Install tools from .deb package

15 files changed, 429 insertions, 111 deletions

diff --git a/spec/fixtures/python/pipenv/specific-python-version/.tool-versions b/spec/fixtures/python/pipenv/specific-python-version/.tool-versions
deleted file mode 100644
index 5f51665..0000000
--- a/spec/fixtures/python/pipenv/specific-python-version/.tool-versions
+++ /dev/null
@@ -1 +0,0 @@
-python 3.4.10
diff --git a/spec/integration/dotnet/nuget_spec.rb b/spec/integration/dotnet/nuget_spec.rb
index c72296e..f640c32 100644
--- a/spec/integration/dotnet/nuget_spec.rb
+++ b/spec/integration/dotnet/nuget_spec.rb
@@ -8,6 +8,7 @@ RSpec.describe "nuget" do
   let(:env) { {} }
 
   before do
+    system("rm -fr /opt/asdf/installs/mono")
     system("rm -fr /opt/gitlab/.nuget/packages")
   end
 
diff --git a/spec/integration/java/gradle_spec.rb b/spec/integration/java/gradle_spec.rb
index 25d7e26..e6bda3c 100644
--- a/spec/integration/java/gradle_spec.rb
+++ b/spec/integration/java/gradle_spec.rb
@@ -122,10 +122,10 @@ plugins {
       runner.add_file('.tool-versions', "gradle 1.9")
     end
 
-    it 'returns an empty report because the plugin we use does not work in this version of the gradle API' do
+    specify do
       expect(subject).to match_schema
-      expect(subject[:dependencies]).to be_empty
-      expect(subject[:licenses]).to be_empty
+      expect(subject.dependency_names).to match_array(['postgresql'])
+      expect(subject.licenses_for('postgresql')).to match_array(['BSD-2-Clause'])
     end
   end
 
diff --git a/spec/integration/java/maven_spec.rb b/spec/integration/java/maven_spec.rb
index 65d8bf5..217035d 100644
--- a/spec/integration/java/maven_spec.rb
+++ b/spec/integration/java/maven_spec.rb
@@ -114,48 +114,6 @@ RSpec.describe "maven" do
     specify { expect(report.licenses_for('jackson-core')).to match_array(['Apache-2.0']) }
   end
 
-  context "when specifying the version of java using environment variables" do
-    let(:output_file) { Pathname.new(runner.project_path.join('output.txt')) }
-
-    before do
-      runner.add_file('custom.sh') do
-        <<~SCRIPT
-        #!/bin/bash -l
-
-        java -version &> '#{output_file}'
-        SCRIPT
-      end
-    end
-
-    it 'prioritizes `LM_JAVA_VERSION` over the `ASDF_JAVA_VERSION`' do
-      runner.scan(env: {
-        'ASDF_JAVA_VERSION' => 'adopt-openjdk-11.0.7+10',
-        'LM_JAVA_VERSION' => '8',
-        'SETUP_CMD' => 'bash custom.sh'
-      })
-
-      expect(output_file).to exist
-      expect(output_file.read).to include('openjdk version "1.8.0_252"')
-    end
-
-    it 'reads the ASDF_JAVA_VERSION' do
-      runner.scan(env: {
-        'ASDF_JAVA_VERSION' => 'adopt-openjdk-11.0.7+10.1',
-        'SETUP_CMD' => 'bash custom.sh'
-      })
-
-      expect(output_file).to exist
-      expect(output_file.read).to include('openjdk version "11.0.7"')
-    end
-
-    it 'defaults to java 8' do
-      runner.scan(env: { 'SETUP_CMD' => 'bash custom.sh' })
-
-      expect(output_file).to exist
-      expect(output_file.read).to include('openjdk version "1.8.0_252"')
-    end
-  end
-
   [
     { java: '8', maven: ['3.6.3', '3.5.4', '3.3.9', '3.2.5'] },
     { java: '11', maven: ['3.6.3', '3.5.4', '3.3.9', '3.2.5'] }
diff --git a/spec/integration/python/pip_spec.rb b/spec/integration/python/pip_spec.rb
index 9911dc5..8b7d43b 100644
--- a/spec/integration/python/pip_spec.rb
+++ b/spec/integration/python/pip_spec.rb
@@ -3,6 +3,10 @@
 require 'spec_helper'
 
