fix: preserve KnownHostsCommand arguments

src/ssh-config.ts

@@ -7,7 +7,8 @@ import os from 'node:os'
 const RE_SPACE = /\s/
 const RE_LINE_BREAK = /\r|\n/
 const RE_SECTION_DIRECTIVE = /^(Host|Match)$/i
-const RE_MULTI_VALUE_DIRECTIVE = /^(GlobalKnownHostsFile|Host|IPQoS|SendEnv|UserKnownHostsFile|ProxyCommand|Match|CanonicalDomains)$/i
+const RE_MULTI_VALUE_DIRECTIVE = /^(GlobalKnownHostsFile|Host|IPQoS|SendEnv|UserKnownHostsFile|ProxyCommand|KnownHostsCommand|Match|CanonicalDomains)$/i
+const RE_COMMAND_DIRECTIVE = /^(ProxyCommand|KnownHostsCommand)$/i
 const RE_QUOTE_DIRECTIVE = /^(?:CertificateFile|IdentityFile|IdentityAgent|User)$/i
 const RE_SINGLE_LINE_DIRECTIVE = /^(Include|IdentityFile)$/i
 
@@ -303,7 +304,7 @@ export default class SSHConfig extends Array<Line> {
       const key = computeOpts?.ignoreCase ? name.toLowerCase() : name
       let val: string | string[]
       if (Array.isArray(value)) {
-        if (/ProxyCommand/i.test(key)) {
+        if (RE_COMMAND_DIRECTIVE.test(key)) {
           val = value.map(({ val, separator, quoted }) => {
             return `${separator}${quoted ? `"${val.replace(/"/g, '\\"')}"` : val}`
           }).join('').trim()

test/legacy/compute.test.ts

@@ -300,4 +300,14 @@ describe('compute', function() {
     assert.equal(result.ProxyCommand, '"/foo/bar - baz/proxylauncher.sh" "/some/param with space"')
   })
 
+  it('.compute should preserve KnownHostsCommand arguments', async () => {
+    const config = SSHConfig.parse(`
+      Host *.sbx
+        KnownHostsCommand "/opt/homebrew/bin/sbx" ssh known-hosts %H
+    `)
+
+    const result = config.compute({ Host: 'example.sbx' })
+    assert.equal(result.KnownHostsCommand, '"/opt/homebrew/bin/sbx" ssh known-hosts %H')
+  })
+
 })

test/legacy/stringify.test.ts

@@ -167,6 +167,18 @@ describe('stringify', function() {
     `)
   })
 
+  it('.stringify KnownHostsCommand with a quoted executable', function() {
+    const config = parse(`
+      Host *.sbx
+        KnownHostsCommand "/opt/homebrew/bin/sbx" ssh known-hosts %H
+    `)
+
+    assert.equal(stringify(config), `
+      Host *.sbx
+        KnownHostsCommand "/opt/homebrew/bin/sbx" ssh known-hosts %H
+    `)
+  })
+
   it('.stringify Match with criteria', function() {
     const config = parse(`
       Match host foo final exec "return 0"

test/unit/compute.test.ts

@@ -318,6 +318,16 @@ describe('compute', function() {
     assert.equal(result.ProxyCommand, '"/foo/bar - baz/proxylauncher.sh" "/some/param with space"')
   })
 
+  it('.compute should preserve KnownHostsCommand arguments', async () => {
+    const config = SSHConfig.parse(`
+      Host *.sbx
+        KnownHostsCommand "/opt/homebrew/bin/sbx" ssh known-hosts %H
+    `)
+
+    const result = config.compute({ Host: 'example.sbx' })
+    assert.equal(result.KnownHostsCommand, '"/opt/homebrew/bin/sbx" ssh known-hosts %H')
+  })
+
   describe('compute with ignoreCase', function() {
     it('.compute with ignoreCase: true should normalize directive names to lowercase', async function() {
       const config = SSHConfig.parse(`

test/unit/stringify.test.ts

@@ -167,6 +167,18 @@ describe('stringify', function() {
     `)
   })
 
+  it('.stringify KnownHostsCommand with a quoted executable', function() {
+    const config = parse(`
+      Host *.sbx
+        KnownHostsCommand "/opt/homebrew/bin/sbx" ssh known-hosts %H
+    `)
+
+    assert.equal(stringify(config), `
+      Host *.sbx
+        KnownHostsCommand "/opt/homebrew/bin/sbx" ssh known-hosts %H
+    `)
+  })
+
   it('.stringify Match with criteria', function() {
     const config = parse(`
       Match host foo final exec "return 0"