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path: root/spec/unit/parser/compiler_spec.rb
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#!/usr/bin/env ruby

require File.dirname(__FILE__) + '/../../spec_helper'

class CompilerTestResource
    attr_accessor :builtin, :virtual, :evaluated, :type, :title

    def initialize(type, title)
        @type = type
        @title = title
    end

    def [](attr)
        return nil if attr == :stage
        :main
    end

    def ref
        "#{type.to_s.capitalize}[#{title}]"
    end

    def evaluated?
        @evaluated
    end

    def builtin?
        @builtin
    end

    def virtual?
        @virtual
    end

    def evaluate
    end
end

describe Puppet::Parser::Compiler do
    def resource(type, title)
        Puppet::Parser::Resource.new(type, title, :scope => @scope)
    end

    before :each do
        @node = Puppet::Node.new "testnode"
        @known_resource_types = Puppet::Resource::TypeCollection.new "development"
        @compiler = Puppet::Parser::Compiler.new(@node)
        @scope = Puppet::Parser::Scope.new(:compiler => @compiler, :source => stub('source'))
        @scope_resource = Puppet::Parser::Resource.new(:file, "/my/file", :scope => @scope)
        @scope.resource = @scope_resource
        @compiler.environment.stubs(:known_resource_types).returns @known_resource_types
    end

    it "should have a class method that compiles, converts, and returns a catalog" do
        compiler = stub 'compiler'
        Puppet::Parser::Compiler.expects(:new).with(@node).returns compiler
        catalog = stub 'catalog'
        compiler.expects(:compile).returns catalog
        converted_catalog = stub 'converted_catalog'
        catalog.expects(:to_resource).returns converted_catalog

        Puppet::Parser::Compiler.compile(@node).should equal(converted_catalog)
    end

    it "should fail intelligently when a class-level compile fails" do
        Puppet::Parser::Compiler.expects(:new).raises ArgumentError
        lambda { Puppet::Parser::Compiler.compile(@node) }.should raise_error(Puppet::Error)
    end

    it "should use the node's environment as its environment" do
        @compiler.environment.should equal(@node.environment)
    end

    it "should include the resource type collection helper" do
        Puppet::Parser::Compiler.ancestors.should be_include(Puppet::Resource::TypeCollectionHelper)
    end

    it "should be able to return a class list containing all added classes" do
        @compiler.add_class ""
        @compiler.add_class "one"
        @compiler.add_class "two"

        @compiler.classlist.sort.should == %w{one two}.sort
    end

    describe "when initializing" do

        it "should set its node attribute" do
            @compiler.node.should equal(@node)
        end
        it "should detect when ast nodes are absent" do
            @compiler.ast_nodes?.should be_false
        end

        it "should detect when ast nodes are present" do
            @known_resource_types.expects(:nodes?).returns true
            @compiler.ast_nodes?.should be_true
        end

        it "should copy the known_resource_types version to the catalog" do
            @compiler.catalog.version.should == @known_resource_types.version
        end

        it "should copy any node classes into the class list" do
            node = Puppet::Node.new("mynode")
            node.classes = %w{foo bar}
            compiler = Puppet::Parser::Compiler.new(node)

            compiler.classlist.should include("foo")
            compiler.classlist.should include("bar")
        end

        it "should add a 'main' stage to the catalog" do
            @compiler.catalog.resource(:stage, :main).should be_instance_of(Puppet::Parser::Resource)
        end
    end

    describe "when managing scopes" do

        it "should create a top scope" do
            @compiler.topscope.should be_instance_of(Puppet::Parser::Scope)
        end

        it "should be able to create new scopes" do
            @compiler.newscope(@compiler.topscope).should be_instance_of(Puppet::Parser::Scope)
        end

        it "should correctly set the level of newly created scopes" do
            @compiler.newscope(@compiler.topscope, :level => 5).level.should == 5
        end

        it "should set the parent scope of the new scope to be the passed-in parent" do
            scope = mock 'scope'
            newscope = @compiler.newscope(scope)

            newscope.parent.should equal(scope)
        end

        it "should set the parent scope of the new scope to its topscope if the parent passed in is nil" do
            scope = mock 'scope'
            newscope = @compiler.newscope(nil)

            newscope.parent.should equal(@compiler.topscope)
        end
    end

    describe "when compiling" do

        def compile_methods
            [:set_node_parameters, :evaluate_main, :evaluate_ast_node, :evaluate_node_classes, :evaluate_generators, :fail_on_unevaluated,
                :finish, :store, :extract, :evaluate_relationships]
        end