 RSpec.describe "pip" do
+  before do
+    system('rm -fr /opt/asdf/installs/python')
+  end
+
   context "when a project depends on the latest version of pip" do
     let(:requirements) { "sentry-sdk>=0.7.7" }
 
@@ -65,18 +69,21 @@ RSpec.describe "pip" do
   [{ version: '2', commit: '04dce91b' }, { version: '3', commit: '48e250a1' }].each do |python|
     ['1.0', '1.1', '2.0', '2.1'].each do |report_version|
       context "when generating a `#{report_version}` report using Python `#{python[:version]}`" do
+        subject { runner.scan(env: environment) }
+
         let(:url) { "https://gitlab.com/gitlab-org/security-products/tests/#{language}-#{package_manager}.git" }
         let(:language) { 'python' }
         let(:package_manager) { 'pip' }
         let(:environment) { { 'LM_REPORT_VERSION' => report_version, 'LM_PYTHON_VERSION' => python[:version] } }
         let(:expected_content) { fixture_file_content("expected/#{language}/#{python[:version]}/#{package_manager}/v#{report_version}.json").chomp }
 
-        it 'matches the expected report' do
+        before do
           runner.clone(url, branch: python[:commit])
-          report = runner.scan(env: environment)
+        end
 
-          expect(JSON.pretty_generate(report.to_h)).to eq(expected_content)
-          expect(report).to match_schema(version: report_version)
+        it 'matches the expected report' do
+          expect(JSON.pretty_generate(subject.to_h)).to eq(expected_content)
+          expect(subject).to match_schema(version: report_version)
         end
       end
     end
@@ -134,8 +141,8 @@ RSpec.describe "pip" do
       report = runner.scan(env: { 'SETUP_CMD' => 'bash custom.sh' })
 
       expect(report).to match_schema(version: '2.0')
-      expect(report.licenses_for('six')).to match_array(["MIT"])
       expect(report.dependency_names).to contain_exactly('six')
+      expect(report.licenses_for('six')).to match_array(["MIT"])
     end
   end
 
@@ -187,46 +194,4 @@ RSpec.describe "pip" do
       expect(report.licenses_for('requests')).to match_array(['Apache-2.0'])
     end
   end
-
-  context "when specifying the version of Python using environment variables" do
-    let(:output_file) { Pathname.new(runner.project_path.join('output.txt')) }
-
-    before do
-      runner.add_file('custom.sh') do
-        <<~SCRIPT
-          #!/bin/bash -l
-
-          python --version &> '#{output_file}'
-        SCRIPT
-      end
-    end
-
-    it 'prioritizes `LM_PYTHON_VERSION` over the `ASDF_PYTHON_VERSION`' do
-      runner.scan(env: {
-        'ASDF_PYTHON_VERSION' => '3.8.2',
-        'LM_PYTHON_VERSION' => '2.7.18',
-        'SETUP_CMD' => 'bash custom.sh'
-      })
-
-      expect(output_file).to exist
-      expect(output_file.read).to include('2.7.18')
-    end
-
-    it 'reads the ASDF_PYTHON_VERSION' do
-      runner.scan(env: {
-        'ASDF_PYTHON_VERSION' => '3.8.2',
-        'SETUP_CMD' => 'bash custom.sh'
-      })
-
-      expect(output_file).to exist
-      expect(output_file.read).to include('3.8.2')
-    end
-
-    it 'defaults to Python 3' do
-      runner.scan(env: { 'SETUP_CMD' => 'bash custom.sh' })
-
-      expect(output_file).to exist
-      expect(output_file.read).to include('3.8.2')
-    end
-  end
 end
diff --git a/spec/integration/python/pipenv_spec.rb b/spec/integration/python/pipenv_spec.rb
index cd20522..fad3edf 100644
--- a/spec/integration/python/pipenv_spec.rb
+++ b/spec/integration/python/pipenv_spec.rb
@@ -7,6 +7,10 @@ RSpec.describe "pipenv" do
 
   let(:env) { {} }
 
+  before do
+    system('rm -fr /opt/asdf/installs/python')
+  end
+
   include_examples "each report version", "python", "pipenv", "pip-file-lock"
 
