Make version conflict messages better

lib/bundler/definition.rb

@@ -855,8 +855,8 @@ def metadata_dependencies
           concat_ruby_version_requirements(locked_ruby_version_object) unless @unlock[:ruby]
         end
         [
-          Dependency.new("ruby\0", ruby_versions),
-          Dependency.new("rubygems\0", Gem::VERSION),
+          Dependency.new("Ruby\0", ruby_versions),
+          Dependency.new("RubyGems\0", Gem::VERSION),
         ]
       end
     end

lib/bundler/resolver.rb

@@ -302,21 +302,32 @@ def formatted_versions_with_platforms(versions_with_platforms)
     end
 
     def version_conflict_message(e)
+      # only show essential conflicts, if possible
+      conflicts = e.conflicts.dup
+      conflicts.delete_if do |_name, conflict|
+        deps = conflict.requirement_trees.map(&:last).flatten(1)
+        !Bundler::VersionRanges.empty?(*Bundler::VersionRanges.for_many(deps.map(&:requirement)))
+      end
+      e = Molinillo::VersionConflict.new(conflicts, e.specification_provider) unless conflicts.empty?
+
+      solver_name = "Bundler"
+      possibility_type = "gem"
       e.message_with_trees(
-        :solver_name => "Bundler",
-        :possibility_type => "gem",
+        :solver_name => solver_name,
+        :possibility_type => possibility_type,
         :reduce_trees => lambda do |trees|
+          # called first, because we want to reduce the amount of work required to find maximal empty sets
+          trees.uniq! {|t| t.flatten.map {|dep| [dep.name, dep.requirement] } }
+
           # bail out if tree size is too big for Array#combination to make any sense
           return trees if trees.size > 15
           maximal = 1.upto(trees.size).map do |size|
             trees.map(&:last).flatten(1).combination(size).to_a
           end.flatten(1).select do |deps|
             Bundler::VersionRanges.empty?(*Bundler::VersionRanges.for_many(deps.map(&:requirement)))
           end.min_by(&:size)
-          trees.reject! {|t| !maximal.include?(t.last) } if maximal
 
-          trees = trees.sort_by {|t| t.flatten.map(&:to_s) }
-          trees.uniq! {|t| t.flatten.map {|dep| [dep.name, dep.requirement] } }
+          trees.reject! {|t| !maximal.include?(t.last) } if maximal
 
           trees.sort_by {|t| t.reverse.map(&:name) }
         end,
@@ -351,7 +362,11 @@ def version_conflict_message(e)
               []
             end.compact.map(&:to_s).uniq.sort
 
-            o << "Could not find gem '#{SharedHelpers.pretty_dependency(conflict.requirement)}'"
+            metadata_requirement = name.end_with?("\0")
+
+            o << "Could not find gem '" unless metadata_requirement
+            o << SharedHelpers.pretty_dependency(conflict.requirement)
+            o << "'" unless metadata_requirement
             if conflict.requirement_trees.first.size > 1
               o << ", which is required by "
               o << "gem '#{SharedHelpers.pretty_dependency(conflict.requirement_trees.first[-2])}',"
@@ -360,12 +375,21 @@ def version_conflict_message(e)
 
             o << if relevant_sources.empty?
                    "in any of the sources.\n"
+                 elsif metadata_requirement
+                   "is not available in #{relevant_sources.join(" or ")}"
                  else
                    "in any of the relevant sources:\n  #{relevant_sources * "\n  "}\n"
                  end
           end
         end,
-        :version_for_spec => lambda {|spec| spec.version }
+        :version_for_spec => lambda {|spec| spec.version },
+        :incompatible_version_message_for_conflict => lambda do |name, _conflict|
+          if name.end_with?("\0")
+            %(#{solver_name} found conflicting requirements for the #{name} version:)
+          else
+            %(#{solver_name} could not find compatible versions for #{possibility_type} "#{name}":)
+          end
+        end
       )
     end
 

lib/bundler/resolver/spec_group.rb

@@ -94,10 +94,10 @@ def metadata_dependencies(spec, platform)
         return [] if !spec.is_a?(EndpointSpecification) && !spec.is_a?(Gem::Specification)
         dependencies = []
         if !spec.required_ruby_version.nil? && !spec.required_ruby_version.none?
-          dependencies << DepProxy.new(Gem::Dependency.new("ruby\0", spec.required_ruby_version), platform)
+          dependencies << DepProxy.new(Gem::Dependency.new("Ruby\0", spec.required_ruby_version), platform)
         end
         if !spec.required_rubygems_version.nil? && !spec.required_rubygems_version.none?
-          dependencies << DepProxy.new(Gem::Dependency.new("rubygems\0", spec.required_rubygems_version), platform)
+          dependencies << DepProxy.new(Gem::Dependency.new("RubyGems\0", spec.required_rubygems_version), platform)
         end
         dependencies
       end

