[rubygems/rubygems] Refactor specs to not try to remove folders that don't exist

This has the following benefits:

* Avoid duplicated work in some specs that first build a repo, and then
  overwrite it with a completely different set of gems.
* Reduce RSpec nesting and improve readability.
* The change also made surfaces several specs that were incorrect since
  they were unintentionally not testing the right thing.

ruby/rubygems@ed430883e0

Author: deivid-rodriguez

spec/bundler/cache/gems_spec.rb

@@ -291,7 +291,7 @@
         expect(cached_gem("platform_specific-1.0-java")).to exist
       end
 
-      simulate_new_machine
+      pristine_system_gems :bundler
 
       simulate_platform "x86-darwin-100" do
         install_gemfile <<-G
@@ -312,7 +312,8 @@
         path: cached_myrack.parent,
         rubygems_version: "1.3.2"
 
-      simulate_new_machine
+      FileUtils.rm_rf default_bundle_path
+      system_gems :bundler
 
       FileUtils.rm bundled_app_lock
       bundle :install, raise_on_error: false
@@ -344,7 +345,8 @@
         c.checksum gem_repo1, "myrack", "1.0.0"
       end
 
-      simulate_new_machine
+      FileUtils.rm_rf default_bundle_path
+      system_gems :bundler
 
       lockfile <<-L
         GEM
@@ -369,7 +371,7 @@
       setup_main_repo
       cached_gem("myrack-1.0.0").rmtree
       build_gem "myrack", "1.0.0", path: bundled_app("vendor/cache")
-      simulate_new_machine
+      pristine_system_gems :bundler
 
       lockfile <<-L
         GEM

spec/bundler/cache/git_spec.rb

@@ -164,7 +164,7 @@
     bundle "config set path vendor/bundle"
     bundle :install
 
-    simulate_new_machine
+    pristine_system_gems :bundler
     with_path_as "" do
       bundle "config set deployment true"
       bundle "install --local"
@@ -181,10 +181,8 @@
     G
     bundle "config set cache_all true"
     bundle :cache, "all-platforms" => true
-    FileUtils.rm_rf Dir.glob(default_bundle_path("bundler/gems/extensions/**/foo-1.0-*")).first.to_s
-    FileUtils.rm_rf Dir.glob(default_bundle_path("bundler/gems/foo-1.0-*")).first.to_s
 
-    simulate_new_machine
+    pristine_system_gems :bundler
     bundle "config set frozen true"
     bundle "install --local --verbose"
     expect(out).to_not include("Fetching")
@@ -200,12 +198,9 @@
     G
     bundle "config set cache_all true"
     bundle :cache, "all-platforms" => true
-    FileUtils.rm_rf Dir.glob(default_bundle_path("bundler/gems/extensions/**/foo-1.0-*")).first.to_s
-    FileUtils.rm_rf Dir.glob(default_bundle_path("bundler/gems/foo-1.0-*")).first.to_s
 
-    simulate_new_machine
+    pristine_system_gems :bundler
     bundle "config set frozen true"
-    FileUtils.rm_rf "#{default_bundle_path}/cache/bundler/git/foo-1.0-*"
     bundle "install --local --verbose"
     expect(out).to_not include("Fetching")
     expect(the_bundle).to include_gem "foo 1.0"
@@ -220,12 +215,9 @@
     G
     bundle "config set cache_all true"
     bundle :cache, "all-platforms" => true
-    FileUtils.rm_rf Dir.glob(default_bundle_path("bundler/gems/extensions/**/foo-1.0-*")).first.to_s
-    FileUtils.rm_rf Dir.glob(default_bundle_path("bundler/gems/foo-1.0-*")).first.to_s
 
-    simulate_new_machine
+    pristine_system_gems :bundler
     bundle "config set frozen true"
-    FileUtils.rm_rf "#{default_bundle_path}/cache/bundler/git/foo-1.0-*"
 
     # Remove untracked files (including the empty refs dir in the cache)
     Dir.chdir(bundled_app) do
@@ -388,7 +380,7 @@
     bundle "config set cache_all true"
     bundle :cache, "all-platforms" => true, :install => false
 