   context "when a project depends on a version 6 Pipfile.lock" do
diff --git a/spec/integration/ruby/bundler_spec.rb b/spec/integration/ruby/bundler_spec.rb
index 6cb5543..1c0e472 100644
--- a/spec/integration/ruby/bundler_spec.rb
+++ b/spec/integration/ruby/bundler_spec.rb
@@ -7,6 +7,10 @@ RSpec.describe "bundler" do
 
   let(:env) { {} }
 
+  before do
+    system('rm -fr /opt/asdf/installs/ruby')
+  end
+
   include_examples "each report version", "ruby", "bundler"
 
   context "when the project depends on an older version of ruby specified in a `.ruby-version` file" do
@@ -89,6 +93,19 @@ RSpec.describe "bundler" do
     end
   end
 
+  context "when scanning the `gitlab-runner` project" do
+    before do
+      runner.clone('https://gitlab.com/gitlab-org/gitlab-runner.git')
+    end
+
+    specify do
+      expect(subject).to match_schema
+      expect(subject[:licenses]).not_to be_empty
+      expect(subject[:dependencies]).not_to be_empty
+      expect(subject.dependency_names).to include('gitlab.com/gitlab-org/gitlab-terminal')
+    end
+  end
+
   context "when fetching dependencies from a custom registry" do
     before do
       add_host('rubygems.test', '127.0.0.1')
diff --git a/spec/support/shared.rb b/spec/support/shared.rb
index 298d85d..28eb8c3 100644
--- a/spec/support/shared.rb
+++ b/spec/support/shared.rb
@@ -3,6 +3,8 @@
 RSpec.shared_examples "each report version" do |language, package_manager, branch = 'master'|
   ['1.0', '1.1', '2.0', '2.1'].each do |version|
     context "when generating a `#{version}` report for #{package_manager}" do
+      subject { runner.scan(env: { 'LM_REPORT_VERSION' => version }) }
+
       let(:url) { "https://gitlab.com/gitlab-org/security-products/tests/#{language}-#{package_manager}.git" }
       let(:expected_content) { JSON.parse(fixture_file_content("expected/#{language}/#{package_manager}/v#{version}.json")) }
 
@@ -11,10 +13,8 @@ RSpec.shared_examples "each report version" do |language, package_manager, branc
       end
 
       it 'matches the expected report' do
-        actual = runner.scan(env: { 'LM_REPORT_VERSION' => version })
-
-        expect(JSON.pretty_generate(actual.to_h)).to eq(JSON.pretty_generate(expected_content))
-        expect(actual).to match_schema(version: version)
+        expect(JSON.pretty_generate(subject.to_h)).to eq(JSON.pretty_generate(expected_content))
+        expect(subject).to match_schema(version: version)
       end
     end
   end
diff --git a/spec/unit/license_finder/bundler_spec.rb b/spec/unit/license_finder/bundler_spec.rb
index 5458892..84edde2 100644
--- a/spec/unit/license_finder/bundler_spec.rb
+++ b/spec/unit/license_finder/bundler_spec.rb
@@ -1,26 +1,28 @@
+# frozen_string_literal: true
+
 require 'spec_helper'
 
 RSpec.describe LicenseFinder::Bundler do
+  let(:package_manager) { described_class.new(options) }
+  let(:options) { { ignored_groups: [], project_path: project.project_path } }
+  let(:project) { ProjectHelper.new }
+
+  before do
+    project.mount(dir: project_fixture)
+  end
+
+  after do
+    project.cleanup
+  end
+
   describe "#current_packages" do
     subject do
       project.chdir do
-        bundler.prepare
-        bundler.current_packages
+        package_manager.prepare
+        package_manager.current_packages
       end
     end
 
-    let(:bundler) { described_class.new(options) }
-    let(:options) { { ignored_groups: [], project_path: project.project_path } }
-    let(:project) { ProjectHelper.new }
-
-    before do
-      project.mount(dir: project_fixture)
-    end
-
-    after do
-      project.cleanup
-    end
-
     context "when scanning a v2.1 bundler project" do
       let(:project_fixture) { fixture_file('ruby/bundler-v2.1') }
 
