From 7b4fd9459dbb0d23d0fed18bece582001eaeec33 Mon Sep 17 00:00:00 2001
From: Randy Stauner <randy.stauner@shopify.com>
Date: Wed, 24 May 2023 11:21:26 -0700
Subject: [PATCH] Convert string arg to Pathname in relative_path_from

It is not documented but CRuby does it:
https://github.com/ruby/ruby/blob/381475f02e6b44ae729f9403637b30c445b622e5/ext/pathname/lib/pathname.rb#L512
---
 CHANGELOG.md                                          | 1 +
 lib/truffle/pathname.rb                               | 1 +
 spec/ruby/library/pathname/relative_path_from_spec.rb | 4 ++++
 3 files changed, 6 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index afcea6128c72..865e733142c2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,7 @@ Compatibility:
 * Fix `Array#[]` with `ArithmeticSequence` argument when step is negative (#3039, @itarato).
 * Fix `Range#size` and return `nil` for beginningless Range when end isn't Numeric (#3039, @rwstauner).
 * Alias `String#-@` to `String#dedup` (#3039, @itarato).
+* Fix `Pathname#relative_path_from` to convert string arguments to Pathname objects (@rwstauner).
 
 Performance:
 
diff --git a/lib/truffle/pathname.rb b/lib/truffle/pathname.rb
index 782f7f2eaadd..64ab34b30942 100644
--- a/lib/truffle/pathname.rb
+++ b/lib/truffle/pathname.rb
@@ -763,6 +763,7 @@ def each_child(with_directory = true, &b)
   # This method has existed since 1.8.1.
   #
   def relative_path_from(base_directory)
+    base_directory = Pathname.new(base_directory) unless Primitive.is_a?(base_directory, Pathname)
     dest_directory = self.cleanpath.to_s
     base_directory = base_directory.cleanpath.to_s
     dest_prefix = dest_directory
diff --git a/spec/ruby/library/pathname/relative_path_from_spec.rb b/spec/ruby/library/pathname/relative_path_from_spec.rb
index abe9c80a4529..133a149849f0 100644
--- a/spec/ruby/library/pathname/relative_path_from_spec.rb
+++ b/spec/ruby/library/pathname/relative_path_from_spec.rb
@@ -48,4 +48,8 @@ def relative_path_str(dest, base)
     relative_path_str('..', '..').should == '.'
     relative_path_str('..', '.').should == '..'
   end
+
+  it 'converts string argument to Pathname' do
+    Pathname.new('/usr/bin/ls').relative_path_from('/usr').to_s.should == 'bin/ls'
+  end
 end