Debugger: add dedicated message for VSCode watch

Processing VSCode watches skips waitForResolvingPendingBreakpoints
(previously having multiple watches in VSC would call this when
processing the first watch, which would process pending messages while
trying to wait for break point changes while in eval mode (not in
waiting mode) and cause and Invalid message error and the closure of the
debgger connection when hitting the second watch message)

Allow '*.mjs' files in the python debugger

Add watches to the python debugger, add test

Signed-off-by: Máté Tokodi mate.tokodi@szteszoftver.hu

Author: matetokodi

src/debugger/Debugger.cpp

@@ -189,7 +189,7 @@ void DebuggerRemote::parseCompleted(String* source, String* srcName, size_t orig
 
     sendType(ESCARGOT_MESSAGE_PARSE_DONE);
 
-    if (enabled() && pendingWait()) {
+    if (enabled() && pendingWait() && !m_watchEval) {
         waitForResolvingPendingBreakpoints();
     }
 }
@@ -371,9 +371,9 @@ bool DebuggerRemote::doEval(ExecutionState* state, Optional<ByteCodeBlock*> byte
     }
 
     String* str;
-    if (type == ESCARGOT_MESSAGE_EVAL_8BIT || type == ESCARGOT_MESSAGE_EVAL_WITHOUT_STOP_8BIT) {
+    if (type == ESCARGOT_MESSAGE_EVAL_8BIT || type == ESCARGOT_MESSAGE_EVAL_WITHOUT_STOP_8BIT || type == ESCARGOT_MESSAGE_WATCH_8BIT) {
         str = new Latin1String(data, size);
-    } else if (type == ESCARGOT_MESSAGE_EVAL_16BIT || type == ESCARGOT_MESSAGE_EVAL_WITHOUT_STOP_16BIT) {
+    } else if (type == ESCARGOT_MESSAGE_EVAL_16BIT || type == ESCARGOT_MESSAGE_EVAL_WITHOUT_STOP_16BIT || type == ESCARGOT_MESSAGE_WATCH_16BIT) {
         str = new UTF16String((char16_t*)data, size / 2);
     } else if (type == ESCARGOT_DEBUGGER_CLIENT_SOURCE_8BIT) {
         char* sourceNameSrc = (char*)memchr(data, '\0', size);
@@ -401,6 +401,9 @@ bool DebuggerRemote::doEval(ExecutionState* state, Optional<ByteCodeBlock*> byte
         return false;
     }
 
+    if (type == ESCARGOT_MESSAGE_WATCH_8BIT || type == ESCARGOT_MESSAGE_WATCH_16BIT) {
+        m_watchEval = true;
+    }
     m_stopState = ESCARGOT_DEBUGGER_IN_EVAL_MODE;
 
     try {
@@ -411,14 +414,15 @@ bool DebuggerRemote::doEval(ExecutionState* state, Optional<ByteCodeBlock*> byte
         } else {
             result = state->context()->globalObject()->evalLocal(*state, asValue, state->thisValue(), byteCodeBlock->m_codeBlock, true);
         }
-        type = ESCARGOT_MESSAGE_EVAL_RESULT_8BIT;
+        type = m_watchEval ? ESCARGOT_MESSAGE_WATCH_RESULT_8BIT : ESCARGOT_MESSAGE_EVAL_RESULT_8BIT;
         str = result.toStringWithoutException(*state);
     } catch (const Value& val) {
         type = ESCARGOT_MESSAGE_EVAL_FAILED_8BIT;
         str = val.toStringWithoutException(*state);
     }
 
     m_stopState = ESCARGOT_DEBUGGER_IN_WAIT_MODE;
+    m_watchEval = false;
 