lib/bundler/source/metadata.rb

@@ -5,8 +5,10 @@ class Source
     class Metadata < Source
       def specs
         @specs ||= Index.build do |idx|
-          idx << Gem::Specification.new("ruby\0", RubyVersion.system.to_gem_version_with_patchlevel)
-          idx << Gem::Specification.new("rubygems\0", Gem::VERSION)
+          idx << Gem::Specification.new("Ruby\0", RubyVersion.system.to_gem_version_with_patchlevel)
+          idx << Gem::Specification.new("RubyGems\0", Gem::VERSION) do |s|
+            s.required_rubygems_version = Gem::Requirement.default
+          end
 
           idx << Gem::Specification.new do |s|
             s.name     = "bundler"

lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/vertex.rb

@@ -130,11 +130,21 @@ def hash
       # dependency graph?
       # @return true iff there is a path following edges within this {#graph}
       def path_to?(other)
-        equal?(other) || successors.any? { |v| v.path_to?(other) }
+        _path_to?(other)
       end
 
       alias descendent? path_to?
 
+      # @param [Vertex] other the vertex to check if there's a path to
+      # @param [Set<Vertex>] visited the vertices of {#graph} that have been visited
+      # @return [Boolean] whether there is a path to `other` from `self`
+      def _path_to?(other, visited = Set.new)
+        return false unless visited.add?(self)
+        return true if equal?(other)
+        successors.any? { |v| v._path_to?(other, visited) }
+      end
+      protected :_path_to?
+
       # Is there a path from `other` to `self` following edges in the
       # dependency graph?
       # @return true iff there is a path following edges within this {#graph}

lib/bundler/vendor/molinillo/lib/molinillo/errors.rb

@@ -18,7 +18,7 @@ class NoSuchDependencyError < ResolverError
     # @param [Array<Object>] required_by @see {#required_by}
     def initialize(dependency, required_by = [])
       @dependency = dependency
-      @required_by = required_by
+      @required_by = required_by.uniq
       super()
     end
 
@@ -101,9 +101,14 @@ def message_with_trees(opts = {})
       printable_requirement = opts.delete(:printable_requirement) { proc { |req| req.to_s } }
       additional_message_for_conflict = opts.delete(:additional_message_for_conflict) { proc {} }
       version_for_spec = opts.delete(:version_for_spec) { proc(&:to_s) }
+      incompatible_version_message_for_conflict = opts.delete(:incompatible_version_message_for_conflict) do
+        proc do |name, _conflict|
+          %(#{solver_name} could not find compatible versions for #{possibility_type} "#{name}":)
+        end
+      end
 
       conflicts.sort.reduce(''.dup) do |o, (name, conflict)|
-        o << %(\n#{solver_name} could not find compatible versions for #{possibility_type} "#{name}":\n)
+        o << "\n" << incompatible_version_message_for_conflict.call(name, conflict) << "\n"
         if conflict.locked_requirement
           o << %(  In snapshot (#{name_for_locking_dependency_source}):\n)
           o << %(    #{printable_requirement.call(conflict.locked_requirement)}\n)

lib/bundler/vendor/molinillo/lib/molinillo/gem_metadata.rb

@@ -2,5 +2,5 @@
 
 module Bundler::Molinillo
   # The version of Bundler::Molinillo.
-  VERSION = '0.6.5'.freeze
+  VERSION = '0.6.6'.freeze
 end

lib/bundler/version_ranges.rb

@@ -5,11 +5,42 @@ module VersionRanges
     NEq = Struct.new(:version)
     ReqR = Struct.new(:left, :right)
     class ReqR
-      Endpoint = Struct.new(:version, :inclusive)
+      Endpoint = Struct.new(:version, :inclusive) do
+        def <=>(other)
+          if version.equal?(INFINITY)
+            return 0 if other.version.equal?(INFINITY)
+            return 1
+          elsif other.version.equal?(INFINITY)
+            return -1
+          end
+
+          comp = version <=> other.version
+          return comp unless comp.zero?
+
+          if inclusive && !other.inclusive
+            1
+          elsif !inclusive && other.inclusive
+            -1
+          else
+            0
+          end
+        end
+      end
+
       def to_s
         "#{left.inclusive ? "[" : "("}#{left.version}, #{right.version}#{right.inclusive ? "]" : ")"}"
       end
-      INFINITY = Object.new.freeze
+      INFINITY = begin
+        inf = Object.new
+        def inf.to_s
+          "∞"
+        end
+        def inf.<=>(other)
+          return 0 if other.equal?(self)
+          1
+        end
+        inf.freeze
+      end
       ZERO = Gem::Version.new("0.a")
 
       def cover?(v)
@@ -32,6 +63,15 @@ def single?
         left.version == right.version
       end
 
