From ef9ad490a0f391dee05f4d779b0c33c3f6412ed2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E7=8E=8B=E8=83=9C?= <2318857637@qq.com>
Date: Sat, 13 Jun 2026 13:45:12 +0800
Subject: [PATCH] fix: avoid conflicting prefer config flags

---
 lib/fetcher.js                         | 4 ++--
 tap-snapshots/test/fetcher.js.test.cjs | 4 ----
 test/fetcher.js                        | 8 ++++++++
 3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/lib/fetcher.js b/lib/fetcher.js
index 20c0d675..3cdcd188 100644
--- a/lib/fetcher.js
+++ b/lib/fetcher.js
@@ -104,8 +104,8 @@ class FetcherBase {
     // a dist-tag, but certainly wants to keep defaulting to latest.
     this.npmCliConfig = opts.npmCliConfig || [
       `--cache=${dirname(this.cache)}`,
-      `--prefer-offline=${!!this.preferOffline}`,
-      `--prefer-online=${!!this.preferOnline}`,
+      ...(this.preferOffline ? ['--prefer-offline=true'] : []),
+      ...(this.preferOnline ? ['--prefer-online=true'] : []),
       `--offline=${!!this.offline}`,
       ...(this.before ? [`--before=${this.before.toISOString()}`] : []),
       '--no-progress',
diff --git a/tap-snapshots/test/fetcher.js.test.cjs b/tap-snapshots/test/fetcher.js.test.cjs
index d79d6957..de4976aa 100644
--- a/tap-snapshots/test/fetcher.js.test.cjs
+++ b/tap-snapshots/test/fetcher.js.test.cjs
@@ -37,8 +37,6 @@ Array [
 exports[`test/fetcher.js TAP snapshot the npmInstallCmd and npmInstallConfig > default install config 1`] = `
 Array [
   "--cache={CACHE}",
-  "--prefer-offline=false",
-  "--prefer-online=false",
   "--offline=false",
   "--no-progress",
   "--no-save",
@@ -55,8 +53,6 @@ Array [
 exports[`test/fetcher.js TAP snapshot the npmInstallCmd and npmInstallConfig > default install config with before 1`] = `
 Array [
   "--cache={CACHE}",
-  "--prefer-offline=false",
-  "--prefer-online=false",
   "--offline=false",
   "--before=1979-07-01T19:10:00.000Z",
   "--no-progress",
diff --git a/test/fetcher.js b/test/fetcher.js
index 7cc8b52d..1421e574 100644
--- a/test/fetcher.js
+++ b/test/fetcher.js
@@ -69,6 +69,14 @@ t.test('snapshot the npmInstallCmd and npmInstallConfig', async t => {
     'do not have a _cacache folder on cache config passed to npm cli')
   t.equal(basename(def.cache), '_cacache',
     'have a _cacache folder on default pacote config itself')
+  t.not(def.npmCliConfig.includes('--prefer-offline=false'), 'does not pass disabled prefer-offline')
+  t.not(def.npmCliConfig.includes('--prefer-online=false'), 'does not pass disabled prefer-online')
+  const preferOffline = new FileFetcher(abbrevspec, { preferOffline: true })
+  t.ok(preferOffline.npmCliConfig.includes('--prefer-offline=true'), 'passes prefer-offline when enabled')
+  t.not(preferOffline.npmCliConfig.includes('--prefer-online=true'), 'does not pass prefer-online with prefer-offline')
+  const preferOnline = new FileFetcher(abbrevspec, { preferOnline: true })
+  t.ok(preferOnline.npmCliConfig.includes('--prefer-online=true'), 'passes prefer-online when enabled')
+  t.not(preferOnline.npmCliConfig.includes('--prefer-offline=true'), 'does not pass prefer-offline with prefer-online')
   const bef = new FileFetcher(abbrevspec, {
     before: new Date('1979-07-01T19:10:00.000Z'),
   })