From b0aa89749da04eee43fb69b557c16fb38f61a47b Mon Sep 17 00:00:00 2001
From: Huanyi Xie <74809554+xiehuanyi@users.noreply.github.com>
Date: Tue, 6 Oct 2026 22:04:34 +0300
Subject: [PATCH 1/2] fix: strip dashed keys at nested option paths

---
 lib/yargs-parser.ts   | 13 +++++++++++--
 test/yargs-parser.mjs | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/lib/yargs-parser.ts b/lib/yargs-parser.ts
index 48a2d0f2..7560b813 100644
--- a/lib/yargs-parser.ts
+++ b/lib/yargs-parser.ts
@@ -429,8 +429,17 @@ export class YargsParser {
     })
 
     if (configuration['camel-case-expansion'] && configuration['strip-dashed']) {
-      Object.keys(argv).filter(key => key !== '--' && key.includes('-')).forEach(key => {
-        delete argv[key]
+      const keys = new Set([...Object.keys(argv), ...Object.keys(flags.aliases)])
+      keys.forEach(key => {
+        if (key === '--' || !key.includes('-')) return
+        const parts = configuration['dot-notation'] ? key.split('.') : [key]
+        let target = argv
+        for (const part of parts.slice(0, -1)) {
+          const property = sanitizeKey(part)
+          if (!target || typeof target !== 'object' || !Object.prototype.hasOwnProperty.call(target, property)) return
+          target = target[property]
+        }
+        if (target && typeof target === 'object') delete target[sanitizeKey(parts[parts.length - 1])]
       })
     }
 
diff --git a/test/yargs-parser.mjs b/test/yargs-parser.mjs
index 4c692375..5c659dca 100644
--- a/test/yargs-parser.mjs
+++ b/test/yargs-parser.mjs
@@ -14,6 +14,39 @@ const require = createRequire(import.meta.url);
 should()
 
 describe('yargs-parser', function () {
+  it('strips dashed option keys at nested paths', function () {
+    const result = parser('--outer.inner-dash true --outer.deep.third-dash 5', {
+      configuration: { 'strip-dashed': true }
+    })
+    expect(result.outer).to.deep.equal({ innerDash: 'true', deep: { thirdDash: 5 } })
+  })
+
+  it('strips nested dashed configuration keys while retaining camel aliases', function () {
+    const result = parser([], {
+      configObjects: [{ outer: { 'inner-dash': 'value' } }],
+      configuration: { 'strip-dashed': true }
+    })
+    expect(result.outer).to.deep.equal({ innerDash: 'value' })
+  })
+
+  it('keeps literal dotted camel aliases when dot notation is disabled', function () {
+    const result = parser('--outer.inner-dash value', {
+      configuration: { 'strip-dashed': true, 'dot-notation': false }
+    })
+    expect(result['outer.innerDash']).to.equal('value')
+    expect(result).not.to.have.property('outer.inner-dash')
+  })
+
+  it('does not strip arbitrary keys from a coerced option object', function () {
+    const value = { 'literal-key': 'value' }
+    const result = parser('--option value', {
+      coerce: { option: () => value },
+      configuration: { 'strip-dashed': true }
+    })
+    expect(result.option).to.equal(value)
+    expect(result.option['literal-key']).to.equal('value')
+  })
+
   it('should parse a "short boolean"', function () {
     const parse = parser(['-b'])
     parse.should.not.have.property('--')

From 3ec58fbfb4695cbba4e7e47ca9fe3faaa10b914d Mon Sep 17 00:00:00 2001
From: Huanyi Xie <74809554+xiehuanyi@users.noreply.github.com>
Date: Tue, 6 Oct 2026 22:08:31 +0300
Subject: [PATCH 2/2] fix: preserve nested fields returned by coerce

---
 lib/yargs-parser.ts   |  1 +
 test/yargs-parser.mjs | 13 +++++++++++++
 2 files changed, 14 insertions(+)

diff --git a/lib/yargs-parser.ts b/lib/yargs-parser.ts
index 7560b813..cbb202e4 100644
--- a/lib/yargs-parser.ts
+++ b/lib/yargs-parser.ts
@@ -433,6 +433,7 @@ export class YargsParser {
       keys.forEach(key => {
         if (key === '--' || !key.includes('-')) return
         const parts = configuration['dot-notation'] ? key.split('.') : [key]
+        if (parts.length > 1 && typeof checkAllAliases(parts[0], flags.coercions) === 'function') return
         let target = argv
         for (const part of parts.slice(0, -1)) {
           const property = sanitizeKey(part)
diff --git a/test/yargs-parser.mjs b/test/yargs-parser.mjs
index 5c659dca..6140028c 100644
--- a/test/yargs-parser.mjs
+++ b/test/yargs-parser.mjs
@@ -14,6 +14,19 @@ const require = createRequire(import.meta.url);
 should()
 
 describe('yargs-parser', function () {
+  it('preserves parsed-looking keys in plain and frozen coerce results', function () {
+    for (const freeze of [value => value, Object.freeze]) {
+      const value = freeze({ 'literal-key': 'own', 'inner-dash': 'replacement' })
+      const result = parser.detailed('--outer.inner-dash value', {
+        coerce: { outer: () => value },
+        configuration: { 'strip-dashed': true }
+      })
+      expect(result.error).to.equal(null)
+      expect(result.argv.outer).to.equal(value)
+      expect(result.argv.outer['inner-dash']).to.equal('replacement')
+    }
+  })
+
   it('strips dashed option keys at nested paths', function () {
     const result = parser('--outer.inner-dash true --outer.deep.third-dash 5', {
       configuration: { 'strip-dashed': true }