From 20e4262fb994177cb41aeb278544882a05d52782 Mon Sep 17 00:00:00 2001
From: Mike McQuaid <mike@mikemcquaid.com>
Date: Wed, 3 Apr 2019 10:32:29 +0100
Subject: [PATCH] unpack_strategy: prioritise extension instead.

Instead of only looking at the extension when invoked as part of
Homebrew's formulae' download strategies instead prioritise the
extension if it actually exists. When it does not, fall back to the
magic detection logic which is likely to be more reliable.

Fixes https://github.com/Homebrew/brew/issues/5895
---
 Library/Homebrew/download_strategy.rb            |  8 ++++----
 Library/Homebrew/unpack_strategy.rb              | 10 +++++-----
 Library/Homebrew/unpack_strategy/uncompressed.rb |  2 +-
 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/Library/Homebrew/download_strategy.rb b/Library/Homebrew/download_strategy.rb
index a6af403b3a..37f8e87907 100644
--- a/Library/Homebrew/download_strategy.rb
+++ b/Library/Homebrew/download_strategy.rb
@@ -54,11 +54,11 @@ class AbstractDownloadStrategy
   # Unlike {Resource#stage}, this does not take a block.
   def stage
     UnpackStrategy.detect(cached_location,
-                          extension_only: true,
+                          prioritise_extension: true,
                           ref_type: @ref_type, ref: @ref)
-                  .extract_nestedly(basename:       basename,
-                                    extension_only: true,
-                                    verbose:        ARGV.verbose? && !shutup)
+                  .extract_nestedly(basename:             basename,
+                                    prioritise_extension: true,
+                                    verbose:              ARGV.verbose? && !shutup)
     chdir
   end
 
diff --git a/Library/Homebrew/unpack_strategy.rb b/Library/Homebrew/unpack_strategy.rb
index b18dde19a5..0617eed0a6 100644
--- a/Library/Homebrew/unpack_strategy.rb
+++ b/Library/Homebrew/unpack_strategy.rb
@@ -88,10 +88,10 @@ module UnpackStrategy
     strategies.find { |s| s.can_extract?(path) }
   end
 
-  def self.detect(path, extension_only: false, type: nil, ref_type: nil, ref: nil)
+  def self.detect(path, prioritise_extension: false, type: nil, ref_type: nil, ref: nil)
     strategy = from_type(type) if type
 
-    if extension_only
+    if prioritise_extension && path.extname.present?
       strategy ||= from_extension(path.extname)
       strategy ||= strategies.select { |s| s < Directory || s == Fossil }
                              .find { |s| s.can_extract?(path) }
@@ -120,7 +120,7 @@ module UnpackStrategy
     extract_to_dir(unpack_dir, basename: basename, verbose: verbose)
   end
 
-  def extract_nestedly(to: nil, basename: nil, verbose: false, extension_only: false)
+  def extract_nestedly(to: nil, basename: nil, verbose: false, prioritise_extension: false)
     Dir.mktmpdir do |tmp_unpack_dir|
       tmp_unpack_dir = Pathname(tmp_unpack_dir)
 
@@ -131,9 +131,9 @@ module UnpackStrategy
       if children.count == 1 && !children.first.directory?
         FileUtils.chmod "+rw", children.first, verbose: verbose
 
-        s = UnpackStrategy.detect(children.first, extension_only: extension_only)
+        s = UnpackStrategy.detect(children.first, prioritise_extension: prioritise_extension)
 
-        s.extract_nestedly(to: to, verbose: verbose, extension_only: extension_only)
+        s.extract_nestedly(to: to, verbose: verbose, prioritise_extension: prioritise_extension)
         next
       end
 
diff --git a/Library/Homebrew/unpack_strategy/uncompressed.rb b/Library/Homebrew/unpack_strategy/uncompressed.rb
index fe627bf818..4ce44acc3b 100644
--- a/Library/Homebrew/unpack_strategy/uncompressed.rb
+++ b/Library/Homebrew/unpack_strategy/uncompressed.rb
@@ -2,7 +2,7 @@ module UnpackStrategy
   class Uncompressed
     include UnpackStrategy
 
-    def extract_nestedly(extension_only: false, **options)
+    def extract_nestedly(prioritise_extension: false, **options)
       extract(**options)
     end