Merge #7288

7288: Give a more clear error when user tries to `bundle open` a default gem r=deivid-rodriguez a=deivid-rodriguez

### What was the end-user problem that led to this PR?

The problem was that `bundle open` doesn't currently support opening default gems, but crashes with a very verbose and unclear error when the user tries to do it. 

### What was your diagnosis of the problem?

My diagnosis was that we should give a more clear error in this case.

### What is your fix for the problem, implemented in this PR?

My fix is a rebased and improved version of #4882, that detects the situation and gives a better error. 

### Why did you choose this fix out of the possible options?

I chose this fix because it was already created and it's simpler than adding support for opening default gems, which is more problematic because they can't be pristine'd easily if edited and might not be in a writable location.

Closes #4882.
Fixes #4436.

Co-authored-by: David Rodríguez <deivid.rodriguez@riseup.net>
Co-authored-by: Zehan Zhao <cnallenzhao@gmail.com>

2 files changed, 93 insertions, 74 deletions

diff --git a/lib/bundler/cli/open.rb b/lib/bundler/cli/open.rb
index 552fe6f128..df32e2f38b 100644
--- a/lib/bundler/cli/open.rb
+++ b/lib/bundler/cli/open.rb
@@ -14,12 +14,16 @@ module Bundler
       editor = [ENV["BUNDLER_EDITOR"], ENV["VISUAL"], ENV["EDITOR"]].find {|e| !e.nil? && !e.empty? }
       return Bundler.ui.info("To open a bundled gem, set $EDITOR or $BUNDLER_EDITOR") unless editor
       return unless spec = Bundler::CLI::Common.select_spec(name, :regex_match)
-      path = spec.full_gem_path
-      Dir.chdir(path) do
-        command = Shellwords.split(editor) + [path]
-        Bundler.with_original_env do
-          system(*command)
-        end || Bundler.ui.info("Could not run '#{command.join(" ")}'")
+      if spec.default_gem?
+        Bundler.ui.info "Unable to open #{name} because it's a default gem, so the directory it would normally be installed to does not exist."
+      else
+        path = spec.full_gem_path
+        Dir.chdir(path) do
+          command = Shellwords.split(editor) + [path]
+          Bundler.with_original_env do
+            system(*command)
+          end || Bundler.ui.info("Could not run '#{command.join(" ")}'")
+        end
       end
     end
   end
diff --git a/spec/commands/open_spec.rb b/spec/commands/open_spec.rb
index 6eb6262a2b..649ae06fda 100644
--- a/spec/commands/open_spec.rb
+++ b/spec/commands/open_spec.rb
@@ -1,92 +1,107 @@
 # frozen_string_literal: true
 
 RSpec.describe "bundle open" do
-  before :each do
-    install_gemfile <<-G
-      source "#{file_uri_for(gem_repo1)}"
-      gem "rails"
-    G
-  end
-
-  it "opens the gem with BUNDLER_EDITOR as highest priority" do
-    bundle "open rails", :env => { "EDITOR" => "echo editor", "VISUAL" => "echo visual", "BUNDLER_EDITOR" => "echo bundler_editor" }
-    expect(out).to include("bundler_editor #{default_bundle_path("gems", "rails-2.3.2")}")
-  end
+  context "when opening a regular gem" do
+    before do
+      install_gemfile <<-G
+        source "#{file_uri_for(gem_repo1)}"
+        gem "rails"
+      G
+    end
 
-  it "opens the gem with VISUAL as 2nd highest priority" do
-    bundle "open rails", :env => { "EDITOR" => "echo editor", "VISUAL" => "echo visual", "BUNDLER_EDITOR" => "" }
-    expect(out).to include("visual #{default_bundle_path("gems", "rails-2.3.2")}")
-  end
+    it "opens the gem with BUNDLER_EDITOR as highest priority" do
+      bundle "open rails", :env => { "EDITOR" => "echo editor", "VISUAL" => "echo visual", "BUNDLER_EDITOR" => "echo bundler_editor" }
+      expect(out).to include("bundler_editor #{default_bundle_path("gems", "rails-2.3.2")}")
+    end
 
-  it "opens the gem with EDITOR as 3rd highest priority" do
-    bundle "open rails", :env => { "EDITOR" => "echo editor", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
-    expect(out).to include("editor #{default_bundle_path("gems", "rails-2.3.2")}")
-  end
+    it "opens the gem with VISUAL as 2nd highest priority" do
+      bundle "open rails", :env => { "EDITOR" => "echo editor", "VISUAL" => "echo visual", "BUNDLER_EDITOR" => "" }
+      expect(out).to include("visual #{default_bundle_path("gems", "rails-2.3.2")}")
+    end
 
-  it "complains if no EDITOR is set" do
-    bundle "open rails", :env => { "EDITOR" => "", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
-    expect(out).to eq("To open a bundled gem, set $EDITOR or $BUNDLER_EDITOR")
-  end
+    it "opens the gem with EDITOR as 3rd highest priority" do
+      bundle "open rails", :env => { "EDITOR" => "echo editor", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
+      expect(out).to include("editor #{default_bundle_path("gems", "rails-2.3.2")}")
+    end
 
-  it "complains if gem not in bundle" do
-    bundle "open missing", :env => { "EDITOR" => "echo editor", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
-    expect(err).to match(/could not find gem 'missing'/i)
-  end
+    it "complains if no EDITOR is set" do
+      bundle "open rails", :env => { "EDITOR" => "", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
+      expect(out).to eq("To open a bundled gem, set $EDITOR or $BUNDLER_EDITOR")
+    end
 
