | undefined,
+): string[] {
+  if (!install || install.source !== "path") {
+    return [];
+  }
+
+  return [install.sourcePath, install.installPath]
+    .map((value) => (typeof value === "string" ? value.trim() : ""))
+    .filter(Boolean);
+}
+
+export async function detectPluginInstallPathIssue(params: {
+  pluginId: string;
+  install: PluginInstallRecord | null | undefined;
+}): Promise<PluginInstallPathIssue | null> {
+  const candidatePaths = resolvePluginInstallCandidatePaths(params.install);
+  if (candidatePaths.length === 0) {
+    return null;
+  }
+
+  for (const candidatePath of candidatePaths) {
+    try {
+      await fs.access(path.resolve(candidatePath));
+      return {
+        kind: "custom-path",
+        pluginId: params.pluginId,
+        path: candidatePath,
+      };
+    } catch {
+      // Keep checking remaining candidate paths before warning about a stale install.
+    }
+  }
+
+  return {
+    kind: "missing-path",
+    pluginId: params.pluginId,
+    path: candidatePaths[0] ?? "(unknown)",
+  };
+}
+
+export function formatPluginInstallPathIssue(params: {
+  issue: PluginInstallPathIssue;
+  pluginLabel: string;
+  defaultInstallCommand: string;
+  repoInstallCommand: string;
+  formatCommand?: (command: string) => string;
+}): string[] {
+  const formatCommand = params.formatCommand ?? ((command: string) => command);
+  if (params.issue.kind === "custom-path") {
+    return [
+      `${params.pluginLabel} is installed from a custom path: ${params.issue.path}`,
+      `Main updates will not automatically replace that plugin with the repo's default ${params.pluginLabel} package.`,
+      `Reinstall with "${formatCommand(params.defaultInstallCommand)}" when you want to return to the standard ${params.pluginLabel} plugin.`,
+      `If you are intentionally running from a repo checkout, reinstall that checkout explicitly with "${formatCommand(params.repoInstallCommand)}" after updates.`,
+    ];
+  }
+  return [
+    `${params.pluginLabel} is installed from a custom path that no longer exists: ${params.issue.path}`,
+    `Reinstall with "${formatCommand(params.defaultInstallCommand)}".`,
+    `If you are running from a repo checkout, you can also use "${formatCommand(params.repoInstallCommand)}".`,
+  ];
+}