@@ -45,4 +47,32 @@ RSpec.describe LicenseFinder::Bundler do
       specify { expect(subject.map(&:name)).to include("saml-kit") }
     end
   end
+
+  describe "#ruby_version" do
+    subject { package_manager.send(:ruby_version) }
+
+    context "when the version of ruby is specified in the Gemfile" do
+      let(:project_fixture) { fixture_file('ruby/bundler/ruby-2.4.9') }
+
+      specify { expect(subject).to eql('2.4.9') }
+    end
+
+    context "when the version of ruby is specified in a .ruby-version file" do
+      let(:project_fixture) { fixture_file('ruby/bundler-ruby-2.4.9-no-lockfile') }
+
+      specify { expect(subject).to eql('2.4.9') }
+    end
+
+    context "when the version of ruby is specified in a .tool-versions file" do
+      let(:project_fixture) { fixture_file('ruby/bundler/ruby-2.6.0-tool-versions') }
+
+      specify { expect(subject).to eql('2.6.0') }
+    end
+
+    context "when a ruby is not specified it uses the default version" do
+      let(:project_fixture) { fixture_file('ruby/bundler-v2.1') }
+
+      specify { expect(subject).to eql('2.6.6') }
+    end
+  end
 end
diff --git a/spec/unit/license_finder/dotnet_spec.rb b/spec/unit/license_finder/dotnet_spec.rb
new file mode 100644
index 0000000..144d29e
--- /dev/null
+++ b/spec/unit/license_finder/dotnet_spec.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe LicenseFinder::Dotnet do
+  let(:package_manager) { described_class.new(options) }
+  let(:options) { { ignored_groups: [], project_path: project.project_path } }
+  let(:project) { ProjectHelper.new }
+
+  before do
+    project.mount(dir: project_fixture)
+  end
+
+  after do
+    project.cleanup
+  end
+
+  describe "#dotnet_version" do
+    subject { package_manager.dotnet_version }
+
+    context "when the version of dotnet is specified in a .tool-versions file" do
+      let(:project_fixture) { fixture_file('dotnet/nuget-csproj') }
+
+      before do
+        project.add_file('.tool-versions', 'dotnet-core 3.1.301')
+      end
+
+      specify { expect(subject).to eql('3.1.301') }
+    end
+
+    context "when a nodejs version is not specified" do
+      let(:project_fixture) { fixture_file('dotnet/nuget-csproj') }
+
+      specify { expect(subject).to eql('3.1.302') }
+    end
+  end
+end
diff --git a/spec/unit/license_finder/gradle_spec.rb b/spec/unit/license_finder/gradle_spec.rb
new file mode 100644
index 0000000..18c58d7
--- /dev/null
+++ b/spec/unit/license_finder/gradle_spec.rb
@@ -0,0 +1,65 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe LicenseFinder::Gradle do
+  let(:package_manager) { described_class.new(options) }
+  let(:options) { { ignored_groups: [], project_path: project.project_path } }
+  let(:project) { ProjectHelper.new }
+  let(:project_fixture) { fixture_file('java/gradle/java-8') }
+
+  before do
+    project.mount(dir: project_fixture)
+  end
+
+  after do
+    project.cleanup
+  end
+
+  describe "#java_version" do
+    subject { package_manager.send(:java_version, env: env) }
+
+    let(:env) { {} }
+
+    context "when the version is specified in a .tool-versions file" do
+      let(:project_fixture) { fixture_file('java/maven/tool-versions') }
+
+      specify { expect(subject).to eql('tool-versions') }
+    end
+
+    context "when the version is specified in a .java-version file" do
+      let(:project_fixture) { fixture_file('java/maven/java-version') }
+
+      specify { expect(subject).to eql('java-version') }
+    end
+
+    context "when the version is specified via a ASDF_JAVA_VERSION environment variable" do
+      let(:env) { { "ASDF_JAVA_VERSION" => 'adopt-openjdk-11' } }
+
+      specify { expect(subject).to eql('adoptopenjdk-11') }
+    end
+
+    %w[8 11].each do |java_version|
+      context "when the version is specified via a LM_JAVA_VERSION (#{java_version}) environment variable" do
+        let(:env) { { "LM_JAVA_VERSION" => java_version } }
+
+        specify { expect(subject).to eql(java_version) }
+      end
+    end
+
+    context "when LM_JAVA_VERSION and ASDF_JAVA_VERSION is provided" do