-    simulate_new_machine
+    pristine_system_gems :bundler
     with_path_as "" do
       bundle "config set deployment true"
       bundle :install, local: true

spec/bundler/commands/cache_spec.rb

@@ -356,7 +356,7 @@
       G
 
       bundle :cache
-      simulate_new_machine
+      pristine_system_gems :bundler
       FileUtils.rm_rf gem_repo2
 
       bundle "install --local"
@@ -371,7 +371,7 @@
       G
 
       bundle :cache
-      simulate_new_machine
+      pristine_system_gems :bundler
       FileUtils.rm_rf gem_repo2
 
       bundle "config set --local deployment true"
@@ -388,7 +388,7 @@
       G
 
       bundle :cache
-      simulate_new_machine
+      pristine_system_gems :bundler
       FileUtils.rm_rf gem_repo2
 
       bundle "config set --local cache_all_platforms true"
@@ -445,9 +445,8 @@
         bundle "config set path vendor/bundle"
         bundle :cache, artifice: "compact_index", env: { "BUNDLER_SPEC_GEM_REPO" => gem_repo4.to_s }
 
-        build_repo4 do
-          # simulate removal of all remote gems
-        end
+        # simulate removal of all remote gems
+        empty_repo4
 
         # delete compact index cache
         FileUtils.rm_rf home(".bundle/cache/compact_index")
@@ -483,7 +482,7 @@
         bundle :cache
       end
 
-      simulate_new_machine
+      pristine_system_gems :bundler
 
       bundle "config set --local force_ruby_platform true"
 

spec/bundler/commands/check_spec.rb

@@ -328,7 +328,8 @@
     end
 
     it "shows what is missing with the current Gemfile if it is not satisfied" do
-      simulate_new_machine
+      FileUtils.rm_rf default_bundle_path
+      system_gems :bundler
       bundle :check, raise_on_error: false
       expect(err).to match(/The following gems are missing/)
       expect(err).to include("* myrack (1.0")

spec/bundler/commands/install_spec.rb

@@ -1550,88 +1550,94 @@ def run
   end
 
   context "with --prefer-local flag" do
-    before do
-      build_repo4 do
-        build_gem "foo", "1.0.1"
-        build_gem "foo", "1.0.0"
-        build_gem "bar", "1.0.0"
+    context "and gems available locally" do
+      before do
+        build_repo4 do
+          build_gem "foo", "1.0.1"
+          build_gem "foo", "1.0.0"
+          build_gem "bar", "1.0.0"
 
-        build_gem "a", "1.0.0" do |s|
-          s.add_dependency "foo", "~> 1.0.0"
-        end
+          build_gem "a", "1.0.0" do |s|
+            s.add_dependency "foo", "~> 1.0.0"
+          end
 
-        build_gem "b", "1.0.0" do |s|
-          s.add_dependency "foo", "~> 1.0.1"
+          build_gem "b", "1.0.0" do |s|
+            s.add_dependency "foo", "~> 1.0.1"
+          end
         end
+
+        system_gems "foo-1.0.0", path: default_bundle_path, gem_repo: gem_repo4
       end
 
-      system_gems "foo-1.0.0", path: default_bundle_path, gem_repo: gem_repo4
-    end
+      it "fetches remote sources when not available locally" do
+        install_gemfile <<-G, "prefer-local": true, verbose: true
+          source "https://gem.repo4"
 
-    it "fetches remote sources when not available locally" do
-      install_gemfile <<-G, "prefer-local": true, verbose: true
-        source "https://gem.repo4"
-
-        gem "foo"
-        gem "bar"
-      G
+          gem "foo"
+          gem "bar"
+        G
 
-      expect(out).to include("Using foo 1.0.0").and include("Fetching bar 1.0.0").and include("Installing bar 1.0.0")
-      expect(last_command).to be_success
-    end
+        expect(out).to include("Using foo 1.0.0").and include("Fetching bar 1.0.0").and include("Installing bar 1.0.0")
+        expect(last_command).to be_success
+      end
 