-  it "does not blow up if the gem to open does not have a Gemfile" do
-    git = build_git "foo"
-    ref = git.ref_for("master", 11)
+    it "complains if gem not in bundle" do
+      bundle "open missing", :env => { "EDITOR" => "echo editor", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
+      expect(err).to match(/could not find gem 'missing'/i)
+    end
 
-    install_gemfile <<-G
-      source "#{file_uri_for(gem_repo1)}"
-      gem 'foo', :git => "#{lib_path("foo-1.0")}"
-    G
+    it "does not blow up if the gem to open does not have a Gemfile" do
+      git = build_git "foo"
+      ref = git.ref_for("master", 11)
 
-    bundle "open foo", :env => { "EDITOR" => "echo editor", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
-    expect(out).to match("editor #{default_bundle_path.join("bundler/gems/foo-1.0-#{ref}")}")
-  end
+      install_gemfile <<-G
+        source "#{file_uri_for(gem_repo1)}"
+        gem 'foo', :git => "#{lib_path("foo-1.0")}"
+      G
 
-  it "suggests alternatives for similar-sounding gems" do
-    bundle "open Rails", :env => { "EDITOR" => "echo editor", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
-    expect(err).to match(/did you mean rails\?/i)
-  end
+      bundle "open foo", :env => { "EDITOR" => "echo editor", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
+      expect(out).to match("editor #{default_bundle_path.join("bundler/gems/foo-1.0-#{ref}")}")
+    end
 
-  it "opens the gem with short words" do
-    bundle "open rec", :env => { "EDITOR" => "echo editor", "VISUAL" => "echo visual", "BUNDLER_EDITOR" => "echo bundler_editor" }
+    it "suggests alternatives for similar-sounding gems" do
+      bundle "open Rails", :env => { "EDITOR" => "echo editor", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
+      expect(err).to match(/did you mean rails\?/i)
+    end
 
-    expect(out).to include("bundler_editor #{default_bundle_path("gems", "activerecord-2.3.2")}")
-  end
+    it "opens the gem with short words" do
+      bundle "open rec", :env => { "EDITOR" => "echo editor", "VISUAL" => "echo visual", "BUNDLER_EDITOR" => "echo bundler_editor" }
 
-  it "select the gem from many match gems" do
-    env = { "EDITOR" => "echo editor", "VISUAL" => "echo visual", "BUNDLER_EDITOR" => "echo bundler_editor" }
-    bundle "open active", :env => env do |input, _, _|
-      input.puts "2"
+      expect(out).to include("bundler_editor #{default_bundle_path("gems", "activerecord-2.3.2")}")
     end
 
-    expect(out).to match(/bundler_editor #{default_bundle_path('gems', 'activerecord-2.3.2')}\z/)
-  end
+    it "select the gem from many match gems" do
+      env = { "EDITOR" => "echo editor", "VISUAL" => "echo visual", "BUNDLER_EDITOR" => "echo bundler_editor" }
+      bundle "open active", :env => env do |input, _, _|
+        input.puts "2"
+      end
 
-  it "allows selecting exit from many match gems" do
-    env = { "EDITOR" => "echo editor", "VISUAL" => "echo visual", "BUNDLER_EDITOR" => "echo bundler_editor" }
-    bundle! "open active", :env => env do |input, _, _|
-      input.puts "0"
+      expect(out).to match(/bundler_editor #{default_bundle_path('gems', 'activerecord-2.3.2')}\z/)
     end
-  end
 
-  it "performs an automatic bundle install" do
-    gemfile <<-G
-      source "#{file_uri_for(gem_repo1)}"
-      gem "rails"
-      gem "foo"
-    G
+    it "allows selecting exit from many match gems" do
+      env = { "EDITOR" => "echo editor", "VISUAL" => "echo visual", "BUNDLER_EDITOR" => "echo bundler_editor" }
+      bundle! "open active", :env => env do |input, _, _|
+        input.puts "0"
+      end
+    end
+
+    it "performs an automatic bundle install" do
+      gemfile <<-G
+        source "#{file_uri_for(gem_repo1)}"
+        gem "rails"
+        gem "foo"
+      G
+
+      bundle "config set auto_install 1"
+      bundle "open rails", :env => { "EDITOR" => "echo editor", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
+      expect(out).to include("Installing foo 1.0")
+    end
 
-    bundle "config set auto_install 1"
-    bundle "open rails", :env => { "EDITOR" => "echo editor", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
-    expect(out).to include("Installing foo 1.0")
+    it "opens the editor with a clean env" do
+      bundle "open", :env => { "EDITOR" => "sh -c 'env'", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
+      expect(out).not_to include("BUNDLE_GEMFILE=")
+    end
   end
 
-  it "opens the editor with a clean env" do
-    bundle "open", :env => { "EDITOR" => "sh -c 'env'", "VISUAL" => "", "BUNDLER_EDITOR" => "" }
-    expect(out).not_to include("BUNDLE_GEMFILE=")
+  context "when opening a default gem" do
+    before do
+      install_gemfile <<-G
+        gem "json"
+      G
+    end
+
+    it "throws proper error when trying to open default gem" do
+      bundle "open json", :env => { "EDITOR" => "echo editor", "VISUAL" => "echo visual", "BUNDLER_EDITOR" => "echo bundler_editor" }
+      expect(out).to include("Unable to open json because it's a default gem, so the directory it would normally be installed to does not exist.")
+    end
   end
 end