        # Stub all of the main compile methods except the ones we're specifically interested in.
        def compile_stub(*except)
            (compile_methods - except).each { |m| @compiler.stubs(m) }
        end

        it "should set node parameters as variables in the top scope" do
            params = {"a" => "b", "c" => "d"}
            @node.stubs(:parameters).returns(params)
            compile_stub(:set_node_parameters)
            @compiler.compile
            @compiler.topscope.lookupvar("a").should == "b"
            @compiler.topscope.lookupvar("c").should == "d"
        end

        it "should set the client and server versions on the catalog" do
            params = {"clientversion" => "2", "serverversion" => "3"}
            @node.stubs(:parameters).returns(params)
            compile_stub(:set_node_parameters)
            @compiler.compile
            @compiler.catalog.client_version.should == "2"
            @compiler.catalog.server_version.should == "3"
        end

        it "should evaluate any existing classes named in the node" do
            classes = %w{one two three four}
            main = stub 'main'
            one = stub 'one', :name => "one"
            three = stub 'three', :name => "three"
            @node.stubs(:name).returns("whatever")
            @node.stubs(:classes).returns(classes)

            @compiler.expects(:evaluate_classes).with(classes, @compiler.topscope)
            @compiler.class.publicize_methods(:evaluate_node_classes) { @compiler.evaluate_node_classes }
        end

        it "should evaluate the main class if it exists" do
            compile_stub(:evaluate_main)
            main_class = @known_resource_types.add Puppet::Resource::Type.new(:hostclass, "")
            main_class.expects(:evaluate_code).with { |r| r.is_a?(Puppet::Parser::Resource) }
            @compiler.topscope.expects(:source=).with(main_class)

            @compiler.compile
        end

        it "should create a new, empty 'main' if no main class exists" do
            compile_stub(:evaluate_main)
            @compiler.compile
            @known_resource_types.find_hostclass([""], "").should be_instance_of(Puppet::Resource::Type)
        end

        it "should add an edge between the main stage and main class" do
            @compiler.compile
            (stage = @compiler.catalog.resource(:stage, "main")).should be_instance_of(Puppet::Parser::Resource)
            (klass = @compiler.catalog.resource(:class, "")).should be_instance_of(Puppet::Parser::Resource)

            @compiler.catalog.edge?(stage, klass).should be_true
        end

        it "should evaluate any node classes" do
            @node.stubs(:classes).returns(%w{one two three four})
            @compiler.expects(:evaluate_classes).with(%w{one two three four}, @compiler.topscope)
            @compiler.send(:evaluate_node_classes)
        end

        it "should evaluate all added collections" do
            colls = []
            # And when the collections fail to evaluate.
            colls << mock("coll1-false")
            colls << mock("coll2-false")
            colls.each { |c| c.expects(:evaluate).returns(false) }

            @compiler.add_collection(colls[0])
            @compiler.add_collection(colls[1])

            compile_stub(:evaluate_generators)
            @compiler.compile
        end

        it "should ignore builtin resources" do
            resource = resource(:file, "testing")

            @compiler.add_resource(@scope, resource)
            resource.expects(:evaluate).never

            @compiler.compile
        end

        it "should evaluate unevaluated resources" do
            resource = CompilerTestResource.new(:file, "testing")

            @compiler.add_resource(@scope, resource)

            # We have to now mark the resource as evaluated
            resource.expects(:evaluate).with { |*whatever| resource.evaluated = true }

