From 335f1daddcfc17e02329a4ff8c02455b0bb448ee Mon Sep 17 00:00:00 2001
From: Oleg Pudeyev <code@olegp.name>
Date: Wed, 24 Sep 2025 10:59:59 -0400
Subject: [PATCH 1/2] permit line no & method name at the same time

---
 lib/datadog/di/probe.rb | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/lib/datadog/di/probe.rb b/lib/datadog/di/probe.rb
index ca4088a60da..e235da3e388 100644
--- a/lib/datadog/di/probe.rb
+++ b/lib/datadog/di/probe.rb
@@ -46,6 +46,17 @@ def initialize(id:, type:,
           raise ArgumentError, "Unknown probe type: #{type}"
         end
 
+        # TODO Probe should be inferred to be a line probe if the specification
+        # contains a line number. This how Java tracer works and Go tracer
+        # is implementing the same behavior, and Go will have all 3 fields
+        # (file path, line number and method name) for line probes.
+        # Do not raise if line number and method name both exist - instead
+        # treat the probe as a line probe.
+        #
+        # In the future we want to provide type name and method name to line
+        # probes, so that the library can verify that the instrumented line
+        # is in the method that the frontend showed to the user when the
+        # user created the probe.
         if line_no && method_name
           raise ArgumentError, "Probe contains both line number and method name: #{id}"
         end

From 8087c658085af067ad8d71ba0ba8726563fd1f21 Mon Sep 17 00:00:00 2001
From: Oleg Pudeyev <code@olegp.name>
Date: Wed, 24 Sep 2025 11:25:24 -0400
Subject: [PATCH 2/2] implement

---
 lib/datadog/di/probe.rb       | 19 ++++++-------------
 spec/datadog/di/probe_spec.rb |  7 +++----
 2 files changed, 9 insertions(+), 17 deletions(-)

diff --git a/lib/datadog/di/probe.rb b/lib/datadog/di/probe.rb
index e235da3e388..c04e7a59d2d 100644
--- a/lib/datadog/di/probe.rb
+++ b/lib/datadog/di/probe.rb
@@ -46,7 +46,7 @@ def initialize(id:, type:,
           raise ArgumentError, "Unknown probe type: #{type}"
         end
 
-        # TODO Probe should be inferred to be a line probe if the specification
+        # Probe should be inferred to be a line probe if the specification
         # contains a line number. This how Java tracer works and Go tracer
         # is implementing the same behavior, and Go will have all 3 fields
         # (file path, line number and method name) for line probes.
@@ -57,9 +57,6 @@ def initialize(id:, type:,
         # probes, so that the library can verify that the instrumented line
         # is in the method that the frontend showed to the user when the
         # user created the probe.
-        if line_no && method_name
-          raise ArgumentError, "Probe contains both line number and method name: #{id}"
-        end
 
         if line_no && !file
           raise ArgumentError, "Probe contains line number but not file: #{id}"
@@ -69,6 +66,10 @@ def initialize(id:, type:,
           raise ArgumentError, "Partial method probe definition: #{id}"
         end
 
+        if line_no.nil? && method_name.nil?
+          raise ArgumentError, "Unhandled probe type: neither method nor line probe: #{id}"
+        end
+
         @id = id
         @type = type
         @file = file
@@ -82,14 +83,6 @@ def initialize(id:, type:,
         @max_capture_attribute_count = max_capture_attribute_count
         @condition = condition
 
-        # These checks use instance methods that have more complex logic
-        # than checking a single argument value. To avoid duplicating
-        # the logic here, use the methods and perform these checks after
-        # instance variable assignment.
-        unless method? || line?
-          raise ArgumentError, "Unhandled probe type: neither method nor line probe: #{id}"
-        end
-
         @rate_limit = rate_limit || (@capture_snapshot ? 1 : 5000)
         @rate_limiter = Datadog::Core::TokenBucket.new(@rate_limit)
 
@@ -140,7 +133,7 @@ def line?
 
       # Returns whether the probe is a method probe.
       def method?
-        !!(type_name && method_name)
+        line_no.nil?
       end
 
       # Returns the line number associated with the probe, raising
diff --git a/spec/datadog/di/probe_spec.rb b/spec/datadog/di/probe_spec.rb
index 4aa41809452..88403759bfe 100644
--- a/spec/datadog/di/probe_spec.rb
+++ b/spec/datadog/di/probe_spec.rb
@@ -89,10 +89,9 @@
           type_name: "foo", method_name: "bar", file: "baz", line_no: 4)
       end
 
-      it "raises ArgumentError" do
-        expect do
-          probe
-        end.to raise_error(ArgumentError, /both line number and method name/)
+      it "creates a line probe" do
+        expect(probe.line?).to be true
+        expect(probe.method?).to be false
       end
     end
   end