Add command to diagnose common issues

This new command, doctor, checks for common problems.
Currently, it looks for broken dynamic library links in C
extensions.

It scans all of the specifications in the bundle for .bundle files in C
extensions. If any of the dynamic libraries linked against no longer
exist, bundler will report a message to the console.

1 files changed, 61 insertions, 0 deletions

diff --git a/spec/commands/doctor_spec.rb b/spec/commands/doctor_spec.rb
new file mode 100644
index 0000000000..236138a6c8
--- /dev/null
+++ b/spec/commands/doctor_spec.rb
@@ -0,0 +1,61 @@
+# frozen_string_literal: true
+require "spec_helper"
+require "stringio"
+require "bundler/cli"
+require "bundler/cli/doctor"
+
+describe "bundle doctor" do
+  before(:each) do
+    @stdout = StringIO.new
+
+    [:error, :warn].each do |method|
+      allow(Bundler.ui).to receive(method).and_wrap_original do |m, message|
+        m.call message
+        @stdout.puts message
+      end
+    end
+  end
+
+  it "exits with no message if the installed gem has no C extensions" do
+    gemfile <<-G
+      source "file://#{gem_repo1}"
+      gem "rack"
+    G
+
+    bundle :install
+    Bundler::CLI::Doctor.new({}).run
+    expect(@stdout.string).to be_empty
+  end
+
+  it "exits with no message if the installed gem's C extension dylib breakage is fine" do
+    gemfile <<-G
+      source "file://#{gem_repo1}"
+      gem "rack"
+    G
+
+    bundle :install
+    doctor = Bundler::CLI::Doctor.new({})
+    expect(doctor).to receive(:bundles_for_gem).exactly(2).times.and_return ["/path/to/rack/rack.bundle"]
+    expect(doctor).to receive(:dylibs).exactly(2).times.and_return ["/usr/lib/libSystem.dylib"]
+    allow(File).to receive(:exist?).and_call_original
+    allow(File).to receive(:exist?).with("/usr/lib/libSystem.dylib").and_return(true)
+    doctor.run
+    expect(@stdout.string).to be_empty
+  end
+
+  it "exits with a message if one of the linked libraries is missing" do
+    gemfile <<-G
+      source "file://#{gem_repo1}"
+      gem "rack"
+    G
+
+    bundle :install
+    doctor = Bundler::CLI::Doctor.new({})
+    expect(doctor).to receive(:bundles_for_gem).exactly(2).times.and_return ["/path/to/rack/rack.bundle"]
+    expect(doctor).to receive(:dylibs).exactly(2).times.and_return ["/usr/local/opt/icu4c/lib/libicui18n.57.1.dylib"]
+    allow(File).to receive(:exist?).and_call_original
+    allow(File).to receive(:exist?).with("/usr/local/opt/icu4c/lib/libicui18n.57.1.dylib").and_return(false)
+    expect { doctor.run }.to raise_error SystemExit
+    expect(@stdout.string).to include("libicui18n.57.1.dylib")
+  end
+end