            @compiler.compile
        end

        it "should not evaluate already-evaluated resources" do
            resource = resource(:file, "testing")
            resource.stubs(:evaluated?).returns true

            @compiler.add_resource(@scope, resource)
            resource.expects(:evaluate).never

            @compiler.compile
        end

        it "should evaluate unevaluated resources created by evaluating other resources" do
            resource = CompilerTestResource.new(:file, "testing")
            @compiler.add_resource(@scope, resource)

            resource2 = CompilerTestResource.new(:file, "other")

            # We have to now mark the resource as evaluated
            resource.expects(:evaluate).with { |*whatever| resource.evaluated = true; @compiler.add_resource(@scope, resource2) }
            resource2.expects(:evaluate).with { |*whatever| resource2.evaluated = true }


            @compiler.compile
        end

        describe "when finishing" do
            before do
                @compiler.send(:evaluate_main)
                @catalog = @compiler.catalog
            end

            def add_resource(name, parent = nil)
                resource = Puppet::Parser::Resource.new "file", name, :scope => @scope
                @compiler.add_resource(@scope, resource)
                @catalog.add_edge(parent, resource) if parent
                resource
            end

            it "should call finish() on all resources" do
                # Add a resource that does respond to :finish
                resource = Puppet::Parser::Resource.new "file", "finish", :scope => @scope
                resource.expects(:finish)

                @compiler.add_resource(@scope, resource)

                # And one that does not
                dnf_resource = stub_everything "dnf", :ref => "File[dnf]", :type => "file"

                @compiler.add_resource(@scope, dnf_resource)

                @compiler.send(:finish)
            end

            it "should call finish() in add_resource order" do
                resources = sequence('resources')

                resource1 = add_resource("finish1")
                resource1.expects(:finish).in_sequence(resources)

                resource2 = add_resource("finish2")
                resource2.expects(:finish).in_sequence(resources)

                @compiler.send(:finish)
            end

            it "should add each container's metaparams to its contained resources" do
                main = @catalog.resource(:class, :main)
                main[:noop] = true

                resource1 = add_resource("meh", main)

                @compiler.send(:finish)
                resource1[:noop].should be_true
            end

            it "should add metaparams recursively" do
                main = @catalog.resource(:class, :main)
                main[:noop] = true

                resource1 = add_resource("meh", main)
                resource2 = add_resource("foo", resource1)

                @compiler.send(:finish)
                resource2[:noop].should be_true
            end

            it "should prefer metaparams from immediate parents" do
                main = @catalog.resource(:class, :main)
                main[:noop] = true

                resource1 = add_resource("meh", main)
                resource2 = add_resource("foo", resource1)

                resource1[:noop] = false

                @compiler.send(:finish)
                resource2[:noop].should be_false
            end

            it "should merge tags downward" do
                main = @catalog.resource(:class, :main)
                main.tag("one")

                resource1 = add_resource("meh", main)
                resource1.tag "two"
                resource2 = add_resource("foo", resource1)

                @compiler.send(:finish)
                resource2.tags.should be_include("one")
                resource2.tags.should be_include("two")
            end

            it "should work if only middle resources have metaparams set" do
                main = @catalog.resource(:class, :main)

                resource1 = add_resource("meh", main)
                resource1[:noop] = true
                resource2 = add_resource("foo", resource1)

                @compiler.send(:finish)
                resource2[:noop].should be_true
            end
        end

        it "should return added resources in add order" do
            resource1 = resource(:file, "yay")
            @compiler.add_resource(@scope, resource1)
            resource2 = resource(:file, "youpi")
            @compiler.add_resource(@scope, resource2)

            @compiler.resources.should == [resource1, resource2]
        end

        it "should add resources that do not conflict with existing resources" do
            resource = resource(:file, "yay")
            @compiler.add_resource(@scope, resource)

