[npm#5280] Detect default save, improve tests

workspaces/config/lib/index.js

@@ -233,8 +233,9 @@ class Config {
       this.#flatten(data, this.#flatOptions)
     }
 
-    // Ensure 'save' is true if a saveType has been specified
-    if (this.#flatOptions.saveType) {
+    // Only set 'save' to true if a saveType has been specified
+    // and if 'save' is false due to non-default config
+    if (!this.isDefault('save') && this.#flatOptions.saveType) {
       this.#flatOptions.save = true
     }
     this.#flatOptions.nodeBin = this.execPath

workspaces/config/test/index.js

@@ -910,48 +910,42 @@ t.test('finding the global prefix', t => {
 
 t.test('manages the save flag when flat is retrieved', t => {
   const npmPath = __dirname
-  t.test('does not set save to true if a save flag is not passed', async t => {
+  const buildConfig = async (args = [], envSave = false) => {
     const c = new Config({
-      argv: [process.execPath, __filename],
+      argv: [process.execPath, __filename, ...args],
       shorthands,
       definitions,
       npmPath,
       flatten,
+      env: {
+        save: envSave,
+      },
     })
     await c.load()
+    // Ensure test runner environment's npm settings do not change test outcomes
+    c.set('save', envSave, 'user')
+    c.set('save', envSave, 'global')
+    c.set('save', envSave, 'project')
+    return c
+  }
+  t.test('does not override save to true if a save flag is not passed', async t => {
+    const c = await buildConfig([], false)
     t.equal(c.flat.save, false)
   })
-  t.test('does not set save to true if flag is passed that does not efffect saveType', async t => {
-    const c = new Config({
-      argv: [process.execPath, __filename, '--save-exact'],
-      shorthands,
-      definitions,
-      npmPath,
-      flatten,
-    })
-    await c.load()
+  t.test('does not override save to true if a negative save flag is passed', async t => {
+    const c = await buildConfig(['--save-dev=false'], false)
     t.equal(c.flat.save, false)
   })
-  t.test('does not set save to true if a negative save flag is passed', async t => {
-    const c = new Config({
-      argv: [process.execPath, __filename, '--save-dev=false'],
-      shorthands,
-      definitions,
-      npmPath,
-      flatten,
-    })
-    await c.load()
+  t.test('overrides save to true if a save flag is passed', async t => {
+    const c = await buildConfig(['--save-prod'], false)
+    t.equal(c.flat.save, true)
+  })
+  t.test('does not overwrite save if --no-save is present', async t => {
+    const c = await buildConfig(['--no-save'], true)
     t.equal(c.flat.save, false)
   })
-  t.test('sets save to true if a save flag is passed', async t => {
-    const c = new Config({
-      argv: [process.execPath, __filename, '--save-prod'],
-      shorthands,
-      definitions,
-      npmPath,
-      flatten,
-    })
-    await c.load()
+  t.test('overwrites save if --no-save is present and also a save flag', async t => {
+    const c = await buildConfig(['--save-prod', '--no-save'], false)
     t.equal(c.flat.save, true)
   })
   t.end()