diff --git a/autoload/fern/fri.vim b/autoload/fern/fri.vim
index cb3b8b7f..65885866 100644
--- a/autoload/fern/fri.vim
+++ b/autoload/fern/fri.vim
@@ -22,7 +22,7 @@ function! fern#fri#parse(expr) abort
   endif
   let [authority, remains] = s:split1(remains, escape('/', s:PATTERN))
   if empty(remains)
-    let remaings = authority
+    let remains = authority
     let authority = ''
   endif
   let [path, remains] = s:split1(remains, escape(';', s:PATTERN))
@@ -74,7 +74,7 @@ function! s:parse_query(query) abort
   call map(terms, { _, v -> (split(v, '=', 1) + [v:true])[:1] })
   call map(terms, { _, v ->
         \ extend(obj, {
-        \   s:decode(v[0]): s:decode(v[1])
+        \   s:decode(v[0]): type(v[1]) is# v:t_string ? s:decode(v[1]) : v[1],
         \ })
         \})
   return obj
@@ -123,22 +123,13 @@ function! s:encode_fragment(pchar) abort
 endfunction
 
 function! s:encode(str, pattern) abort
-  let chars = map(
-        \ split(a:str, '\zs'),
-        \ { _, v -> v =~# a:pattern ? printf('%%%X', char2nr(v)) : v },
-        \)
-  return join(chars, '')
+  let Sub = { m -> printf('%%%X', char2nr(m[0])) }
+  return substitute(a:str, a:pattern, Sub, 'g')
 endfunction
 
 function! s:decode(str) abort
-  let str = a:str
-  let [hex, s, e] = matchstrpos(str, '%\zs[0-9a-fA-F]\{2}')
-  while !empty(hex)
-    let repl = nr2char(str2nr(hex, 16))
-    let str = substitute(str, '%' . hex, escape(repl, '&'), 'ig')
-    let [hex, s, e] = matchstrpos(str, '%\zs[0-9a-fA-F]\{2}', s + 1)
-  endwhile
-  return str
+  let Sub = { m -> nr2char(str2nr(m[1], 16)) }
+  return substitute(a:str, '%\([0-9a-fA-F]\{2}\)', Sub, 'g')
 endfunction
 
 function! s:split1(str, pattern) abort
diff --git a/test/fern/fri.vimspec b/test/fern/fri.vimspec
index fd3b50c2..621ad1e3 100644
--- a/test/fern/fri.vimspec
+++ b/test/fern/fri.vimspec
@@ -127,6 +127,30 @@ Describe fern#fri
             \}
       Assert Equals(fern#fri#parse(expr), want)
     End
+
+    It returns FRI for 'file:///foo%20bar%20baz'
+      let expr = 'file:///foo%20bar%20baz'
+      let want = {
+            \ 'scheme': 'file',
+            \ 'authority': '',
+            \ 'path': 'foo bar baz',
+            \ 'query': {},
+            \ 'fragment': '',
+            \}
+      Assert Equals(fern#fri#parse(expr), want)
+    End
+
+    It returns FRI for 'fri://qux/file:///foo%252520bar%252520baz'
+      let expr = 'fri://qux/file:///foo%252520bar%252520baz'
+      let want = {
+            \ 'scheme': 'fri',
+            \ 'authority': 'qux',
+            \ 'path': 'file:///foo%2520bar%2520baz',
+            \ 'query': {},
+            \ 'fragment': '',
+            \}
+      Assert Equals(fern#fri#parse(expr), want)
+    End
   End
 
   Describe #format()
@@ -200,6 +224,30 @@ Describe fern#fri
             \}
       Assert Equals(fern#fri#format(want), expr)
     End
+
+    It formats FRI to 'file:///foo%20bar%20baz'
+      let expr = 'file:///foo%20bar%20baz'
+      let want = {
+            \ 'scheme': 'file',
+            \ 'authority': '',
+            \ 'path': 'foo bar baz',
+            \ 'query': {},
+            \ 'fragment': '',
+            \}
+      Assert Equals(fern#fri#format(want), expr)
+    End
+
+    It formats FRI to 'fri://qux/file:///foo%252520bar%252520baz'
+      let expr = 'fri://qux/file:///foo%252520bar%252520baz'
+      let want = {
+            \ 'scheme': 'fri',
+            \ 'authority': 'qux',
+            \ 'path': 'file:///foo%2520bar%2520baz',
+            \ 'query': {},
+            \ 'fragment': '',
+            \}
+      Assert Equals(fern#fri#format(want), expr)
+    End
   End
 
   Describe #encode()
@@ -228,6 +276,15 @@ Describe fern#fri
       Assert Equals(fern#fri#encode('=', pattern), '%3D')
       Assert Equals(fern#fri#encode(' ', pattern), '%20')
     End
+
+    It encodes all percent character (%)
+      Assert Equals(fern#fri#encode('%%'), '%25%25')
+    End
+
+    It encodes not a string then returns a string
+      Assert Same(fern#fri#encode(v:true), 'v:true')
+      Assert Same(fern#fri#encode(42), '42')
+    End
   End
 
   Describe #decode()
@@ -256,5 +313,20 @@ Describe fern#fri
       Assert Equals(fern#fri#decode('%2523'), '%23')
       Assert Equals(fern#fri#decode('%23'), '#')
     End
+
+    It decodes all percent character (%)
+      Assert Equals(fern#fri#decode('%23%23'), '##')
+    End
+
+    It decodes all percent character (%) only one depth
+      Assert Equals(fern#fri#decode('%252523%252523'), '%2523%2523')
+      Assert Equals(fern#fri#decode('%2523%2523'), '%23%23')
+      Assert Equals(fern#fri#decode('%23%23'), '##')
+    End
+
+    It decodes not a string then returns a string
+      Assert Same(fern#fri#decode(v:true), 'v:true')
+      Assert Same(fern#fri#decode(42), '42')
+    End
   End
 End