            @compiler.catalog.should be_vertex(resource)
        end

        it "should fail to add resources that conflict with existing resources" do
            path = Puppet.features.posix? ? "/foo" : "C:/foo"
            file1 = Puppet::Type.type(:file).new :path => path
            file2 = Puppet::Type.type(:file).new :path => path

            @compiler.add_resource(@scope, file1)
            lambda { @compiler.add_resource(@scope, file2) }.should raise_error(Puppet::Resource::Catalog::DuplicateResourceError)
        end

        it "should add an edge from the scope resource to the added resource" do
            resource = resource(:file, "yay")
            @compiler.add_resource(@scope, resource)

            @compiler.catalog.should be_edge(@scope.resource, resource)
        end

        it "should add an edge to any specified stage for class resources" do
            other_stage = resource(:stage, "other")
            @compiler.add_resource(@scope, other_stage)
            resource = resource(:class, "foo")
            resource[:stage] = 'other'

            @compiler.add_resource(@scope, resource)

            @compiler.catalog.edge?(other_stage, resource).should be_true
        end

        it "should fail if a non-class resource attempts to set a stage" do
            other_stage = resource(:stage, "other")
            @compiler.add_resource(@scope, other_stage)
            resource = resource(:file, "foo")
            resource[:stage] = 'other'

            lambda { @compiler.add_resource(@scope, resource) }.should raise_error(ArgumentError)
        end

        it "should fail if an unknown stage is specified" do
            resource = resource(:class, "foo")
            resource[:stage] = 'other'

            lambda { @compiler.add_resource(@scope, resource) }.should raise_error(ArgumentError)
        end

        it "should add edges from the class resources to the main stage if no stage is specified" do
            main = @compiler.catalog.resource(:stage, :main)
            resource = resource(:class, "foo")
            @compiler.add_resource(@scope, resource)

            @compiler.catalog.should be_edge(main, resource)
        end

        it "should not add non-class resources that don't specify a stage to the 'main' stage" do
            main = @compiler.catalog.resource(:stage, :main)
            resource = resource(:file, "foo")
            @compiler.add_resource(@scope, resource)

            @compiler.catalog.should_not be_edge(main, resource)
        end

        it "should not add any parent-edges to stages" do
            stage = resource(:stage, "other")
            @compiler.add_resource(@scope, stage)

            @scope.resource = resource(:class, "foo")

            @compiler.catalog.edge?(@scope.resource, stage).should be_false
        end

        it "should not attempt to add stages to other stages" do
            other_stage = resource(:stage, "other")
            second_stage = resource(:stage, "second")
            @compiler.add_resource(@scope, other_stage)
            @compiler.add_resource(@scope, second_stage)

            second_stage[:stage] = "other"

            @compiler.catalog.edge?(other_stage, second_stage).should be_false
        end

        it "should have a method for looking up resources" do
            resource = resource(:yay, "foo")
            @compiler.add_resource(@scope, resource)
            @compiler.findresource("Yay[foo]").should equal(resource)
        end

        it "should be able to look resources up by type and title" do
            resource = resource(:yay, "foo")
            @compiler.add_resource(@scope, resource)
            @compiler.findresource("Yay", "foo").should equal(resource)
        end

        it "should not evaluate virtual defined resources" do
            resource = resource(:file, "testing")
            resource.virtual = true
            @compiler.add_resource(@scope, resource)

            resource.expects(:evaluate).never

            @compiler.compile
        end
    end

    describe "when evaluating collections" do

        it "should evaluate each collection" do
            2.times { |i|
                coll = mock 'coll%s' % i
                @compiler.add_collection(coll)

                # This is the hard part -- we have to emulate the fact that
                # collections delete themselves if they are done evaluating.
                coll.expects(:evaluate).with do
                    @compiler.delete_collection(coll)
                end
            }

            @compiler.class.publicize_methods(:evaluate_collections) { @compiler.evaluate_collections }
        end

        it "should not fail when there are unevaluated resource collections that do not refer to specific resources" do
            coll = stub 'coll', :evaluate => false
            coll.expects(:resources).returns(nil)

