From 11f038aae9c993baee9344deb8717fa442a5ae55 Mon Sep 17 00:00:00 2001
From: Nikolai B <nikolai-b@users.noreply.github.com>
Date: Tue, 26 May 2020 20:31:08 +0100
Subject: [PATCH 1/2] Fix spec

assets:clean only removes assets older than 3600 seconds by default
---
 test/test_task.rb | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/test/test_task.rb b/test/test_task.rb
index 81ee6f7b..bd1ba3e8 100644
--- a/test/test_task.rb
+++ b/test/test_task.rb
@@ -114,6 +114,8 @@ def test_clean_with_keep_specified
     FileUtils.cp(path, new_path)
 
     assert File.exist?(new_path)
+    mtime = Time.now - 3601
+    File.utime(mtime, mtime, new_path.to_s)
     digest_path = @assets['foo-modified.js'].digest_path
 
     @rake['assets:precompile'].invoke
@@ -135,7 +137,7 @@ def test_clean_with_keep_specified
 
     @rake['assets:clean'].invoke(0)
     assert File.exist?("#{@dir}/#{digest_path}")
-    # refute File.exist?("#{@dir}/#{old_digest_path}")
+    refute File.exist?("#{@dir}/#{old_digest_path}")
   ensure
     FileUtils.rm(new_path) if new_path
   end

From 762cbde2260d63dc5f8c4895b5e0498218e306b0 Mon Sep 17 00:00:00 2001
From: Nikolai B <nikolai-b@users.noreply.github.com>
Date: Tue, 26 May 2020 20:54:23 +0100
Subject: [PATCH 2/2] Allow age to be specified in assets:clean

Before assets:clean would leave assets with an
mtime less than 3600 seconds ago
---
 README.md                   |  2 +-
 lib/sprockets/rails/task.rb | 14 ++++++++++---
 test/test_task.rb           | 41 +++++++++++++++++++++++++++++++++++++
 3 files changed, 53 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index 45d2d35f..047c1025 100644
--- a/README.md
+++ b/README.md
@@ -23,7 +23,7 @@ Deployment task that compiles any assets listed in `config.assets.precompile` to
 
 **`rake assets:clean`**
 
-Only removes old assets (keeps the most recent 3 copies) from `public/assets`. Useful when doing rolling deploys that may still be serving old assets while the new ones are being compiled.
+Only removes old assets (by default keeps the most recent 3 copies and files created within 3600 ) from `public/assets`. Useful when doing rolling deploys that may still be serving old assets while the new ones are being compiled.  Use `rake assets:clean[3,3600]` to keep the last 3 assets or created within the last hour or `rake assets:clean[1,0]` to keep only the most recent old assets.  This never cleans up the currently used assets.
 
 **`rake assets:clobber`**
 
diff --git a/lib/sprockets/rails/task.rb b/lib/sprockets/rails/task.rb
index 107db04b..8c22bc4a 100644
--- a/lib/sprockets/rails/task.rb
+++ b/lib/sprockets/rails/task.rb
@@ -68,10 +68,18 @@ def define
             end
           end
 
-          desc "Remove old compiled assets"
-          task :clean, [:keep] => :environment do |t, args|
+          desc "Remove old compiled assets.  Arguments\nkeep: minimum previous copies to keep\nage: all assets with age less than this will be kept"
+          task :clean, [:keep, :age] => :environment do |_t, args|
             with_logger do
-              manifest.clean(Integer(args.keep || self.keep))
+              age =
+                if args.age
+                  args.age
+                elsif respond_to?(:age)
+                  age
+                else
+                  3600
+                end
+              manifest.clean(Integer(args.keep || keep), Integer(age))
             end
           end
 
diff --git a/test/test_task.rb b/test/test_task.rb
index bd1ba3e8..d0982801 100644
--- a/test/test_task.rb
+++ b/test/test_task.rb
@@ -141,4 +141,45 @@ def test_clean_with_keep_specified
   ensure
     FileUtils.rm(new_path) if new_path
   end
+
+  def test_clean_with_age_and_keep_specified
+    assert !@environment_ran
+    path     = Pathname.new(@assets['foo.js'].filename)
+    new_path = path.join("../foo-modified.js")
+
+    FileUtils.cp(path, new_path)
+
+    assert File.exist?(new_path)
+    age = 3000
+    mtime = Time.now - age
+    File.utime(mtime, mtime, new_path.to_s)
+    digest_path = @assets['foo-modified.js'].digest_path
+    @rake['assets:precompile'].invoke
+    assert File.exist?("#{@dir}/#{digest_path}")
+    assert @environment_ran
+
+    # clean environment
+    setup
+
+    # modify file
+    File.open(new_path, "a") {|f| f.write("var Bar;") }
+    @rake['assets:precompile'].invoke
+    old_digest_path = digest_path
+    digest_path     = @assets['foo-modified.js'].digest_path
+
+    refute_equal old_digest_path, digest_path
+    assert File.exist?("#{@dir}/#{old_digest_path}")
+    assert File.exist?("#{@dir}/#{digest_path}")
+
+    @rake['assets:clean'].invoke(0, age + 500)
+    assert File.exist?("#{@dir}/#{digest_path}")
+    assert File.exist?("#{@dir}/#{old_digest_path}")
+
+    @rake['assets:clean'].reenable
+    @rake['assets:clean'].invoke(0, age - 500)
+    assert File.exist?("#{@dir}/#{digest_path}")
+    refute File.exist?("#{@dir}/#{old_digest_path}")
+  ensure
+    FileUtils.rm(new_path) if new_path
+  end
 end