     if (enabled()) {
         sendString(type, str);
@@ -923,6 +927,8 @@ bool DebuggerRemote::processEvents(ExecutionState* state, Optional<ByteCodeBlock
             m_stopState = stopState;
             return false;
         }
+        case ESCARGOT_MESSAGE_WATCH_8BIT_START:
+        case ESCARGOT_MESSAGE_WATCH_16BIT_START:
         case ESCARGOT_MESSAGE_EVAL_8BIT_START:
         case ESCARGOT_MESSAGE_EVAL_16BIT_START: {
             if ((length <= 1 + sizeof(uint32_t)) || m_stopState != ESCARGOT_DEBUGGER_IN_WAIT_MODE) {

src/debugger/Debugger.h

@@ -268,6 +268,11 @@ class DebuggerRemote : public Debugger {
         ESCARGOT_DEBUGGER_WAIT_FOR_SOURCE = 43,
         ESCARGOT_DEBUGGER_WAITING_AFTER_PENDING = 44,
         ESCARGOT_DEBUGGER_WAIT_FOR_WAIT_EXIT = 45,
+        // These four must be in the same order.
+        ESCARGOT_MESSAGE_WATCH_RESULT_8BIT = 46,
+        ESCARGOT_MESSAGE_WATCH_RESULT_8BIT_END = 47,
+        ESCARGOT_MESSAGE_WATCH_RESULT_16BIT = 48,
+        ESCARGOT_MESSAGE_WATCH_RESULT_16BIT_END = 49
     };
 
     // Messages sent by the debugger client to Escargot
@@ -301,6 +306,12 @@ class DebuggerRemote : public Debugger {
         ESCARGOT_DEBUGGER_PENDING_CONFIG = 23,
         ESCARGOT_DEBUGGER_PENDING_RESUME = 24,
         ESCARGOT_DEBUGGER_WAIT_BEFORE_EXIT = 25,
+        ESCARGOT_DEBUGGER_STOP = 26,
+        // These four must be in the same order.
+        ESCARGOT_MESSAGE_WATCH_8BIT_START = 27,
+        ESCARGOT_MESSAGE_WATCH_8BIT = 28,
+        ESCARGOT_MESSAGE_WATCH_16BIT_START = 29,
+        ESCARGOT_MESSAGE_WATCH_16BIT = 30
     };
 
     // Environment record types
@@ -374,6 +385,7 @@ class DebuggerRemote : public Debugger {
         : m_exitClient(false)
         , m_pendingWait(false)
         , m_waitForResume(false)
+        , m_watchEval(false)
         , m_clientSourceData(nullptr)
         , m_clientSourceName(nullptr)
     {
@@ -431,6 +443,7 @@ class DebuggerRemote : public Debugger {
     bool m_exitClient : 1;
     bool m_pendingWait : 1;
     bool m_waitForResume : 1;
+    bool m_watchEval : 1;
     String* m_clientSourceData;
     String* m_clientSourceName;
 

tools/debugger/debugger.py

@@ -69,6 +69,23 @@ def do_display(self, args):
         else:
             print("Non-negative integer number expected, 0 turns off this function")
 
+    def do_watch(self, args):
+        """ Add value to watched values display after breakpoints """
+        if not args:
+            write("Error: Argument expected\n")
+        else:
+            write(self.debugger.set_watch(args))
+    do_w = do_watch
+
+    def do_print_watches(self, _):
+        self.debugger.print_watches()
+    do_pw = do_print_watches
+
+    def do_watches(self, _):
+        self.debugger.list_watches()
+    do_list_watches = do_watches
+    do_lw = do_watches
+
     def do_break(self, args):
         """ Insert breakpoints on the given lines or functions """
         if not args:
@@ -85,6 +102,10 @@ def do_delete(self, args):
         """ Delete the given breakpoint, use 'delete all|active|pending' to clear all the given breakpoints """
         write(self.debugger.delete(args))
 
