Add bundle install conservative updating to update

In the discussion on new 1.13 Conservative Bundle Updates (see
https://github.com/bundler/bundler-features/issues/122), some users
would like to have the same Conservative Updating (see
http://bundler.io/v1.12/man/bundle-install.1.html#CONSERVATIVE-UPDATING)
behavior available in `bundle install` when a declared dependency is
altered in the Gemfile, also available in the `bundle update` command.

This adds a new option called `--conservative` to both `bundle update`
and `bundle lock`. The option only applies on `bundle lock` if the
`--update` option is in use.

The internal flag is more descriptive as to what actually takes place:
It locks any shared dependencies from the gem(s) being updated.

This also promotes the previously added patch level options to being
shown in command-line help, anticipating a 1.14 release, to make these
public and documented.

4 files changed, 24 insertions, 16 deletions

diff --git a/lib/bundler/cli.rb b/lib/bundler/cli.rb
index f92ecb1c33..6ee9adf431 100644
--- a/lib/bundler/cli.rb
+++ b/lib/bundler/cli.rb
@@ -215,14 +215,16 @@ module Bundler
       "Update ruby specified in Gemfile.lock"
     method_option "bundler", :type => :string, :lazy_default => "> 0.a", :banner =>
       "Update the locked version of bundler"
-    method_option "patch", :type => :boolean, :hide => true, :banner =>
+    method_option "patch", :type => :boolean, :banner =>
       "Prefer updating only to next patch version"
-    method_option "minor", :type => :boolean, :hide => true, :banner =>
+    method_option "minor", :type => :boolean, :banner =>
       "Prefer updating only to next minor version"
-    method_option "major", :type => :boolean, :hide => true, :banner =>
+    method_option "major", :type => :boolean, :banner =>
       "Prefer updating to next major version (default)"
-    method_option "strict", :type => :boolean, :hide => true, :banner =>
+    method_option "strict", :type => :boolean, :banner =>
       "Do not allow any gem to be updated past latest --patch/--minor/--major"
+    method_option "conservative", :type => :boolean, :banner =>
+      "Use bundle install conservative update behavior and do not allowed shared dependencies to be updated."
     def update(*gems)
       require "bundler/cli/update"
       Update.new(options, gems).run
@@ -459,14 +461,16 @@ module Bundler
       "add a new platform to the lockfile"
     method_option "remove-platform", :type => :array, :default => [], :banner =>
       "remove a platform from the lockfile"
-    method_option "patch", :type => :boolean, :hide => true, :banner =>
-      "Prefer updating only to next patch version"
-    method_option "minor", :type => :boolean, :hide => true, :banner =>
-      "Prefer updating only to next minor version"
-    method_option "major", :type => :boolean, :hide => true, :banner =>
-      "Prefer updating to next major version (default)"
-    method_option "strict", :type => :boolean, :hide => true, :banner =>
-      "Do not allow any gem to be updated past latest --patch/--minor/--major"
+    method_option "patch", :type => :boolean, :banner =>
+      "If updating, prefer updating only to next patch version"
+    method_option "minor", :type => :boolean, :banner =>
+      "If updating, prefer updating only to next minor version"
+    method_option "major", :type => :boolean, :banner =>
+      "If updating, prefer updating to next major version (default)"
+    method_option "strict", :type => :boolean, :banner =>
+      "If updating, do not allow any gem to be updated past latest --patch | --minor | --major"
+    method_option "conservative", :type => :boolean, :banner =>
+      "If updating, use bundle install conservative update behavior and do not allowed shared dependencies to be updated."
     def lock
       require "bundler/cli/lock"
       Lock.new(options).run
diff --git a/lib/bundler/cli/lock.rb b/lib/bundler/cli/lock.rb
index eb47c9efb0..225a07aa97 100644
--- a/lib/bundler/cli/lock.rb
+++ b/lib/bundler/cli/lock.rb
@@ -22,7 +22,7 @@ module Bundler
       Bundler::Fetcher.disable_endpoint = options["full-index"]
 
       update = options[:update]
-      update = { :gems => update } if update.is_a?(Array)
+      update = { :gems => update, :lock_shared_dependencies => options[:conservative] } if update.is_a?(Array)
       definition = Bundler.definition(update)
 
       Bundler::CLI::Common.config_gem_version_promoter(Bundler.definition, options) if options[:update]
diff --git a/lib/bundler/cli/update.rb b/lib/bundler/cli/update.rb
index 51de98bf34..585fe38e17 100644
--- a/lib/bundler/cli/update.rb
+++ b/lib/bundler/cli/update.rb
@@ -37,7 +37,8 @@ module Bundler
           gems.concat(specs.map(&:name))
         end
 
-        Bundler.definition(:gems => gems, :sources => sources, :ruby => options[:ruby])
+        Bundler.definition(:gems => gems, :sources => sources, :ruby => options[:ruby],
+                           :lock_shared_dependencies => options[:conservative])
       end
 
       Bundler::CLI::Common.config_gem_version_promoter(Bundler.definition, options)
diff --git a/lib/bundler/definition.rb b/lib/bundler/definition.rb
index 8a6bf0d17c..8141e6e54e 100644
--- a/lib/bundler/definition.rb
+++ b/lib/bundler/definition.rb
@@ -105,8 +105,11 @@ module Bundler
       add_current_platform unless Bundler.settings[:frozen]
 
       @path_changes = converge_paths
-      eager_unlock = expand_dependencies(@unlock[:gems])
-      @unlock[:gems] = @locked_specs.for(eager_unlock).map(&:name)
+
+      unless @unlock[:lock_shared_dependencies]
+        eager_unlock = expand_dependencies(@unlock[:gems])
+        @unlock[:gems] = @locked_specs.for(eager_unlock).map(&:name)
+      end
 
       @gem_version_promoter = create_gem_version_promoter