-    it "fetches remote sources when local version does not match requirements" do
-      install_gemfile <<-G, "prefer-local": true, verbose: true
-        source "https://gem.repo4"
+      it "fetches remote sources when local version does not match requirements" do
+        install_gemfile <<-G, "prefer-local": true, verbose: true
+          source "https://gem.repo4"
 
-        gem "foo", "1.0.1"
-        gem "bar"
-      G
+          gem "foo", "1.0.1"
+          gem "bar"
+        G
 
-      expect(out).to include("Fetching foo 1.0.1").and include("Installing foo 1.0.1").and include("Fetching bar 1.0.0").and include("Installing bar 1.0.0")
-      expect(last_command).to be_success
-    end
+        expect(out).to include("Fetching foo 1.0.1").and include("Installing foo 1.0.1").and include("Fetching bar 1.0.0").and include("Installing bar 1.0.0")
+        expect(last_command).to be_success
+      end
 
-    it "uses the locally available version for sub-dependencies when possible" do
-      install_gemfile <<-G, "prefer-local": true, verbose: true
-        source "https://gem.repo4"
+      it "uses the locally available version for sub-dependencies when possible" do
+        install_gemfile <<-G, "prefer-local": true, verbose: true
+          source "https://gem.repo4"
 
-        gem "a"
-      G
+          gem "a"
+        G
 
-      expect(out).to include("Using foo 1.0.0").and include("Fetching a 1.0.0").and include("Installing a 1.0.0")
-      expect(last_command).to be_success
-    end
+        expect(out).to include("Using foo 1.0.0").and include("Fetching a 1.0.0").and include("Installing a 1.0.0")
+        expect(last_command).to be_success
+      end
 
-    it "fetches remote sources for sub-dependencies when the locally available version does not satisfy the requirement" do
-      install_gemfile <<-G, "prefer-local": true, verbose: true
-        source "https://gem.repo4"
+      it "fetches remote sources for sub-dependencies when the locally available version does not satisfy the requirement" do
+        install_gemfile <<-G, "prefer-local": true, verbose: true
+          source "https://gem.repo4"
 
-        gem "b"
-      G
+          gem "b"
+        G
 
-      expect(out).to include("Fetching foo 1.0.1").and include("Installing foo 1.0.1").and include("Fetching b 1.0.0").and include("Installing b 1.0.0")
-      expect(last_command).to be_success
+        expect(out).to include("Fetching foo 1.0.1").and include("Installing foo 1.0.1").and include("Fetching b 1.0.0").and include("Installing b 1.0.0")
+        expect(last_command).to be_success
+      end
     end
 
-    it "resolves to the latest version if no gems are available locally" do
-      build_repo4 do
-        build_gem "myreline", "0.3.8"
-        build_gem "debug", "0.2.1"
+    context "and no gems available locally" do
+      before do
+        build_repo4 do
+          build_gem "myreline", "0.3.8"
+          build_gem "debug", "0.2.1"
 
-        build_gem "debug", "1.10.0" do |s|
-          s.add_dependency "myreline"
+          build_gem "debug", "1.10.0" do |s|
+            s.add_dependency "myreline"
+          end
         end
       end
 
-      install_gemfile <<~G, "prefer-local": true, verbose: true
-        source "https://gem.repo4"
+      it "resolves to the latest version if no gems are available locally" do
+        install_gemfile <<~G, "prefer-local": true, verbose: true
+          source "https://gem.repo4"
 
-        gem "debug"
-      G
+          gem "debug"
+        G
 
-      expect(out).to include("Fetching debug 1.10.0").and include("Installing debug 1.10.0").and include("Fetching myreline 0.3.8").and include("Installing myreline 0.3.8")
-      expect(last_command).to be_success
+        expect(out).to include("Fetching debug 1.10.0").and include("Installing debug 1.10.0").and include("Fetching myreline 0.3.8").and include("Installing myreline 0.3.8")
+        expect(last_command).to be_success
+      end
     end
   end