+    def do_delete_watch(self, args):
+        """ Delete the given watch """
+        write(self.debugger.delete_watch(args))
+
     def do_continue(self, _):
         """ Continue execution """
         self.debugger.do_continue()

tools/debugger/debugger_core.py

@@ -72,6 +72,10 @@
 ESCARGOT_DEBUGGER_WAIT_FOR_SOURCE = 43
 ESCARGOT_DEBUGGER_WAITING_AFTER_PENDING = 44
 ESCARGOT_DEBUGGER_WAIT_FOR_WAIT_EXIT = 45
+ESCARGOT_MESSAGE_WATCH_RESULT_8BIT = 46
+ESCARGOT_MESSAGE_WATCH_RESULT_8BIT_END = 47
+ESCARGOT_MESSAGE_WATCH_RESULT_16BIT = 48
+ESCARGOT_MESSAGE_WATCH_RESULT_16BIT_END = 49
 
 
 # Messages sent by the debugger client to Escargot.
@@ -101,6 +105,11 @@
 ESCARGOT_DEBUGGER_PENDING_CONFIG = 23
 ESCARGOT_DEBUGGER_PENDING_RESUME = 24
 ESCARGOT_DEBUGGER_WAIT_BEFORE_EXIT = 25
+ESCARGOT_DEBUGGER_STOP = 26
+ESCARGOT_MESSAGE_WATCH_8BIT_START = 27
+ESCARGOT_MESSAGE_WATCH_8BIT = 28
+ESCARGOT_MESSAGE_WATCH_16BIT_START = 29
+ESCARGOT_MESSAGE_WATCH_16BIT = 30
 
 
 # Environment record types
@@ -300,6 +309,8 @@ def __init__(self, channel):
         self.next_breakpoint_index = 0
         self.active_breakpoint_list = {}
         self.pending_breakpoint_list = {}
+        self.watched_values_list = []
+        self.waiting_for_watched_values_count = 0
         self.line_list = Multimap()
         self.display = 0
         self.green = ''
@@ -442,6 +453,15 @@ def process_messages(self):
                 self.prompt = True
                 return DebuggerAction(DebuggerAction.TEXT, self._receive_string(ESCARGOT_MESSAGE_EVAL_RESULT_8BIT, data))
 
+            elif buffer_type in [ESCARGOT_MESSAGE_WATCH_RESULT_8BIT,
+                                 ESCARGOT_MESSAGE_WATCH_RESULT_8BIT_END,
+                                 ESCARGOT_MESSAGE_WATCH_RESULT_16BIT,
+                                 ESCARGOT_MESSAGE_WATCH_RESULT_16BIT_END]:
+                self.prompt = True
+                self.waiting_for_watched_values_count -= 1
+                print("Watch: " + self._receive_string(ESCARGOT_MESSAGE_WATCH_RESULT_8BIT, data))
+                return DebuggerAction(DebuggerAction.WAIT, "")
+
             elif buffer_type in [ESCARGOT_MESSAGE_EVAL_FAILED_8BIT,
                                  ESCARGOT_MESSAGE_EVAL_FAILED_8BIT_END,
                                  ESCARGOT_MESSAGE_EVAL_FAILED_16BIT,
@@ -588,7 +608,7 @@ def send_client_source(self):
             self._exec_command(ESCARGOT_DEBUGGER_THERE_WAS_NO_SOURCE)
             return
         path = self.client_sources.pop(0)
-        if not path.endswith('.js'):
+        if not path.endswith('.js') and not path.endswith('.mjs'):
             sys.exit("Error: Javascript file expected!")
         with open(path, 'r') as src_file:
             content = path + '\0'+ src_file.read()
@@ -646,6 +666,16 @@ def set_break(self, args):
 
         return self._set_breakpoint(args, False)
 
+    def set_watch(self, args):
+        if not args:
+            return "Error: Value name expected"
+
+        if args not in self.watched_values_list:
+            self.watched_values_list.append(args)
+            return "Added watch: %s\n" % args
+        else:
+            return  "Already watching: %s\n" % args
+
     def delete(self, args):
         if not args:
             return "Error: Breakpoint index expected\n" \
@@ -734,8 +764,21 @@ def print_source(self, line_num, offset):
 
