DEBUG-2334 do not try to install pending probes on eval'd code

lib/datadog/di/code_tracker.rb

@@ -78,10 +78,11 @@ def start
               registry_lock.synchronize do
                 registry[path] = tp.instruction_sequence
               end
-            end
-
-            DI.current_component&.probe_manager&.install_pending_line_probes(path)
 
+              # Also, pending line probes should only be installed for
+              # non-eval'd code.
+              DI.current_component&.probe_manager&.install_pending_line_probes(path)
+            end
           # Since this method normally is called from customer applications,
           # rescue any exceptions that might not be handled to not break said
           # customer applications.

lib/datadog/di/probe.rb

@@ -161,6 +161,9 @@ def location
       # If file is not an absolute path, the path matches if the file is its suffix,
       # at a path component boundary.
       def file_matches?(path)
+        if path.nil?
+          raise ArgumentError, "Cannot match against a nil path"
+        end
         unless file
           raise ArgumentError, "Probe does not have a file to match against"
         end

lib/datadog/di/probe_manager.rb

@@ -206,6 +206,9 @@ def remove_other_probes(probe_ids)
       # point, which is invoked for each required or loaded file
       # (and also for eval'd code, but those invocations are filtered out).
       def install_pending_line_probes(path)
+        if path.nil?
+          raise ArgumentError, "path must not be nil"
+        end
         @lock.synchronize do
           @pending_probes.values.each do |probe|
             if probe.line?

lib/datadog/di/utils.rb

@@ -12,6 +12,13 @@ module Utils
       # If suffix is not an absolute path, the path matches if its suffix is
       # the provided suffix, at a path component boundary.
       module_function def path_matches_suffix?(path, suffix)
+        if path.nil?
+          raise ArgumentError, "nil path passed"
+        end
+        if suffix.nil?
+          raise ArgumentError, "nil suffix passed"
+        end
+
         if suffix.start_with?('/')
           path == suffix
         else

spec/datadog/di/code_tracker_pending_load.rb

@@ -0,0 +1 @@
+# Nothing

spec/datadog/di/code_tracker_pending_require.rb

@@ -0,0 +1 @@
+# Nothing

spec/datadog/di/code_tracker_spec.rb

@@ -4,10 +4,24 @@
 RSpec.describe Datadog::DI::CodeTracker do
   di_test
 
+  before(:all) do
+    Datadog::DI.deactivate_tracking!
+  end
+
   let(:tracker) do
     described_class.new
   end
 
+  shared_context 'when code tracker is running' do
+    before do
+      tracker.start
+    end
+
+    after do
+      tracker.stop
+    end
+  end
+
   describe "#start" do
     after do
       tracker.stop
@@ -90,13 +104,7 @@
 
   describe "#active?" do
     context "when started" do
-      before do
-        tracker.start
-      end
-
-      after do
-        tracker.stop
-      end
+      include_context 'when code tracker is running'
 
       it "is true" do
         expect(tracker.active?).to be true
@@ -115,6 +123,57 @@
     end
   end
 
+  describe 'line probe installation' do
+    let(:component) do
+      instance_double(Datadog::DI::Component).tap do |component|
+        expect(component).to receive(:probe_manager).and_return(probe_manager)
+      end
+    end
+
+    let(:probe_manager) do
+      instance_double(Datadog::DI::ProbeManager)
+    end
+
+    context 'when started' do
+      include_context 'when code tracker is running'
+
+      context 'when a file is required' do
+        it 'requests to install pending line probes' do
+          expect(Datadog::DI).to receive(:current_component).and_return(component)
+          expect(probe_manager).to receive(:install_pending_line_probes) do |path|
+            # Should be an absolute path
+            expect(path).to start_with('/')
+            expect(File.basename(path)).to eq('code_tracker_pending_require.rb')
+          end
+          require_relative 'code_tracker_pending_require'
+        end
+      end
+
+      context 'when a file is loaded' do
+        it 'requests to install pending line probes' do
+          expect(Datadog::DI).to receive(:current_component).and_return(component)
+          expect(probe_manager).to receive(:install_pending_line_probes) do |path|
+            # Should be an absolute path
+            expect(path).to start_with('/')
+            expect(File.basename(path)).to eq('code_tracker_pending_load.rb')
+          end
+          load File.join(File.dirname(__FILE__), 'code_tracker_pending_load.rb')
+        end
+      end
+
+      context "when Ruby code is eval'd" do
+        it 'requests to install pending line probes' do
+          # Matchers can be lazily loaded, force all code to be loaded here.
+          expect(4).to eq(4)
+
+          expect(Datadog::DI).not_to receive(:current_component)
+          expect(probe_manager).not_to receive(:install_pending_line_probes)
+          expect(eval('2 + 2')).to eq(4) # rubocop:disable Style/EvalWithLocation
+        end
+      end
+    end
+  end
+
   describe "#iseqs_for_path_suffix" do
     around do |example|
       tracker.start