+      def <=>(other)
+        return -1 if other.equal?(INFINITY)
+
+        comp = left <=> other.left
+        return comp unless comp.zero?
+
+        right <=> other.right
+      end
+
       UNIVERSAL = ReqR.new(ReqR::Endpoint.new(Gem::Version.new("0.a"), true), ReqR::Endpoint.new(ReqR::INFINITY, false)).freeze
     end
 
@@ -57,7 +97,7 @@ def self.for(requirement)
       end.uniq
       ranges, neqs = ranges.partition {|r| !r.is_a?(NEq) }
 
-      [ranges.sort_by {|range| [range.left.version, range.left.inclusive ? 0 : 1] }, neqs.map(&:version)]
+      [ranges.sort, neqs.map(&:version)]
     end
 
     def self.empty?(ranges, neqs)
@@ -66,8 +106,14 @@ def self.empty?(ranges, neqs)
         next false if curr_range.single? && neqs.include?(curr_range.left.version)
         next curr_range if last_range.right.version == ReqR::INFINITY
         case last_range.right.version <=> curr_range.left.version
-        when 1 then next curr_range
-        when 0 then next(last_range.right.inclusive && curr_range.left.inclusive && !neqs.include?(curr_range.left.version) && curr_range)
+        # higher
+        when 1 then next ReqR.new(curr_range.left, last_range.right)
+        # equal
+        when 0
+          if last_range.right.inclusive && curr_range.left.inclusive && !neqs.include?(curr_range.left.version)
+            ReqR.new(curr_range.left, [curr_range.right, last_range.right].max)
+          end
+        # lower
         when -1 then next false
         end
       end

spec/bundler/version_ranges_spec.rb

@@ -25,9 +25,12 @@
     include_examples "empty?", false, ">= 1.0.0", "< 2.0.0"
     include_examples "empty?", false, "~> 1"
     include_examples "empty?", false, "~> 2.0", "~> 2.1"
+    include_examples "empty?", true, ">= 4.1.0", "< 5.0", "= 5.2.1"
+    include_examples "empty?", true, "< 5.0", "< 5.3", "< 6.0", "< 6", "= 5.2.0", "> 2", ">= 3.0", ">= 3.1", ">= 3.2", ">= 4.0.0", ">= 4.1.0", ">= 4.2.0", ">= 4.2", ">= 4"
     include_examples "empty?", true, "!= 1", "< 2", "> 2"
     include_examples "empty?", true, "!= 1", "<= 1", ">= 1"
     include_examples "empty?", true, "< 2", "> 2"
+    include_examples "empty?", true, "< 2", "> 2", "= 2"
     include_examples "empty?", true, "= 1", "!= 1"
     include_examples "empty?", true, "= 1", "= 2"
     include_examples "empty?", true, "= 1", "~> 2"

spec/install/gems/resolving_spec.rb

@@ -142,15 +142,14 @@
           expect(out).to_not include("Gem::InstallError: require_ruby requires Ruby version > 9000")
 
           nice_error = strip_whitespace(<<-E).strip
-            Bundler could not find compatible versions for gem "ruby\0":
+            Bundler found conflicting requirements for the Ruby\0 version:
               In Gemfile:
-                ruby\0 (#{error_message_requirement})
+                Ruby\0 (#{error_message_requirement})
 
                 require_ruby was resolved to 1.0, which depends on
-                  ruby\0 (> 9000)
+                  Ruby\0 (> 9000)
 
-            Could not find gem 'ruby\0 (> 9000)', which is required by gem 'require_ruby', in any of the relevant sources:
-              the local ruby installation
+            Ruby\0 (> 9000), which is required by gem 'require_ruby', is not available in the local ruby installation
           E
           expect(last_command.bundler_err).to end_with(nice_error)
         end

spec/resolver/basic_spec.rb

@@ -157,10 +157,10 @@
         s.required_ruby_version = "~> 2.0.0"
       end
 
-      gem "ruby\0", "1.8.7"
+      gem "Ruby\0", "1.8.7"
     end
     dep "foo"
-    dep "ruby\0", "1.8.7"
+    dep "Ruby\0", "1.8.7"
 
     deps = []
     @deps.each do |d|

spec/support/indexes.rb

@@ -76,7 +76,7 @@ def an_awesome_index
         gem "rack-mount", %w[0.4 0.5 0.5.1 0.5.2 0.6]
 
         # --- Pre-release support
-        gem "rubygems\0", ["1.3.2"]
+        gem "RubyGems\0", ["1.3.2"]
 
         # --- Rails
         versions "1.2.3 2.2.3 2.3.5 3.0.0.beta 3.0.0.beta1" do |version|
@@ -413,7 +413,7 @@ def optional_prereleases_index
         gem("b", %w[0.9.0 1.5.0 2.0.0.pre])
 
         # --- Pre-release support
-        gem "rubygems\0", ["1.3.2"]
+        gem "RubyGems\0", ["1.3.2"]
       end
     end
   end