Improve behavior of :test_mode/:dsn

lib/sentry.ex

@@ -327,6 +327,10 @@ defmodule Sentry do
         LoggerUtils.log("Cannot report event without message or exception: #{inspect(event)}")
         :ignored
 
+      # If we're in test mode, let's send the event down the pipeline anyway.
+      Config.test_mode?() ->
+        Client.send_event(event, opts)
+
       !Config.dsn() ->
         :ignored
 

lib/sentry/config.ex

@@ -64,6 +64,8 @@ defmodule Sentry.Config do
       doc: """
       The DSN for your Sentry project. If this is not set, Sentry will not be enabled.
       If the `SENTRY_DSN` environment variable is set, it will be used as the default value.
+      If `:test_mode` is `true`, the `:dsn` option is sometimes ignored; see `Sentry.Test`
+      for more information.
       """
     ],
     environment_name: [
@@ -200,7 +202,8 @@ defmodule Sentry.Config do
       doc: """
       Whether to enable *test mode*. When test mode is enabled, the SDK will check whether
       there is a process **collecting events** and avoid sending those events if that's the
-      case. This is useful for testing. See `Sentry.Test`.
+      case. This is useful for testing—see `Sentry.Test`. `:test_mode` works in tandem
+      with `:dsn`; this is described in detail in `Sentry.Test`.
       """
     ],
     integrations: [

lib/sentry/test.ex

@@ -5,12 +5,32 @@ defmodule Sentry.Test do
   ## Usage
 
   This module is based on **collecting** reported events and then retrieving
-  them to perform assertions. You can start collecting events from a process
+  them to perform assertions. The functionality here is only available if the
+  `:test_mode` configuration option is set to `true`—see
+  [`Sentry`'s configuration section](sentry.html#module-configuration).
+  You can start collecting events from a process
   by calling `start_collecting_sentry_reports/0`. Then, you can use Sentry
   as normal and report events (through functions such as `Sentry.capture_message/1`
   or `Sentry.capture_exception/1`). Finally, you can retrieve the collected events
   by calling `pop_sentry_reports/0`.
 
+  > #### Test Mode and DSN {: .info}
+  >
+  > If `:test_mode` is `true`, the `:dsn` option behaves differently. When `:dsn` is
+  > not set or `nil` and you're collecting events, you'll still be able to collect
+  > events—even if under normal circumstances a missing `:dsn` means events don't get
+  > reported. If `:dsn` is `nil` and you're not collecting events, the event is simply
+  > ignored. See the table below for a summary for this behavior.
+
+  | `:test_mode` | `:dsn` | Collecting events? | Behavior                                               |
+  |--------------|--------|--------------------|--------------------------------------------------------|
+  | `true`       | `nil`  | yes                | Event is collected                                     |
+  | `true`       | `nil`  | no                 | Event is ignored (silently)                            |
+  | `true`       | set    | yes                | Event is collected                                     |
+  | `true`       | set    | no                 | Makes HTTP request to configured DSN (could be Bypass) |
+  | `false`      | `nil`  | irrelevant         | Ignores event                                          |
+  | `false`      | set    | irrelevant         | Makes HTTP request to configured DSN (could be Bypass) |
+
   ## Examples
 
   Let's imagine writing a test using the functions in this module. First, we need to
@@ -64,6 +84,7 @@ defmodule Sentry.Test do
   @spec maybe_collect(Sentry.Event.t()) :: :collected | :not_collecting
   def maybe_collect(%Sentry.Event{} = event) do
     if Sentry.Config.test_mode?() do
+      dsn_set? = not is_nil(Sentry.Config.dsn())
       ensure_ownership_server_started()
 
       case NimbleOwnership.fetch_owner(@server, callers(), @key) do
@@ -81,8 +102,13 @@ defmodule Sentry.Test do
               raise ArgumentError, "cannot collect Sentry reports: #{Exception.message(error)}"
           end
 
-        :error ->
+        :error when dsn_set? ->
           :not_collecting
+
+        # If the :dsn option is not set and we didn't capture the event, it's alright,
+        # we can just swallow it.
+        :error ->
+          :collected
       end
     else
       :not_collecting

test/sentry_test.exs

@@ -119,12 +119,18 @@ defmodule SentryTest do
     assert logged_count == 2
   end
 
-  test "does not send events if :dsn is not configured or nil" do
-    put_test_config(dsn: nil)
+  test "does not send events if :dsn is not configured or nil (if not in test mode)" do
+    put_test_config(dsn: nil, test_mode: false)
     event = Sentry.Event.transform_exception(%RuntimeError{message: "oops"}, [])
     assert :ignored = Sentry.send_event(event)
   end
 
+  test "if in test mode, swallows events if the :dsn is nil" do
+    put_test_config(dsn: nil, test_mode: true)
+    event = Sentry.Event.transform_exception(%RuntimeError{message: "oops"}, [])
+    assert {:ok, ""} = Sentry.send_event(event)
+  end
+
   describe "send_check_in/1" do
     test "posts a check-in with all the explicit arguments", %{bypass: bypass} do
       put_test_config(environment_name: "test", release: "1.3.2")