            @compiler.add_collection(coll)

            lambda { @compiler.compile }.should_not raise_error
        end

        it "should fail when there are unevaluated resource collections that refer to a specific resource" do
            coll = stub 'coll', :evaluate => false
            coll.expects(:resources).returns(:something)

            @compiler.add_collection(coll)

            lambda { @compiler.compile }.should raise_error(Puppet::ParseError)
        end

        it "should fail when there are unevaluated resource collections that refer to multiple specific resources" do
            coll = stub 'coll', :evaluate => false
            coll.expects(:resources).returns([:one, :two])

            @compiler.add_collection(coll)

            lambda { @compiler.compile }.should raise_error(Puppet::ParseError)
        end
    end

    describe "when evaluating relationships" do
        it "should evaluate each relationship with its catalog" do
            dep = stub 'dep'
            dep.expects(:evaluate).with(@compiler.catalog)
            @compiler.add_relationship dep
            @compiler.evaluate_relationships
        end
    end

    describe "when told to evaluate missing classes" do

        it "should fail if there's no source listed for the scope" do
            scope = stub 'scope', :source => nil
            proc { @compiler.evaluate_classes(%w{one two}, scope) }.should raise_error(Puppet::DevError)
        end

        it "should tag the catalog with the name of each not-found class" do
            @compiler.catalog.expects(:tag).with("notfound")
            @scope.expects(:find_hostclass).with("notfound").returns(nil)
            @compiler.evaluate_classes(%w{notfound}, @scope)
        end
    end

    describe "when evaluating found classes" do

        before do
            @class = stub 'class', :name => "my::class"
            @scope.stubs(:find_hostclass).with("myclass").returns(@class)

            @resource = stub 'resource', :ref => "Class[myclass]", :type => "file"
        end

        it "should evaluate each class" do
            @compiler.catalog.stubs(:tag)

            @class.expects(:mk_plain_resource).with(@scope)
            @scope.stubs(:class_scope).with(@class)

            @compiler.evaluate_classes(%w{myclass}, @scope)
        end

        it "should not evaluate the resources created for found classes unless asked" do
            @compiler.catalog.stubs(:tag)

            @resource.expects(:evaluate).never

            @class.expects(:mk_plain_resource).returns(@resource)
            @scope.stubs(:class_scope).with(@class)

            @compiler.evaluate_classes(%w{myclass}, @scope)
        end

        it "should immediately evaluate the resources created for found classes when asked" do
            @compiler.catalog.stubs(:tag)

            @resource.expects(:evaluate)
            @class.expects(:mk_plain_resource).returns(@resource)
            @scope.stubs(:class_scope).with(@class)

            @compiler.evaluate_classes(%w{myclass}, @scope, false)
        end

        it "should skip classes that have already been evaluated" do
            @compiler.catalog.stubs(:tag)

            @scope.stubs(:class_scope).with(@class).returns("something")

            @compiler.expects(:add_resource).never

            @resource.expects(:evaluate).never

            Puppet::Parser::Resource.expects(:new).never
            @compiler.evaluate_classes(%w{myclass}, @scope, false)
        end

        it "should skip classes previously evaluated with different capitalization" do
            @compiler.catalog.stubs(:tag)
            @scope.stubs(:find_hostclass).with("MyClass").returns(@class)
            @scope.stubs(:class_scope).with(@class).returns("something")
            @compiler.expects(:add_resource).never
            @resource.expects(:evaluate).never
            Puppet::Parser::Resource.expects(:new).never
            @compiler.evaluate_classes(%w{MyClass}, @scope, false)
        end

        it "should return the list of found classes" do
            @compiler.catalog.stubs(:tag)

            @compiler.stubs(:add_resource)
            @scope.stubs(:find_hostclass).with("notfound").returns(nil)
            @scope.stubs(:class_scope).with(@class)