         return msg
 
-    def eval(self, code):
-        self._send_string(code, ESCARGOT_MESSAGE_EVAL_8BIT_START)
+    def print_watches(self):
+        if self.watched_values_list:
+            for var_name in self.watched_values_list:
+                self.eval(var_name, watch=True)
+                self.waiting_for_watched_values_count += 1
+            while self.waiting_for_watched_values_count > 0:
+                self.process_messages()
+
+    def list_watches(self):
+        print("Watched values:")
+        for var_name in self.watched_values_list:
+            print(var_name)
+
+    def eval(self, code, watch=False):
+        self._send_string(code, ESCARGOT_MESSAGE_EVAL_8BIT_START if not watch else ESCARGOT_MESSAGE_WATCH_8BIT_START)
         self.prompt = False
 
     def backtrace(self, args):
@@ -1165,3 +1208,7 @@ def breakpoint_pending_exists(self, breakpoint):
                     return True
 
         return False
+
+    def delete_watch(self, var_name):
+        self.watched_values_list.remove(var_name)
+        return "Removed watch: %s\n" % var_name

tools/debugger/tests/do_watch.cmd

@@ -0,0 +1,23 @@
+b do_watch.js:8
+watch num_a
+w num_b
+watches
+c
+watch num_c
+list_watches
+c
+print_watches
+c
+delete_watch num_b
+lw
+c
+c
+pw
+c
+c
+pw
+c
+c
+c
+pw
+c

tools/debugger/tests/do_watch.expected

@@ -0,0 +1,61 @@
+Connecting to: localhost:6501
+Connection created!!!
+Stopped at tools/debugger/tests/do_watch.js:1
+(escargot-debugger) b do_watch.js:8
+Breakpoint 1 at tools/debugger/tests/do_watch.js:8
+(escargot-debugger) watch num_a
+Added watch: num_a
+(escargot-debugger) w num_b
+Added watch: num_b
+(escargot-debugger) watches
+Watched values:
+num_a
+num_b
+(escargot-debugger) c
+Stopped at breakpoint:1 tools/debugger/tests/do_watch.js:8
+(escargot-debugger) watch num_c
+Added watch: num_c
+(escargot-debugger) list_watches
+Watched values:
+num_a
+num_b
+num_c
+(escargot-debugger) c
+Stopped at breakpoint:1 tools/debugger/tests/do_watch.js:8
+(escargot-debugger) print_watches
+Watch: 190
+Watch: 0
+Watch: 3333
+(escargot-debugger) c
+Stopped at breakpoint:1 tools/debugger/tests/do_watch.js:8
+(escargot-debugger) delete_watch num_b
+Removed watch: num_b
+(escargot-debugger) lw
+Watched values:
+num_a
+num_c
+(escargot-debugger) c
+Stopped at breakpoint:1 tools/debugger/tests/do_watch.js:8
+(escargot-debugger) c
+Stopped at breakpoint:1 tools/debugger/tests/do_watch.js:8
+(escargot-debugger) pw
+Watch: 325
+Watch: 3433993233
+(escargot-debugger) c
+Stopped at breakpoint:1 tools/debugger/tests/do_watch.js:8
+(escargot-debugger) c
+Stopped at breakpoint:1 tools/debugger/tests/do_watch.js:8
+(escargot-debugger) pw
+Watch: 415
+Watch: 35030164969833
+(escargot-debugger) c
+Stopped at breakpoint:1 tools/debugger/tests/do_watch.js:8
+(escargot-debugger) c
+Stopped at breakpoint:1 tools/debugger/tests/do_watch.js:8
+(escargot-debugger) c
+Stopped at breakpoint:1 tools/debugger/tests/do_watch.js:8
+(escargot-debugger) pw
+Watch: 550
+Watch: 36091613998583910000
+(escargot-debugger) c
+Connection closed.

tools/debugger/tests/do_watch.js

@@ -0,0 +1,9 @@
+let num_a = 100;
+let num_b = 2;
+var num_c = 33;
+
+for (let i = 0; i < 10; i++) {
+    num_a = num_a + 45;
+    num_b -= 1;
+    num_c *= 101
+}