+      let(:env) do
+        {
+          'ASDF_JAVA_VERSION' => 'adopt-openjdk-11',
+          'LM_JAVA_VERSION' => '8'
+        }
+      end
+
+      specify { expect(subject).to eql('8') }
+    end
+
+    context 'when a custom Java version is not specified' do
+      specify { expect(subject).to eql('8') }
+    end
+  end
+end
diff --git a/spec/unit/license_finder/maven_spec.rb b/spec/unit/license_finder/maven_spec.rb
new file mode 100644
index 0000000..737b707
--- /dev/null
+++ b/spec/unit/license_finder/maven_spec.rb
@@ -0,0 +1,65 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe LicenseFinder::Maven do
+  let(:package_manager) { described_class.new(options) }
+  let(:options) { { ignored_groups: [], project_path: project.project_path } }
+  let(:project) { ProjectHelper.new }
+  let(:project_fixture) { fixture_file('java/maven/simple') }
+
+  before do
+    project.mount(dir: project_fixture)
+  end
+
+  after do
+    project.cleanup
+  end
+
+  describe "#java_version" do
+    subject { package_manager.send(:java_version, env: env) }
+
+    let(:env) { {} }
+
+    context "when the version is specified in a .tool-versions file" do
+      let(:project_fixture) { fixture_file('java/maven/tool-versions') }
+
+      specify { expect(subject).to eql('tool-versions') }
+    end
+
+    context "when the version is specified in a .java-version file" do
+      let(:project_fixture) { fixture_file('java/maven/java-version') }
+
+      specify { expect(subject).to eql('java-version') }
+    end
+
+    context "when the version is specified via a ASDF_JAVA_VERSION environment variable" do
+      let(:env) { { "ASDF_JAVA_VERSION" => 'adopt-openjdk-11' } }
+
+      specify { expect(subject).to eql('adoptopenjdk-11') }
+    end
+
+    %w[8 11].each do |java_version|
+      context "when the version is specified via a LM_JAVA_VERSION (#{java_version}) environment variable" do
+        let(:env) { { "LM_JAVA_VERSION" => java_version } }
+
+        specify { expect(subject).to eql(java_version) }
+      end
+    end
+
+    context "when LM_JAVA_VERSION and ASDF_JAVA_VERSION is provided" do
+      let(:env) do
+        {
+          'ASDF_JAVA_VERSION' => 'adopt-openjdk-11',
+          'LM_JAVA_VERSION' => '8'
+        }
+      end
+
+      specify { expect(subject).to eql('8') }
+    end
+
+    context 'when a custom Java version is not specified' do
+      specify { expect(subject).to eql('8') }
+    end
+  end
+end
diff --git a/spec/unit/license_finder/pip_spec.rb b/spec/unit/license_finder/pip_spec.rb
new file mode 100644
index 0000000..8a5efbc
--- /dev/null
+++ b/spec/unit/license_finder/pip_spec.rb
@@ -0,0 +1,69 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe LicenseFinder::Pip do
+  let(:package_manager) { described_class.new(options) }
+  let(:options) { { ignored_groups: [], project_path: project.project_path } }
+  let(:project) { ProjectHelper.new }
+  let(:project_fixture) { fixture_file('python/pip/requirements') }
+
+  before do
+    project.mount(dir: project_fixture)
+  end
+
+  after do
+    project.cleanup
+  end
+
+  describe "#python_version" do
+    subject { package_manager.send(:python_version, env: env) }
+
+    let(:env) { {} }
+
+    context "when the version is specified in a .tool-versions file" do
+      before do
+        project.add_file(".tool-versions", "python 3.8.1")
+      end
+
+      specify { expect(subject).to eql('3.8.5') }
+    end
+
+    context "when the version is specified in a .python-version file" do
+      before do
+        project.add_file(".python-version", "3.8.0")
+      end
+
+      specify { expect(subject).to eql('3.8.5') }
+    end
+
+    context "when the version is specified via a ASDF_PYTHON_VERSION environment variable" do
+      let(:env) { { "ASDF_PYTHON_VERSION" => '3.8.1' } }
+
+      specify { expect(subject).to eql('3.8.5') }
+    end
+
+    [['2', '2.7.18'], ['3', '3.8.5']].each do |(major, version)|
+      context "when the version is specified via a LM_PYTHON_VERSION (#{major}) environment variable" do