            Puppet::Parser::Resource.stubs(:new).returns(@resource)
            @class.stubs :mk_plain_resource
            @compiler.evaluate_classes(%w{myclass notfound}, @scope).should == %w{myclass}
        end
    end

    describe "when evaluating AST nodes with no AST nodes present" do

        it "should do nothing" do
            @compiler.expects(:ast_nodes?).returns(false)
            @compiler.known_resource_types.expects(:nodes).never
            Puppet::Parser::Resource.expects(:new).never

            @compiler.send(:evaluate_ast_node)
        end
    end

    describe "when evaluating AST nodes with AST nodes present" do

        before do
            @compiler.known_resource_types.stubs(:nodes?).returns true

            # Set some names for our test
            @node.stubs(:names).returns(%w{a b c})
            @compiler.known_resource_types.stubs(:node).with("a").returns(nil)
            @compiler.known_resource_types.stubs(:node).with("b").returns(nil)
            @compiler.known_resource_types.stubs(:node).with("c").returns(nil)

            # It should check this last, of course.
            @compiler.known_resource_types.stubs(:node).with("default").returns(nil)
        end

        it "should fail if the named node cannot be found" do
            proc { @compiler.send(:evaluate_ast_node) }.should raise_error(Puppet::ParseError)
        end

        it "should evaluate the first node class matching the node name" do
            node_class = stub 'node', :name => "c", :evaluate_code => nil
            @compiler.known_resource_types.stubs(:node).with("c").returns(node_class)

            node_resource = stub 'node resource', :ref => "Node[c]", :evaluate => nil, :type => "node"
            node_class.expects(:mk_plain_resource).returns(node_resource)

            @compiler.compile
        end

        it "should match the default node if no matching node can be found" do
            node_class = stub 'node', :name => "default", :evaluate_code => nil
            @compiler.known_resource_types.stubs(:node).with("default").returns(node_class)

            node_resource = stub 'node resource', :ref => "Node[default]", :evaluate => nil, :type => "node"
            node_class.expects(:mk_plain_resource).returns(node_resource)

            @compiler.compile
        end

        it "should evaluate the node resource immediately rather than using lazy evaluation" do
            node_class = stub 'node', :name => "c"
            @compiler.known_resource_types.stubs(:node).with("c").returns(node_class)

            node_resource = stub 'node resource', :ref => "Node[c]", :type => "node"
            node_class.expects(:mk_plain_resource).returns(node_resource)

            node_resource.expects(:evaluate)

            @compiler.send(:evaluate_ast_node)
        end

        it "should set the node's scope as the top scope" do
            node_resource = stub 'node resource', :ref => "Node[c]", :evaluate => nil, :type => "node"
            node_class = stub 'node', :name => "c", :mk_plain_resource => node_resource

            @compiler.known_resource_types.stubs(:node).with("c").returns(node_class)

            # The #evaluate method normally does this.
            scope = stub 'scope', :source => "mysource"
            @compiler.topscope.expects(:class_scope).with(node_class).returns(scope)
            node_resource.stubs(:evaluate)
            @compiler.stubs :create_settings_scope

            @compiler.compile

            @compiler.topscope.should equal(scope)
        end
    end

    describe "when managing resource overrides" do

        before do
            @override = stub 'override', :ref => "File[/foo]", :type => "my"
            @resource = resource(:file, "/foo")
        end

        it "should be able to store overrides" do
            lambda { @compiler.add_override(@override) }.should_not raise_error
        end

        it "should apply overrides to the appropriate resources" do
            @compiler.add_resource(@scope, @resource)
            @resource.expects(:merge).with(@override)

            @compiler.add_override(@override)

            @compiler.compile
        end

        it "should accept overrides before the related resource has been created" do
            @resource.expects(:merge).with(@override)

            # First store the override
            @compiler.add_override(@override)

            # Then the resource
            @compiler.add_resource(@scope, @resource)

            # And compile, so they get resolved
            @compiler.compile
        end

        it "should fail if the compile is finished and resource overrides have not been applied" do
            @compiler.add_override(@override)

            lambda { @compiler.compile }.should raise_error(Puppet::ParseError)
        end
    end
end