Stop warning when on eval & streaming code

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## HEAD (unreleased)
 
+- Code that does not have an associated file (eval and streamed) no longer produce a warning saying that the file could not be found. To produce a warning with these code types run with DEBUG=1 environment variable. (https://github.com/zombocom/dead_end/pull/143)
 - [Breaking] Lazy load DeadEnd internals only if there is a Syntax error. Use `require "dead_end"; require "dead_end/api"` to load eagerly all internals. Otherwise `require "dead_end"` will set up an autoload for the first time the DeadEnd module is used in code. This should only happen on a syntax error. (https://github.com/zombocom/dead_end/pull/142)
 - Monkeypatch `SyntaxError#detailed_message` in Ruby 3.2+ instead of `require`, `load`, and `require_relative` (https://github.com/zombocom/dead_end/pull/139)
 

lib/dead_end/pathname_from_message.rb

@@ -13,6 +13,8 @@ module DeadEnd
   #    # => "/tmp/scratch.rb"
   #
   class PathnameFromMessage
+    EVAL_RE = /^\(eval\):\d+/
+    STREAMING_RE = /^-:\d+/
     attr_reader :name
 
     def initialize(message, io: $stderr)
@@ -24,14 +26,20 @@ def initialize(message, io: $stderr)
     end
 
     def call
-      until stop?
-        @guess << @parts.shift
-        @name = Pathname(@guess.join(":"))
-      end
+      if skip_missing_file_name?
+        if ENV["DEBUG"]
+          @io.puts "DeadEnd: Could not find filename from #{@line.inspect}"
+        end
+      else
+        until stop?
+          @guess << @parts.shift
+          @name = Pathname(@guess.join(":"))
+        end
 
-      if @parts.empty?
-        @io.puts "DeadEnd: Could not find filename from #{@line.inspect}"
-        @name = nil
+        if @parts.empty?
+          @io.puts "DeadEnd: Could not find filename from #{@line.inspect}"
+          @name = nil
+        end
       end
 
       self
@@ -43,5 +51,9 @@ def stop?
 
       @name&.exist?
     end
+
+    def skip_missing_file_name?
+      @line.match?(EVAL_RE) || @line.match?(STREAMING_RE)
+    end
   end
 end

spec/integration/ruby_command_line_spec.rb

@@ -146,5 +146,24 @@ class Dog
         expect(out).to include("DeadEnd is NOT loaded").once
       end
     end
+
+    it "ignores eval" do
+      Dir.mktmpdir do |dir|
+        tmpdir = Pathname(dir)
+        script = tmpdir.join("script.rb")
+        script.write <<~'EOM'
+          $stderr = STDOUT
+          eval("def lol")
+        EOM
+
+        out = `ruby -I#{lib_dir} -rdead_end #{script} 2>&1`
+
+        expect($?.success?).to be_falsey
+        expect(out).to include("(eval):1")
+
+        expect(out).to_not include("DeadEnd")
+        expect(out).to_not include("Could not find filename")
+      end
+    end
   end
 end

spec/unit/pathname_from_message_spec.rb

@@ -22,6 +22,8 @@ module DeadEnd
         dir = Pathname(dir)
 
         file = dir.join("scratch.rb")
+        # No touch, file does not exist
+        expect(file.exist?).to be_falsey
 
         message = "#{file}:2:in `require_relative': /private/tmp/bad.rb:1: syntax error, unexpected `end' (SyntaxError)"
         io = StringIO.new
@@ -31,5 +33,24 @@ module DeadEnd
         expect(file).to be_falsey
       end
     end
+
+    it "does not output error message on syntax error inside of an (eval)" do
+      message = "(eval):1: invalid multibyte char (UTF-8) (SyntaxError)\n"
+      io = StringIO.new
+      file = PathnameFromMessage.new(message, io: io).call.name
+
+      expect(io.string).to eq("")
+      expect(file).to be_falsey
+    end
+
+    it "does not output error message on syntax error inside of streamed code" do
+      # An example of streamed code is: $ echo "def foo" | ruby
+      message = "-:1: syntax error, unexpected end-of-input\n"
+      io = StringIO.new
+      file = PathnameFromMessage.new(message, io: io).call.name
+
+      expect(io.string).to eq("")
+      expect(file).to be_falsey
+    end
   end
 end