+        let(:env) { { "LM_PYTHON_VERSION" => major } }
+
+        specify { expect(subject).to eql(version) }
+      end
+    end
+
+    context "when LM_PYTHON_VERSION and ASDF_PYTHON_VERSION is provided" do
+      let(:env) do
+        {
+          'ASDF_PYTHON_VERSION' => '2.7.19',
+          'LM_PYTHON_VERSION' => '3'
+        }
+      end
+
+      specify { expect(subject).to eql('3.8.5') }
+    end
+
+    context 'when a custom Python version is not specified' do
+      specify { expect(subject).to eql('3.8.5') }
+    end
+  end
+end
diff --git a/spec/unit/license_finder/pipenv_spec.rb b/spec/unit/license_finder/pipenv_spec.rb
new file mode 100644
index 0000000..7971df5
--- /dev/null
+++ b/spec/unit/license_finder/pipenv_spec.rb
@@ -0,0 +1,75 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe LicenseFinder::Pipenv do
+  let(:package_manager) { described_class.new(options) }
+  let(:options) { { ignored_groups: [], project_path: project.project_path } }
+  let(:project) { ProjectHelper.new }
+  let(:project_fixture) { fixture_file('python/pipenv/simple') }
+
+  before do
+    project.mount(dir: project_fixture)
+  end
+
+  after do
+    project.cleanup
+  end
+
+  describe "#python_version" do
+    subject { package_manager.send(:python_version, env: env) }
+
+    let(:env) { {} }
+
+    context "when the version is specified in a .tool-versions file" do
+      before do
+        project.add_file(".tool-versions", "python 3.8.1")
+      end
+
+      specify { expect(subject).to eql('3.8.5') }
+    end
+
+    context "when the version is specified in a .python-version file" do
+      before do
+        project.add_file(".python-version", "3.8.0")
+      end
+
+      specify { expect(subject).to eql('3.8.5') }
+    end
+
+    context "when the version is specified via a ASDF_PYTHON_VERSION environment variable" do
+      let(:env) { { "ASDF_PYTHON_VERSION" => '3.8.1' } }
+
+      specify { expect(subject).to eql('3.8.5') }
+    end
+
+    [['2', '2.7.18'], ['3', '3.8.5']].each do |(major, version)|
+      context "when the version is specified via a LM_PYTHON_VERSION (#{major}) environment variable" do
+        let(:env) { { "LM_PYTHON_VERSION" => major } }
+
+        specify { expect(subject).to eql(version) }
+      end
+    end
+
+    context "when LM_PYTHON_VERSION and ASDF_PYTHON_VERSION is provided" do
+      let(:env) do
+        {
+          'ASDF_PYTHON_VERSION' => '2.7.19',
+          'LM_PYTHON_VERSION' => '3'
+        }
+      end
+
+      specify { expect(subject).to start_with('3.8') }
+    end
+
+    context 'when the version is specified in the Pipfile.lock' do
+      let(:project_fixture) { fixture_file('python/pipenv/specific-python-version') }
+
+      specify { expect(subject).to start_with('3.4') }
+    end
+
+    context 'when a custom Python version is not specified' do
+      specify { expect(subject).to eql('3.8.5') }
+    end
+  end
+end
diff --git a/spec/unit/license_finder/yarn_spec.rb b/spec/unit/license_finder/yarn_spec.rb
new file mode 100644
index 0000000..7062ea3
--- /dev/null
+++ b/spec/unit/license_finder/yarn_spec.rb
@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe LicenseFinder::Yarn do
+  let(:package_manager) { described_class.new(options) }
+  let(:options) { { ignored_groups: [], project_path: project.project_path } }
+  let(:project) { ProjectHelper.new }
+
+  before do
+    project.mount(dir: project_fixture)
+  end
+
+  after do
+    project.cleanup
+  end
+
+  describe "#nodejs_version" do
+    subject { package_manager.send(:nodejs_version) }
+
+    context "when the version of nodejs is specified in a .tool-versions file" do
+      let(:project_fixture) { fixture_file('js/10.21.0-tool-versions') }
+
+      specify { expect(subject).to eql('10.21.0') }
+    end
+
+    context "when a nodejs version is not specified" do
+      let(:project_fixture) { fixture_file('js/yarn/single-declared-dependency') }
+
+      specify { expect(subject).to eql('12.18.2') }
+    end
+  end
+end