Auto merge of #5496 - bundler:seg-exec-outside-bundle, r=segiddins

Friendly error when exec'ing to gem outside the bundle

Closes #5487

lib/bundler/rubygems_integration.rb

@@ -320,7 +320,7 @@ def reverse_rubygems_kernel_mixin
       end
     end
 
-    def replace_gem(specs)
+    def replace_gem(specs, specs_by_name)
       reverse_rubygems_kernel_mixin
 
       executables = specs.map(&:executables).flatten
@@ -337,31 +337,26 @@ def replace_gem(specs)
             dep = Gem::Dependency.new(dep, reqs)
           end
 
-          spec = specs.find {|s| s.name == dep.name }
-
-          if spec.nil?
-
-            e = Gem::LoadError.new "#{dep.name} is not part of the bundle. Add it to Gemfile."
-            e.name = dep.name
-            if e.respond_to?(:requirement=)
-              e.requirement = dep.requirement
-            else
-              e.version_requirement = dep.requirement
-            end
-            raise e
-          elsif dep !~ spec
-            e = Gem::LoadError.new "can't activate #{dep}, already activated #{spec.full_name}. " \
-                                   "Make sure all dependencies are added to Gemfile."
-            e.name = dep.name
-            if e.respond_to?(:requirement=)
-              e.requirement = dep.requirement
-            else
-              e.version_requirement = dep.requirement
-            end
-            raise e
+          if spec = specs_by_name[dep.name]
+            return true if dep.matches_spec?(spec)
           end
 
-          true
+          message = if spec.nil?
+            "#{dep.name} is not part of the bundle." \
+            " Add it to your #{Bundler.default_gemfile.basename}."
+          else
+            "can't activate #{dep}, already activated #{spec.full_name}. " \
+            "Make sure all dependencies are added to Gemfile."
+          end
+
+          e = Gem::LoadError.new(message)
+          e.name = dep.name
+          if e.respond_to?(:requirement=)
+            e.requirement = dep.requirement
+          elsif e.respond_to?(:version_requirement=)
+            e.version_requirement = dep.requirement
+          end
+          raise e
         end
 
         # TODO: delete this in 2.0, it's a backwards compatibility shim
@@ -393,20 +388,34 @@ def stub_source_index(specs)
     # Used to make bin stubs that are not created by bundler work
     # under bundler. The new Gem.bin_path only considers gems in
     # +specs+
-    def replace_bin_path(specs)
+    def replace_bin_path(specs, specs_by_name)
       gem_class = (class << Gem; self; end)
 
       redefine_method(gem_class, :find_spec_for_exe) do |gem_name, *args|
         exec_name = args.first
 
+        spec_with_name = specs_by_name[gem_name]
         spec = if exec_name
-          specs.find {|s| s.name == gem_name && s.executables.include?(exec_name) } ||
+          if spec_with_name && spec_with_name.executables.include?(exec_name)
+            spec_with_name
+          else
             specs.find {|s| s.executables.include?(exec_name) }
+          end
         else
-          specs.find {|s| s.name == gem_name }
+          spec_with_name
         end
-        raise(Gem::Exception, "can't find executable #{exec_name}") unless spec
+
+        unless spec
+          message = "can't find executable #{exec_name} for gem #{gem_name}"
+          if !exec_name || spec_with_name.nil?
+            message += ". #{gem_name} is not currently included in the bundle, " \
+                       "perhaps you meant to add it to your #{Bundler.default_gemfile.basename}?"
+          end
+          raise Gem::Exception, message
+        end
+
         raise Gem::Exception, "no default executable for #{spec.full_name}" unless exec_name ||= spec.default_executable
+
         unless spec.name == name
           Bundler::SharedHelpers.major_deprecation \
             "Bundler is using a binstub that was created for a different gem.\n" \
@@ -450,11 +459,14 @@ def replace_refresh
     # Replace or hook into Rubygems to provide a bundlerized view
     # of the world.
     def replace_entrypoints(specs)
-      replace_gem(specs)
+      specs_by_name = specs.reduce({}) do |h, s|
+        h[s.name] = s
+        h
+      end
 
+      replace_gem(specs, specs_by_name)
       stub_rubygems(specs)
-
-      replace_bin_path(specs)
+      replace_bin_path(specs, specs_by_name)
       replace_refresh
 
       Gem.clear_paths

spec/commands/exec_spec.rb

@@ -218,6 +218,32 @@
     expect(out).to include("bundler: exec needs a command to run")
   end
 
+  it "raises a helpful error when exec'ing to something outside of the bundle", :rubygems => ">= 2.6.2" do
+    install_gemfile! <<-G
+      source "file://#{gem_repo1}"
+      gem "with_license"
+    G
+    [true, false].each do |l|
+      bundle! "config disable_exec_load #{l}"
+      bundle "exec rackup"
+      expect(err).to include "can't find executable rackup for gem rack. rack is not currently included in the bundle, perhaps you meant to add it to your Gemfile?"
+    end
+  end
+
+  # Different error message on old RG versions (before activate_bin_path) because they
+  # called `Kernel#gem` directly
+  it "raises a helpful error when exec'ing to something outside of the bundle", :rubygems => "< 2.6.2" do
+    install_gemfile! <<-G
+      source "file://#{gem_repo1}"
+      gem "with_license"
+    G
+    [true, false].each do |l|
+      bundle! "config disable_exec_load #{l}"
+      bundle "exec rackup"
+      expect(err).to include "rack is not part of the bundle. Add it to your Gemfile."
+    end
+  end
+
   describe "with help flags" do
     each_prefix = proc do |string, &blk|
       1.upto(string.length) {|l| blk.call(string[0, l]) }

spec/runtime/setup_spec.rb

@@ -891,7 +891,7 @@
         end
       R
 
-      expect(out).to eq("rack is not part of the bundle. Add it to Gemfile.")
+      expect(out).to eq("rack is not part of the bundle. Add it to your Gemfile.")
     end
 
     it "sets GEM_HOME appropriately" do