CDP: support remote debugging in different environment

From investigation by @ko1-san, the path to set breakpoints seems to be sent in "url" field when debugging in different environment such as WSL(running debuggee) and Windows(running Chrome DevTools). I supported "url" field in this PR.

Author: ono-max

lib/debug/server_cdp.rb

@@ -12,7 +12,7 @@
 
 module DEBUGGER__
   module UI_CDP
-    SHOW_PROTOCOL = ENV['RUBY_DEBUG_CDP_SHOW_PROTOCOL'] == '1'
+    SHOW_PROTOCOL = true
 
     class UnsupportedError < StandardError; end
     class NotFoundChromeEndpointError < StandardError; end
@@ -558,35 +558,31 @@ def process
         when 'Debugger.setBreakpointByUrl'
           line = req.dig('params', 'lineNumber')
           if regexp = req.dig('params', 'urlRegex')
-            path = regexp.match(/(.*)\|/)[1].gsub("\\", "")
-            cond = req.dig('params', 'condition')
-            src = get_source_code path
-            end_line = src.lines.count
-            line = end_line  if line > end_line
             b_id = "1:#{line}:#{regexp}"
-            if cond != ''
-              SESSION.add_line_breakpoint(path, line + 1, cond: cond)
-            else
-              SESSION.add_line_breakpoint(path, line + 1)
-            end
             bps[b_id] = bps.size
-            # Because we need to return scriptId, responses are returned in SESSION thread.
-            req['params']['scriptId'] = path
-            req['params']['lineNumber'] = line
-            req['params']['breakpointId'] = b_id
-            @q_msg << req
+            path = regexp.match(/(.*)\|/)[1].gsub("\\", "")
+            add_line_breakpoint(req, b_id, path)
           elsif url = req.dig('params', 'url')
             b_id = "#{line}:#{url}"
-            send_response req,
-                          breakpointId: b_id,
-                          locations: []
-          elsif hash = req.dig('params', 'scriptHash')
-            b_id = "#{line}:#{hash}"
-            send_response req,
-                          breakpointId: b_id,
-                          locations: []
+            # When breakpoints are set in Script snippet, non-existent path such as "snippet:///Script%20snippet%20%231" sent.
+            # That's why we need to check it here.
+            if File.exist? url
+              bps[b_id] = bps.size
+              add_line_breakpoint(req, b_id, url)
+            else
+              send_response req,
+                            breakpointId: b_id,
+                            locations: []
+            end            
           else
-            raise 'Unsupported'
+            if hash = req.dig('params', 'scriptHash')
+              b_id = "#{line}:#{hash}"
+              send_response req,
+                            breakpointId: b_id,
+                            locations: []
+            else
+              raise 'Unsupported'
+            end
           end
         when 'Debugger.removeBreakpoint'
           b_id = req.dig('params', 'breakpointId')
@@ -625,6 +621,24 @@ def process
       @q_msg << 'continue'
     end
 
+    def add_line_breakpoint req, b_id, path
+      cond = req.dig('params', 'condition')
+      line = req.dig('params', 'lineNumber')
+      src = get_source_code path
+      end_line = src.lines.count
+      line = end_line  if line > end_line
+      if cond != ''
+        SESSION.add_line_breakpoint(path, line + 1, cond: cond)
+      else
+        SESSION.add_line_breakpoint(path, line + 1)
+      end
+      # Because we need to return scriptId, responses are returned in SESSION thread.
+      req['params']['scriptId'] = path
+      req['params']['lineNumber'] = line
+      req['params']['breakpointId'] = b_id
+      @q_msg << req
+    end
+
     def del_bp bps, k
       return bps unless idx = bps[k]